report with hermes 2013

Construction of Satellite Ground Station

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Certificate

A project report on the topic of “Construction of Satellite Ground Station” was carried out by

undersigned students of BS (Hons., Session: 2009-2013) under the supervision of Sir Zia-ul-

Haq, Assistant Professor, and same are hereby submitted to the Department of Space Science,

University of the Punjab in partial fulfillment of the requirements for the award of the BS

(Hons.) degree in Space Science.

Dated:

Supervisor Chairman

Zia-ul-Haq Dr. Muhammad Ali

Assistant Professor Department of Space Science

Department of Space Science University of the Punjab, Lahore

University of the Punjab, Lahore

Serial No Names Roll no. Signature

01. Atiqa Ijaz Khan ss09-03

02. Syeda Rbiya Mehmood ss09-14

03. Usama Maqsood ss09-25

04. Faiza Shoukat ss09-26

05. Pervaiz Elahi ss09-27


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Dedication

This project report is dedicated to our respected teachers and parents who made us to see the

height of this achievement.


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Acknowledgement

All praises, to ALLAH Almighty, the most Merciful and Beneficial. And all the Blessings

from Almighty on us Who is the everlasting source of knowledge and wisdom.

Foremost we would like to pay our sincere gratitude to our Supervisor, Sir Zia-ul-Haq, for his

continuous support and assistance for our project study and report.

We are very grateful to our Chairman, Dr. Muhammad Ali, for providing us with such an

environment so to complete our project on time successfully.

We are also thankful to our respectable teachers for their immense knowledge throughout the

4-year degree program. So by here we are in a position of submitting our final year project

report.

We would like to Ronnie Nader, 1st Ecuadorian Astronaut / Mission Director at EXA, for his

support and help regarding online tracking using HERMES Project.


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Table of Contents

1) Abstract 09

2) Chapter 1: Introduction 11

3) Chapter 2: The Satellite System 14

a. Types of Satellites 14

i. Communication Satellites 15

ii. Earth Observation Satellites 16

iii. Navigation Satellites 17

iv. Military Satellites 17

v. Special Satellites 18

vi. Remote Sensing Satellites 18

vii. Weather Satellites 19

b. Component of Satellites 19

i. Payload 20

ii. Bus 20

c. Weather Satellite System 26

i. Categories of Weather Satellite System 26

ii. Working with Weather Satellites 28

iii. Weather Satellite Imagery System 29

4) Chapter 3: Working with NOAA 34

a. NOAA Satellite Series 34

b. Orbital Properties 37

c. Modes of Operation 38

d. NOAA Frequencies 38

e. Modulation Techniques 39

5) Chapter 4: Weather Satellite Receiver 41

a. Receiving System of Weather Satellites 41

b. Modes of Reception of Weather Satellites 43

c. Transmission Parameters for POES Satellite System 45

6) Chapter 5: Automatic Picture Transmission System 48

a. APT Transmission Format 49

b. Requirements for Building an APT System 50

7) Chapter 6: Construction of Antenna 56


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a. Omni-directional Antennas 56

b. Directional Antennas 57

c. Cross Antennas 58

d. Double Cross Antennas 58

e. Why we choose Double Cross Dipole Antenna? 60

f. Construction 61

i. Calculation of Dipole Rod Length 63

8) Chapter 7: Introduction to Wpeix 2000 B Receiver 65

a. Calibration 65

b. Selection Criteria for Receiver 66

9) Chapter 8: Introduction to WXtoImg 69

a. Software Features 69

b. Versions 69

c. Calibration 70

d. Why we choose WXtoImg? 74

e. Sample Images 75

10) Chapter 9: Online Tracking of Satellite Images 77

a. Background 77

b. Project Hermes 78

c. Modes of Operation 79

d. Implementation of Delta Mode 80

e. Future Expansion 82

11) Issues and Problems 84

12) Conclusion 85

13) Recommendation 86

14) Glossary 87

15) Performance 94

16) Software List 96

17) References 97


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List of Figures

1. Figure: Satellite 14

2. Figure 01: ANIK 16

3. Figure 02: Quick Bird 16

4. Figure 03: Navstar 17

5. Figure 04: Military Satellite 17

6. Figure 05: Galileo 18

7. Figure 06: Landsat 18

8. Figure 07: Meteosat 19

9. Figure 08: Component of Satellite 20

10. Figure 09: GOES 24

11. Figure 10: POES 27

12. Figure 11: GOES GVAR (United East Cost) 28

13. Figure 12: HRPT (Hurricane Emily) 42

14. Figure 13: APT (Europe) 42

15. Figure 14: WEFAX and HRI (Europe) 43

16. Figure 15: Commercial Pre-amplifier 45

17. Figure 16: APT Transmission Format 46

18. Figure 17: APT Ground Station 49

19. Figure 18: Antenna Requirement 50

20. Figure 19: WeSaCom APT-06 53

21. Figure 20: R2FX 53

22. Figure 21: Hamtronics 54

23. Figure 22: EMGO 54

24. Figure 23: Cross Dipole Antenna 58

25. Figure 24: Double Cross Dipole Antenna 59

26. Figure 25: Double Cross Dipole Antenna 59

27. Figure 26: Pipes of Antenna 61

28. Figure 27: Holders of Antenna 61

29. Figure 28: Pipes Assembly 62

30. Figure 29: Final Antenna 62

31. Figure 30: Dipole Phasing 63

32. Figure 31: Wpeix 2000 B 65


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33. Figure 32 Enter Your Location 71

34. Figure 33: Satellite Pass list 71

35. Figure 34: Volume Adjustment 72

36. Figure 35: Slant Correction 73

37. Figure 36: WXtoImg Interface 73

38. Figure 37: A Typical Decoded Image by WXtoImg 75

39. Figure 38: MSA Enhanced Image by WXtoImg 75

40. Figure 39: Sample Image by Project Hermes 77

41. Figure 40: Hermes Working 79

42. Figure 41: Implementation of Project Hermes 80

43. Figure 42: VRS Monitor 81

44. Figure 43: Listen Connection 81

45. Figure 44: Delta Client Side 82

46. Figure 45: Future Expansion 83

47. Figure 46: APT Setup 94

48. Figure 47: Audio Files of WXtoImg 94

49. Figure 48: NOAA 15 Image on WXtoImg 95


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List of Tables

1. Table 01: Satellite Categories 15

2. Table 02: Comparison of Satellites 31

3. Table 03: Comparison between Polar and Geostationary Satellites 32

4. Table 04: GOES 35

5. Table 05: NOAA 36, 37

6. Table 06: Orbital Properties of NOAA 37

7. Table 07: Modes of Operation 38

8. Table 08: NOAA Frequencies 38

9. Table 09: NOAA Modulation Techniques 39

10. Table 10: US POES Satellite Parameters 45

11. Table 11: Properties of APT 48, 49

12. Table 12: Comparison between Cross And Double Cross Antenna 60

13. Table 13: Comparison of Double Cross Antenna 60

14. Table 14: Comparison of Wpeix 2000 B 66

15. Table 15: Versions of WXtoImg 69, 70

16. Table 16: Comparison of WXtoImg 74


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Abstract

The world has progress to the century of technology where everything is in the click of a

second. Satellite images are one of the key aspects of advancement of this era. There come

many methods to deal with these images for educational, scientific, re-search, and military

purposes. The basic thing to do is to obtain them for a user. In order to provide this facility,

one of the applications is APT that is Automatic Picture Transmission. That is actually a low

resolution image by low orbiting satellites like NOAA.

The main objective of this project report is to establish an APT ground station to meet the

educational purposes of the student of our Department of Space Science, University of the

Punjab. It comes with antenna and decoder. This project report highlights the working and

building of an APT station at a reasonable cost. In future, the room of modification is still

available; it is just a starting towards the higher goals.


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Chapter 01


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Introduction

In the last few decades, the satellite reception system is more into consideration. The weather

satellite receiving system has evolved with time and come to this stage of advancement. Now

it is affordable for even small institute and department to have their satellite ground station.

That is in return one step forward at the educational level. NOAA is the most easily available

satellite for the weather reception.

The technique used here is of automatic picture transmission (APT). There are two modes of

this operation. Satellite imagery can be accessed by formally building an APT ground station,

using antennas, amplifier, decoders and software. Secondly it can also be tracked by online

systems.

This project report is started from the general information about the satellites and its types.

Weather satellite reception system is the key towards the better understanding of this system,

so this topic is also discussed here. It then mainly focused on the NOAA satellites and its

reception system, as per our need. NOAA polar orbiting satellite system is the foremost

requirement of the APT.

As the APT operate on polar satellites. Building of an APT ground station requires a little

basic work on the antennas. As antennas are building blocks of any reception system. For

signals to receive properly, another important part is pre-amplifier. The strength of the signal

is mostly depended upon the area where the signal is receiving. Other factors are also there.

As a result, the APT catches the signal as satellite passes through our mandatory track. Then

it is further decoded by the help of software, such as WXtoImg. Now the images are ready for

any kind of analysis.

For the satellite images to be captured and displayed, the setup requires a receiver. The

quality of the receiver defines the resolution of the images. This is an important portion of an

APT system. The apparatus used here is Wpeix 2000 B.

There many software available for tracking as well as decoding of the satellite images. It is

up to user demand, which software can display the finest images to meet up the demands of

users. They are all there in internet in free version and paid ones. Obviously, the paid one

carries the greatest features with it, which is a helpful key for experts.


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Another approach is here in the favor satellite reception system. Online tracking is available

now days. It gives the real time tracking of the satellite to the remote users. It gives relief to

thousands of users. As it is less than one click distance.

Another option for obtaining the satellite data is to get connected with Project Agora,

Hermes. By this way, the University should have a cooperation contract with EXA. Then

they generate the user name and password. We have to provide them with our public IP

address. After completing all this steps, it is now available for us to get the satellite images on

our pc.

These images can be further used in analysis from a layman to students, teachers, experts,

researchers, scientists, and all other fields. These images are also for military purposes.


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Contents

Types of Satellites

Communicational Sat

Earth Observing Sat

Navigation Sat

Military Sat

Special Sat

Remote Sensing Sat

Weather Sat

Component of Satellite

Merits

De-merits

Weather Satellite System

Categories

Working

Satellite Imagery

Chapter 02 Chapter 02


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The Satellite System

o deal with satellite system, the knowledge of the satellite is essential. Without this, it is

impossible to understand the processes of the satellite systems.

According to Frenzel,

“A satellite is a physical object that orbits a celestial body.”

Some satellites are natural, as the moon which is the natural satellite of earth. Some satellites

are made by scientists to go around the earth. These satellites provide us with valuable

information regarding weather, remote sensing etc. for communication satellites remain fixed

above the surface of earth and provide worldwide information.

Some satellites are for sending and receiving the signals. These signals are sent from a space

station on the surface of earth. These satellites receive the signal and re-broadcast it to other

places on the earth.

Some satellites sent and receive fax, telephone and

computer communication.

Other satellites observe the weather, feeding

weather information into giant computers programs

that help scientists know what the weather will be.

All weather reports on our TV news program are

getting their information from these satellites.

Figure: Satellite

Some satellites take pictures of earth‟s surface, sending back images that tell scientists about

changes that are going on around the world.

Types of Satellites

On the basis of usage, satellites are divided into following categories:

T


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1. Communication satellites

2. Earth Observation satellites

3. Navigation satellites

4. Military satellites

5. Special satellites

6. Remote sensing satellites

7. Weather satellites

Table 1: Satellite Categories

Communication Satellites:

Communication satellites are used for audio, video and data transmission. They carry large

dishes to capture radio waves and heavy solar panels for powering the sound amplifiers.

Their orbit is geosynchronous 22300 miles above earth‟s equator.

Examples:

Sputnik-1


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Nimbus-3

Westar-1

Arabsat-1A

Badar

TIROS-1

Figure 1: Courtesy: NASA Glenn Research Center (ANIK)

Earth Observation Satellites:

Earth observation satellites are used for photographing the earth to observe changes such as

earthquakes, and floods etc. They are at low

flying orbits at 90-300 miles.

Examples:

MOS-1/1b

JERS-1

ADEOS

ADEOS-II

ALOS

Figure 2: Courtesy: www.digitalglobe.com (Quick Bird)

http://www.digitalglobe.com/


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Navigation Satellites:

These satellites are used for global positioning system. It means that we can navigate by a

satellite. They orbit at around 90-300 miles.

Figure 3: (Navstar) Courtesy: www.tele.ntnu.no/radio/newresearch/navigation/avion.jpg

Examples:

GIOVEA & GIOVE B

GLONASS-M

PARUS

Navstar

Military Satellites:

These satellites are used to control the

military activity of the country. It usually

power up the systems. Their designs are

still not public. They are at both high and

low orbits, may be up to 22,300 miles. They

are approved in 1960‟s. And now become

an important part of defense system.

Examples:

COSMOS

SKYNET

MUOS Figure 4: Courtesy: US Department of Defense

REX

STRV 1A & 1B

RADCAL SAT

http://www.tele.ntnu.no/radio/newresearch/navigation/avion.jpg


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Special Satellites:

These satellites are used for space observation and re-search work. Space station is one of its

examples. It orbits at low altitudes. While on the other hand, deep space probes travel in an

elliptic orbit.

Examples:

Galileo

Mir Space Station

Mariner 9 Mars Orbiter

Magellan Venus Orbiter

Figure 5: (Galileo) Courtesy: NASA Glenn Research Center

Remote Sensing Satellites:

Remote sensing satellites provide a systematic way of observing physical phenomenon and

processes taking place on human‟s planet.

In remote sensing scientists described that

information transfer from the object or

phenomenon to a sensor by electromagnetic

spectrum. Sensor is placed on a satellite which is

specific for a particular portion of spectrum to

detect various objects. Therefore in remote

sensing satellite the sensor play main role.

Figure 6: Courtesy: www. landsat.gsfc.nasa.gov.htm

Examples:

Landsat (USA)

SPOT (France)

IRS (India)

Envi-sat (ESA)

http://landsat.gsfc.nasa.gov.htm/


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RADARSAT (Canada)

IKONOS

Quick bird

Orb View

Weather Satellites:

These satellites are used for photographing changes in cloud formation and climatic and

weather conditions. They have design in similar to earth observation satellites. A Low-flying

polar satellite circles every 2-hour at 300-600 miles above earth.

Examples:

Meteosat

COMS

GOES

NOAA

MTSAT-1R

TIROS 1-10

ORBVIEW-2(Sea star)

Figure 7: (Meto-sat) Courtesy: Richmond University, VA,

Teacher resources at oncampus.richmond.edu

Component of Satellites

A satellite consists of two main units:

Payload

Bus


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Figure 8: Communication Network

Payload:

It is the part of the satellite that provides communication.

Payload further consists of two main parts:

i. Repeater which receives the uplink signal amplifies it and converts it into

suitable downlink frequency.

ii. Antenna receives and transmits the signals to the ground stations.

Bus:

It provides all the necessary electrical and mechanical support to the payload.

Function of Bus:

Maintain the correct orbital position of the satellite at any specific location and to

keep the antennas pointing towards the required location. (AOCS)

Providing communication between the satellite and the ground stations by accepting

and conveying commands from and to the ground stations.

Commmunication Network

Space segment Payload & bus

Earth segment Earth receiving station station

Antenna


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Providing the DC power to all the operative components of the satellite (Power Sub

system)

Maintain the suitable temperature of various subsystems of the satellite

Bus consists of further components:

TTC (TELEMETRY, TRACKING & COMMAND)

a) Telemetry

It is used to report the status of the onboard systems of the satellite to the ground

stations.

The telemetry subsystem consists of 100 different electronic sensors that are used to

measure temperature, radiation level, power supply voltage, fuel pressure etc.

By that ground stations are able to know to the current status of the satellite.

At the earth stations a computer can be used to monitor, store and decode the

telemetry data so that the status of any system or sensor on the space craft can be

determined immediately by the earth station.

b) Tracking:

Tracking system is important during the orbital drifting phase of the satellite.

Beacon transmitters are usually provided on the space craft for tracking during the

launch and operation.

When a geostationary satellite tries to shift due to different disturbing forces the

tracking system becomes real important that tracks the satellite exact position.

Precise measurements of range is calculated by transmitting a pulse or a sequence of

pulses to the satellite and noting the time delay before the pulse is received again.

The propagation delay in the satellite transponder must be known accurately and more

than one earth station could be used to make range measurements.


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c) Command:

It receives the instructions from satellite ground stations, decodes the instructions and

send the commands back to the satellite for verification.

Basically the satellite contains a command receiver which receive signals transmitted

from earth stations.

The commands that are received by the satellite from earth stations are passed to the

computer from where they are processed for necessary action.

AOCS:

The purpose of AOCS is to provide the attitude determination and control to maintain

and sustain the required geostationary position.

The attitude of the satellite should be controlled so that the antennas could be pointed

be pointed towards the correct location on the earth.

Attitude control is also necessary in some satellites to keep the satellites solar panels

pointing towards the sun so as to get the maximum solar radiations at all times.

AOCS is maintained by satellite stabilization method and jet thrusters firing.

AOCS is first calculated when the satellite enters into its required GEO & becomes

stable.

PSS:

The function of the power subsystem is to provide DC power to all subsystems

throughout the life of a satellite.

For this requirement, the PSS must generate DC power, regulate it and provide an

alternative source when power cannot be generated by the space craft.

The early satellites used onboard batteries for power-up but these batteries were

exhausted quickly and could not be replaced.

Life of a satellite depends upon quality of the batteries and power drain.

Presently solar panels onboard the satellites are the basic power source.

On these solar panels lie a large no. of photocells connected in series and parallel

and can generate many kilowatts of energy.


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At times when the satellite goes into the eclipse means that the solar panels are

deprived of solar radiations and that time the solar batteries come into the action.

These batteries are not that large to give power for a longer time to the satellite.

It means that batteries are only used for a backup system in eclipses, in initial

satellite orientation and emergency conditions.

Its is mostly recommended that solar cells should be connected in parallel rather

than in series.

The operational status of the batteries (recharging, service etc) is controlled by the

ground stations.

Presently Ni-Cd batteries are used due to their high reliability and long life time.

Pyro Propulsion Subsystem

The function of the propulsion system is to generate thrust required for attitude and

orbit corrections.

The thrust required for attitude and orbit correction is large and mono propellants and

bi-propellants fuels are used for it. Force required by a thruster depends on the flow

rate of the fuel and specific impulse.

All the communication satellites require a propulsion subsystem to take the satellite

up, for its proper orientation, to put it into transfer orbit and finally into GEO.

Thermal Control Subsystem

It is very important that the mean space craft temperature and the temperature of all

the subsystems should be maintained in suitable limits (not too high that the space

craft may blast and not too low that the liquid fuel may freeze)

This subsystem mainly consists of passive devices that include thermal blankets that

lie on the exterior of the satellite which prevents the satellite from over heating.

It also contains controllable heaters that are either controlled by the satellite

automatically or by the earth stations automatically through TTC link.


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The performance and reliability of everything in the spacecraft is more or less temperature

sensitive.

Figure 9: Components of satellite

Merits of Satellites:

Following are the merits of satellites:

Satellite covers every portion of earth either customer is in rural area or urban area.

Satellite communication is not effected by the terrain of earth.

With the increase in distance between user and communication point there is no

increase in cost

Additional receive sites on a network can be added in few hours.

Satellite services are highly flexible.

Recently satellite technology has been used to connect internet with broadband

connections.

Satellite data is helpful for understanding and analyzing the global environmental

conditions

It is helpful to found earth natural resources.

Data collected from satellites is making able us to understand the processes and interactions

among land masses, oceans and atmosphere.


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De-merits of Satellites:

With the development in every field of life the technology is advanced and there are better

ways of doing everything. Decades ago people have no choice but to travel distance but now

communication via satellite is available. Satellite with thousands of advantages having some

disadvantages which are as follows:

Satellite dealing is bit expensive.

As satellite is at large distance from earth so a time lag between the messages sent

and received.

Satellite data transfer is susceptible to noise and interference

The bandwidth of satellite is becoming used up with time.

Congestion of frequencies

Note:

While discussing the satellite systems, not all the satellites facilitate us with the option of

APT (Automatic Picture Transmission). Now a day it is only available with us for the

weather satellites only as they (few of them) gives the facility for APT that can be used by

any of the end users specially students and researchers. Also APT is mainly used in the

meteorological and weather forecasting field only. So now we are going to focus our

attention to the weather satellites in particular.


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Weather Satellites System

eather satellites make it possible to observe world wide areas. Cloud images are the

one of the best satellite application and also other meteorological parameters can be

measured from satellites.

Categories of Weather Satellites

There are following two basics types of weather satellites:

Geostationary Orbiting Satellites

Polar Orbiting Satellites

Few important details about them are discussed below:

Geostationary Weather Satellite:

Geostationary satellites orbit the earth in the same time as it takes the earth to revolve once.

These satellites appear still from the earth. The geostationary orbit allows the satellite to

monitor the same region all the time.

Geostationary satellites transmit photographs to the receiving system on the ground as soon

as the camera captures the picture. The series of the captured photographs from these

satellites can be displayed in a sequence to generate a movie showing cloud movement. It

allows the forecasters to watch the large weather systems. Wind direction and speed by

monitoring cloud movement is also finding out. GOES satellites make day and night

observations of weather in a specific area and transmit real-time VISSR data. From Hawaii to

Maine, land features can be examined at 0.8 km. resolution. It is the primary function of

GOES satellite is to provide imagery of varying resolution.

W


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Merits:

It can view the whole earth at all

times.

It always locates at the same place

relative to the earth.

It can take and record images as

fast as once every minute.

Figure 10: GOES

Motion of clouds can be computed because its view is always from same perspective.

It also receives transmissions from free-floating balloons and automatic data

collection station around the world.

De-merits:

It provides less detail view of the earth as it located about 35,000 km in space.

Due to the earth curvature views are limited.

Polar Weather Satellites:

It is the other basic type of weather satellite. It is a type of satellite that orbits in a path that

closely follows the Earth's meridian lines, each revolution. As the Earth rotates to the east

under the satellite, each pass of the satellite monitors a small area running from north to

south, and, to the west of the previous pass. These strips can be pieced together to generate a

picture of a wide area. These satellites circle at lower altitude about 850 km. As polar

satellites can photograph clouds from closer than the high altitude geostationary satellites

therefore provide more detailed information about storm, wind or cloud system.

TIROS are a polar orbiting satellite (NOAA-class) that is launched by United States.it is the

principle source of environmental data. Temperature, humidity in the earth surface is

measured by these satellites. These also monitor cloud cover. To locate downed airplanes or

ships in distress it also carries Search and Rescue (SAR) transponders. Polar orbiting

http://satellites.spacesim.org/english/glossary/lr.html#merid


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satellites send back pictures to earth station via Automatic Picture Transmission (APT).

Figure 11: POES

Merits:

These are closer to the earth with an orbit of about 833 km above the surface.

The images obtained by polar orbits are more detailed.

They give fabulous view over Polar Regions.

De-merits:

These cannot see the whole earth‟s surface at any one time.

As the path of each orbit changes due to the earth‟s rotation so images of same

location are not obtained.

As most of the time the satellite is below the earth‟s horizon so it is limited to about

six or seven images a day.

Working of Weather Satellites

Weather satellites carry an instrument which is called radiometer (not cameras) that scans the

Earth to generate images. Radiometers usually have some sort of small antenna or telescope,

any scanning mechanism, and detectors that detect either visible, infrared, or microwave

radiation with the aim of monitoring weather systems all over the world.


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The data are then provided to various weather forecast centers of world and available over the

internet in the form of images. The time from satellite measurements to image availability

can be less than a minute because weather changes quickly.

The life span of instruments on the satellites is 3 to 7 years, although many of them last

longer than that.

Weather Satellite Imagery

Environmental satellites data is provided in several different formats. The most commonly

used formats on weather satellites used are the visible, infrared, and water vapor channels.

They are of three types:

Visible Imagery

Infrared Imagery

Water Vapor Imagery

Visible Satellite Imagery:

VIS imagery shows the amount of solar radiation reflected from the surface of earth. A VIS

image is an approximation of the percentage of incoming sunlight reflected by a surface

called albedo. In satellite VIS imagery, highly reflective areas are represented by lighter tones

and low reflective areas are represented by dark tones. On the surface of earth the features

vary in their reflectivity therefore can be easily distinguished by VIS image.

In Visible Imagery

Thick clouds appears white

Thinner clouds appear in light medium gray tones.

The oceans appear nearly black.

The land on the nature of the surface features appears as various shades of gray.


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Infrared Satellite Imagery:

The IR sensors measure the amount of infrared energy emitted by the surface of earth and

atmosphere. In this type of imagery the amount of energy emitted depends on the temperature

of the surface. This information can be used to measure thermal proportion of the earth.

in conventional IR imagery the colder areas appear as light gray tones i.e. white and warm

areas appear dark tones of gray i.e. black.

The scale of an infrared image is composed of 256 gray shades ranging from white

representing coolest temperature to black representing warmest temperature.

In Infrared imagery:

The highest or coldest cloud tops appear white.

Low clouds may appear in light shades of gray.

Water surface appears darker shades of gray.

Water Vapor Satellite Imagery:

As the earth and atmosphere emit energy then the clouds and suspended water vapors absorb

specific wavelength. The remaining energy is transmitted through the atmosphere. Most IR

sensors take advantage of the infrared band because it allows accurate measurements of

temperature of earth and tops of clouds. Some satellite sensors study the radiation absorbed

and by studying the IR energy at these wavelengths the atmospheric gas concentration can be

studied without the interference of surface features of earth.

The widely used applications of this concept are channel 9 (7.3 microns) and channel 10 (6.7

microns) on GOES VISSR sensor. Energy present in this channel is absorbed by water

vapors. The images that are taken in these channels are used to point out large concentration

of water vapors.

In Water Vapor imagery:

The darker regions are the areas where very less amount of water vapor exists.

The lighter regions are very moist.


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Water vapors are very important tool for weather analysis and prediction because it not only

shows the cloud pattern but also shows the moisture content in the atmosphere. This allows

the meteorologists to observe large scale circulation patterns even in the absence of clouds.

Note:

After discussing the weather satellites in general, we are now going for the NOAA satellites.

They are under special consideration as this series (NOAA satellite series) is the most

authentic data provider globally and is majorly available to layman for free. And most of all it

is equipped with APT Setup.

A general comparison is given here that shows why we chose NOAA.

Sr.No Satellite Operational

Status

APT* HRPT* LRT*

01. Trios -- Yes No No

02. Nimbus -- Yes No No

03. NOAA Yes Yes Yes No

04. Meteosat Yes No Yes Yes

05. MetOp Yes No Yes Yes

06. Insat Yes No Yes Yes

07. Metsat Yes No Yes Yes

08. GOES Yes No Yes No

09. Electro Yes No Yes Yes

10. Feng Yun Yes No No Yes

Table 02: Comparison of Satellites

* APT (Automatic Picture Transmission), HRPT (High Resolution Picture Transmission), LRT (Low Resolution

Transmission)

Our main focus is on polar satellites not on the geo-stationary satellites. The few of the

reason behind them are as follows:

Options Geo-stationary Satellites Polar Satellites

Weather Satellite Yes Yes


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APT No Yes

HRPT Yes No

Complexity of antenna More than Polar, expensive Less than Geo-stationary,

cheap

Availability of receivers Expensive Cheap

Decoder Complex Programming Easy Programing

Table 03: Comparison between polar and geo-stationary

Now it is clear from the above mention facts, that the NOAA satellite best serve our purpose.

That is in-return a polar satellite. In the next section, we will explore the NOAA satellites.


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Contents

NOAA Satellite System

Orbital Properties

Modes of Operation

NOAA Frequencies

Modulation Techniques

Chapter 03


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Working with NOAA Satellites

he NOAA_ “The National Oceanic and Atmospheric Administration” along with the

collaboration of the NASA_ “The National Aeronautics and Space Administration” has

a major role in the development of the satellite programs. NOAA has a renowned history in

the establishment of the weather satellites from “Polar Orbiting Environmental Satellites”

(POES) to “Geostationary Orbiting Environmental Satellites” (GOES).

Started from the momentous moment on April 1, 1960, when the world first weather satellite

was launched named TRIOS (Television Infrared Observation Satellites) from Cape

Canaveral, FL under the supervision of NOAA. Followed by the series of NOAA-1 launched

in the year 1970.Then by the joint effort of NOAA and NASA, they launched the series of

TRIOS-N (the TRIOS Next generation) by mid-1970. At present time, the NOAA-19 is the

fifth and last of its kind launched by 2006.

This then turned to the successful, ever growing technological advancement in this field till

now the year 2013.

The NOAA Satellites Series

Under the NOAA, it launched two major series of satellite age:

Geostationary Orbiting Environmental Satellites (GOES)

Polar Orbiting Environmental Satellites (POES)

They have one major difference that is; POES series capture the earth on the orbital locations

where normally geostationary satellites are unable to capture the images. The geostationary

satellites have the potential to get the full east or west disk of the earth as per requirement.

Below are given the summary of the satellites launched by the NOAA for polar as well as

geostationary satellites.

T


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Geostationary Orbiting Environmental Satellites (GOES):

Following are the GOES series of NOAA satellites:

Series

No.

NOAA

Satellites

Launched

Date

Current

Position

Series

01. SMS-1 May 17, 1974 De-active SMS-A

02. SMS-2 Feb 06, 1975 De-active SMS-B

03. GOES-1 Oct 16, 1975 De-active GOES-A

04. GOES-2 Jun 16, 1977 De-active GOES-B

05. GOES-3 Jun 16, 1978 De-active GOES-C

06. GOES-4 Sep 09, 1980 De-active GOES-D

07. GOES-5 May 22, 1981 De-active GOES-E

08. GOES-6 April 28, 1983 De-active GOES-F

09. GOES-7 -- De-active --

10. GOES-G May 03, 1986 De-active --

11. GOES-7 Feb 26, 1987 De-active GOES-H

12. GOES-8 April 13, 1994 De-active GOES-I

13. GOES-9 May 23, 1995 De-active GOES-J

14. GOES-10 April 25, 1997 De-active GOES-K

15. GOES-11 May 03, 2000 De-active GOES-L

16. GOES-12 July 23, 2001 Active GOES-M

17. GOES-13 May 24, 2006 Active GOES-N

18. GOES-14 Jun 27, 2009 Active GOES-O

19. GOES-15 Mar 08,2011 Active GOES-P

Table 04: GOES list

Where,

SMS = Synchronous Meteorological Satellite Program

GOES = Geostationary Orbiting Environmental Satellites


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Polar Orbiting Environmental Satellites (POES):

Following are the list of the NOAA polar satellite series, sorted by the launching dates:

Serial

No.

NOAA

Satellites

Launched

Dates

Current

Position

Series

01. TRIOS-1 April 01, 1960 De-active --

02. TRIOS-2 Nov 23, 1960 De-active --

03. TRIOS-3 July 12, 1961 De-active --

04. TRIOS-4 Feb 08, 1962 De-active --

05. TRIOS-5 Jun 19, 1962 De-active --

06. TRIOS-6 Sep 18, 1962 De-active --

07. TRIOS-7 Jun 19, 1963 De-active --

08. TRIOS-8 Dec 23, 1963 De-active --

09. TRIOS-9 Jan 22, 1965 De-active --

10. TRIOS-10 July 02, 1965 De-active --

11. ITOS-1 Jan 23, 1970 De-active TRIOS

12. NOAA-1 Dec 11, 1970 De-active ITOS-A

13. ITOS-B Oct 21, 1971 De-active --

14. NOAA-2 Oct 15, 1972 De-active ITOS-D

15. ITOS-E July 16, 1973 De-active --

16. NOAA-3 Nov 06, 1973 De-active ITOS-F

17. NOAA-4 Nov 15, 1974 De-active ITOS-G

18. NOAA-5 July 29, 1976 De-active ITOS-H

19. TIROS-N Oct 13, 1978 De-active --

20. NOAA-6 Jun 27, 1979 De-active NOAA-A

21. NOAA-B May 29, 1980 De-active --

22. NOAA-7 Jun 23, 1981 De-active NOAA-C

23. NOAA-8 Mar 28, 1983 De-active NOAA-E

24. NOAA-9 Dec 12, 1984 De-active NOAA-F

25. NOAA-10 Sep 17, 1986 De-active NOAA-G

26. NOAA-11 Sep 24, 1988 De-active NOAA-H

27. NOAA-12 May 14, 1991 De-active NOAA-D

28. NOAA-13 Aug 09, 1993 De-active NOAA-I


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29. NOAA-14 Dec 30, 1994 De-active NOAA-J

30. NOAA-15 May 13, 1998 Active NOAA-K

31. NOAA-16 Sep 21, 2000 Active NOAA-L

32. NOAA-17 Jun 24, 2002 De-active NOAA-M

33. NOAA-18 May 20, 2005 Active NOAA-N

34. NOAA-19 Feb 06, 2009 Active --

Table 05: NOAA list

Where,

TRIOS = Television and Infrared Observational Satellites

ITOS = Improved TRIOS Operational Satellites

TRIOS-N = TRIOS Next Generation

Orbital Properties

The orbital characteristics of the currently activated NOAA satellites are given below:

Serial

No.

NOAA

Satellites

Inclination

(Degrees)

Altitude

(km)

Time

Period

Operational

Status

Type

01. NOAA-15 98.5 807 101.1

min

AM

Secondary

Sun-

Synchronous

02. NOAA-16 99.0 849 102.1

min

PM

Secondary

Sun-

Synchronous

03. NOAA-18 98.74 845 102.12

min

PM

Secondary

Sun-

Synchronous

04. NOAA-19 98.7 870 102.14

min

PM Primary Sun-

Synchronous

Table 06: Orbital Properties of Currently Active Satellites


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Modes of Operation

NOAA data reception can be easily conducted by the aid of fully equipped ground station

within the radio frequency range. This is called Direct Readout. It deals with the two types of

services of AVHRR:

1. HRPT (High Resolution Picture Transmission)

2. APT (Automatic Picture Transmission)

Serial No. NOAA

Satellites

HRPT Data Transfer

Rate

(Kbit/sec)

APT Data Transfer

Rate

(Kbit/sec)

01. NOAA-15 Yes 665 Yes 9.6

02. NOAA-16* Yes 665 No 9.6

03. NOAA-18 Yes 665 Yes 9.6

04. NOAA-19 Yes 665 Yes 9.6

*As NOAA-16 does not carry APT, so it is omitted in the further discussion in this document. Table 07: Modes of operation

NOAA Frequencies

For currently activated NOAA satellites, the operational frequencies of these are as follows:

Serial No. NOAA Satellites Frequencies (MHz)

01. NOAA-15 137. 35 & 137.62

02. NOAA-18 137.35 & 137.9125

03. NOAA-19 137.77 & 137.10

Table 08: NOAA Currently Active Satellites Frequencies


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NOAA Modulation Techniques

The NOAA currently activated satellites works on different kind of modulation process as

follows:

Serial No. NOAA Satellites Modulation

01. NOAA-15 PCM/PM

AM/FM

02. NOAA-18 PCM/PM

AM/FM

03. NOAA-19 PCM/PM

AM/FM

Table 09: NOAA Modulation Techniques

Where,

PCM = Pulse Code Modulation

PM = Phase Modulation

AM = Amplitude Modulation

FM = Frequency Modulation

The APT acquires data whenever the satellite is in the range. For NOAA, it passes 4 times

daily. The number of satellites passes depends upon the latitude of the station. High station

can get transmission more than 4 times a day. But each station receives data only for 15

minutes, while the satellite is in the range.


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Contents

Receiving System

Modes of Reception

Transmission Parameters

of POES



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Weather Satellite Receiver

Introduction

n order to receive the satellite images, the basic requirement is of the receiver. Here few

questions rises what is a receiver? What types of receiver are weather satellite receivers?

How it works? The type and quality of the receiving system of satellite images defines the

how good are images.

According to Frenzel,

“A receiver is a component, as a function and portion that obtain arriving radio signals or

transfer them in a usable form.”

What is a Receiver?

Receiver essentially executes different operations. It extracts the desired signal from the

signals that is getting by antenna that may contain un-desired signals. Receiver eliminates all

un-desired signals. Receiver also sufficiently increases the wanted signals to a useable

quality. Ultimately the receiver retrieves the wanted signal and gives it to the utilizer.

Receiving System of Weather Satellite

Obtaining signal from weather satellite is not simple as it looks. Different factors are

responsible in obtaining a clear and good image in throughout the transmission. The primary

difficulty is that signal transmitted by satellite is polarize and is not very strong. In different

situation directional antennas can be used to get good results.

Different very high frequency (VHF) receiver can obtain the band of satellite at 137 MHz

range frequency modulation. However they mostly have missing adequate sensitivity to get a

good or noise eliminated signal. Scanners also have problem, they receive signal at very

narrow bandwidth, as it is optimum for the noise signal. On the other hand, the weather

satellite NOAA needs a broader bandwidth receiver, however not broader as that utilize for

broadcast FM signals. The impact of obtaining signals at limited bandwidth is that big signals

show the luminous portion of signal, are cut off.

Currently, few of the weather satellite receiving system are available:

I


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1. GOES GVAR Satellite Receiving System: (morcom.com)

This is a highly advanced PC-based work station or capturing real time high resolution

images from geostationary

satellites.

Figure 12: United East Cost (morcom.com)

2. NOAA HRPT Satellite Receiving System: (morcom.com)

This is a real time receiving and

displaying polar orbiting

satellites imagery. These images

are under the AVHHR highly

resolution.

Figure 13: Hurricane Emily (morcom.com)

3. MSG Eumetcast Satellite Receiving System: (morcom.com)

They work on the images received by Eumetcast via Eumetcast broadcasting route.

Commercially work under C and Ku band worldwide.


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4. APT Satellite Receiving System:

This is an uncomplicated system work with low resolution images with low orbiting

satellites. These satellites are powerful enough that one can obtain images at 10 degree above

the horizon. It is a type FAX transmission mode by the aid of satellite. APT carries tow

sensors: visible and infrared. Images from this system are receivable by 137 MHz frequency

range antenna.

Figure 14: Picture of Europe transmitted in APT mode by a NOAA

satellite. It is post processed in false colors.

Modes of the Weather Satellite Reception System

There are so many weather satellites in world that are continuously transmitting their images.

These are in different resolution, modes, and frequencies.

Mainly they are of four types:

1. APT:

Again APT comes for its long range availability. It is a fully assembled automated weather

satellite reception system, with a special start and stop tone accepted by decoder. Its mode is

in FM with 120 lines per minute.


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2. WEFAX and HRI:

It stands for Weather Facsimile work on AM mode with 240 lines per minute. It works best

for polar as well as geostationary satellites. Unlike APT, it uses standard tone. Having a voice

audio channel with AM carries of

2.4k Hz modulated with 1.6k Hz

video signal.

It works with METEOSAT,

GOES, INSAT, and GOMS.

WEFAX images are easiest to

record with analog mode while

HRI (High Resolution Image)

images are high resolution.

Figure 15: (Europe and Maghreb pictured by METEOSAT 7)

3. MSG:

It transmits images in resolutions: low and high. Mostly in C band that ranges 3.7-4.2 GHz.

4. HRPT or CHRPT:

They capture high resolution images by polar orbiting satellites. The resolution of the images

is up to 1.1km/pixel. They are operating under the frequency of 1.69 GHz with analyzing 5-

10 multi spectral channels. But they carry 120MB space of the hard disk. So it is reserve for

the experts.


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Transmission Parameter for POES Reception System

Receiving systems for POES are the main aspect for the quality control and resolution of the

APT images. Mostly they are similar to FM high band, solid state receivers. These types of

receivers are mostly used by police and fire departments. This is type of receiver can be

modified to receive the NOAA downlinks. So every APT should meet the minimum

requirements for the complete APT video reception.

According to the United States, the following are the minimum parameters set for the APT

reception system of POES satellites operating there:

Serial No. Parameters U.S. POES

01. Frequency 137.9125, 137.62, 137.1 MHz

02. Carrier Modulation Analog FM/AM

03. Carrier Deviation +/- 17 KHz

04. Polarization Right hand Circular

05. Transmitting Power 5 watts

Table 10: US POES APT Parameters

Few important points should be kept in mind while choosing the receiving system are:

1. Frequency of the Transmitted APT:

The APT band is 137-138 MHz. This is a very narrow band. So it is necessary to obtain a

receiver that is capable of operating under these ranges.

2. Type of RF Signal Modulation:

The signal can be modulated on FM or AM techniques.

3. Sensitivity of the Receiver:

It means that the receiver should be able enough to detect the very low and weak signals. The

noise should be filtered and should not affect the signal quality.

4. Selectivity of the Receiver:


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It is the important area of transmitting signal. The receiver can be a radio receiver or a

scanner.

5. Bandwidth of the Transmitted Signal:

The bandwidth of the transmitting signal is effected by:

a. Satellite transmission deviation:

For ideal APT system, it could afford the deviation of +/- 20 KHz.

b. Doppler shift:

It causes the frequency shift as the satellite approaches and passes by. The ideal values for

APT are 40 KHz.

6. Selection of Pre-Amplifier:

Pre-amplifier means that it has to be mounted after the antenna but before the decoder. The

use of pre-amplifier is to strengthen to weak signal. As the POES transmit signal at a very

low strength, so a good quality amplifier is a must job.

One should take care of the amplifier, because it has to expose itself to the environmental

conditions. So it should be weather resistance and

water repellent in order to achieve the long time

use.

They are needed for long feed lengths. The

relatively shorter feed length does not involve

any kind of amplifier. It is developed to attain the

good quality and noise free signal.

Figure 16: Commercial Pre-amplifier


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Contents

Introduction

Transmission Format

Requirements of Building

an APT Ground Station

Antenna

Receiver

Tacking Software

Decoder



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Automatic Picture Transmission System

utomatic picture transmission (APT) uses modified vidicon tube TV cameras. It

continuously transmits analog signal on VHF band (136-138 MHz). The resolution has

been reduced to 4 km in order to capture the larger area but in a low resolution.

Few of the important general characteristics of APT are as follows:

Serial

No.

01. Camera Diameter 2.54 cm

02. FOV (Field of View) 108 degrees

03. Focal Length 5.7 mm

04. Objective Lens f/1.8

05. Picture Capturing Time 8 sec

06. Picture Transmission

Time

200 sec

07. Transmitting Power 5 watt (37dBm)

08. Carrier Modulation 2.4 kHz AM subcarrier on FM carrier (DSB), normally

within the rage of 1500-2500 Hz

09. Polarization Right Circular (RCP)

10. Grey Scales 256 Levels (8-bit)

11. Operational

Frequencies

136-138 MHz

12. Operational Imagery

Channels

Visible & IR

13. Day Time Imagery

Mode

Visible & IR

14. Night Time Imagery

Mode

Infrared (IR)

15. Signal Analogue

A


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16. Data Transfer Rate 120 lines per minute (lpm) or 2 lines/sec

17. Resolution 4km/pixel

Table 11: General Properties of APT

Considering the normal altitude of 700 km for APT system, the foot print of the satellite is all

about 1200 km * 1200 km having the nadir with 7.6 km of resolution.

APT Transmission Frame Format

The APT data we received is continuously transmitted on analog signal, with two AVHHR

(Advance Very High Resolution Radiometer) channels. Any of the channels can be chosen by

the APT ground station.

1. A visible channel is used to provide day time imagery. Figure 17: (N. Benabadji, 2004)

2. One infrared (IR) channel

is use to deal with day and

night time imagery.

3. Second IR channel is used

as a replacement of the

visible channel in the

night time.

Each image frame has two main

parts:

I. On the left side of the

image, synchronization

pattern is shown in

vertical black lines in

each image.

II. On the bottom, telemetry

data is shown with other

information in grey scales wedges.


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Requirements for Building an APT Ground Station

To get the images form the weather satellites using APT mode, the general hardware required

for these are as follows:

a) An antenna

b) Receiver

c) Tracking

Software

d) Decoder

Figure 18: (N. Benabadji, 2004)

Antennas:

“An antenna or aerial as it is sometimes called is one or more electrical conductors of a

specific length that radiate waves generated by a transmitter or that collect radio waves at the

receiver.”

(Frenzel, Communication Electronics, 3rd edition)

Types of Antennas:

Antennas are different of hundreds of types. Few of them are:

a) Yaggi Antenna: One of the high gain antennas. They are normally designed for HF

to UHF.

b) Dipole Antenna: It is same that of the electrical conductors of varying length. It is

under the type of omnidirectional antenna.

c) Helical Antenna: By using conductors or multiple conductors to wind a helix,

formed a helical antenna. These types of antenna are good for the transmission of the

circularly polarized radiation.

d) Quadrifiler Helical Antenna: It gives a complete hemispherical reception of the

radiation. This type of antenna is under the use of the APT system. Because of it is of

circular polarization. And its gain pattern matches that of the satellite. That helps to

receive the almost constant signal from horizon to horizon.


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Limitations of Antennas other than Weather Satellite Receiving Antennas:

Antennas that are not specifically sketch for the weather satellites, carries two major

problems.

a) Bandwidth: The bandwidth required for automatic picture transformation (APT) is

within the range 30-50 KHz. On the other hand, scanners have too broader bandwidth

as 180 KHz and some have too limited as 15 KHz.

b) Quality: The other problem is that for weather satellite receiving antennas, one

requires best performing receiver that can give:

Good sensitivity,

Best signal to noise ratio, and

Protected with other adjoining transmission.

Properties of Antenna:

The antenna used for the APT should have following properties:

a. Antenna Gain:

“It is a form of amplification.”

On the basis of elevation (in degrees), the antenna gain varies;

From 5 to 90 to 5, the gain should be of 11 dB

From 15 to 90 to 15, the gain should be of 09 db.

b. Bandwidth:

“It is that portion of the electromagnetic spectrum occupied by a signal.”

For best results, the APT requires bandwidth of 30-50 kHz, under the FM band.


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c. Beam width:

“It refers to the angle of the radiation pattern over which a transmitter‟s energy is directed or

received.”

For APT, it should follow the few of the conditions such as:

It should be wide enough to provide with easy tracking.

It should be narrow enough to provide with reasonable gain.

d. Polarization:

“In the transmission and reception of the radio waves is the orientation of the magnetic an

electrical field with respect to the earth. The direction of the electric field specifies the

polarization of the antenna.”

Now a day, generally APT uses polarization of „Right Circular Polarization‟ (RCP).

e. Frequency:

“It is simply the number of times a particular phenomenon occurs in a given period of time.”

The frequency requirement for the APT system generally ranges from 136-138 MHz.

f. Orientation:

One of the main alignments of the antenna is its orientation, which should be in proper facing

to the satellites. As the satellites is not always in the true polar direction. It should be set with

0 degrees to True North.

g. Antenna Pre-amplifier:

The need of the antenna pre-amplifier is due to the fact that the received signal is too low to

detect with normal setup. The distortion in the signal is enhanced, when the distance between


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antenna and receiver increased. To overcome this problem, a pre-amplifier is used. Its main

theme is to amplify the signal up to a detectable level.

Receiver:

“A receiver is a component, as a function and portion that obtain arriving radio signals or

transfer them in a usable form.”

For the operation of the APT to work properly, the receiver of a good quality is required. It is

the most important part of the APT ground station. It should carry few of the properties:

Noise-free

Equipped with AFC (Automatic Frequency Control)

And AGC (Automatic Gain Control)

Signal strength meter for tracking purpose

Few of the weather satellites receivers are

given below:

a) WeSaCom APT-06

This is computerized system arranged with the

high-Q helical filters.

Figure 19: WeSaCom (APT-06)

b) R2FX/R2ZX/R2FU

This is along with strong R2ZX/R2FU

filtering process and controlled by computer.

Figure 20: R2FX


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c) Hamtronics R303-137

It is a dedicated system without the computer control.

Figure 21: Hamtronics

d) EMGO RX 134141MHz

This package comes with LCD screen and control of

computer.

Figure 22: EMGO

Track Prediction Software:

As we have to deal with the satellites that have different orbital paths and time periods. In

order to use them for proper tracking, different software packages are required.

Few of them are written as follows:

WXTRACK

ITRACK

J-TRACK

FOOTPRINT

Decoders:

The images transmitted from the polar orbiting satellites come in a format, which needed to

be decoded.

APT deals with the many of the software such as:

APT Decode

Sat Signal


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Contents

Introduction

Omni-directional Antennas

Directional Antennas

Cross Antennas

Double Cross Antennas

Construction of Antenna

Calculation of Dipole

Rod Length



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Construction of Antenna

he main part for the building of an APT ground station is the construction of an

antenna. The antenna is the basic part of any transmission as well as for reception

system. So due its importance, one should have a strong control over the maintenance of the

antenna so it would work properly. Its construction is under the user, so it could be done with

proper savings. Commercially available antennas are bit expensive for beginners.

As it is known fact that APT is working under VHF mode. So the antenna used for this

should be compatible with range of frequencies of APT. Construction of antenna deals with

the frequencies, attenuation, polarization, bandwidth, directivity and signal strength. So this

includes both types of antenna:

Omni-directional Antenna

Directional Antenna

Omni-directional Antennas

They are said to be the non-oriented antennas, as they transmit and receive signal in all

directions. In many communication systems, it is desirable. In other words, they are at 360

degrees. Means uniform with the radiations. They are generally cheap in price. And they are

good for:

a) Small distances

b) Large coverage areas

They are designed for the high gain. But generally gain is less than 9 dB

Its main disadvantage is the low efficiency of the power transmission. As it can deal with the

signal from all directions so much of the power is wasted. Just a small portion is retrieved to

the ground station.

There are many antennas that are still operating on all directions. Few examples of omni-

directional antennas are:

T


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a) Cross Antenna

b) Double Cross Antenna

c) Quadrifiler Antenna

d) Turnstile Reflector

Directional Antennas

As by its name, it turns towards the directivity of the radiations. The signal can be transmit

and received at certain directions. And help to get the desired signal without dissipating it. It

is generally for:

a) Small coverage area

b) High target density

Its main advantage is that it saves power. It can focus the transmitting power to a narrow

beam that can be directed to the ground station.

Directional antennas can be:

a) Bi-directional: That can transmit and receives signal in two directions.

b) Uni-directional: That can transmit and receives signal only in one direction.

Few of its examples are:

a) Yaggi Antenna

b) Crossed Yaggi Antenna

Points to remember:

To have the best signal strength, the antenna should point towards the satellite as it passes. It

should be kept in mind that there is not any kind of metal object obstruction between antenna

and satellite. So it should be mounted on the highest available place. At least it is 1 meter

above the ground level. Any other kind of obstacle also degrades the signal quality and

strength.


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Cross Antennas

This is the antenna that work for APT ground system. Its working is under the VHF and UHF

band.

It is made up of four copper wires cut from a thick copper wire. One pair is used to receive

and other to transmit. It should be strong enough to stay stiff without any support. Aluminum

serves the best for the purpose.

The copper wires should link

in a way that each pair crosses

to other perpendicularly.

One disadvantage is that the

antenna pattern for this

comprises the four lobes.

Figure 23: (Cross Dipole Antenna) courtesy: www.thornett.net.htm

Double Cross Antennas

To overcome the disadvantage of the cross dipole antenna, it is modified to get the double

cross dipole. It has the same structure but now with 8 elements. One more pair of 4-crossed

dipole is used. This symmetry is known as “Commutated eight-element cross dipole array”.

It is optional to be mounted at 45 degrees relative to the first pair.

This configuration is now able to cover the dead angles in the antenna footprint.

At the same time, it has a major drawback. That is, the elongated objects can never come in

alignment with transmitting or the receiving dipoles.

http://www.thornett.net.htm/


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However, the addition of this passive element

produces a strong cross-coupling. And it is fairly

constant. So it is possible to subtract it from the

background using subtraction algorithm that is

not discussed in this report.

Figure 24: (Double Cross) Courtesy: www.digitalham.htm

Figure 25: (Double Cross) Courtesy: www.simpleantenna.htm

http://www.digitalham.htm/

http://www.simpleantenna.htm/


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Why we choose Double Cross Dipole Antenna???

The main question here arises after discussing all those types of antenna. That why we select

Double Cross Dipole Antenna? The following comparison shows the reason behind it:

Cross Antenna Double Cross Antenna

Omni-directional Yes Yes

Availability Yes Yes

Handling Easy Easy

APT Reception Yes Yes

Construction Easy Easy

Surface Cross Sectional

Area

Less than Double More

Power wastage More than Double Low or less

Table 12: Comparison between Cross and Double Cross Antenna

Now the double cross dipole antenna is selected good for our purpose. Let‟s make it more

clear by following comparison:

Double Cross QHF Yaggi

Directivity No No Yes

Coverage Area Large Large Small

High Target

Density

No No Yes

Cost Normal (280 PKR) Expensive (1400

PKR)

Moderate (500 PKR)

Power Efficiency Less Less More

Construction Easy Hard Easy

Availability Sometimes No Yes

Size Manageable Constant Constant

Dead Angle Less than yaggi Causes fluctuation in

signal

More

Table 13: Comparison of Double Cross


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Construction

The construction of antenna is the basic part of any reception system. It should be prepared

with proper care. There are many themes available for it. The procedure which we follow to

develop the antenna is just a simple and general one.

The short notes are as follows:

First we acquired 8 steel pipes of 39 cm and 01 cm diameter.

Then we need 2 V-shaped holders.

Each holder carries 4 pipes within it.

A one long tube is required to hold all this assembly as per need.

Then at the end join the pairs holding with 4 pipes each at 45 angle with each other.

Figure 26: Pipes of Antenna

Figure 27: Pipe Holders


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Figure 28: Pipe Assembly

Figure 29: Final Antenna


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Calculation of Length of the Dipole Rod:

To calculate the length of the rod, that will be used for the construction of the antenna. This

method is given below: (www.crossdipoleantenna.htm)

For VHF Band,

Speed of light = 300 *106 m/sec²

VHF frequency = 137 MHz

Full wavelength (λ) = 300/137 = 2.189 m

Dipole Length = λ/2 = 1.0945 m

Dipole Phasing = λ/4 = 0.547 m

Into centimeters,

Dipole Phasing = 0.547 * 100 = 54.7 cm

For Velocity Correction,

54.7 * 0.66 = 36.13 cm = 36 cm approx.

Mostly for VHF band, the length of the rod

ranges from 36-39 cm.

Figure 30: Cross Dipole Phasing

http://www.crossdipoleantenna.htm/


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Contents

Introduction

Calibration of Wpeix



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Introduction to Wpeix 2000 B

s per the requirement of the APT system, it should have a receiver for properly

receiving the signals. These signals are feed into the antenna and then decoded by

software.

In market, there are many receivers available now a day. There are companies that are

working on it. Receivers of different types are there according to their specifications.

The receiver which we used for our project is Wpeix 2000 B by Vanguard.

Figure 31: Wpeix 2000 B

Calibration

Following are few of the main points regarding the usage of Wpeix 2000 B in order to

receive the satellite signal in time:

1. Antenna does not need to be connected at this point.

2. Plug in the power adapter.

3. Check the panel fuse by a voltmeter.

4. Turn ON the receiver, and check the red LED‟s.

5. Put the SCANNIG in AUTO position and SQULECH on full.

6. If LED‟s are scanning but not in sequence, a wire is short in circuit. (Return to

Vanguard for repair)

A


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7. If LED is ON but not scanning, the clock circuit may be out.

8. Change SCANNIG into MANUAL and push the RED button and release it. On doing

each time it should advance to the next. If not then the wire from that switch is broken

or clock is not working properly.

9. Turn the SQLECH on the midway, the volume should suddenly stops.

10. Remove the bottom cover and check the LED mounted on the main board. It should

not turn ON. It should only blink only at scanning.

Selection Criteria for Receiver

The main question here, why we choose Wepix 2000 B? It has following reasons:

Wepix 2000

B

Emgo WeSaCom Hamtronics R2FX

Availability Yes No No No No

Expense Moderate Yes Yes Yes Yes

Programing Erasable N/A N/A N/A N/A

Guidance Available N/A N/A N/A N/A

LCD Screen No Yes No No No

Computer

Control

Yes Yes Yes No Yes

Desired

Signal

Filtering

Yes No Yes No Yes

Frequency

Controller

Yes Yes Yes Yes Yes

Gain

Controller

Yes Yes Yes Yes Yes

Software

Connectivity

Easy Easy Easy Complex Easy

Table 14: Comparison of Wpeix 2000 B


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Due these reasons, we have selected the Wpeix 2000 B for the continuity of our project

report.


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Contents

Introduction

Software Features

Versions

Latest Version

Calibration

Sample Images



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Introduction to WXtoImg Software

he WXtoImg software is developed by Craig Anderson, from Auckland, New Zealand

of Abstract Technologies. It is available in both free version and professional version.

Software Features

It is fully assembled system for decoding satellite images in real time mode, having an

interactive graphical interface.

Few of the main features are given below:

1. It is used for recording, decoding, and viewing images.

2. It can support map layouts, 3D-images, animation, project transformation, automatic

web page creation, color enhancements, and control for many other satellites receivers

and scanners.

3. It supports APT from polar orbiting satellites as well as WEFAX from geostationary

satellites.

4. It has built in system for image processing techniques.

5. It can produce images in any of the format: JPEG, AVI, BMP, PBM and PNG.

6. It can produce images form scanners also that have very low bandwidth.

7. It also uses the techniques to correct the Doppler shift.

Versions of WXtoImg

All the versions are as follows starting from the oldest one to the newest one:

Old to New 2.6.6p2 2.6.6p3 2.6.7

2.6.8 2.6.9 2.6.9-5 2.7.2

2.7.3 2.8.9 2.8.11 2.8.12

2.8.14-c 2.9.3 2.9.4 2.9.5-c

2.9.9 2.9.10 2.10.6 2.10.7

T


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2.10.8 2.10.9 2.10.10 2.10.11

Table 15: Versions of WXtoImg

Version “2.10.11”:

The version which we used in our project is version 2.10.11. It is the latest available version

of the WXtoImg now a day.

The latest version contains many new experimental features. Few of its main features are as

follows:

1. It has the ability to exclude particular satellites from the web page.

2. Have experimental micro adjustment of map position.

3. Have the experimental fix over the PRO scan control.

4. It can fix bugs.

Calibration

Few of the things should be re arranged in order to start using this software. One can adjust

according to ones need. Generally they are as follows:

1. At the start, connects receiver audio output in line input of soundcard by a cable.

2. Set your location, by entering latitude and longitude. Enter the desired sea level

height.

If the city has the population over 100, 00 then check it under the look up table. If one don‟t

know about the desired city then look for the nearest city. Otherwise enter the latitude and

longitude of the city manually.

North and East should enter as positive numbers.

While South and West as negative numbers.


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Figure 32: Entering the location

3. Update the Keplers.

At present, to access the Keplerian data use Celestrak without any account. However, it can

be accessed through

www.space-track.org. Once you get

the account, change the password.

The in the Option Menu, open

Internet Option and enter the new

user name and password. Now

update the Keplers for downloading

the latest orbital elements for the

weather satellites.

Figure 33: Satellite Pass List

http://www.space-track.org/


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4. Check the satellite passes at desired location.

It gives the details about the satellite passing through the required area. The time is given in

both UTM and local zones. It can look ahead from 7 days to 1 month, up to the requirement

of the user.

5. Adjust the audio setting.

Check the Mixer Control in the File Menu. The select Record and check the Auto. It will take

few moments, until the satellite is under the range. Avoid using scroll during recording, as it

will cause the image to split.

The image will be decoded after the satellite has

passed through. After the decodation the overall

volume of the image is shown on the right hand

side of the status line below the image. The

volume should lies in the range 40 – 85.

If it is up to 92, then volume should be

decreased.

If it is up to 24.7, it should be increased

If the volume is too high, it will cause

clipping.

If it is too low the data will be lost.

Figure 34: Volume adjustment

6. Make a slant correction.

After the image is decoded and displayed, the image is slightly slanted at the top. The image

is slanted from top to bottom due Doppler shift. Hold on the top of the image and scroll it to

the bottom while holding the edge.


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Figure 35: Slant Correction

Make it sure that pointer over the same edge while moving down from top to bottom. Then

at the end of the image, release the

button.

The WXtoImg automatically adjust the

sampling frequency. It can estimate it

for all the satellites. Select Set. And

ensure that the sampling frequency is

saved at the end.

At the end, there is a graphical interface

of this software.

Figure 36: WXtoImg Interface


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Why we choose WXtoImg???

The following are the reasons, for why we choose this particular software:

WXtoImg APT Decoder Sat Signal

Understanding Good Normal Less

Availability Yes Yes Yes

User Friendly

Interface

Yes Yes Yes

Free ware Edition Easily available Not easily Not easily

Installation Easy Easy Take time

Control Easy Not easy Not easy Table 16: Comparison of WXtoImg

Due to better understanding of this software, and other reasons, we have selected WXtoIMg

software for our project report.


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Sample Images

WXtoImg is used to have many of the satellite images all around the world. Few of images

are given below as sample:

Figure 37: A typical image on decoding by WXtoImg

Figure 38: A typical image on decoding by MSA


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Contents

Introduction

Background of EXA

Project Hermes

Objectives of Hermes

Modes of Operation of Hermes

Implementation of Delta Mode

Procedure of Delta Mode

Future Expansion

Chapter 09


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Online Tracking of Satellite Images

n present days, it is now a common fact to deal with the satellite images in daily routine.

The most advance countries are updating their projects and facilities by using satellite

data. So it is important to access them on ease. Thus, the availability of the satellite data

should be in the hands of users.

Today this credit goes to the EXA (Ecuadorian Civil Space Agency), who provides the world

with online tracking of satellite images.

Background of EXA

EXA is a civilian NGO charged of administration and execution of Ecuadorian Civil Space

Program. It is the only Ecuadorian agency that has been accepted in the “International

Astronautical Federation” with vote and voice into the general assembly.

Few of the projects, under EXA are:

Project Daedalus

Project Poseidon

Project Hermes

Project Agora

EXA trained its first astronaut, on 2007, named Cmdr. Ronnie Nader.

I


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Figure 39: Image of ash cloud at Tungurahua volcano processed by Sony VAIO laptop with 3G cellular Modem, as per the Hermes System

Project Hermes

Hermes is capable of many abilities like command, tracking, detecting, and

receiving/transmitting data and voice from satellites and space station within their range.

Actually it is a “Space Flight Control Center” (SPCC). Or it is a robotic type of SPCC.

Besides this, it can be controlled and operated on the internet. It sends the space craft signal

to the registered authorities over the network, then that is used by them on their ground

station. It is basically built for the academic purposes. And its data is utilizes by many

universities and institutions.

Objective of Hermes:

Hermes has to deal with its few objectives in order to expand the scope of it utilization. Few

of them are given below:

1. It is the 1st ever ground station of its kind that is available on internet network and is

in the hand of public.

2. It is there to meet up the education demand of the community by giving them the

access to the in-orbit space crafts by lowering their costs.


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3. It is helpful for the experts without having their ground stations.

4. It is also participating, with the other nations and institutions to control the manned

space crafts.

Figure 40: Hermes Working

Modes of Operation

Hermes-A/Minotaur was 1st became operative on 6

th June, 2009. It is an initiative of EXA

and has coverage of maximum up to 22,000 km.

It has 4 modes of operation, digitally and analogically. There are as follows:

1. Mode-A(Alpha):

Reception of data from orbit and relay trough Internet.

2. Mode-B(Beta) :


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Uplink/downlink full duplex connection between computers on the Internet and orbiting

space crafts.

3. Mode-C(Gamma):

It deals with half duplex voice conversation between any computer on the Internet and

manned spacecraft.

4. Mode-D(Delta):

Automated APT/HRPT signal relay from weather satellites to any computer on the Internet.

Figure 41: Hermes Implementation

Implementation of Project Hermes Delta Mode

With all the define modes of operation of project Hermes, the Delta mode is of main

importance. It is the implementation of this project, that the world has an internet access to

in-orbit satellites. The Hermes gateway tacks satellite pass automatically having APT/HRPT

when comes in its range.

Procedure:

1. The computer has to be previously registered to the Hermes.


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2. It will generate the username and password at your given public IP address for

security purposes.

3. To access the gateway, small software is required named VRS Monitor. With:

Server name: hermes-a.exa.ec

Speed: 256

Figure 42: VRS Monitor

4. Software is required for decoding that is

WXtoImg.

5. Then press the Connect to access the Hermes.

Then a window appears.

6. On this window, check the 3rd

box. This is for

Delta Mode.

Figure 43: Listen Connection

7. The telemetry data is required for satellite to be tracked. That is downloaded by

decoding software. Or it is directly accessed from the web site: www.celestrak.com

on free.

8. Find the satellite pass through at the location.

9. Once the satellite is in the range, the program will just open the Hermes Delta Serve

and start processing audio frequency (AF) as the satellite sends the data.

10. After the satellite has passed, the software will start decoding images using the

different enhancement techniques as per preference.

http://www.celestrak.com/


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Figure 44: Delta Mode Client Side

Future Expansion of Hermes

Due to high demand and use, the project Hermes is on its way of expansion. To provide with

global coverage, the future expansion plans are as follows:

1. Hermes-A is the 1st of the 5-planned SFCC.

2. Hermes-B will be installed in Galapagos Island.

3. Hermes-C and Hermes-D will be installed in Tacna, Peru, and Puerto Montt, Chile.

4. Hermes-E will be installed in Ecuadorian Antarctic Research at Pedro Vicente

Maldonado.

5. The expansion to Europe, UAE, Pakistan, and India is proposed.

6. When the system is fully ready, it will be able to transmit an hour on un-interrupted

connection between users and earth orbit.


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Figure 45: Hermes Future Expansion


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Issues and Problems

While dealing with this project, we came across, few of the issues, regarding its construction.

Few of them are mentioned below:

1. We have constructed the double cross antenna, because its accessories are easily

available. While on the other hand, the availability of the piping for other types of

antennas that are there for the weather satellite receiving system are expensive.

2. There was issue in our receiver. One of the IC Mm2716 Q was flashed out. So that,

we were unable to re-program it.

3. As the receiver model is very old, so the frequencies available on it are omitted now.

4. Moreover, the receiver needs to be returned to the Vangurad for repairs.

5. Therefor we were unable to test it.

6. We were getting the tone as the satellite passes through, but we were not getting the

required images.


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Conclusion

After all dealing this with Automatic Picture Transmission System, it is obvious now that

satellite images are now in hands at no issue. The room of betterment is always there. The

images obtain from this method is a step forward on in this field. New technologies are on

their way. The satellites are now equipped with modern system that helps such system to get

the images as per need. Many companies are in market for developing weather satellite

receiving system. Soft-wares are there to decode these images.

These images can be further utilized in many ways depending upon the requirement. Many

image processing techniques can be applied for further analysis.


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Recommendation

Now, here it comes, how to go further in this area for extra progress. The upcoming satellite

will be equipped with LRT system (Low Resolution Transmission), a modified version of

APT. The quality of the antenna and pre-amplifier, the type of satellite receivers, the newer

version of software, and image enhancement techniques are updating on daily basis. That can

in return add more options to the APT system.

It can be further extended from polar satellites to the geo-stationary satellites. But this, on the

other hand, need more complex apparatus and staff.


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Glossary

ADEOS Advance Earth Observing Satellite by Japan

ALOS Advance Land Observation Satellite by Japan

AM Amplitude Modulation, controls the amplitude of the carrier signal

Analog Signal Is a continuous signal

Antenna An antenna or aerial as it is sometimes called is one or more electrical

conductors of a specific length that radiate waves generated by a

transmitter or that collect radio waves at the receiver

Antenna Gain It is a form of amplification

APT Automatic Picture Transmission

APT Decoder Software used for decoding

Arab Sat It own and operates 5 satellites

AVHRR Advanced Very High Resolution Radiometer

AVI Audio Video Interleave, is a multimedia format by Microsoft

Badar Pakistan‟s 1st Earth Observation Satellite by Suparco

Bandwidth It is the portion of electromagnetic spectrum occupied by signal

Beam width It is angle of radiation patterns over which signal is received or

transmits

Bi-directional That can transmits and receive data in two directions

Antenna

BMP Bitmap Image File, is a raster graphic file format

C-Band Used for satellite communication at 4-8 GHz

CHRPT Capture High Resolution Picture Transmission

COMS Communication, Ocean Meteorological Satellite by Korea


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COSMOS Constellation of small Satellites for the Mediterranean basin

Observation by Korea

Cross Antenna A type of omni-directional antenna used for APT transmission

dBm Decibels relative to milli-watt

Decoder It is device that un-do the encoding

Digital Signal It is a digital discrete time signal

Dipole Antenna It is same that of the electrical conductors of varying length. It is under

the type of omnidirectional antenna.

Directional A type of antenna that has a certain direction of receiving and

transmitting

Antenna signals

Downlink Messages from satellite to ground station

Double Cross A modified cross antenna for APT reception

Antenna

DSB Double Side Band

Doppler Shift It causes the frequency shift as the satellite approaches and passes by

Envi-sat In-operative Earth Observing Satellite by

EMGO Satellite Receiver

Eumetcast Eumetcast is a multi-service dissemination system based on standard

Digital Video Broadcast (DVB) technology. It uses l

telecommunication geostationary satellites that are available

commercially

FM Frequency Modulation, encodes information as variation in

instantaneous frequency of carrier signal


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FOOT PRINT Satellite Tracking Software

Frequency It is a number of times a specific phenomenon occurs in given period

of time

FOV Field of view

Galileo Global Navigation Satellite by European Union (EU) and European

Space Agency (ESA)

GIOVE Galileo In Orbit Validation Element by ESA

GLONASS Globalnaya navigatsionnaya sputnikovaya sistema, Or, Global

Navigation Satellite System by Russia

GOES Geostationary Orbiting Environmental Satellite by US

GOES GVAR GOES Variable Format for infrared image data

GOMS Geostationary Operational Meteorological Satellite by Russia

HF High Frequency 3-30 MHz for radio communication

Hamtronics Satellite Receiver

Helical Antenna Made up of conducting wire in from of helix

HRPT High resolution Picture Transmission

HRI High Resolution Image

Hz Hertz, unit of frequency. Number of cycle per second of a phenomenon

IKONOS 1st publically available Earth Observation High Resolution Satellite

System by USA

INSAT Indian Satellite

ITOS Improved TRIOS Operational Satellite

IR Infrared


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IRS Indian Remote Sensing Satellite

I-track Satellite tracking Software

JERS Japanese Earth Observation Satellite

JPEG Joint Photographic Experts Group for lossy compression

J-track Satellite tracking Software

Landsat Remote Sensing Satellite (Original Name: Earth Resources

Technology Satellite) by USA

LPM Lines per minute (lpm)

MOS Marine Observation Satellite by Japan

MSA Multi Spectral Analysis

MSG Meteosat Second Generation by Europe

MTSAT Multifunctional Transport Satellites are a series of weather and

aviation control satellites by Japan

MUOS Mobile User Objective System by US

NASA National Aeronautics and Space Administration

Navstar Navigation System using Time and Ranging (GPS system) by USA

Nimbus The Nimbus satellites were second-generation meteorological research

and development (R&D) spacecraft by USA

NOAA National Oceanic and Atmospheric Administration

Objective Lens is the one at bottom near the sample

Omni-directional It transmits and receive signal in one direction

Antenna

Orb-view Formally called Micro-lab developed by Orbital Imaging Cooperation

by USA


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PARUS-type Russian Constellation of Communication and Navigation Satellites

PBM Portable Bit Map, a graphic file format

PCM Pulse Code Modulation Technique to digitally represent analog

sampled signal

PM Phase Modulation that encodes information as variation in

instantaneous phase of carrier signal

PNG Portable Network Graphics, file format was created as the free, open-

source successor to GIF

POES Polar Orbiting Environmental Satellite by USA

Polarization In the transmission and reception of the radio waves is the orientation

of the magnetic an electrical field with respect to the earth. The

direction of the electric field specifies the polarization of the antenna

Power The rate at which energy is transferred

Pre-amplifier Used to amplify the receiving signal

QHF Quadrifiler helix Antenna used for APT system

Quick-bird High Resolution Earth Observation Satellite by Digital Globe

R2FX Satellite Receiver

RADAR SAT Canadian Constellation of Remote Sensing Satellites

RADCAL Radar Calibration by USA

RCP Right Circular Polarization

Receiver A receiver is a component, as a function and portion that obtain

arriving radio signals or transfer them in a usable form

Resolution The smallest possible feature that can be detected

REX Radiation Experiment by USA

RF Radio frequency (3 kHz – 300 GHz)


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SAR Search and Rescue Transponders

Sat Signal Apt Software Decoder

Sea Star Operated by NASA

Sputnik Artificial Earth Satellite by Soviet Union

SKY NET Military Satellite by UK Ministry of Defense

SMS Synchronous Meteorological Satellite by USA

SPOT Système Pour l‟Observation de la Terre by France

Squelch It is a circuit function that acts to suppress the audio and video output

of the receiver of the system in the absence of desired strong input

signal

STRV Space Technology Research Vehicle by UK

TRIOS Television Infrared Observation Satellite by USA

TRIOS-N Television Infrared Observation Satellite-Next Generation by USA

Turnstile Antenna A type of double cross antenna

UHF Ultra High frequency 300-3000 MHz for cellular and military services

UTM Universal Transverse Mercator

Uni-directional It can receive and transmit signal in one direction only

Antenna

VHF Very High Frequency (30MHZ – 300MHz)

VIS Visible

VISSR Visible Infrared Spin Scan Radiometer

Watt One joule per second

WEFAX Weather facsimile


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WeSaCom Satellite Receiver

Westar by Western Union

Wpeix2000 B Satellite Receiver

WXtoImg Satellite Receiver Software

WX-track Satellite Tracking Software

Yaggi Antenna One of the high gain antennas. They are normally designed for HF to

UHF.


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Performance

The following are images of our performance:

Figure 46: APT Setup

Figure 47: Audio Files on 24th Au, 2013 at 06:04 UTC


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Figure 48: Image of NOAA 15


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Software List

WXtoImg

www.wxtoimg.com

APT decoder

www.aptdec.htm

VRS Monitor

www.remotelisten.htm

http://www.wxtoimg.com/

http://www.aptdec.htm/

http://www.remotelisten.htm/


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References

Books

1. Joseph A. Angelo, Jr, Frontiers in Space: Satellites, http://www.factsonfile.com

2. Definitions from: Louis E. Frenzel, Communication Electronics: Principles and

Applications (3rd

Edition). McGraw-Hill INTERNATIONAL EDITIONS

PDF Files

The following are arranged date-wise and alphabetically:

03-10-12

1. http://docs.lib.noaa.gov/rescue/TIROS/TL798M4T341964.pdf

2. http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19630013799_1963013799.pdf


04-10-12

1. http://satelliteconferences.noaa.gov/Miami04/docs/weds/NOAA-FUTURE-DRO.pdf

13-03-13

1. http://docs.lib.noaa.gov/rescue/TIROS/QC87954A681963.pdf


29-05-13

1. http://www.cder.dz/download/Art7-1_1.pdf

14-07-13

1. http://www.nws.noaa.gov/com/files/nwshighlevelorgchart_01-12-2012.pdf

2. http://www.osd.noaa.gov/download/JRS012504-GD.pdf

22-07-13

1. http://www.iau-neyshabur.ac.ir/nokhodchian/satellite.pdf

http://www.nws.noaa.gov/com/files/nwshighlevelorgchart_01-12-2012.pdf

http://www.osd.noaa.gov/download/JRS012504-GD.pdf


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2. http://www.ieee.li/pdf/viewgraphs/fundamentals_satellite_communication_part_1.pdf

3. http://www.ituarabic.org/2007/Disaster-Relief/FinalDocs/3rd Day/SessionXII/Doc58-

Globalstar.pdf

4. http://userspages.uob.edu.bh/mangoud/ms-sat1.pdf

5. http://www.usingenglish.com/files/pdf/advantages-and-disadvantages-of-future-

technologies.pdf

26-07-13

1. The HERMES Internet to Orbit gateway, UNOOSA, Graz, Austria – 2009

http://www.unoosa.org/pdf/sap/2009/graz/Programme_3September.pdf

Research Articles

1. Benabadji. N., Hassani. A., and Belbachir. A. (2004). Hardware and Software

Considerations to Use NOAA Images. Rev. Energ. Ren, Vol.7, p 1-11.

2. Charles. H.V. A User Guide to Construction of Inexpensive Automatic picture-

Transmission Ground Station. Goddard Space Flight Center Greenbelt, Maryland.

(1967).

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19670029628_1967029628.pd

f.

3. Charles. H.V. (1968) Constructing Inexpensive Automatic picture-Transmission

Ground Station. NASA SP-5079, p 1-57.

4. Gary. D. History of NOAA Satellite Program. 2011.

http://www.osd.noaa.gov.

5. Major C.I.T., Kenney. J., and Richards. R. (1964). Consideration Program for

Automatic Picture Transmission from TRIOS VIII. Consideration Aeronautics

and Space Journal, Vol. 10, p 103-106.

6. Patrik. T., and Jerry. M. (2008). Signal Plotter: A Tool for Evaluation APT

Antenna Performance. Group for Earth Observation, Vol. 20, p 6-12.

7. Using a Virtual Ground Station as a Tool for Supporting Higher Education, Jafer,

Klesh, Nader, Koudelka – IAC 2010.3

8. 61st International Astronautical Congress, Prague, IAC-10-E1.1.2 - A Satellite In The

Classroom: 2nd Grade Students Work With Real-Time Satellite Images - Solberg -

Academia Cotopaxi, Quito, Ecuador

http://www.unoosa.org/pdf/sap/2009/graz/Programme_3September.pdf

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19670029628_1967029628.pdf

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19670029628_1967029628.pdf

http://www.osd.noaa.gov/


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9. 61st International Astronautical Congress 2010 - Space Communications And

Navigation Symposium (B2) - Project Agora: Simultaneously Downloading A Satellite

Signal Around The World, ”, Jaffer, Klesh, Nader, Koudelka

Websites

The following are arranged date-wise and alphabetically:

29-05-13

1. http://www.emgo.cz/www_fa/meteosat_englisch_how.html

2. http://jcoppens.com/sat/howto/receive.en.php

3. http://nssdc.gsfc.nasa.gov/nmc/experimentDisplay.do?id=1963-054A-02

30-05-13

1. http://www.astrosurf.com/luxorion/qsl-satellites-reception2.htm

2. http://noaasis.noaa.gov/NOAASIS/ml/meteor.html

3. http://www.qsl.net/g4hbt/wxsats.htm

4. http://www.wraase.de/e_apt06.htm

5. http://www.zarya.info/Frequencies/Frequencies136.php

13-07-2013

1. http://celebrating200years.noaa.gov/resources.html#satellites

2. http://www.n2yo.com/satellites/?c=3

3. http://www.n2yo.com/satellites/?c=4

4. http://weather.gc.ca/satellite/

14-07-2013

1. http://www2.ncdc.noaa.gov/docs/podug/html/c1/sec12.htm

2. http://www.pco.noaa.gov/org/NOAA_Organization.htm

3. http://poes.gsfc.nasa.gov/noaa-heritage.html

4. http://www.g4ilo.com/wxsats.html

5. http://www.ncdc.noaa.gov/oa/pod-guide/ncdc/docs/klm/html/c4/sec4-2.htm

http://www.zarya.info/Frequencies/Frequencies136.php


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6. http://www.noaa.gov/about-noaa.html

7. http://noaasis.noaa.gov/NOAASIS/ml/genlsatl.html

8. http://www.oz9aec.net/index.php/gnu-radio/gnu-radio-blog/451-howto-receive-and-

decode-noaa-apt-images-with-the-fun cube-dongle-and-gqrx

9. http://www.oso.noaa.gov/poesstatus/spacecraftStatusSummary.asp?spacecraft=15




13. http://planet.iitp.ru/english/spacecraft/noaa.htm

14. http://www.srh.weather.gov/srh/jetstream/remote/satellite.htm

15-07-13

1. http://goes.gsfc.nasa.gov/text/goesnew.html

2. http://elecaskar.blogspot.com/2012/08/part-1-home-weather-satellite-receiver.html

3. http://myweb.tiscali.co.uk/wxsatellite/wxtoimg.htm

4. http://www.time-step.com/products_apt.htm

5. http://www.weatherscience.net/My_APT_Station.html

6. http://www.wxtoimg.com/hardware/

17-07-13

1. http://www.antenna-theory.com/antennas/main.php

21-07-13

1. https://sites.google.com/site/projagora/instructions/delta-mode---weather-images

22-07-13

2. http://electriciantraining.tpub.com/14189/css/14189_135.htm

3. http://www.fi.edu/weather/satellite/history.html

4. http://www.gma.org/surfing/sats.html

5. http://history.nasa.gov/weathsat.html

6. http://sat232.blogspot.com/2011/12/disadvantages-of-satellites.html

7. http://satellitecommunicationzone.com/disadvantages-of-satellite-communication

8. http://www.satellites.spacesim.org/english/engineer/copy/

9. http://www.stella2000.com/the-advantages-of-satellite-images/


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10. http://www.satimagingcorp.om/characterization-of-satellite-remote-sensing-

systems.html

11. http://www.telesat.com/about-us/why-satellite/advantages-satellites

12. http://www.telescope.org/nuffield/pas/moon/moon9e.html

13. http://www.ustudy.in/node/3529

14. http://www.weatherdefender.com/Features.aspx

15. http://www.vectorsite.net/ttgps_2.html

Un-identified Dates

1. http://antenna-theory.com/antennas/main.php

2. http://crossdipoleantenna.htm

3. http://turnstileantennaforsatellite reception/digitalham.htm

4. http://GOES-NEWS.htm

5. http://www.astrosurf.com/luxorion/qsl-satellites-reception2.htm

6. http://www.hffax.de/html/simple_apt_antenna.html

7. http://www.morcom.com/satellite_imaging.html

report with hermes 2013

Education

weather satellite receiver

poes satellite system

construction of antenna

system of weather satellites

apt ground station

noaa satellite series

satellite pass list

apt system