01 mn1790 introduction

8/13/2019 01 MN1790 Introduction

http://slidepdf.com/reader/full/01-mn1790-introduction 1/82

MN 1790 1 - 1

©

T E C H C OM

C on s ul t i n g ®

Introduction: ContentsIntroduction: Contents

GSM and SBS fundamental aspects concerning Radio Network Planning

• Planning Objectives & Principle Planning Steps

• Specifics influencing Radio Network Planning

• Site Survey & Site Investigation

• Antenna Types

• Antenna Parameters

• Antenna Patterns

• Antenna Tilt (Mechanical and/or Electrical)

• (Effective) Antenna Height

• Antenna Diversity

• Antenna Cables

• Antenna cables and Intermodulation

• Antenna Near Products

• Exercises



MN 1790 1 - 2

©

T E C H C OM


GSM and SBS fundamental aspects concerning RadioNetwork Planning

GSM and SBS fundamental aspects concerning RadioNetwork Planning

Implementation of additional hardware to improve QOS

Extension of coverage area

Implementation of new technologies (e.g. HSCSD, GPRS, EDGE)

Network extension

Fine tuning of the existing network without addition of new hardware

Reduction of interference on Air interface

Network optimization

Connecting the links between the different network elementsNetwork integration

Download and activation of network element specific software and databasesCommissioning of the network elements

BTS, BSC, TRAU, MSCInstallation of the network elements

Number and location of BTSs, BSCs, and MSCs

Number and type of links between the network elements

Type of BTSs and antennas (sectorised, omni-directional)

Number of TRXs per cell

Frequencies of serving and neighbor cells

BSICs

LACs

(GSM) Network planning (design)

RemarksSteps



MN 1790 1 - 3

©

T E C H C OM


Cellular network

• partial overlap of cells

• only a few frequencies per cell

• frequency re-use distance

1

1

2

2

4

4

5

5

6

67

7

3

3

GSM and SBS fundamental aspects concerning RadioNetwork Planning: Cellular Concept

GSM and SBS fundamental aspects concerning RadioNetwork Planning: Cellular Concept



MN 1790 1 - 4

©

T E C H C OM


GSM and SBS fundamental aspects concerning RadioNetwork Planning: TDMA Concept

GSM and SBS fundamental aspects concerning RadioNetwork Planning: TDMA Concept

TDMA frame: 4.615 ms

Time

Time Slot0.577 ms

TDMA frame No. 0180 TDMA frame No. 0181

1 2 3 4 5 6 7 1 2 3 4 5 6 70 0



MN 1790 1 - 5

©

T E C H C OM


GSM and SBS fundamental aspects concerning Radionetwork Planning: FDMA Concept

GSM and SBS fundamental aspects concerning Radionetwork Planning: FDMA Concept

UPLINK

25 MHz

75 MHz

890 MHz

1710 MHz

915 MHz

1785 MHz

DOWNLINK

935 MHz

1805 MHz

960 MHz

1880 MHz

25 MHz

75 MHz

GSM900

GSM1800

1 2

200 kHz

124

374

guard band

1 2124

374



MN 1790 1 - 6

©

T E C H C OM


GSM and SBS fundamental aspects concerning RadioNetwork Planning: Cell Types

GSM and SBS fundamental aspects concerning RadioNetwork Planning: Cell Types

360°

omni directional cell

180°

180° sector cell

120°

120° sector cell



MN 1790 1 - 7

©

T E C H C OM


GSM and SBS fundamental aspects concerningRadio Network Planning: Cell Types


8 km

35 km

100 km

GSM 900 Extended Cell

Standard Cell: GSM 900

Standard Cell: GSM 1800



MN 1790 1 - 8

©

T E C H C OM




Concentric cell

Inner area: TRX with low power for capacity

Complete area: TRX with high

power for coverage

Hierarchical cells

Different layers of cells fordifferent coverage areas



MN 1790 1 - 9

©

T E C H C OM


GSM and SBS fundamental aspects concerning RadioNetwork Planning: Logical Channels

GSM and SBS fundamental aspects concerning RadioNetwork Planning: Logical Channels

logical channels

control channels traffic channels

BCH CCCH DCCH

FCCH

BCCHSCH

AGCHPCH FACCH

SACCHSDCCH

TCH/F

RACHTCH/H



MN 1790 1 - 10

©

T E C H C OM


GSM and SBS fundamental aspects concerning RadioNetwork Planning: BCCH Multiframe

GSM and SBS fundamental aspects concerning RadioNetwork Planning: BCCH Multiframe

F S F S F S F S F S IB C C C D0 D1 D2 D3 A0 A1

F S F S F S F S F S IB C C C D0 D1 D2 D3 A2 A3

RR RRRRRRRRRRRRRRRRRRRRRRR RRD3 A2 A3 D0 D1 D2

RR RRRRRRRRRRRRRRRRRRRRRRR RRD3 A0 A1 D0 D1 D2

F - FCCH - Frequency Correction Ch.

S - SCH - Synchronization ChannelB - BCCH - Broadcast Control Channel

C - CCCH - Common Control Channel

D - SDCCH - Stand alone Dedicated Control Ch.

A - SACCH - Slow Associated Control Ch.R - RACH - Random Access Channel

I - idle

uplink

downlink

51 TDMA multiframe



MN 1790 1 - 11

©

T E C H C OM


GSM and SBS fundamental aspects concerning RadioNetwork Planning: SDCCH Multiframe

GSM and SBS fundamental aspects concerning RadioNetwork Planning: SDCCH Multiframe

B0..B7 SDCCH subslots

A0..A7 SACCH subslots

51 TDMA multiframe

downlink

B0 B1 B2 B3 B4 B5 B6 B7

B0 B1 B2 B3 B4 B5 B6 B7

A0 A1 A2 A3

A4 A5 A6 A7

uplink

B0 B1 B2 B3 B4 B5 B6 B7

B0 B1 B2 B3 B4 B5 B6 B7

A0

A1 A2 A3

A5 A6 A7

A4



MN 1790 1 - 12

©

T E C H C OM


GSM and SBS fundamental aspects concerning RadioNetwork Planning: TCH Multiframe

GSM and SBS fundamental aspects concerning RadioNetwork Planning: TCH Multiframe

T T T T T T T T T T T T A T T T T T T T T T T T T -

T t T t T t T t T t T t A t T t T t T t T t T t T a

26 TDMA frame = 120 ms

uplink / downlink: Traffic Channel (TCH/F)

uplink / downlink: Traffic Channel (TCH/H)

T - TCH - Traffic Channel

t - TCH - Traffic Channel

A - SACCH - Slow Associated Control Channel

a - SACCH - Slow Associated Control Channel



MN 1790 1 - 13

©

T E C H C OM


dummy burst

training sequence26

encrypted bits57

S1

TB3

encrypted bits57

S

1

TB3

fixed bit pattern

142

TB

3

TB

3

GP8.25

GP8.25

normal burst

frequency correction burst

fixed bits → always 0TB

3

TB

3GP

8.25

synchronization burst

training sequence64

information39

TB3

information

39

TB3

GP8.25

access burst

training sequence41

TB8

information36

TB3

GP68.25

GSM and SBS fundamental aspects concerning RadioNetwork Planning: Burst Types

GSM and SBS fundamental aspects concerning RadioNetwork Planning: Burst Types



MN 1790 1 - 14

©

T E C H C OM


GSM and SBS fundamental aspects concerning RadioNetwork Planning: RXQUAL

GSM and SBS fundamental aspects concerning RadioNetwork Planning: RXQUAL

Assumed value 18.1%12.8 % < BERRXQUAL = 7

Assumed value 9.05%6.4 % < BER < 12.8 %RXQUAL = 6

Assumed value 4.53%

3.2 %

< BER < 6.4%

RXQUAL = 5





Assumed value 0.14%BER < 0.2 %RXQUAL = 0

RXQUAL (Received signal quality, see GSM 05.08)



MN 1790 1 - 15

©

T E C H C OM


GSM and SBS fundamental aspects concerning RadioNetwork Planning: RXLEV

GSM and SBS fundamental aspects concerning RadioNetwork Planning: RXLEV

RXLEV (Received signal level, see GSM 05.08)

greater than – 48 dBmRXLEV = 63

– 49 dBm to – 48 dBmRXLEV = 62

......



Less than – 110 dBmRXLEV = 0



MN 1790 1 - 16

©

T E C H C OM


GSM and SBS fundamental aspects concerning RadioNetwork Planning: SQI

GSM and SBS fundamental aspects concerning RadioNetwork Planning: SQI

SQI (Speech quality index, Ericsson defined (and patented) parameter, see Pat. No. WO-9853630)

Value ranges:

-20 dBQ to 30 dBQ for Enhanced Full Rate (EFR) speech coders

-20 dBQ to 21 dBQ for Full Rate (FR) speech coders

badSQI ≤ 0

good1 ≤ SQI ≤ 19

Very good for FR / EFR20 ≤ SQI ≤ 21 / 30

Perceived speech qualitySQI values



MN 1790 1 - 17

©

T E C H C OM


GSM and SBS fundamental aspects concerning RadioNetwork Planning: BSIC / LAI

GSM and SBS fundamental aspects concerning RadioNetwork Planning: BSIC / LAI

BSIC (Base Station Identity Code, see GSM 03.03 and GSM 05.08)

BSIC = NCC – BCCNCC = Network colour code (range: 0 – 7)

BCC = Base station colour code (range: 0 – 7)

LAI (Location are Identification, see GSM 03.03)

LAI = MCC – MNC – LAC

MCC = Mobile country code

MNC = Mobile network codeLAC = Location area code (range: 0-65535)



MN 1790 1 - 18

©

T E C H C OM


GSM and SBS fundamental aspects concerning RadioNetwork Planning: ARFCN

GSM and SBS fundamental aspects concerning RadioNetwork Planning: ARFCN

RFC (Radio frequency carrier , see GSM 05.01 and GSM 05.05)

The carrier frequency is related to the absolute radio frequency channel number (ARFCN) as given inthe following table:

1805-1880 MHz

F(DL) = F(UL) + 95512 ≤ n ≤ 885

1710 – 1785 MHz

F(UL) = 1710.2 + 0.2 x(n-512)

DCS 1800 band

925 - 960 MHz

F(DL) = F(UL) + 450 ≤ n ≤ 124975 ≤ n ≤ 1023

880 – 915 MHz

F(UL) = 890 + 0.2 x nF(UL) = 890 + 0.2 x (n-1024)

Extended GSM

900 band(E-GSM band)

935 – 960 MHz

F(DL) = F(UL) + 451 ≤ n ≤ 124

890 – 915 MHz

F(UL) = 890 + 0.2 x n

Primary GSM

900 band

(P-GSM band)

DL-frequencies ARFCN valuerange

UL-frequenciesFrequency band



MN 1790 1 - 19

©

T E C H C OM


438 = n = 511Fl(n) = 747.2 +

0.2*(n-438)

30777 - 792747 - 762GSM 750

921 - 925

488.8 – 496

460.4 – 467.6

869 – 894

1930-1990

1 805 - 1 880

925 – 935

935 - 960

Downlink freq.(MHz)

45

10

10

45

80

95

45

45

Duplex dis-tance (MHz)

Fl(n) = 890 +

0.2*(n-1024)

Fl(n) = 479 +

0.2*(n-306)

Fl(n) = 450.6 +

0.2*(n-259)

Fl(n) = 824.2 +

0.2*(n-128)

FI(n) = 1850.2 +

0.2*(n-512)

1710.2 +

0.2*(n-512)

Fl(n) = 890 +

0.2*(n-1024)

Fl(n) = 890 +

0.2*n

259 = n = 293450.4 – 457.6GSM 450

955 = n = 973876 - 880Railway GSM

306 = n = 340478.8 – 486GSM 480

128 = n = 251824 – 849GSM 850

512 = n = 8101850-1910GSM 1900

512 = n = 8851 710 - 1785GSM 1800

975 = n = 1023880 – 890GSM 900

Extended band

1 = n = 124890 – 915GSM 900

Primary band

Numbering of ARFC (Uplink freq.)Uplink freq.(MHz)

Frequency band

GSM and SBS fundamental aspects concerning RadioNetwork Planning: Frequency Bands

GSM and SBS fundamental aspects concerning RadioNetwork Planning: Frequency Bands



MN 1790 1 - 20

©

T E C H C OM


GSM and SBS fundamental aspects concerning RadioNetwork Planning: BA

GSM and SBS fundamental aspects concerning RadioNetwork Planning: BA

Neighbour cell list (BA, BCCH Allocation, see GSM 04.08 and GSM 05.08)

The BA is a list of ARFCN which are used in the neighbour cells.GSM distinguishes the BA (BCCH) and the BA (SACCH).

The carriers to be monitored by the MS in idle mode (for cell reselection) are given by the BA

(BCCH).

The carriers to be monitored by the MS while being in connected mode (TCH or SDCCH) are givenby the BA (SACCH).

The parameter BA-IND discriminates between measurement results related to different BA (BA(BCCH) and BA (SACCH)).

The parameter BA-USED shows the value of the BA-IND used for BCCH allocation.



MN 1790 1 - 21

©

T E C H C OM


BTSone BS20, BS21, BS22, BS60, BS61

BTSplus BS40, BS41, BS240, BS241

Special types BS82 E-Micro-BTS

BS242 Pico-BTS

Naming convention:

last digit: 0 = indoor 1 = outdoor

2 = special purpose

first digit(s) number of TRX supported

GSM and SBS fundamental aspects concerning RadioNetwork Planning:

SIEMENS BASE STATION Types

GSM and SBS fundamental aspects concerning RadioNetwork Planning:

SIEMENS BASE STATION Types



MN 1790 1 - 22

©

T E C H C OM


BS-60 BS-61

BS-20 BS-21 BS-22

GSM and SBS fundamental aspects concerning RadioNetwork Planning: BTSone

GSM and SBS fundamental aspects concerning RadioNetwork Planning: BTSone



MN 1790 1 - 23

©

T E C H C OM


BS241BS240BS40 BS41

GSM and SBS fundamental aspects concerning RadioNetwork Planning: BTSplus




MN 1790 1 - 24

©

T E C H C OM


BS240 XL

More carriers per rack than ‚normal‘ BS240





MN 1790 1 - 25

©

T E C H C OM


BS82E-Micro-BTS

4 carriers per cabinet in Dual carrier unitsBuilt-in antenna or external antenna

GSM and SBS fundamental aspects concerning RadioNetwork Planning: Special BTS Types




MN 1790 1 - 26

©

T E C H C OM


Server rack

BS242 Pico-BTS

Up to 24 carrier agents at remote locations

Carrier Agent





MN 1790 1 - 27

©

T E C H C OM


BS240 XS

Up to 6 carriers with small rack

and BTSplus Hardware

GSM and SBS fundamental aspects concerning RadioNetwork Planning: BS240 XS

GSM and SBS fundamental aspects concerning RadioNetwork Planning: BS240 XS



MN 1790 1 - 28

©

T E C H C OM


Base

stationcontroller

BSC

Transcoding

and Rate

AdaptationUnit

TRAU

GSM and SBS fundamental aspects concerning RadioNetwork Planning: BSC and TRAU

GSM and SBS fundamental aspects concerning RadioNetwork Planning: BSC and TRAU



MN 1790 1 - 29

©

T E C H C OM


3500

3200

1536

> 240

72

32

200

250

500

BR6.0

4000

3200

2880

> 240

120

36

200

400

900

BR7.0

200020001000Switch.

Cap. (Erl)

320032001000Process.Cap. (Erl)

128n. a.n. a.GPRS TS

48-112112112LAPD

464636PCMx

202012TRAU

10010060BTSE

150150120Cells

250250120TRX

BR5.5BR5.0BR4.0Capacity

GSM and SBS fundamental aspects concerning RadioNetwork Planning: Capacity Numbers

GSM and SBS fundamental aspects concerning RadioNetwork Planning: Capacity Numbers



MN 1790 1 - 30

©

T E C H C OM


Planning Objectives & Principle Planning StepsPlanning Objectives & Principle Planning Steps

General planning objectives:

To realize service(s) with

• maximum coverage

• maximum capacity

• maximum Quality of Service (QoS)

• minimal interference

at minimum costs



MN 1790 1 - 31

©

T E C H C OM



Principle planning steps

1) Basic planning data acquisition (data about: expected traffic load and planned service area)

nominal cell plan

2) Terrain data acquisition & installation of a digital terrain database (including topographical and

morphological data) into a planning tool

3) Coarse coverage prediction and initial site determination for a first site selection process using

the digital terrain data and standard propagation models

4) Site survey and site selection

5) Survey measurements (to fine tune the propagation models)

6) Detailed network design (to determine “final” network structure: Number and configuration ofBTS, BSC, TRAU; needed antennas and transmission lines; frequency plan; future evolution

strategy)

7) Transmission planning



MN 1790 1 - 32

©

T E C H C OM



Nominal Plan

Detailed Plan

Modification &

Optimization



MN 1790 1 - 34

©

T E C H C OM


Site Survey & Site InvestigationSite Survey & Site Investigation

Site survey and site investigation:

• Selection of the sites to be used from alternative locations (if available)

• Contract for site leasing exists?

• Adaption of the cell plan to the real locations that are used (nominal positions must be replaced

by the real ones)

• Antenna installation possible?

• Antenna separation possible?

• Predicted antenna height realistic?

• First Fresnel Zone free of obstacles (for the nearest 50 to 100 meters)?

• Enough place for the radio (BTS and microwave) equipment, the battery backups, ...?

• Find out from where the primary power can be taken

• Find antenna cable path and measure required cable length

• Find out how the transport network can be brought into the site

• Sketch the earthing and lightning protection system

•...



MN 1790 1 - 36

©

T E C H C OM


Antenna PatternsAntenna Patterns

Antenna pattern:

The (real) distribution of the radiated power as function of the direction is usually displayed inhorizontal and/or vertical antenna radiation patterns. For these diagrams, usually polar coordinates graduated in decibels (dB) are used. Since an antenna is a passive component, due

to the conservation of energy an increase of the radiated power in one direction will reduce theradiated power in an other direction. For sector antennas, the main lobe in the front direction

should be maximised whereas the back lobe should be minimised.

The sector width (e.g. 120° sector) should not be confused with the half power beam width. For example, often 60° – 65° half power beam width antennas are used to realise 120° sectors.



MN 1790 1 - 37

©

T E C H C OM


Antenna PatternsAntenna Patterns

Antenna patterns display the distribution of radiated energy in the horizontal and vertical direction:

horizontal pattern vertical patternelectrical

down-tilted

antenna



MN 1790 1 - 38

©

T E C H C OM


Antenna ParametersAntenna Parameters

• Frequency range

• Polarization• Gain

• Half-power beam width

• Electrical tilt

• Front to back ratio

• Impedance

• VSWR and return loss

• Maximum power per input

• Input connectors

• Connector position

• Dimensions (height, width, depth)

• Weight

• Wind load (frontal, lateral, rearward)

• Maximum wind velocity



MN 1790 1 - 39

©

T E C H C OM



Example values for a sector antenna:

200 km/hMaximum wind velocity

460 N, 300 N, 1020 N at 150 km/hWind load (frontal, lateral, rearward)

12 kgWeight

2574 / 258 / 103 mmDimensions (height, width, depth)

RearsideConnector position

7/16“ femaleInput connectors

500 W (at 50oC ambient temperature)Maximum power per input

< 1.3VSWR and return loss

50 OhmImpedance

> 23 dBFront to back ratio

6o electrical downtiltElectrical tilt

H-plane: 90o / E-plane: 6.5oHalf-power beam width

17dBiGain

VerticalPolarization

870 - 960 MHzFrequency range



MN 1790 1 - 40

©

T E C H C OM



Half power beam width:

The opening angle between the points where the radiated power is 50 % (3 dB) lower than the

power transmitted in the main direction is called the half power beam width.

Antenna gain:

The gain of an antenna is given either in dBi (with respect to an ideal, isotropic antenna) or in dBd

(with respect to a dipole antenna):

Gain (dBi) = Gain (dBd) + 2.15 dB

Antenna tilt:

Two different tilt types can be distinguished: electrical tilt and mechanical tilt.

Mechanical tilt is achieved by corresponding mounting of the antennas using special mountingdevices.

Electrical tilt is a built-in function of an antenna. Either an antenna has or does not has thisfunction. Usually an electrical down-tilted antenna has just one (fixed) electrical (down)-tilt but

there also exist antennas where the electrical (down)-tilt is settable.

In addition to an electrical tilt also a mechanical tilt can be applied. The effective tilt is the sum of

both tilts.



MN 1790 1 - 41

©

T E C H C OM



Voltage Standing Wave Ratio (VSWR):

The VSWR-ratio is a measure for the reflected output power. If the impedance of the antenna

does not match to the impedance of the feeder, the output power is reflected to the transmitter. As

a consequence the transmitter performance and the radiated power will be reduced. The closer

the VSWR-ratio is to 1, the lower the reflected output power.

Polarisation:

The polarisation plane is given by the electrical field vector. Usually antennas are vertically or

cross polarised.



MN 1790 1 - 42

©

T E C H C OM


Antenna Tilt (Mechanical and/or Electrical)Antenna Tilt (Mechanical and/or Electrical)

Mechanical downtilt:

Advantages:Downtilt adjustable, simple method (requires only some mounting hardware: „downtilt kit“)

Disadvantages:

Downtilt angle varies for different azimuth directions

Horizontal half-power beam width increases with downtilt angle

Gain reduction depending on azimuth direction

Electrical downtilt:

Advantages:

Downtilt angle is constant for all azimuth directions

Horizontal half-power beam width does not increase with downtilt angle

Disadvantages:

Downtilt angle is fixed



MN 1790 1 - 43

©

T E C H C OM


Antenna Tilt (Mechanical and/or Electrical)Antenna Tilt (Mechanical and/or Electrical)

Adjustable electrical downtilt:

Advantages:Downtilt adjustable

Downtilt angle is constant for all azimuth directions

Horizontal half-power beam width does not increase with downtilt angle

Optimum downtilt angle:

• Must be calculated

• Depends on the surrounding

• Field strength reduction in the horizontal direction is maximum if minimum between main

and first upper side lobe is pointing towards horizon



MN 1790 1 - 44

©

T E C H C OM


(Effective) Antenna Height(Effective) Antenna Height

Several methods to calculate effective antenna height:

• Absolute calculation method:

Effective height = Base station antenna height above ground

Heff = HBS

•Relative calculation method:

Heff = HBS + HTHatBS – HTHatMS if HTHatBS > HTHatMS

Heff = HBS if HTHatBS ≤ HTHatMS

HBS = Base station antenna height above ground at base station site

HTHatBS = Terrain height above sea level at base station site

HTHatMS = Terrain height above sea level at mobile station site

• Averaged calculation method:

Effective height = Base station antenna height above the averaged terrain height of the

prediction area



MN 1790 1 - 46

©

T E C H C OM


Antenna CablesAntenna Cables

The radio planner has to know the exact loss of the system:

Jumper cable / Feeder cable / Connectorswhich must be specified in the link budget.

Cables are characterized by:

• Cross-section and length

• Loss in [dB/m]

• Impedance

• Frequency range

• Reflection factor

• 3rd order inter-modulation product

• Minimum bending radius (for repeated bending)

Hints concerning the selection of antenna cables:

The power dissipation increases exponentially with the cable length. Thick cables have lowerlosses, but larger bending radii and they are more expensive.

Avoid unnecessary long cables!



MN 1790 1 - 47

©

T E C H C OM


Antenna cables and IntermodulationAntenna cables and Intermodulation

What is intermodulation (IM)?

• Occurrence of frequencies different from the transmitted frequencies in the spectrum

Example: Two frequencies are used: f 1 = 942.6 MHz, f 2 = 945.6 MHz

Additionally frequency f IM = 936.6 MHz is measured

• Responsible for Intermodulation are non-linearities in the transmission path

Example: non-linear amplifier

dirty surfaces

oxidized contactstreated surfaces, e.g. antennas on printed circuit boards



MN 1790 1 - 48

©

T E C H C OM



Order of an Intermodulation Product (IMP)

•IM-Frequencies are related to the transmitted frequencies by sums and differences:

f IM = | n * f 1 ± m * f 2 |

Order O of IM-Product is

O = n + m

Examples:

far away from f 1 or f 242 * f 1 ± 2 * f 2

close to f 1 and f 253 * f 1 - 2 * f 2

close to f 1 and f 232 * f 1 - 1 * f 2

far away from f 1 or f 221 * f 1 - 1 * f 2

remarkorder n,m

Odd orders of IMP are close to the original frequencies!



MN 1790 1 - 49

©

T E C H C OM



Why can Intermodulation Products be dangerous?

IMP can be located in a frequency band where they interfere!

Example 1 (Extended GSM, f 1 = 942.6 MHz, f 2 = 945.6 MHz):

948.61 * f 1 - 2 * f 2

951.62 * f 1 - 3 * f 2

954.63 * f 1 - 4 * f 2

957.64 * f 1 - 5 * f 2

930.65 * f 1 - 4 * f 2

4 * f 1 - 3 * f 2

3 * f 1 - 2 * f 2

2 * f 1 - 1 * f 2

n,m

933.6

936.6

939.6

f IM [MHz]

Frequency

960 MHz925 MHz



MN 1790 1 - 50

©

T E C H C OM



Why can Intermodulation Products be dangerous?

IMP can be located in a frequency band where they interfere!

Example 2 (Extended GSM, f 1 = 933 MHz, f 2 = 955.6 MHz):

978.21 * f 1 - 2 * f 2

4 * f 1 - 3 * f 2

3 * f 1 - 2 * f 2

2 * f 1 - 1 * f 2

n,m

865.2

887.8

910.4

f IM [MHz]

915 MHz880 MHz Freq.960 MHz925 MHz



MN 1790 1 - 51

©

T E C H C OM


Antenna Near Products: OverviewAntenna Near Products: Overview

Antenna near products: Antenna combiners

Receiver modules Additional equipment

Equipment depends on base station type:

BTSone BS20, BS21, BS22, BS60, BS61BTSplus BS40, BS41, BS240, BS241, BS240XL

Specific solutions:BS82

BS242

BS240XS



MN 1790 1 - 53

©

T E C H C OM


Antenna Near Products: CombinersAntenna Near Products: Combiners

Tasks of combiners:

reducing amount of antenna for transmitting

combining concepts: combining on airhybrid couplers

filter combiners

duplex function for using the antenna in RX path



MN 1790 1 - 55

©

T E C H C OM


Antenna Near Products: DUCOMAntenna Near Products: DUCOM

DUCOM (DUKIT) 2:1

DUKIT 2*1:1

DUCOM 4:1

RX-FIL

TX-FILIsolator

VSWR

RX-FIL

TX-FILIsolator

VSWR

TESTOUT0

RX0

TX 0

RX1

TX1

T E S TOUT 1

ANT0

ANT1

RX-FIL

TX-FIL

VSWR

RX-FIL

TX-FIL

VSWR

TESTOUT0

RX 0

TX 0

RX 1

TESTOUT1

ANT 0

ANT1

TX 1

TX 2

TX 3

3 dBHybrid

3 dB

Hybrid

Iso la to r

Iso la to r

Iso la to r

Iso la to r

RX-FIL

TX-FIL Isolator

VSWR

Isolator

VSWR

TESTOUT0

RX0

TX0

RX 1

TX 1

TESTOUT1

ANT0

ANT1

RX-FIL

RX-FILRXdiv0 ANTdiv0

RXdiv1 ANTdiv1

RX-FIL

TX-FIL



MN 1790 1 - 56

©

T E C H C OM


Antenna Near Products: FICOMAntenna Near Products: FICOM

ANT OUT

FICOM Base 2:1

TX 2 TX 3TX 0 TX 1

VSWR

TX4

FICOM Expansion 2:1 FICOM Expansion 1:1



MN 1790 1 - 57

©

T E C H C OM


Antenna Near Products: Combiner Losses BTS1Antenna Near Products: Combiner Losses BTS1

1.82.0HYCOM 1:1

3.93.7HYCOM 2:1

7.66.5HYCOM 4:1

2.82.8DUKIT

2.52.5DUCOM 2:1

4.93.3FICOM 6:14.23.0FICOM 4:1

3.52.4FICOM 2:1

5.75.7DUCOM 4:1

Loss for DCS/PCS (dB)Loss for GSM (dB)Combiner type

Combiner losses for BTS one:



MN 1790 1 - 63

©

T E C H C OM


Antenna Near Products: Combiner Losses BTSplusAntenna Near Products: Combiner Losses BTSplus

5.35.3DUAMCO 2:1

8.58.5DUAMCO 4:1

2.52.5DUAMCO 2:2

5.84.2FICOM 8:1

4.63.7FICOM 6:1

4.23.2FICOM 4:1

3.72.7FICOM 2:1

8.98.9DUAMCO 8:2

5.75.7DUAMCO 4:2

Loss for DCS/PCS (dB)Loss for GSM (dB)Combiner type

Combiner losses for BTS plus and BS82:



MN 1790 1 - 64

©

T E C H C OM


Antenna Near Products: RX SensitivityAntenna Near Products: RX Sensitivity

BTSone: -109 dBm at rack input

BTSplus: - 116 dBm with TMA

BS82: = -110 dBm

BS242:-88 dBm (GSM900), -95 dBm (GSM1800/GSM1900)



MN 1790 1 - 65

©

T E C H C OM


Antenna Near Products: Receiver ModulesAntenna Near Products: Receiver Modules

Tasks of receiver modules:

amplifying received signals

different concepts: receiver module in BTS rack

Tower mounted amplifiers

splitting of received signal for TRX equipment

comparison of different signals (RX diversity)



MN 1790 1 - 69

©

T E C H C OM


Antenna

Rx Tx

LNA

TMA

Rx Tx

Triplexer Encoder

DUAMCO/DIAMCO

Antenna Near Products: TMAAntenna Near Products: TMA



MN 1790 1 - 70

©

T E C H C OM


19.5 (without TMA)19.5 (without TMA)DIAMCO

19.5 (without TMA)19.5 (without TMA)DUAMCO

25.525.0TMA

RX Gain for DCS/PCS (dB)RX Gain for GSM (dB)Equipment type

Gain and loss of various BTS plus equipment:

0.60.4TMA

TX Loss for DCS/PCS (dB)TX Loss for GSM (dB)Equipment type

Antenna Near Products: ValuesAntenna Near Products: Values



MN 1790 1 - 71

©

T E C H C OM


Antenna Near Products: Additional EquipmentAntenna Near Products: Additional Equipment

Additional equipment: DULAMO

D4EMHPDUDUBIAS

DIPLEXER



MN 1790 1 - 72

©

T E C H C OM


Antenna Near Products: DULAMOAntenna Near Products: DULAMO

DULAMO for BTSone:

• Allows to use TMA with BTSone

• Works with HYCOM, DUCOM and FICOM



MN 1790 1 - 73

©

T E C H C OM


Antenna Near Products: D4EMAntenna Near Products: D4EM

D4EM for BTSone:

•Allows to use 2 DUCOM 2:1 for one cell

with 4 TRX

•Reduced combiner loss



MN 1790 1 - 75

©

T E C H C OM


Antenna Near Products: DUBIASAntenna Near Products: DUBIAS

FICOM

HPDU

DUBIAS

TMA

TX/RX antenna

DIAMCO

TMA

CU1 CU8 RX1 RX8

BIAS-TEE for HPDU: DUBIAS

Allows use of HPDU with TMA

DUBIAS technical data

<= 0.2 dB<= 0.2 dBTXLoss (dB)

<= 0.7 dB<= 0.7 dBRXLoss (dB)

DCS/PCSGSM



MN 1790 1 - 76

©

T E C H C OM


Antenna Near Products: DIPLEXERAntenna Near Products: DIPLEXER

DIPLEXER

Allows use of one feeder cable or even

one antenna for GSM900

and GSM 1800/1900

AntennaCombiner

900

DIPLEXER

AntennaCombiner

1800

DIPLEXER

TX/RX ant. TX/RX ant.

1700 - 2000 MHz800 - 1000 MHz

800 - 1000 MHz 1700 - 2000 MHz

Dimensions:

274mm * 126mm * 51mm

Insertion loss:

0,15 dB (800 - 1000 MHz)0,25 dB (1700 - 2000 MHz)

Base Station

Feeder cable



MN 1790 1 - 77

©

T E C H C OM


Antenna Near Products: Specific SolutionsAntenna Near Products: Specific Solutions

BS82 – Enhanced Micro-BTS: Solution without DUAMCO

Output Power: 14 W



MN 1790 1 - 81

©

T E C H C OM


ExercisesExercises

1) What are the units for:

- the power?

- the level?

- the loss?

- the gain?

2) Write down the formula which expresses the level as function of the power.

3) Write down the formula which expresses the power as function of the level.

4) Consider a device with 10 mW output power and 1 W input power.What is the amplification/attenuation in dB?

5) Consider a device with 100 W output power and 1 W input power.

What is the amplification/attenuation in dB?



©

T E C H C OM


ExercisesExercises

6) Fill in the following table:

“Factor of: ““+/- 10 dB”

60 dBm

50 dBm

40 dBm

30 dBm

20 dBm

10 dBm

0 dBm

-10 dBm

...

-90 dBm

-100 dBm

-110 dBm

P [W]L

01 mn1790 introduction

Documents