Multilayered Communication Network Solution

Shaurov DharDepartment of Electrical Engineering & Computer Science, North South University

Plot 15, Block B, Bashundhara, Dhaka 1229, Bangladeshshaurov@gmail.com

Abstract - In the present climate of growth in telecommunication applications, wireless infrastructure providers are under continuous pressure to exploit the limited radio spectrum as efficiently as possible. In this context, Multilayered Communication Network Solutions are increasingly being cited as having an important role to play in future systems and applications. Such platforms may be integrated with Communication Satellites, Mini, Micro or Nano Satellites, High Altitude Platform, Radar & Satellite Ground Base Station and TV / Radio / WIFI / MAX / Mobile Base Stations. Our Group Project reviews some of the recent development of Multilayered Communication Network Solution and Platforms from which future communication services could be supported.

Index Terms - High Altitude Platform, Communication Satellite, Mini / Micro / Nano Satellite

1. INTRODUCTIONWireless communication services are typically provided by

terrestrial and satellite systems. The successful and rapid deployment of both wireless networks has illustrated the growing demand for broadband mobile communications. These networks are featured with high data rates, reconfigurable support, dynamic time and space coverage demand with considerable cost. Terrestrial links are widely used to provide services in areas with complex propagation conditions and in mobile applications. Satellite links are usually used to provide high speed connections where terrestrial links are not available. In parallel with these well established networks, a new alternative using aerial High Altitude Platforms (HAPs) has emerged and attracted international attentions. Our proposed Multilayered Communication Network Solution is integrated with Communication Satellites, Small Satellites and High Altitude Platforms.

2. HIGH ALTITUDE PLATFORMA High Altitude Platform (HAP) is airships or planes which

can support payloads to deliver a range of services: principally communications and remote sensing. A HAP differs from other aircraft in the sense that it is specially designed to operate at a very high altitude and is able to stay there for months. The new generation of HAPs, however, will expand this period to several years. These platforms are reusable and positioned at stratospheric altitudes, from 20 to 50 km approximately.

A High Altitude Platform may seem a very simple concept, with an enormous potential. In the history of science and technology, there have been situations where very simple concepts have changed the world; the creation of the wheel is a clear example of this. Often, these inventions have come to life as a result of specific human needs which must be satisfied. Since the invention of radio waves in the nineteenth century, communication systems have become a priority, not only for military use, but also for civilian applications, with an increasing interest in having more demanding services from the users. This situation has motivated scientists and researchers to seek novel and innovative methods to provide broadband services throughout the wireless channel, serving a larger number of users and improving spectral efficiency. The potential of HAP is dawning on us slowly. The acronym HAP is a term standing for .high altitude platform stations, also known as stratospheric repeaters. HAP is the name of a technology for providing wireless narrowband and broadband telecommunication and broadcasting services. [1]

2.1. About The PlatformThe International Telecommunications Union (ITU)

published a report in 1998 which outlines HAPS as a new technology, entitled “High Altitude Platform Stations: an opportunity to close the information gap” [ITU-Q/2, 98]. The ITU defines HAP as a term referring to balloons or high altitude aircraft that can be used to provide communication services [ITU-F.1399, 01], [ITU, 03]. A HAP, in essence, is a radio relay in the sky.

The ITU has described HAPS as “representing a new and long anticipated technology that can revolutionize the telecommunication industry”. It is the next generation of wireless communications infrastructure that can make efficient use of radio spectrum resources, demonstrating greater system capacity, higher transmission quality and lower operating risk with the option to upgrade payload equipment at all times.

The HAPs are seen as a middle ground between the terrestrial and satellite cases, and aims at exploiting potential benefits of intermediate altitudes between those used by the terrestrial and satellite technologies to provide broadband services to users, maximizing capacity and spectral efficiency, with a reduction in cost and complexity. [2]

Fig. 1. Images of various High Altitude Platforms (HAPs)

3. ADVANTAGES: CLOSING THE “DIGITAL DIVIDE”HAP's proximity to the Earth will allow several

transmission technologies to operate on the same platform including TV and radio, broadcast, mobile telephony, VoIP, remote sensing and local GPS. HAPs can act as base stations or relay nodes, which may be effectively regarded as a very tall antenna or a Low Earth Orbit (LEO) satellite.

• Rapid deployment - HAP's technologies can be deployed, redeployed and upgraded rapidly.

• Low Cost - HAP's platforms are expected to be much cheaper than existing and planned infrastructures

(terrestrial wire line and wireless and satellite systems).

• Environmentally friendly - HAPS are sustainable and environmentally friendly. They use redeployable components and modules. With their low energy exhaust free solar propulsion systems, they can be deployed over urban areas.

• Mobility - HAPs can also provide telecommunication services or the backbone for terrestrial networks in remote areas or in disaster affected areas.

Another important benefit of HAP systems over satellites is the shorter delay that a signal travelling from a HAP to a subscriber on the ground, compared with that from a satellite link to ground. For example, for a low Earth orbit (LEO) Satellite at 1400 km altitude, the one-way delay is about 5 ms, whereas for a HAP located at 25 km of altitude, this delay is only 0.083 ms. [2]

3.1. Facts & Features• The HAPs can coverage can reach a region up to

500km in diameter.

• Covered area has a cellular architecture for frequency reuse.

• The HAPs can be equipped with a spot beam antenna for Wimax/4G and digital broadcasting.

Fig. 2. Showing some Facts & Features of HAPs

4. APPLICATION & SERVICESHigh altitude platform stations can be considered to be a

hybrid architecture, having some areas in common with terrestrial communications, particularly the so-called fixed wireless access (FWA), and also having similarities to satellites in terms of power constraints and general network architecture. So far, the ITU-R has regulated only fixed

wireless services for HAPS [ITU-F1399, 01], [ITU-F592, 02]. There are a number of possible application areas for HAPS. Potential areas are mainly within the telecommunications industry and other services.

4.1. ICT Application & ServicesHAPs have been proposed to deliver modern broadband

services, i.e. high-speed internet, High-Definition Television (HDTV), Local Multi Point Distribution (LMDS), Multi Channel Multimedia Distribution Service (MMDS), and Wireless Interoperability for Microwave Access (WiMAX). All these services require wide bandwidth and high capacity. Generally these applications can be thought to equip base stations with technologies based on well established terrestrial system onboard, but they have new challenges, e.g. cell structures, handover controls and dynamic channel assignment.

BWA services operate in the higher frequency bands, i.e. the mm-wave bands at several GHz, to provide the required radio frequency bandwidth allocation. The frequency bands allocated for LMDS in most countries in the world are around 30 GHz. ITU has assigned frequency bands of 47-48 GHz to HAPs worldwide. The 28-31 GHz bands have also been assigned to HAP in some regions.

HAPs may be one of the most important infrastructures for International Mobile Telecommunications (IMT-2000) 3G service, since HAPs can offer new means to provide IMT-2000 service with a less number of network infrastructures. IMT-2000 standard has included provision for base-station deployment from HAPs and still needs further study before the deployment from HAPs in the areas of cell planning and antenna development. Employing access techniques such as Code Division Multiple Access (CDMA), Wideband-CDMA (W-CDMA) based IMT-2000 and CDMA based Universal Mobile Telecommunications System (UMTS) from HAPs to provide 3G communications have been examined. [3], [4]

Data traffic• LAN & WAN interconnect • Voice, data and video• High speed data • WIFI / MAX• Backhauling of WIFI spots

Broadcast • TV & TV on demand • Digital Radio • Video on demand • Interactive TV (iTV)

Telecommunication • Fixed & Mobile convergence • Mobile services for 2, 3 and 4G• Interoperability of telecom infrastructures • Video conferencing • City networks

4.2. Disaster ManagementDisaster can be happen any where at any time. Any action

related to the disaster management has to be done in a quick and proper manner. At the very first chance, immediate survey over the area must be done to get as much as possible data and information concerning the disaster. High Altitude Platform can effectively use for flood detection, seismic monitoring, and remote sensing as well as for disaster management.

HAPs can support country in protecting persons, reconnaissance, providing emergency communications, forecasting, detecting natural disasters and supporting relief action.

Fig. 3. Arial images of Sendai's City Centre, Japan, Before and After the Quake and Tsunami

4.3. Surveillance, Intelligence and Border MonitoringHAPs will support users in monitoring and protecting

network systems (e.g. electricity, oil, gas, water, traffic networks and communication against sabotage etc.) and detecting damages and threats (e.g. to power plants, power lines, oil or gas pipelines, roads, railway lines, vehicles and communication systems).

One of the best example of a High Altitude Platform used for Surveillance and Security is RQ4 Global Hawk UAV used by the US Air Force. It has a service ceiling of 20 km and can stay in the air for continuous 36 hours. It carries a highly sophisticated sensor system including radar, optical, and infrared imagers.

Fig. 4. RQ4 Global Hawk UAV used by the US Air Force

5. FACILITIES IN BANGLADESH

5.1. Bangladesh Aerial Photography Service (BAPS)The Bangladesh Aerial Photography Service (BAPS)

allows a unique perspective on aerial photography. The Airship & Balloon is filled with Helium. A camera is suspended under the Remote Control Airship and photos are taken from the ground. In comparison to traditional aerial photography, the lower altitude of our environmentally friendly Remote Control Airship system allows for closer photo & video of the subject.

The Remote Control Airship offers ideal perspectives for residential and commercial photography, Aerial filming- plus a wide range of other applications ranging from Wild life filming, Environmental Research Work, Television, Security, Construction project, Roads and Traffic studies to Sporting events. [5]

5.1.1. The BAPS Offers• Aerial Filming• Industrial & Commercial Photography• Residential Photography• Wild Life Filming• Television Aerial Video• Construction Project Monitoring• Environmental Research Work• Roads and Traffic studies• Sporting events• Government• Weather• Education• Security• Site Surveys

Fig. 5. Airships and Camera used by Bangladesh Aerial Photography Service

Fig. 6. Low Altitude Arial Images by Bangladesh Aerial Photography Service

5.2. Bangladesh Space Research and Remote Sensing Organization (SPARRSO)

Bangladesh Space Research and Remote Sensing Organization (SPARRSO) is the national space research and exploration agency of Bangladesh. Established in 1980 as an autonomous multisectoral R & D organization of the Bangladesh government, SPARRSO has been the national focal point for peaceful applications of space science, remote sensing and the Geographic Information System in Bangladesh. It has been credited internationally for its research, surveys and monitoring in Bangladesh's agriculture sector. SPARRSO has been working in close collaboration with NASA of the United States, JAXA of Japan, CNES of France and CNSA of China. [6]

5.2.1. Applications and Services by SPARRSO

Agriculture• Estimation of Aman and Boro rice area and yields

Fisheries• Fisheries resource survey (water body mapping)• Delineation of potential fishing zone• Mapping of suitable site for shrimp farming

Water Resources & Hydrology• River course monitoring• Coastal zone dynamics• Monitoring of water-logging• Kaptai Lake study• Estimation of chlorophyll content

Forestry & Environment• Forest cover mapping• Monitoring of mangrove forestation• Assessments of deforestation and carbon emission• Timber volume inventory• Climate change impact studies

Agro & Hydro Meteorology• Weather & drought monitoring

Natural Calamities & Disaster Management• Cyclone monitoring• Flood mapping• Post-disaster damage assessments• Cartography• Thematic map generation• Digital cadastral mapping• Mapping of tea gardens• Drainage pattern mapping

Land use & Land cover• Coastal land zoning• Land use and land cover mapping

Oceanography• Delineation of maritime boundary

Urban Studies• Urban area mapping• Urban growth studies

5.2.1. SPARRSO Facilities

Satellite Ground Station• NOAA AVHRR Ground Station• FY-2E Satellite Ground Station

Laboratories• Digital Image Processing Laboratory• GIS Laboratory• Cartographic & Photographic Laboratory

Web Based Information Dissemination• http://www.sparrso.gov.bd

Fig. 7. Cyclone SIDR monitored by SPARRSO

5.3. Proposed Communication Satellite for BangladeshIn 2008, the Bangladesh Telegraph and Telephone Board

(BTTB) and the Better Business Forum proposed that Bangladesh should take up immediate measures to launch a communications satellite into space as it was essential for the development of the country's ICT sector. In April 2009, Prime Minister Sheikh Hasina revealed her government's intentions to have Bangladesh's first satellite in orbit by 2014. In November 2009, Bangladesh's government officially announced that in line with its vision of a "Digital Bangladesh", the country is planning to launch a telecommunications satellite into space by 2014 with assistance from other countries. [6]

Fig. 8. Communication Satellite for Bangladesh

6. DEVELOPMENTS

6.1. The CAPANINA ProjectCAPANINA project has explored the development of

broadband communications capability from aerial platforms or HAPs (High Altitude Platforms). CAPANINA will deliver low cost broadband communications services to small office and home users at data rates up to 120Mbit/s, a staggering

2000 faster than today's dialup modems and more than 200 times faster than a typical "wired" broadband facility.

Users in rural and other “hard to reach” areas has benefited thanks to the unique wide area, high capacity wireless coverage provided by HAPs. Additionally, use of "smart" roof top antennas on trains has provided the moving user with high speed internet connectivity. Stratospheric broadband fills the gap between satellite and terrestrial wireless technologies. Furthermore, without the need to dig up roads to lay new cables it is of particular relevance to rural, suburban and moving users. Whatever a user wants to do, be it browse the internet, download a movie or song, select video on demand or use any other bandwidth hungry application, HAP broadband delivery systems will ensure more cost effective availability to all. The CAPANINA project involves 14 partners and is partially funded by the European Union. [7]

Fig. 9. High speed internet connectivity on super first trains

6.2. STRATXX Near Space TechnologySTRATXX Near Space Technology AG is striving to

commercialize stratospheric communication platforms through the innovative application of advanced technologies based in Switzerland. STRATXX has developed a patented concept of commercial stratospheric services based on the latest sustainable technology in design, solar power, propulsion, avionics, materials, aerodynamics and other disciplines. STRATXX delivers the telecommunication industry airships (blimps) carrying communication antennas up to an altitude of 26'000 m. The stratospheric communication platforms carry Tetra Base stations, GSM base stations or WiMax platforms.

It’s airships carry high-definition 360° panoramic cameras for border control or perimeter protection. Infrared cameras deliver excellent video feeds to the ground station through a fiber cable. STRATXX HAPs can reinstall communication infrastructure after natural disasters (floods, earthquakes) within hours. [8]

The technical expertise and know-how acquired through the extensive research into stratospheric technologies has enabled an innovative contribution to several commercial fields, such as floating systems, gas and fuel tanks, tenso-structures, drag-

chutes, sails and any other structure requiring ultra-light, high-resistant and flexible material. Ultra light & tight super material used for our airship hulls is also capable to be used as antiballistic material. Body armour and car armour are made from this fibre. Bullet proof vests have been tested during autumn 2010.

Fig. 10. STRATXX’s X Station based network architecture

Fig. 11. 18'000m3 STRATXX X Station at Zeppelin Hangar in Friedrichshafen, Germany [9]

6.3. Indian Remote Sensing Satellites System (IRS)The Indian Remote Sensing (IRS) satellite system is one of

the largest constellations of remote sensing satellites in operation in the world today. The IRS programme commissioned with launch of IRS 1A in 1988 and presently includes ten satellites that continue to provide imageries in variety of spatial resolutions from better than one meter ranging upto 500 meters. IRS series of Earth Observation satellites are being built, launched and maintained by Indian Space Research Organisation

Following the successful demonstration flights of Bhaskara 1 and Bhaskara 2 satellites launched in 1979 and 1981,

respectively, India began to develop the indigenous Indian Remote Sensing (IRS) satellite program to support the national economy in the areas of agriculture, water resources, forestry and ecology, geology, water sheds, marine fisheries and coastal management.

Towards this end, India established the National Natural Resources Management System (NNRMS) for which the Department of Space (DOS) is the nodal agency, providing operational remote sensing data services. Data from the IRS satellites is received and disseminated by several countries all over the world. With the advent of high-resolution satellites new applications in the areas of urban sprawl, infrastructure planning and other large scale applications for mapping have been initiated. [10]

Fig. 12. Polar Satellite Launch Vehicle (PSLV) and OceanSat

The IRS system is the largest constellation of remote sensing satellites for civilian use in operation today in the world. With the launch of CARTOSAT 2A, the constellation now has eight satellites in operation IRS 1D, OCEANSAT 1, Technology Experiment Satellite (TES), RESOURCESAT 1, RESOURCESAT 2, CARTOSAT 1, CARTOSAT 2 and the latest CARTOSAT 2A and IMS 1. All these are placed in polar sun-synchronous orbit and provide data in a variety of spatial, spectral and temporal resolutions. [11]

6.4. Helios Prototype: The forerunner of 21st century solar powered "Atmospheric Satellites"

The Helios Prototype is a remotely piloted flying wing aircraft developed under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. The two primary goals of the Helios Prototype development are to demonstrate sustained flight at an altitude near 100,000 feet and flying non-stop for at least 24 hours, including at least 14 hours above 50,000 feet.

In 2001, the Helios Prototype achieved the first of the two goals by reaching an unofficial world-record altitude of 96,863 feet and sustaining flight above 96,000 feet for more than 40 minutes during a test flight near Hawaii. The aircraft is undergoing modifications and upgrades to enable it to

accomplish the flight endurance milestone, presently planned for late summer, 2003. [12]

The operational and technical ability to reach these two goals is critical for NASA's ERAST project. Through ERAST, many new propulsion, materials, control, instrumentation, and sensor technologies are being pioneered which could enable the development of a fleet of high-flying uninhabited aircraft that could conduct a wide variety of Earth and atmospheric science missions. Flying autonomously with mission-oriented payloads and instrumentation, these ultra-high flyers could carry out storm tracking studies, atmospheric sampling, spectral imaging for agricultural and natural resources monitoring, pipeline monitoring and also serve as relay platforms for telecommunications systems.

Fig. 13. Helios Prototype in flight

Developed by AeroVironment, Inc., of Monrovia, California, with the assistance of NASA's Dryden Flight Research Centre, the Helios Prototype is one of several remotely piloted aircraft that have been involved in NASA's ERAST project. It is an enlarged version of the Centurion flying wing, flown at Dryden in late 1998 to verify the handling qualities and performance of a lightweight all-wing aircraft of more than 200-foot wingspan. It was renamed the Helios Prototype to reflect its role as a forerunner of the eventual Helios production aircraft, which will be designed to fly continuously for up to six months at a time on science and commercial missions.

Part of a family of aircraft under the umbrella of ERAST (Environmental Research Aircraft and Sensor Technology), Helios was the culmination of the group’s solar-powered aircraft that, in August, 2001, reached an official world record altitude for a non-rocket powered aircraft, of 96,863 feet during a maximum-altitude flight.

NASA and AeroVironment officials see great potential for the use of high-altitude, long-endurance solar aircraft as platforms for a variety of Earth science experiments, telecommunications relay services, pipeline and border patrol monitoring, commercial agricultural imaging and military surveillance operations.

7. MULTILAYERED COMMUNICATION NETWORK SOLUTION ARCHITECTURE

Communication Satellite+

Mini / Micro / Nano Satellites+

High Altitude Platform+

Radar & Satellite Ground Base Station+

TV / Radio / WIFI / MAX / Mobile Base Stations

Fig.14. Multilayered Network Communication Solution Architecture

8. CONCLUSIONMultilayered Communication Network Solution consisting

of Communication Satellites, Mini / Micro / Nano Satellites and High Altitude Platforms will provide the communication network platform and its architecture for Bangladesh in future. The High Altitude Platform layer gives an advantage to wireless communications because HAPs are seen as a middle ground between the terrestrial and satellite cases and it offers reduced propagation delay and offer broadband covertures.

For indigenization this type technology can’t be master in a short period of time. We may need minimum 8 to 10 years to develop our own Multilayered Network. Now this is the time to decide how our country’s future Network Communication Platform and Space Application Program will go. Do us going to depends on other countries or we should go for our own program for what will our need of Communication Network and Space Based Applications after 20 years from now.

ACKNOWLEDGMENTWe thank Bangladesh Space Research and Remote Sensing

Organization (SPARRSO) and Bangladesh Aerial Photography Service (BAPS) for their recourse sharing and cooperation.

We also thank Indian Space Research Organisation (ISRO), National Aeronautics and Space Administration (NASA), Project CAPANINA and STRATXX for their information sharing.

REFERENCES[1] High Altitude Platforms in Wikipedia

http://en.wikipedia.org/wiki/High_Altitude_Platforms[2] High-Altitude Platforms for Wireless Communications by Alejandro

Arago´ n-Zavala, Jose´ Luis Cuevas-Ruı´z, Jose´ Antonio Delgado-Penı´n

[3] Y. C. Foo, W. L. Lim, and R. Tafazolli, "Centralized Downlink Call Admission Control for High Altitude Platform Station UMTS with Onboard Power Resource Sharing," in Vehicular Technology Conference,VTC 2002-Fall, 2002, pp. 549-553.

[4] T. Hult, A. Mohammed, and D. Grace, "WCDMA Uplink Interference Assessment from Multiple High Altitude Platform Configurations," EURASIP Journal on Wireless Communications and Networking, vol.2008, 2008.

[5] Bangladesh Aerial Photography Service (BAPS) Website: http://www.bapsbd.com

[6] Bangladesh Space Research and Remote Sensing Organization (SPARRSO) Website:http://www.sparrso.gov.bd

[7] The CAPANINA Project Website: http://www.capanina.org/introduction.php

[8] STRATXX Near Space Technology Website:http://www.stratxx.com

[9] STRATXX X Station Website:http://www.stratxx.com/products/x-station

[10] Indian Remote Sensing Satellites System (IRS) Website: http://isro.org/satellites/earthobservationsatellites.aspx

[11] Indian Space Research Organization in Wikipedia http://en.wikipedia.org/wiki/Indian_Space_Research_Organisation

[12] Helios Prototype Website: http://www.nasa.gov/centers/dryden/news/FactSheets/FS-068-DFRC.html