World Administrative Radio Conference Research Articles

Cross-Curtain Radio Cooperation and New International Alignments during the Cold War

The transformation of the international system in the 1970s had remarkable consequences for East-West relations in the field of international radio communications. The two opposing blocs were compelled to join forces in an international system that was in a state of flux. Third World countries had started putting forward their demands for a “New International Information Order” and increasingly exerted pressure to achieve a reallocation of the spectrum for their own benefit. However, they were not able to reach their objectives at the World Administrative Radio Conference convened in 1979 by the International Telecommunication Union in order to reallocate the entire radio frequency spectrum. Expert groups from East and West cooperated closely on this issue, developing a coordinated strategy that enabled them to defend their shared interests.

Application of a new Terrestrial Telecommunications System in the European Air Traffic

Aeronautical Public Correspondence (APC) is a telecommtmicationsse!Vice, which enables passengers onboard aircraftto make telecommunication calls to people on the ground.This article describes the terrestrial communications seiVicewhich is based on cellular network for the European CEPTmember countries (CEPT- European Conference of Postaland Telecommunications Administrations) named TerrestrialFlight Telecommunications System (TFTS).This system is a Pan-European System, which means theusage of hannonised frequencies in Europe with hannonisedstandards for the TFTS equipment, which have been issued bythe European Telecommunications Standard Institute (ETSI).Frequencies allocated for TFTS have been designated bythe World Administrative Radio Conference, WARC-92 withfrequency bandwidth of 2x5 MHz:1670- 1675 MHz, for ground to air1800- 1805 MHz, for air to ground.TFTS planning is perfonned by the application of frequencyblocks (42 blocks) with 164 channels in total. Bandwidthof each radio channel, which contains 4 speech channels,is equal to 30.3 kHz.Due to the very high flight of the aircraft (about 13,000 m),it needs a long distance between the centres of cells (radio stationon the ground) to avoid the eo-channel or adjacent channelinteJference.The article presents the planning process with typical cellradius of240km or 350km. In the viewofthatfact, the need ispointed out for finding a compromise solution with regard toemitting power and the influence of interference.Final(v, it is noted that TFTS ground radio stations inCroatia, which are located in Zagreb and Split, may cover theterritory of some neighbouring countries other than Croatia,which is important from the commercial point of view.

2.6 GHz band satellite ISDB system for mobile reception

At the World Administrative Radio Conference (WARC)-92, the 2.6 GHz frequency band was allocated to a group of East Asian countries including Japan. This band is being studied for use in mobile multimedia broadcasting. This paper describes the outline of a system for 2.6 GHz band mobile multimedia broadcasting services, together with its requirements. In particular, the effects of the broadcasting signals attenuation due to shadowing by buildings and foliage, and the signals deterioration due to multipath propagation and fading, must be taken into account in order to realize the 2.6 GHz band system. This study considers the economic and technical constraints related to the modulation schemes, transmitting power, satellite antenna reflector aperture, the gain of the receiving antennas and the scale of the satellites. The configuration of satellite hardware systems based on the channel plan, channel bandwidth, and other specifications is investigated taking into account of these constraints. For example, a bit-rate of 4.8 Mbps can be provided when a 2-ton class satellite bus is utilized. This indicates that 2.6 GHz band services are technically feasible.

Spectrum sharing considerations for the proposed ESA ‘archimedes’ satellite DAB service

AbstractAt the 1992 World Administrative Radio Conference (WARC), spectrum was allocated, on a primary basis, to the broadcast satellite service (sound). The allocations were not, however, uniform worldwide, nor will the BSS(S) have sole use of these allocations. In addition, many countries have reserved primary use of the spectrum for existing services until 2007, with the BSS(S) permitted only on a noninterference basis.This situation will impose serious constraints on the proposed ESA S‐DAB service, to be radiated from the ‘Archimedes’ constellation of satellites. The launch date for this service may be before the end of the century, and sharing with other spectrum users will therefore be necessary. Such users include fixed telephony links, broadcast links and mobile aeronautical telemetry.This paper reviews current spectrum usage in Europe and elsewhere, and investigates the restrictions thus imposed on the ESA S‐DAB service. Numerical examples based on real‐world systems are given, and demonstrate the feasibility, in many cases, of spectrum sharing.

Characteristics of fading of HF signal and noise intensities on three paths between the United Kingdom and Turkey

Results from a recent measurement campaign in Turkey, pertinent to reliability and compatibility determination in HF service planning, are presented. Within‐an‐hour signal fading was found to be slightly more severe than, but day‐to‐day variability only half as large as the values (in decibels) adopted by the 1984 World Administrative Radio Conference on HF Broadcasting, or WARC‐HFBC(84). Within‐an‐hour variability of noise was negligible, and day‐to‐day variations of noise were only about one quarter of the amplitude (in decibels) given by CCIR report 322‐3 [International Radio Consultative Committee (CCIR), 1988a]. The day‐to‐day spatial correlation coefficients of both signal and noise at sites separated in range by about 400 km were found to be about 0.4. Correlation of signal with noise at each site was negligible.

Future public land mobile telecommunication systems.

In March 1992, the World Administrative Radio Conference (WARC) of the International Telecommunication Union (ITU), identified global bands 1885-2025 and 2110-2200 MHz for future public land mobile telecommunication systems (FPLMTSs), including 1980-2010 and 2170-2200 MHz for the mobile satellite component. The potential for all FPLMTS radio interfaces to be in the same band provides a strong incentive for trying to maximize the commonality between the satellite and terrestrial component of FPLMTSs. This would simplify multimode mobile equipment and also greatly increase the utility of FPLMTSs for the provision of basic telecommunication needs in underdeveloped regions of the world. Extension of integrated voice, video and data telecommunications to a person rather than a place will have a dramatic effect on everyday life, and on the organizations which currently provide these services. The author outlines some of the international standards work in this area being carried out by the International Radio Consultative Committee/International Telegraph and Telephone Consultative Committee (CCIR/CCITT), in particular that of CCIR TG8/1 (formerly IWP8/13) on FPLMTS.

Architecture and networking issues in satellite systems for personal communications

AbstractThe paper expands on some specific aspects of personal communications via satellite, often–although not necessarily–envisaging extensive use of ‘small’ satellites, using orbits not necessarily coinciding with the geostationary one (36,000 km), but rather at 1000–11,000 km altitude. One key point to be borne in mind is the issue of internetworking between satellite and terrestrial systems. Network integration should be carefully implemented in order to comply with ITU future public land mobile telecommunication systems (FPLMTS) requirements, also accepted in the European Telecommunication Standards Institute (ETSI) universal mobile telecommunication systems (UMTS). In addition to some insight into the technology of small satellites and associated orbits, architectures and networking aspects of most relevant systems providing personal communication services (PCS) are addressed in some detail, and potential applications highlighted. Frequency spectrum allocation is addressed in the light of the 1992 World Administrative Radio Conference (WARC‐92), taking into account also multiple access problems and regulatory issues such as Federal Communications Commission (FCC) licensing and spectrum sharing debates. Some remarks on critical technologies and cost conclude the paper.

The 1992 world administrative radio conference: A survey of the US delegation and recommendations for the future

The 1992 World Administrative Radio Conference discussed crucial issues regarding international spectrum allocation. In spite of the importance of the proceedings, little attention was paid to the conference by news media or trade press. This paper focuses on a survey of the 53 members of the US delegation to WARC-92. While most thought the delegation was effective in achieving most of its goals, they provided a number of recommendations to improve the efficiency of future US WARC delegations. The principal recommendation was that future delegations be selected earlier, especially the delegation leadership. In addition, the USA must be more active in seeking coalitions with other nations long before the conference itself actually begins. Many of the survey respondents mentioned the success of the European Community in the deliberations, primarily because 34 member nations supported any European-proposed initiatives.

Technology 1993-telecommunications

Significant events during 1992 are highlighted. Communication technologies began merging, with cable TV offering telephone service and telecommunication companies offering TV. Wireless personal communication systems (PCSs) got the green light when the 1992 World Administrative Radio Conference designed frequency bands for future mobile communications services, with provisions for such services to be handled via low-Earth-orbiting satellites, and the US Federal Communication Commission allocated frequencies in the 2 GHz band to the deployment of several emerging technologies, including PCSs. Multimedia communication took off with the introduction of new services. In optical communication, erbium-doped fiber amplifiers were installed in the world's longest repeaterless undersea link. Strained-layer multi-quantum-well lasers received increasing attention, due to the improved system and device properties they offer. Research on cheap optical interconnects and packages gained momentum. >

Future public land mobile telecommunication systems

In March 1992, the World Administrative Radio Conference (WARC) of the International Telecommunication Union (ITU), identified global bands 1885-2025 and 2110-2200 MHz for future public land mobile telecommunication systems (FPLMTSs), including 1980-2010 and 2170-2200 MHz for the mobile satellite component. The potential for all FPLMTS radio interfaces to be in the same band provides a strong incentive for trying to maximize the commonality between the satellite and terrestrial component of FPLMTSs. This would simplify multimode mobile equipment and also greatly increase the utility of FPLMTSs for the provision of basic telecommunication needs in underdeveloped regions of the world. Extension of integrated voice, video and data telecommunications to a person rather than a place will have a dramatic effect on everyday life, and on the organizations which currently provide these services. The author outlines some of the international standards work in this area being carried out by the International Radio Consultative Committee/International Telegraph and Telephone Consultative Committee (CCIR/CCITT), in particular that of CCIR TG8/1 (formerly IWP8/13) on FPLMTS.

How WARC '92 will affect mobile services

The US proposals to, and the decisions of, the 1992 World Administrative Radio Conference (WARC '92) that relate to mobile and mobile-satellite services are described. Mobile-satellite service (MSS) issues addressed at WARC '92 include new allocations for low Earth-orbit (LEO) satellite operations, new MSS spectrum allocations, and modifications to current allocations used to support mobile-satellite operations. Allocation issues on the agenda of WARC '92 that related to the terrestrial mobile services include allocations for mobile services between 1 and 3 GHz, allocations for aeronautical public correspondence, and designation of frequency bands for future public land mobile telecommunications services. A number of proposals which were put forward by the US to support MSS allocations and operations that did not explicitly require allocations to the MSS are discussed. >

WARC embraces PCN

A compromise reached at the 1992 World Administrative Radio Conference (WARC-92) concerning the international frequency allocations for personal communications systems (PCSs) is reviewed. The PCS debate at the WARC-92 resulted in the collision of two nearly polar views: that of the Europeans, whose advocacy of PCS techniques was limitless; and that of the United States, whose enthusiasm was considerably more restrained. The effects the compromise will have on PCS regulations in Europe and the United States are discussed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Global development of PCS

A brief survey of international efforts to address spectrum and incumbency issues and implement new personal communications services (PCS) is presented. Worldwide frequency allocations agreed to in the 1992 World Administrative Radio Conference (WARC 92) are discussed. The development of personal communication services in European, Asian, and North American countries is reviewed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Summary of conclusions of the 1992 World Administrative Radio Conference

The major decisions made at the conference are briefly described. Additional frequency bands for shortwave (HF) radio broadcasting were agreed upon. Frequency allocations were made to support a number of US proposals, to provide advanced mobile radio services using low Earth orbit satellites. Allocations for land based mobile services adopted at WARC '92, in the range 1700 to 2600 MHz, are meant to foster improved mobile services that can be used worldwide. An allocation was also made to support commercial telephone service between passengers flying on aircraft and individuals on the ground. Allocations were made for sound broadcasting from satellites, as well as for providing a means to accommodate a complementary terrestrial-based digital audio broadcasting service. New frequency allocations to support space activities were agreed upon, and an allocation was made to the fixed satellite service in the band 13.75 to 14.0 GHz. >

SETI and the radiospectrum

The distribution of radio bands to various users is a very difficult task internationally. Any signal emitted from outside the Earth will be badly deteriorated by any emission by man—several WARC (World Administrative Radio Conferences), set by ITU (International Telecommunication Union, an agency of the United States), attempt to minimize this effect.

Space communications

Six proposals for enhancing or expanding the electromagnetic spectrum allocated for communications supporting research in space, which will be heard by the 1992 World Administrative Radio Conference, are discussed. They will cover extravehicular activities, space operations, data relay links, deep space interplanetary probes, future planetary missions, and Earth exploration satellites. Of primary importance to most space agencies is the need to improve the status of the allocation of the space research, space operations, and Earth exploration satellite services in the bands 2.025-2.110 GHz and 2.20-2.29 GHz.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Broadcasting

Three major allocation issues involving the broadcasting and broadcasting-satellite services that will be discussed at the 1992 World Administrative Radio Conference (WARC-92) are examined. They are expansion of frequencies for conventional high-frequency (shortwave) broadcasting, new frequencies for both satellite and terrestrial digital audio (radio) broadcasting to handheld and automobile receivers, and new frequencies for studio-quality high-definition television broadcasting from satellites. The bands that are viable candidates for these services are discussed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Mobile communications

An important issue facing the 1992 World Administrative Radio Conference, namely, determining how to provide additional spectrum for both existing and entirely new mobile services, is examined. At least six types of mobile systems will be seeking new or expanded allocations; three involve satellites and three rely on primarily terrestrial techniques. All but one will be forced to compete for allocations in the same crowded 1-3 GHz frequency range. The various allocation proposals are discussed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

WARC's last act?

The upcoming 1992 World Administrative Radio Conference is discussed. The reasons for its importance are given, and three new types of services that are high on the list for consideration are examined. They are universal personal telecommunications, digital audio broadcasting, and high-definition satellite TV. US preparations for the conference and important international alliances are discussed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Mobile radio: An overview

Following a brief prologue and historical overview, such technical issues as the repertoire of systems and services, management of the airwaves, the operating environment, service quality, network issues and cell size, channel coding and modulation, speech coding, diversity, multiplex, and multiple access (FDMA, TDMA, CDMA) are discussed. Also addressed are the potential economic and sociological impacts of mobile radio communications in the wake of the redistribution of airwaves at the World Administrative Radio Conference WARC '92. Performance dependence on multipath delay (related to the cell size and terrain configuration), Doppler frequency (related to the carrier frequency, data rate. and the speed of vehicles), and message length (may dictate the choice of multiple access) is briefly discussed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>