Proceedings of the Second International Mobile Satellite Conference (IMSC 1990)

Presented here are the proceedings of the Second International Mobile Satellite Conference (IMSC), held June 17-20, 1990 in Ottawa, Canada. Topics covered include future mobile satellite communications concepts, aeronautical applications, modulation and coding, propagation and experimental systems, mobile terminal equipment, network architecture and control, regulatory and policy considerations, vehicle antennas, and speech compression

Proceedings of the Fifth International Mobile Satellite Conference 1997

Satellite-based mobile communications systems provide voice and data communications to users over a vast geographic area. The users may communicate via mobile or hand-held terminals, which may also provide access to terrestrial communications services. While previous International Mobile Satellite Conferences have concentrated on technical advances and the increasing worldwide commercial activities, this conference focuses on the next generation of mobile satellite services. The approximately 80 papers included here cover sessions in the following areas: networking and protocols; code division multiple access technologies; demand, economics and technology issues; current and planned systems; propagation; terminal technology; modulation and coding advances; spacecraft technology; advanced systems; and applications and experiments

On QAM Speech Transmission Schemes for Microcellular Mobile - PCNs

On the way towards third generation personal communication networks (PCN) the deployment of 16-level quadrature amplitude modulation (QAW schemes is investigated via flat microcellular Rayleigh-fading mobile radio channels having mild co-channel interference with and without diversity. Our proposed differentially coded non-coherent 16-QAM scheme requires no pilot symbol assistance, no automatic gain control (AGC) and no carrier recovery. High speech quality associated with a mean opinion score of about four (MOS = 4.0) is ensured at a signalling rate of 6.1 kBd for channel signal to noise ratios tSNR) above 30 - 25 dB and signal to interference ratios (SIR) above 75 - 30 dB by the 13.4 kbit/s medium complexity regular pulse excited (RPE) speech codec, when carefully matched twin-class low complexity binary Bose-Chaudhuri-Hocquenghem (BCHI error correction coding and 16-QAM combined with second order diversity are deployed. The overall speech delay is about 10 Ins and the user bandwidth is 9.3 kHz. which allows us to accommodate 2 1 users in a 300 kHz channel slot

Proceedings of the Third International Mobile Satellite Conference (IMSC 1993)

Satellite-based mobile communications systems provide voice and data communications to users over a vast geographic area. The users may communicate via mobile or hand-held terminals, which may also provide access to terrestrial cellular communications services. While the first and second International Mobile Satellite Conferences (IMSC) mostly concentrated on technical advances, this Third IMSC also focuses on the increasing worldwide commercial activities in Mobile Satellite Services. Because of the large service areas provided by such systems, it is important to consider political and regulatory issues in addition to technical and user requirements issues. Topics covered include: the direct broadcast of audio programming from satellites; spacecraft technology; regulatory and policy considerations; advanced system concepts and analysis; propagation; and user requirements and applications