Title :
Superposed transmission of high speed QPSK signals and SSMA-QPSK signals in non-linear channels
Author :
Morikura, Masahiro ; Sugiyama, Takatoshi ; Kazama, Hiroshi ; Kubota, Shuji ; Kato, Shuzo
Author_Institution :
NTT Radio Commun. Syst. Lab., Kanagawa, Japan
Abstract :
Spread-spectrum multiaccess quadrature phase-shift keying (SSMA-QPSK) signal transmission superposed over high-speed QPSK modulated signals is proposed and analyzed experimentally. Experimental results show that when the SSMA-QPSK signal power to QPSK signal power ratio equals -30 dB, the scheme can transmit 20 SSMA-QPSK channels and a high-speed QPSK channel over the same transponder simultaneously and realize 1.530 b/s/Hz of frequency utilization efficiency (superposed transmission of 60-Mb/s QPSK signals and 20 32-kb/s SSMA-QPSK signals over a 36-MHz transponder)
Keywords :
error correction codes; multi-access systems; phase shift keying; satellite relay systems; spread spectrum communication; visual communication; 32 kbit/s; 60 Mbit/s; SSMA-QPSK signals; cochannel interference; frequency utilization efficiency; high speed QPSK signals; high-coding-gain forward error correction; nonlinear channels; satellite communications; superposed transmission; video signals; Business communication; Forward error correction; Frequency modulation; Mobile communication; Quadrature phase shift keying; Satellite broadcasting; Satellite communication; Satellite ground stations; Transponders; Videoconference;
Conference_Titel :
Global Telecommunications Conference, 1992. Conference Record., GLOBECOM '92. Communication for Global Users., IEEE
Conference_Location :
Orlando, FL
Print_ISBN :
0-7803-0608-2
DOI :
10.1109/GLOCOM.1992.276422
