Title :
Phase errors in the coherent demodulation of VPSK and a solution using DSSS modulation
Author :
Whaits, Clive V. ; Braun, Robin M.
Author_Institution :
Dept. of Electr. Eng., Cape Town Univ., Rondebosch, South Africa
Abstract :
The use of single sideband suppressed carrier (SSBSC) techniques in conjunction with digital modulation schemes, like variable phase shift keying (VPSK) places stringent phase requirements on coherent demodulation. In this paper, the problems of coherent demodulation and soft decision detection/decoding in a conventional 2-VPSK modulation scheme, with a bandwidth efficiency of 4 bits per Hertz, are discussed and then a possible solution using direct sequence spread spectrum (DSSS) modulation is presented
Keywords :
decoding; digital communication; phase shift keying; signal detection; spread spectrum communication; 2-VPSK modulation scheme; DSSS modulation; VPSK; bandwidth efficiency; coherent demodulation; digital modulation schemes; direct sequence spread spectrum modulation; phase errors; phase requirements; single sideband suppressed carrier techniques; soft decision detection/decoding; variable phase shift keying; Binary phase shift keying; Bit rate; Cities and towns; Clocks; Decoding; Demodulation; Digital modulation; Optical signal processing; Phase modulation; Spread spectrum communication;
Conference_Titel :
Communications and Signal Processing, 1997. COMSIG '97., Proceedings of the 1997 South African Symposium on
Conference_Location :
Grahamstown
Print_ISBN :
0-7803-4173-2
DOI :
10.1109/COMSIG.1997.629991
