Title :
Performance of π/4 SQAM in a hard-limited channel in the presence of AWGN
Author :
Palmer, Craig S. ; Feher, Kamilo
Author_Institution :
Southwestern Bell Technol. Resources, St. Louis, MO, USA
fDate :
6/1/1993 12:00:00 AM
Abstract :
A strategy that reduces the spectral spreading when an ideal hard-limiter is used as a first approximation to a fully saturated power amplifier is presented. This strategy combines superposed quadrature amplitude modulation (SQAM) filtering with the π/4-shift quadrature phase-shift keying (QPSK) digital transmission format adopted for the first generation of US digital cellular systems. Simulation results showed that this π/4 SQAM filtering strategy increased capacity by 35% in comparison to hard-limited π/4 QPSK. Using computer-aided design, a receive filter that would limit the degradation of E b/N0 to less than 1.4 dB at a bit error rate of Pe=10-4 was selected
Keywords :
amplitude modulation; cellular radio; digital radio systems; phase shift keying; random noise; π/4 SQAM; π/4-shift quadrature phase-shift keying; AWGN; QPSK; US digital cellular systems; bit error rate; capacity; degradation; digital filtering; digital transmission format; fully saturated power amplifier; hard-limited channel; ideal hard-limiter; receive filter; spectral spreading; superposed quadrature amplitude modulation; Bit error rate; Computational modeling; Degradation; Design automation; Digital filters; Filtering; Phase shift keying; Power amplifiers; Quadrature amplitude modulation; Quadrature phase shift keying;
Journal_Title :
Broadcasting, IEEE Transactions on
