论文信息 - Variable rate QAM for mobile radio

Variable rate QAM for mobile radio

Quadrature amplitude modulation (QAM) schemes which vary the number of modulation levels in accordance with the mobile radio fading channel variations are investigated. Important parameters considered are the fading rate and the block size used. We describe how the adaptive QAM modems can be employed and consider their use in a DECT-like TDD packet structure. System performance in the presence of cochannel interference is also considered. Simulations show that the variable rate system has about 5 dB improvement in channel SNR over a fixed 16-level QAM system for BER's between 10/sup -2/ and 10/sup -5/ and channel SNR's between 25 and 40 dB. >

W. T. Webb | R. Steele | R. Steele | W. Webb

[1] R. Steele,et al. Transmission of log-PCM via QAM over Gaussian and Rayleigh fading channels , 1987 .

[2] W.T. Webb. Modulation methods for PCNs , 1992, IEEE Communications Magazine.

[3] R. Steele,et al. Logarithmic PCM weighted QAM transmission over Gaussian and Rayleigh fading channels , 1987 .

[4] William Webb,et al. Bandwidth efficient QAM schemes for Rayleigh fading channels , 1990 .

[5] John G. Proakis,et al. Digital Communications , 1983 .

[6] Raymond Steele,et al. A subband coding, BCH coding, and 16-QAM system for mobile radio speech communications , 1990 .

[7] R. Steele,et al. Technologies on the horizon-deploying personal communication networks , 1990, IEEE Communications Magazine.