Abstract - A packet reservation multiple access (PRMA) assisted microceflutar cordless telecommunications (CT) system is investigated for office type environments in absence of cochannel interference. The objective speech quality is found as a function of channel signal-to-noise ratio (SNR) for transmissions over narrowband Rayleigh fading channels, parameterized with the number of PRMA users. A moderate complexity 16-ary CT scheme constituted by a 4-bit/symbol 32-kbps adaptive differential pulse code modulation (ADPCM) speech codec, Reed-Solomon forward error correction (FEC) codec, and diversity-assisted 16-level star quadrature amplitude modulation (16-StQAM) modem is proposed. The 264-kBd 20-slot PRMA scheme supports 36 users while maintaining virtually imperceptible speech degradation for channel SNR's in excess of about 25 dB, and for a mobile speed of 2 mi/h if the signal-to-interference ratio (SIR) is above 30 dB.
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机译:摘要-在没有同频道干扰的情况下,针对办公室类型的环境,研究了分组保留多路访问(PRMA)辅助的微头颅无绳电信(CT)系统。发现客观语音质量是通过PRMA用户数量进行参数化的窄带瑞利衰落信道上传输的信道信噪比(SNR)的函数。由4位/符号32-kbps自适应差分脉冲编码调制(ADPCM)语音编解码器,里德-所罗门前向纠错(FEC)编解码器和分集辅助16级星型正交编码构成的中等复杂度16进制CT方案提出了调幅(16-StQAM)调制解调器。 264 kBd 20时隙PRMA方案支持36个用户,同时对于超过约25 dB的信道SNR以及2 mi / h的移动速度(如果信噪比(SIR)为),保持几乎察觉不到的语音质量下降30 dB以上。
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