摘要
本文介绍了一种模拟移动无线电接收中遇到的瑞利分布衰落的设备。该设备由软件和硬件组成,用两个独立的高斯噪声信号对无线电信号进行同相和正交调制,相加后得到瑞利衰落信号。接收信号理论上的功率谱用FIR数字滤波器对伪噪声的功率谱进行整形来近似。噪声的产生和滤波均由单板机实现。改变单板机CTC定时器的输入时间常数,就可直接调整模拟衰落信号的衰落速率。对设备的测试结果表明:模拟的衰落信号的包络统计与理论统计特性和实验观察基本一致。
A real-time Rayleigh fading simulator to simulate the Rayleigh-distributed fading encountered in mobile radio is described. The fading statistics is achieved by in-phase and quadrature modulation at the radio signal by two independent Gaussian noise signals. The theoretical spectrum of the received signal is approximated by shaping the spectrum of the source noise with FIR filters. The noise generation and filters are performed by a microprocessor for which the input time constant of CTC can be varied to control the fading rate. Envelope fading distributions statistics produced by this device show close agreement with theoretical statistics and documented experimental data.
出处
《通信学报》
EI
CSCD
北大核心
1991年第1期37-42,共6页
Journal on Communications
