用实验法对450MHz最小可用接收电平质量的分析

摘要

When radio signal propagates in space,distortions may occur in amplitude,frequency and phase due to multi-path reflections and Doppler Effect.By testing the distorted signal of 450 MHz minimum useable receiving level through simulation,the authros conclude that the audio frequency output SINAD of locomotive radio is higher than 20 dB and comply with the provision of TB/T 3052—2002 when ignoring the influence of noise and frequency error.%无线信号在空间传播过程中,由于会发生多径反射和受到多普勒效应的影响,其振幅、频率和相位都会发生失真。通过对模拟出失真的450MHz最小可用接收电平的测试表明,在不考虑噪声影响和频率容差时,机车台音频输出信纳比大于20dB,符合TB/T3052—2002《列车无线调度通信系统制式及主要技术条件》的规定。