论文部分内容阅读
从现有模拟通信过渡到数字通信,视距微波的数字化以传送四次群或两个三次群为宜。但由于视距微波多径传输效应,形成频率选择性衰落;因此在高码率传输中,必须采用适当的方法来克服多径衰落引起的码间干扰。本文对140Mbit/s和34Mbit/s的4PSK和8PSK数字微波系统进行了计算机模拟。模拟计算证明采用自适应判决反馈均衡器(DFE)或VA判决均衡器(简称VA判决)均能大大减少码间干扰,使误码率得到明显改善;在一般深衰落下使通信不致中断。
From existing analog communications to digital communications, line-of-sight digitization of microwaves is preferable for transmitting quadruplets or two triplets. However, due to the effect of line-of-sight microwave multipath transmission, the frequency selective fading is formed. Therefore, in the case of high bit rate transmission, an appropriate method must be adopted to overcome intersymbol interference caused by multipath fading. In this paper, 140Mbit / s and 34Mbit / s 4PSK and 8PSK digital microwave systems were computerized. Simulation results show that using adaptive decision feedback equalizer (DFE) or VA decision equalizer (referred to as VA decision) can greatly reduce intersymbol interference, resulting in a significant improvement in bit error rate; under normal deep fading, the communication will not be interrupted.