空时分组码在频率选择性衰落信道中的性能

从空时分组码的实用性出发,在频率选择性衰落信道中对其性能进行了研究.采用SIMULINK仿真工具构造了频率选择性衰落信道的仿真模型.模型由信道、发射端和接收端组成:信道部分由多径Rayleigh信道和高斯白噪声构成;发射端由串并变换和空时分组编码器组成,并对信号进行扩频和加扰;接收端使用理想的RAKE接收机.仿真结果表明:在频率选择性衰落信道中,对于慢变化信道,随着信道路径数的增加,误比特率明显降低;对于快变化信道,随着信道路径数的增加,误比特率有所上升,而且信道路数越多,误比特率上升越明显.

Performance of Space-Time Block Code in Frequency-Selectivity Fading Channel

To discuss the STBC practicability,the STBC performance in a frequency-selectivity fading channel is studied.A simulation model in the channel is developed using SIMULINK,which comprises a channel,transmitting end and receiving end,where the channel comprises a multipath Rayleigh channel and Gaussian white noise; the transmitting end comprises a serial-parallel converter and space-time block coder with spectrum spread and signals disturbed;the receiving end uses an ideal RAKE receiver.The simulating results showed that when a channel varies slowly the BER(bit error rate) falls down obviously and while it varies quickly the BER rises up somewhat,and either the falling or rising occurs with the increasing number of channel paths.And the more the number of paths is,the clearer the BER rises up.