自适应OFDM算法及其在煤矿井下无线通信系统中的应用

由于频率选择性衰落,OFDM的每个子信道的频率响应各不相同,为了保证系统的误码率性能,OFDM只能根据衰减最大的子信道来决定比特和功率的分配,造成很大的浪费。因此,文章提出了一种自适应OFDM(AOFDM)算法,该算法使得OFDM的每个子载波都能根据信道特性动态的变化选择调制方式和功率分配,最好地匹配信道容量。文章详细介绍了AOFDM的比特、功率算法,并详细分析了煤矿井下无线通信系统的特点,指出AOFDM算法非常适用于煤矿井下无线通信系统,并给出了基于AOFDM的矿井无线通信系统的组成框图,仿真结果表明使用效果良好。

Adaptive OFDM Algorithm and Its Application in Underground Wireless Communication System

Because of selective fading of frequency,the frequency response of each subchannel of OFDM is different.In order to ensure bit error rate performance of the system,OFDM will decide distribution of bit and power according to the largest attenuation of the subchannels,which will cause great waste.So,the paper presented an adaptive OFDM(AOFDM) algorithm which made each carrier wave of OFDM to select modulation mode and power distribution according to dynamic change of channel charac-(teristics) and got the best match of channel capability.The paper introduced bit and power algorithm of AOFDM in details,analyzed characteristics of underground wireless communication system,and pointed out AOFDM algorithm was very suit for underground wireless communication system.It also gave block diagram of designed underground wireless communication system based on AOFDM.Simulation(result) showed that the system has good applying effect.