水声通信自适应多普勒频移补偿仿真研究

在水声通信中,当收发双方存在一定加速度时,传统的多普勒频移补偿误差较大,影响码元同步并降低接收性能.为了补偿加速度下的多普勒频移,提出一种自适应多普勒频移补偿方法,在均衡的同时利用最大似然函数计算插值因子并对信号进行线性插值,以补偿加速度引起的每帧数据内不断变化多普勒频移.通过计算机仿真,验证了该方法的有效性,并将其与传统方法进行了性能对比.由于不需要加入专用的数据用来检测多普勒频移,所以还可以提高一定的频带利用率或功率利用率.

Adaptive Doppler Compensation for Underwater Acoustic Communication

In underwater acoustic communication, because of the high residual frequency error, traditional Doppler compensation is not efficient for symbol synchronization when there is acceleration between transmitter and receiver, which result in low receiving performance. In this paper a Doppler compensation method under acceleration is studied. To compensate the variable Doppler shift during a frame of data, interpolating factor is calculated through maximum likelihood function and interpolation is done at the same time with equalization. The simulation results show that, compared with traditional method, this algorithm is effective at high moving speed and moderate acceleration. And as no extra data is needed to calculate the frequency shift, bandwidth efficiency or power efficiency can be improved.