一种MIMO中继系统的自适应自干扰消除方法

为节省频率资源，全双工中继一般采用相同的频率接收和发射信号。由于收发天线之间无法充分隔离，接收天线容易受到自身发射天线的回波干扰。针对宽带全双工多输入多输出( MIMO)中继的自干扰问题，提出了一种基于梯度下降自适应算法的自干扰消除方法。该方法利用中继反馈的已知信号进行自干扰信道估计，并产生一个对自干扰信号的估计信号，从而在接收端将干扰抑制。仿真结果表明，该方法在自适应滤波器的跟踪性能、收敛分布和不同 MIMO 配置下的均方误差( MSE)性能等方面均取得良好效果。

An adaptive self-interference cancellation method in MIMO relay systems

Full-duplex relays simultaneously receive and transmit at the same frequency for saving frequency resource,thus the undesired feedback from the transmitting antennas to receiving antennas is created by the radio echoes at the same time for the lack of isolation between antennas. Based on an adaptive steepest descent algorithm,the self-interference cancellation scheme is presented to solve the problem of self-interference for the full-duplex broadband multiple-input multiple-output(MIMO) relays. The characteristics of self-interference echo channel are estimated by the feedback signals from the output of relay,and then an estimated signal is generated to suppress self-interference echo to a tolerable level. The simulation results show that the scheme is obviously effective on the filter tracking performance,convergence distribution and mean squared error(MSE) for different MIMO configurations.