基于射频耦合与数字重建的同址干扰对消

Co-site interference cancellation based on RF coupling and digital reconstruction

提出了一种改进的联合射频耦合与数字重建的射频域对消方法.射频耦合对消阶段根据最小化加权信道响应原则优化抽头系数,将干扰强度更高的线性成分赋予较大权重,等效减小了多抽头对消带宽,从而增大该阶段干扰对消比.数字重建射频对消阶段对发射机功放、干扰信道和多抽头射频对消结构联合建立非线性模型,采用最小二乘法提取模型参数,在数字域重构干扰信号并利用射频链路发送到射频域以对消剩余干扰.仿真结果表明:该方法在降低硬件复杂度的同时仍能获得高对消比.

An improved interference cancelling method in radio frequency (RF) domain was proposed,which combined RF coupling and digital reconstruction.In RF coupling cancellation phase,tap coefficients were optimized under the criteria of minimizing the weighted channel response by giving the strong linear interference component bigger weight,which equivalently reduced the cancelling bandwidth of the multi-tap structure,resulting in improved cancellation performance of this phase.In digital reconstruction phase,a joint nonlinear model was built,in which the transmitter power amplifier and the interference channel together with the RF multi-tap cancellation structure were comprised.The least square (LS) algorithm was implemented to extract the model parameter, and then the interference signal was reconstructed in digital domain and subsequently transmitted to RF domain to cancel the residual interference utilizing an extra RF chain.Simulation results show that the proposed method can reduce hardware complexity while still obtaining high interference cancellation ratio.