认知无线电中发射端多波束形成算法及接收端低旁瓣波束形成算法

在认知用户基站发射端，针对多用户产生多波束使每个波束的主瓣方向对准目标信号而零陷对准干扰方向，实现多用户同频通信从而提高频谱的利用率。而接收端需要波束形成算法具有抗干扰的能力，因此，本文提出了适用于授权用户基站接收端的低旁瓣波束形成算法，在主用户面对干扰时，其接收信号质量不会大幅下降。仿真实验验证了本文的算法。

Multi Beam Transmit Beamforming and Low Sidelobe Receive Beamforming Algorithm in Cognitive Radio

In CR networks, a transmitting and receiving beamforming algorithm is proposed. In transmitting beamforming, a multi beam algorithm is proposed to send different signals to different secondary users. In receiving beamforming, a low side lobe beamforming algorithm is presented. To avoid the interference when primary and secondary users share the same spectrum, the problem of transmitting beamforming is transformed into the one that can be solved by CVX toolbox. In receive beamforming, based on the method of array pattern optimization, a low side lobe level receiving beamforming algorithm is proposed in primary base station to suppress the white noise and unexpected interference. Extensive numerical results using simulated wireless channels in two dimensions are presented to verify the effectiveness of the algorithm.