一种抑制相位噪声的多通道变时延下变频全双工收发方法

相位噪声会限制全双工(FD)收发机的自干扰抑制能力，恶化有用信号解调性能，即使全双工收发机采用发射机、接收机共用本振的结构，也无法消除相位噪声的限制作用。为了降低多径自干扰(SI)分量中相位噪声的影响，该文提出一种多通道变时延下变频全双工收发方法，具体包括可以补偿相位噪声的全双工收发机设计和能够抑制残余相位噪声的自干扰抑制算法。多通道变时延下变频全双工收发机采用多条通道接收同一天线的信号，各接收本振信号为经过不同延时调整的发射本振信号，可以在下变频时补偿多径自干扰中的相位噪声。自干扰抑制算法利用不同接收信号估计相位噪声参数，进一步降低残余相位噪声的影响。此外，该文推导了这种全双工收发方法的自干扰抑制能力，并给出了其随发射功率、接收通道数量的变化关系。分析与仿真结果表明，当接收通道数量高于自干扰信道强径数量时，多通道变时延下变频全双工接收方法不受相位噪声影响。

A Multiple-downconversion Full-Duplex Transceiver Receiver Design for Phase Noise Suppression

Phase noise limits the cancellation capability of a Full-Duplex (FD) transceiver receiver and degrades the demodulation performance of the signal-of-interest, even for the transceiver receiver which deploy one common oscillator for its transmitter and its receiver. In order to mitigate the phase noises contained in the multipath Self-Interference (SI) components, a multiple-downconversion FD transceiver receiver design is proposed to suppress these phase noises. The proposed multiple-downconversion FD transceiver receiver design includes a new FD transceiver architecture with multiple receive chains, and a phase noise cancellation algorithm. The FD transceiver architecture deploys multiple receive chains to downconvert the signal received by one antenna. Particularly, the oscillator signal of each receive chain is originated from the transmit oscillator with a unique delay, such that the phase noises contained in the multipath SI components can be compensated. The phase noise cancellation algorithm deploys the received signals in different receive chains to estimate the phase noise coefficients, which can cancel the residual phase noise after the multiple-downconversion. The cancellation capability of the cancellation algorithm is derived and analyzed. Analytical and simulation results demonstrate that, in the scenario that the number of receive chains is greater than the number of strong multiple SI components, the phase noise does not affect the cancellation capability of proposed FD transceiver.