Studies Of Spatial Isolation Technology In Phased Arrays

Simultaneous Transmit and Receive technology can transmit and receive phased array signals at the same time,thus effectively improving the efficiency of spectrum utilization,but when the signals are transmitted and received at the same time,strongself-interference signals are generated.Based on phased array system full-duplex application,especially Aperture-Level Simultaneous Transmit and Receive phased array,the suppression of self-interference signal is of great significance.According to the existing research,the full-duplex system completes the selfinterference cancellation in various techniques,such as spatial domain methods,propagation domain methods,etc.This paper aims to explore the spatial isolation technology of phased array,which mainly includes the following aspects:Firstly,this paper introduces the subject's background,significance and research status.At the same time,the key of simultaneous transmit and receive technology,including spatial domain,RF domain and digital domain,are analyzed.Secondly,in order to the realization of simultaneous transmit and receive,an optimizing support combining genetic algorithm with transmitting beam forming is proposed.According to the coupling characteristic matrix,the array model is established.Then,according to the features of the phased array system such as the radiation gain and the self-interference suppression's requirement,this part constructs an optimized objective function model.In the meanwhile,genetic algorithm(GA)is used to get the optimal value.And the isolation of subarray can be improved by optimizing the amplitude and phase of the transmitting signal.Finally,this part set up an experiment platform to verify the optimal value.Reference to the conventional array,the features of the transmitting beam and the selfinterference are tested and analyzed,includes amplitude-phase optimization and allphase optimization,which turns out the availability of spatial interference suppression method.The results show that the isolation of 14.4dB and 11.9 dB at 10GHz can be obtained by amplitude-phase optimization and all-phase optimization,at the same time,the gain loss 2.53 dB and 2.81 dB.