Wide Frequency Coverage Broadband Self-interference RF Suppression Circuit Design And Verification

In today's information explosion,the limited spectrum resources contradict the growing communication demand.The important way to solve this contradiction is to improve the utilization of spectrum resources.Therefore,the research on higher frequency and larger signal bandwidth is also increasing.Higher frequency and larger signal bandwidth also mean more self-interference signals,which will affect the demodulation of useful signals by the receiver.Therefore,how to suppress the selfinterference signal has become an urgent problem to be solved.Based on the selfinterference RF Suppression Technology,the wide frequency coverage broadband selfinterference RF suppression circuit is designed and verified.Firstly,thesis introduces the research status and research results of broadband selfinterference suppression technology.According to the application scenarios and index requirements of wide frequency coverage broadband self-interference RF suppression circuit,the design scheme of the circuit is given.In the multipath environment,the effects of the number of reconstruction branches,transmission delay accuracy,phase accuracy,amplitude accuracy and other parameters on the self-interference RF suppression performance are analyzed.The analysis shows that the more the number of reconstruction branches,the higher the transmission delay accuracy,the higher the phase accuracy and the amplitude accuracy,the better the self-interference RF suppression performance.Then the self-interference RF Suppression Effect of signals with different bandwidth is verified by simulation.The simulation results show that under the condition of reconstructing four branch signals,the self-interference RF Suppression Performance of 50 MHz broadband signal in the frequency range of 6GHz ? 18 GHz can reach more than 30 d B;500MHz broadband signal,self-interference RF Suppression Performance of more than 15 d B.Secondly,thesis completes the hardware implementation of broadband selfinterference RF suppression circuit with wide frequency coverage.According to the design scheme,the overall structure design and link budget of self-interference RF suppression circuit are given.The whole structure is divided into several modules,and the device selection of each module is completed.Finally,the wide-frequency coverage broadband self-interference RF suppression circuit is realized.Finally,thesis completes the debugging of wide frequency coverage broadband selfinterference RF suppression circuit.Firstly,the performance indexes of each module are tested,and then the self-interference RF Suppression Performance of the circuit board is tested.The test results show that in the frequency range of 6GHz ? 18 GHz,the selfinterference RF Suppression Performance of 50 MHz broadband signal reaches 32 d B;500MHz broadband signal,self-interference RF suppression performance reaches 16 d B.To sum up,thesis designs and implements a broadband self-interference RF suppression circuit with wide frequency coverage.The working frequency range is 6GHz? 18 GHz,and the maximum signal bandwidth is 500 MHz,which can suppress a certain strong self-interference signal.It provides some theoretical and hardware support for selfinterference RF Suppression Technology with higher frequency and larger signal bandwidth in the future.