Abstract:

In order to solve the contradiction between the increasing aerospace measurement and control services and the shortage of spectrum resources for aerospace measurement and control links,an implementation architecture for co-time co-frequency full-duplex measurement and control links is proposed,designed,and experimentally verified.The links adopt a multi-domain self-interference cancellation mechanism that combines the spatial domain,radio frequency domain and digital domain,which improves the spectral efficiency under the condition that the ranging accuracy should not be reduced.For spatial self-interference cancellation,an integrated parabolic antenna with high isolation in a common surface feed is designed,and structured choke measures are adopted between the transceiver elements.The coupling effect between the transmitting and receiving elements is reduced.The isolation of the antenna system is improved.The self-interference cancellation in the radio frequency domain adopts the multi-tap self-interference cancellation method.A multi-tap reconstruction radio frequency signal model is established,and the minimum norm solution of the multi-tap coefficients is given aiming at minimizing residual interference power.In the digital domain,a nonlinear self-interference signal model is established and the least squares estimation is adopted to obtain nonlinear coefficients.In addition,this paper verifies the feasibility and effectiveness of the multi-domain self-interference cancellation architecture of the full-duplex measurement and control system through simulation and experiments.The results show that the total self-interference suppression reaches 156.5 dB with accurate distance measurement.

Key words: aerospace measurement and control, co-frequency and co-time full duplex, self-interference cancellation, experimental verification