An Adaptive Four-Port Cancellation Network Structure and Adaptive Cancellation Method

Abstract

The invention discloses a self-adaptation four-port cancellation network structure and a self-adaptation cancellation method. The structure comprises an amplitude-phase cancellation network and a self-adaptation adjusting structure, wherein the amplitude-phase cancellation network comprises a coupler, an adjustable gain amplifier, an analog phase shifter, a power amplifier, a matched load and a attenuator, the aim that the transmitting chain is coupled with part of energy is achieved, amplitude phase adjustment is performed on a coupling signal, then, the amplitude of a received link coupler and the amplitude of a received same-frequency interference signal are approximately equal, the phase of the received link coupler and the phase of the received same-frequency interference signal are approximately opposite, finally, the amplitude of the received same-frequency interference signal is restrained to be on a lower level, and therefore the received channel carrier-to-noise ratio is improved. The self-adaptation adjusting structure comprises a coupler, a detector, a comparator matched load and a gain adjustable amplifier, the amplitude of the received same-frequency interference signal set on a parallel comparator public reference end is restrained to be the target level detection voltage, and a loop self-adaptation adjusting structure can automatically adjust the adjustable gain amplifier and the analog phase shifter in the amplitude phase cancellation network.

Description

technical field [0001] The invention relates to a topology structure of a cancellation network, in particular to an adaptive four-port cancellation network including an amplitude phase cancellation network and an adaptive adjustment structure, and belongs to the field of microwave design. Background technique [0002] The micro-displacement transceiver channel is the same frequency, simultaneous, and same antenna working system, so the transmitted signal will leak into the receiving channel through the circulator, causing the receiving channel to saturate, deteriorating the signal-to-noise ratio of the receiving channel to the useful signal, and affecting the final system measurement Accuracy; or the measurement distance of the whole system is very small, which cannot be applied in practical engineering. In order to suppress the signal leaked from the transmit signal to the receive channel through the circulator in the receive channel, the method adopted is to couple a certa...

AI Technical Summary

Problems solved by technology

The traditional ultra-high isolation circulator has a steady-state isolation of 75dB from the receiving port to the transmitting port, and the isolation is relatively low. In some occasions where the measurement distance is required to be high, it is very limited, which affects the measurement distance of the system.

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