Patent ID: 11860259
Assignee: DALIAN UNIVERSITY OF TECHNOLOGY
Field: Telecommunications (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 2:
3. A RF leakage interference cancellation method using the optical-electronic integrated RF leakage interference cancellation system for CW radar of claim 1, wherein comprising the following steps:
the first step, the low power target signal received by the transceiver antenna inputs to the cable link via the electronic circulator; the high power RF leakage interference signal from the transmitter source of continuous wave via the electronic circulator also inputs to the cable link; the target signal and the RF leakage interference signal transmit through the cable to the input port of the electronic coupler;
the second step, the tapped reference signal from the continuous wave source in the transmitter via the electro-optic modulation unit is modulated on the lightwave form the laser; the optically carried microwave signal transmits through the optically enabled microwave phase shift unit, the optically enabled microwave time delay unit and the optically enabled microwave amplitude tuning unit in sequence; the optically enabled microwave phase shift unit exerts the phase shift to the optically carried microwave signal from the electro-optic modulation unit; the optically enabled microwave time delay unit exerts the time delay to the optically carried microwave signal from the optically enabled microwave phase shift unit; the optically enabled microwave amplitude tuning unit exerts the amplitude adjustment to the optically carried microwave signal from the optically enabled microwave time delay unit; the optically carried microwave signal with the phase shift, time delay and amplitude adjustment feeds to the photo detection unit, where the optical-to-electronic conversion is completed and then the cancellation signal is output;
the third step, the cancellation signal from the optical-to-electronic conversion unit and the leakage interference are combined via the electronic coupler, where the cancellation between the two signals is completed;
the fourth step, the feedback control unit monitors the residual leakage signal from the electronic coupler and generates the control signal via the data processing and algorithm; the control signal adjusts the phase change, time delay change and amplitude change of the optically carried microwave signal in optical domain, and the photo detection unit generates the cancellation signal;
the fifth step, the cancellation signal inputted to the electronic coupler has the following relationship with the leakage interference signal, the out of phase, the same amplitude and the matching time; then the complete cancellation occurs in the process of circuit closing by the electronic coupler; the RF leakage signal is cancelled, and the target signal received by the transceiver antenna is recovered.