Pseudo-random Code Modulated Continuous Wave Radar Signal Leakage Suppressor Pathway

Compared with pulse radar in the same range, pseudo random code modulationcontinuous wave (CW) radar is small in size and light in weight. Moreover, pseudorandom code modulation CW radar belongs to low probability of intercept (LPI) radar,which has better battlefield survivability. Therefore, pseudo random code modulationCW radar gets development opportunity currently.Nevertheless, because CW radar works in the mode of continuous transmitting andreceiving, the leakage from transmitting signal to receiving channel exists. High leakagesignal makes IF amplifier saturate, which causes such problems as the decrease ofreceiving sensitivity, or the occurrence of false targets and so on. In the field of radartechnology, it is important to solve the problem of transmitter receiver isolationeffectively so as to suppress leakage signal to enough low level and satisfy the designrequirements of radar.Several leakage signal suppression methods, microwave cancellation, IFcancellation, pseudo random code correlation suppression technology and so on, areintroduced, with their advantages and disadvantages compared. With engineeringpractice considered and the indexes of radar demonstrated in detail, an effective leakagesignal suppression method based on the correlation of pseudo random code is proposed.It is easy to implement the method in engineering and the device is small in size. At thesame time, correlator is tested, with its performance analyzed.On the basis of experiment, leakage signal suppressor is designed in detail andapplied to engineering system. Suppressor is tested in the system. Test results show thatit satisfies the requirements of the system. System test and single machine test arecompared. Some disadvantages and contents which need to be improved are given.