Research On Rf Cancellationtechnologyof Fmcw Radar

In the development process of helicopter anti-collision system, the microwave helicopter crash radar technology has become an important development direction of helicopter anti-collision technology. At present, the microwave radar for the field of helicopter anti-collision mainly adopts the pulse type radar. However, the application of prominent frequency modulation continuous wave(FMCW) type radar has been suppressed. Thereason is that the continuous wave type radar has existed a fatal weakness: the signal leakage. People has proposed all along a number of effective ways to solve this problem, and in the helicopter that is small space, the structure compact weapons platform,these methods are difficult to meet the need of single antenna FMCW microwave helicopter crash radar engineering applications. However, with the development of modern microwave solid-state device technology,a number of methods have been proposed,RF cancellation technology will be the key to achieve the single antenna FMCW microwave helicopter crash radar practional utilization in the future.This paper is based on this application background,to RF cancellation technology launched comprehensive research, and carried out an experiment in the single antenna millimeter-wave FMCW radar front-end using RF cancellation technology.The measurement shows a leakage suppression of more than 25 dB over a 100 MHz sweeping bandwidth at 10.5GHz.Firstly, this paper briefly introduces the basic principle and the basic characteristics of the microwave FMCW radar, and detailed introduces the principle of each solutions methods of signal leaking problem. It describes and detailed analysis the basic principle of RF cancellation technology theoretically, put forward the performance evaluation of RF cancellation performance. Based on the above principles of RF cancellation technology analysis and research on the microwave band, formulated the RF cancellation experimental system solutions, and the principle of experiments cheme analysis and cancellation performance analysis, for further specific design of the RF cancellation experiment system provides theory basis. Finally, this paper introduced the experimental system hardware alignment process is discussed, and proposed the testscheme of experiment system, and detailed tested the RF cancellation experiment system, and given the test results, and summarized the factors affect cancellation performance in this experiment.