Performance Evaluation Technology On MIMO Radar

Phased array radar usually has some disadvantages.For example,when transmitting the signals,energy can only radiate in one particular direction,strong energy may make the radar itself exposed to enemy's detection equipment;when working at a low elevation angle,strong clutter power may cause the radar receiver to saturate and fail to work properly;MIMO radar can only illuminate a narrow area each time,this determines that it cannot monitor the entire airspace at the same time.On the basis of phased array radar,only by changing the mode of transmitted signals,so that they are mutually orthogonal,all problems can be well solved.That is centralized MIMO(Multiple-Input Multiple-Output)radar discussed in this paper.MIMO radar not only inherits the advantages of phased array radar,at the same time it also has its unique characteristics: for example,(1)waveform diversity makes the signal processing different,so angle measurement can be realized in transmit-receive way,that improves measuring accuracy;(2)forming multi-beams at a time,MIMO can get more impulses.Those distinctions make MIMO radar perform better than phased array radar in aspects as anti-intercept,speed resolution and anti-interference.So the work of this thesis is focused on the basic concept of MIMO radar and its performance evaluation to that of the corresponding phased array radar(all are the same to MIMO radar except the signals).This thesis firstly introduces the basic principles and characteristics of MIMO radar,and then we analyze the characteristics of MIMO radar in aspects of anti-intercept,speed resolution and anti-interference.Secondly,the echo model of MIMO radar is deduced in detail,and the basic process of MIMO radar echo processing is given in the thesis.On the model we do research on some key signal processing algorithms;and then we prove the consistency of the two methods of MIMO echo processing and discuss the comparison of the two operations,and then we select a small amount of computing method and do the comparison to that of phased array radar.Thirdly,the thesis analyses single pulse angle measurement methods of MIMO radar.Two-beam amplitude ratio method and sum-difference beam phase ratio method are the best in terms of accuracy and the amount of calculation,and then we apply it to MIMO radar.According to the characteristics of MIMO radar,angle measurement can be divided into the transmitter,the receiver and the transceiver,so all the single pulse angle measurement methods of MIMO radar are analyzed and the conclusions are given,too.Finally,we discuss the effect of signal diversity on the expansion of the aperture,and the effect on angle measurement.Finally,this thesis analyses the detection power and clutter suppression of MIMO radar.Phased array radar's energy is concentratedly emitted while MIMO radar has longer dwell time,under the combined effect of the two factors,we get the conclusion that the distance of MIMO radar may be larger in sparse array condition,and then the MTI and MTD methods on clutter suppression are discussed briefly.