Research On Key Techniques Of MIMO Radar Based On Electromagnetic Environment Perception

As a new type of radar technology, MIMO radar has strong ability of interceptresistance and high target estimation resolution. Compared with traditional phased arrayradar, MIMO radar also showed better performance and survivability in the face of the threatof stealth technology and anti-radiation technology. With the rapid development of radartechnology, many kinds of interference technology have come out, working environment ofradar has become increasingly severe. Electromagnetic environment sensory MIMO(EES-MIMO) radar is the combination of transform domain communication system (TDCS)technology and MIMO radar technology.In order to improve the performance of MIMO radar estimation under the backgroundof colored noise, in this paper, we design an EES-MIMO radar. The workflow of the newtype of radar system is similar to TDCS’s: environment spectrum perception, targetamplitude spectrum planning, waveform design, sending and receiving waveform and targetestimation. The basic idea is to reduce the correlation between the waveform andinterference by designing and launching MIMO radar waveform whose frequency isdifferent from environmental interference. Its final destination is to improve the detectionprecision under the background of colored noise.Environment interference frequency estimation is an important link of EES-MIMOradar, cross spectrum estimation method has excellent properties of the observation noiseresistance. The MIMO radar has multiple receiving channels; it has natural conditions ofadopting the cross spectrum estimation method. DFCW can design a set of orthogonalwaveform whose frequency band is same. By choosing the frequency code we can adjust thespectrum of the waveform flexibly. It has ability to become the EES-MIMO radar waveformwhose spectrum is similar to the target amplitude spectrum. In this paper, electromagneticenvironment perception of EES-MIMO radar is designed with the cross spectral estimationand the DFCW is designed to be its waveform. This article expounds the working process, the interference resistance principle and thesystem architecture of EES-MIMO radar. In terms of environmental spectrum perception,cross spectrum Levinson narrow-band interference AR model spectrum sensing algorithmand cross spectrum TLS-ESPRIT(Total least squares-Estimation of Signal Parameters viaRotational Invariance Technique) harmonic interference frequency estimation algorithmhave been studied, the principles of amplitude spectrum creating are also given respectively.The simulation and analysis point out that these two algorithms can well satisfy the demandof the EES-MIMO radar interference spectrum perception. In terms of waveform design, thispaper proposes a method of extreme disturbance particle swarm DFCW EES-MIMO radarwaveform design. Simulation shows that this method can get excellent orthogonalwaveforms whose spectrum is close to the target amplitude spectrum fast. In terms of targetestimation, MIMO-MUSIC algorithm is used as a target estimate method of EES-MIMOradar based on DFCW. Under colored noise background, simulation results show that thisnew type of EES-MIMO radar system has a better target estimation precision than thetraditional MIMO radar.