V.S. Chernyak - Dr. Sc. (Eng.), Professor, Moscow Aviation Institute and Bauman Moscow State Technical University (National Research Universities). E-mail: chernyak@mail.ru

Known methods for adaptive interference cancellation in receivers, which made a good showing for sidelobe interference cancellation, are ineffective for mainlobe interferences. If there are no differences in signal and interference directions of arrival, interference cancellation is accompanied with signal suppression. The above difficulty has been overcome in Multisite (Multistatic) Radar Systems (MSRSs). If baselengths between stations are large enough, so that received signal fluctuations at the inputs of different stations are uncorrelated, effective interference cancellation without signal suppression is possible even when a target and an interference source coincide in space. MIMO radars with colocated antennas can simultaneously transmit a set of orthogonal waveforms with arbitrary phases and amplitudes. It is stated in a series of publications, that thanks to this feature MIMO radars can cancel interference without signal suppression when signals and interference directions of arrival are equal (unlike radars with conventional phased arrays). Main attention in the article is paid to the synthesis and analysis of optimal signal detection algorithms in a background of mainlobe interferences for MIMO radars (according to the likelihood ratio criterion). The general case is considered where signals and interferences impinge the receiving array inputs as well as a scheme with preliminary matched filtration and separation of orthogonal signals. It is shown that, as distinct from MSRSs, interference cancellation in MIMO radars (as in radars with conventional phased arrays) is accompanied with signal suppression if directions of signal and interference arrival are equal or very close to each other. Signal phase differences caused by signal propagation from a transmitting array to a target (as well as signal initial phase differences) have no effect. Only phase differences caused by signal and interference propagation from a target and an interference source to receiving array elements are important.

 

1. SHirman JA.D., red. Teoreticheskie osnovy radiolokacii. M.: Sov. radio. 1970.
2. SHirman JA.D., Manzhos V.N. Teorija i tekhnika obrabotki radiolokacionnojj informacii na fone pomekh. M.: Radio i svjaz. 1981.
3. CHernjak V.S. Mnogopozicionnaja radiolokacija. M.: Radio i svjaz. 1993 (per. na angl. Chernyak V.S. Fundamentals of Multisite Radar Systems. Multistatic Radars and Multiradar Systems. Gordon and Breach Science Publishers. 1998).
4. Chernyak V.S. About the «New» Concept of Statistical MIMO Radar. Proc. of Int. Radar Symp. IRS 2007. Cologne. Germany. September 2007.
5. Chernyak V.S. On the Concept of MIMO Radars. Proc. of IEEE Int. Radar Conf. Radar 2010. WashingtonDC. USA. May 2010. P. 327-332.
6. CHernjak V.S. O novykh i starykh idejakh v radiolokacii // Uspekhi sovremennojj radioehlektroniki. 2011. № 2. S. 5-20.
7. Rabideau D.J., Parker P.A. Ubiquitous MIMO Multifunction Digital Array Radar - and the Role of Time-Energy Management in Radar. Project Report DAR-4. Lincoln Laboratory Massachusetts Institute of Technology. 2004. 
8. URL http://oai.dtic.mil/oai/oai-verb=getRecord&metadataPrefix=html&identifier=ADA421233.
9. Li Jian and Stoica Petre, editors MIMO Radar Signal Processing. New York: Wiley. 2009.
10. Deng HaiAdaptive Signal Processing for Jammer Suppression Using MIMO Radar. Proc. Int. Symp. on Antennas and Propagation AP-S/URSI. July 2011. Spokane. Wa. USA. P. 389-392.
11. Deng Hai and Himed Braham Interference Mitigation Processing for Spectrum Sharing Between Radar and Wireless Communications Systems // IEEE Trans. on AES. July 2013. V. 49. № 3. P. 1911-1919.
12. CHernjak V.S. Prostranstvenno-chastotnaja filtracija signalov na fone stokhasticheskikh pomekh v mnogokanalnykh priemnykh sistemakh // Radiotekhnika i ehlektronika. 1973. T. 18. № 5. S. 959-969.
13. CHernjak V.S. Obnaruzhenie signalov v MIMO RLS // Uspekhi sovremennojj radioehlektroniki. 2014. № 7. S. 35-48.
14. Dwyer P.S, Waugh F.V. On errors in matrix inversion // Journal Amer. Statistical Association. 1953.V. 48. № 262. P. 289-319.
15. Li Yongzhe, Vorobyov Sergiy.A., Hassanien Aboulnasr MIMO Radar Capability of Powerful Jammers Suppression // Proc. Int. Conf. on Acoustic, Speech and Signal Processing (ICASSP). Florence. Italy. May 2014. P. 5314-5318.