THE JOURNAL OF KOREAN INSTITUTE OF ELECTROMAGNETIC ENGINEERING AND SCIENCE. 2018 May; 29(5), 375382. http://dx.doi.org/10.5515/kjkiees.2018.29.5.375 ISSN 1226-3133 (Print)ISSN 2288-226X (Online) Analysis of Adaptive Side-Lobe Canceller Algorithm for Fully Digital Active Array Radar 양우용 박민규 홍성원 김찬홍 Woo-Yong YangMin-Kyu ParkSung-Won Hong*Chan-Hong Kim* 요약...,..,. Abstract To eliminate strong jamming signals, a radar acquires a relatively weak target signal by using a side-lobe canceller (SLC) algorithm. This paper presents a novel adaptive SLC algorithm that is applicable to a fully digital active array radar. First, a covariance matrix is obtained from the SLC beam. Then, an adaptive SLC coefficient is extracted after calculating the correlation matrix between the main beam signal and the SLC beam signal. Finally, the target signal is estimated and the jamming signal is removed through the operation with the main beam signal. The application results from simulated radar signals demonstrated that the proposed algorithm is effective in an SLC system. Moreover, we analyzed various considerations and improved systematic usability. Key words: Adaptive SLC Coefficient, Correlation Matrix, Covariance Matrix, Fully Digital Active Array Radar, Jamming Signal, Side-Lobe Canceller(SLC). 서론 (radar) (radio detecting and ranging),,. (Hanwha Systems Co., Ltd.) *(Agency for Defense Development, ADD) Manuscript received February 28, 2018 ; Revised April 27, 2018 ; Accepted May 11, 2018. (ID No. 20180228-028) Corresponding Author: Woo-Yong Yang (e-mail: w.y.yang@hanwha.com) c Copyright The Korean Institute of Electromagnetic Engineering and Science. All Rights Reserved. 375
THE JOURNAL OF KOREAN INSTITUTE OF ELECTROMAGNETIC ENGINEERING AND SCIENCE. vol. 29, no. 5, May 2018.,.,. Gradient, [1],[2]. LCMV(Linear Constrained Minimum Variance)., [3][5]. [6].,.,,.,.,.,.,... 완전디지털능동배열레이다개요 2-1 완전디지털능동배열레이다구성.,.,.,,.,. 1. 2-2 디지털다중빔형성 [7]. 그림 1. Fig. 1. Structure of fully digital active array radar. 376
(1) m, s(m) m (complex envelope). n(m), a(u,v) (steering vector). 2 k,, y k. N z k. (2) M, a H (u k,v k ) (hermition), X n n., (side lobe).. 적응형부엽제거알고리즘.,,. 3, 4. s k. min min (3) z k, E{}.. (4),,. 3-1 부엽제거수신빔을이용한공분산행렬계산 (1 단계 ) 1 그림 2. Fig. 2. Structure of beam formation in digital transceiver module. 그림 3. Fig. 3. Structure and step of adaptive SLC algorithm. 377
THE JOURNAL OF KOREAN INSTITUTE OF ELECTROMAGNETIC ENGINEERING AND SCIENCE. vol. 29, no. 5, May 2018.. MLE(Maximum Likelihood Estimation) [8],[9]. (5) M (training), M. X(m),. 4 4 [10].,,. 3-2 주빔과부엽제거수신빔을이용한상관행렬계 산 (2 단계 ) 2. (6) M,.,.. 3-3 공분산행렬과상관행렬을이용한적응형부엽 제거빔형성계수계산 (3 단계 ) 1 2 W k. (7). k k. 3-4 최종다중수신빔계산 (4 단계 ) 4. (8) 2-2 z k 3.. 알고리즘적용및분석 4-1 시뮬레이션및최종수신빔정보추출,. 1. 56, 48, 16 4. (training), #51#1000.. 4 378
표 1., Table 1. Simulation parameters of the target, jammer and radar. Section of target signal Incidence angle of target signal (theta, phi) #801#805 sample (15,0 ) Number of jammer 4 Section of jammer signal Training section Incidence angle of jammer signal (theta, phi) JSR Structure of radar array #1#1000 sample #1#50 sample (15, 20 ), (-20, 30 ), (30, 30 ), (-25, -30 ) 23 db 1 /., #801#805., 20,, SLC. 4-2 레이다체계에적용하기위한고려사항분석.,,. 4-1 4, 4. 4-2 1 7.5402. 7.5402 5 2. ( 6).,, 4 4. 그림 4. / ( 1 ) Fig. 4. Result before/after processing with the proposed algorithm(when the variable in Table 1 are applied). 그림 5. () Fig. 5. Concurrent incident condition of jammer direction. 379
THE JOURNAL OF KOREAN INSTITUTE OF ELECTROMAGNETIC ENGINEERING AND SCIENCE. vol. 29, no. 5, May 2018. (a) null (a) Case when jammer does not enter in the null direction 그림 6. / ( 7.5402 ) Fig. 6. Result before/after processing with the proposed algorithm(when incident angle of jammer is 7.5402 ).,.. 7, null. 7(a) null, 140 db. 7(b) 1 SLC null,,., null. (b) null (b) Case when jammer enter in the null direction 그림 7. SLC Fig. 7. Original SLC pattern and final receive pattern... 8 7 4, null (u=0.895). null, 8(b). null, null. null, trade off. 380
References (a) null (a) Case when jammer does not enter in the null direction (b) null (b) Case when jammer enter in the null direction 그림 8. SLC Fig. 8. Modified SLC pattern and final receive pattern.. 결론.,... [1],,,, "," 2009, pp. 731-734, 2009. [2] D. P. Bertsekas, Nonlinear Programming, Belmont, Massachusetts, Athena Scientific, 1995. [3],,,, " FPGA,", 26(4), pp. 424-434, 2015 4. [4] L. Griffiths, C. Jim, "An alternative approach to linearly constrained adaptive beamforming," IEEE Transactions on Antennas and Propagation, vol. 30, no. 1, pp. 27-34, Jan. 1982. [5],,,,, ",", 26(3), pp. 317-325, 2015 3. [6] S. H. Talisa, K. W. O haver, T. M. Comberiate, M. D. Sharp, and O. F. Somerlock, "Benefits of digital phased array radar," in Proceedings of the IEEE, Mar. 2016, vol. 104, no. 3, pp. 530-543. [7] A. Farina, Antenna-Based Signal Processing Techniques for Radar System, Boston, Artech House, 1992. [8] L. S. Reed, J. D., Mallett, and L. E. Brennan, "Rapid convergence rate in adaptive arrays," IEEE Transactions on Aerospace and Electronic Systems, vol. 10, no. 6, pp. 853-863, Nov. 1974. [9] C. H. Gierull, "Fast and effective method for low-rank interference suppression in presence of channel error," Electronic Letters, vol. 34, no. 6, pp. 518-520, Mar. 1998. [10],,,,, " sidelobe canceller Spatio-temporal,", 11(3), pp. 329-336, 2000 4. 381
THE JOURNAL OF KOREAN INSTITUTE OF ELECTROMAGNETIC ENGINEERING AND SCIENCE. vol. 29, no. 5, May 2018. 2005 2: ( ) 2007 2: () 2015 2: () 2007 1: PGM [ 주관심분야 ] /,, / 2010 2: () 2012 2: () 2017 2: ( ) 2017 12: [ 주관심분야 ], / 2016 8: () 2016 7: PGM [ 주관심분야 ], 1991 2: ( ) 1993 2: () 2008 8: () 1993: [ 주관심분야 ] SAR /, /,,, 382