THE JOURNAL OF KOREAN INSTITUTE OF ELECTROMAGNETIC ENGINEERING AND SCIENCE. 2018 Jun.; 29(6), 457463. http://dx.doi.org/10.5515/kjkiees.2018.29.6.457 ISSN 1226-3133 (Print)ISSN 2288-226X (Online) Sigma-Delta STAP Comparison Between Simulation and Test Result of Sigma-Delta STAP 권보준 Bojun Kwon 요약 ΣΔ-STAP..., ΣΔ-STAP -. SINR,, 12 db. ΣΔ-STAP. Abstract This paper compares the results of ΣΔ-STAP applied to actual radar test data and simulation data. The radar received a target signal from a virtual target generator and the clutter signal from a signal generator in an anechoic chamber. The simulation data were generated from ideal baseband radar signal modeling using the same parameter as that for the test radar. The ΣΔ-STAP results of the test and simulation data are similar in terms of the target signal shape and noise level. The SINR(Signal-to-Interfrence-plus-Noise Ratio) loss also had similar aspects, but the simulation result shows 12 db higher SINR loss than the test result. This result verified that the simulation data can be a reasonable alternative test data when the ΣΔ-STAP is applied. Key words: Sigma-Delta STAP, Simulation, Test Result, Airborne Radar. 서론.. MPRF(Medium Pulse Repetition Frequency).. CFAR(Constant False Alarm (Agency for Defense Development) Manuscript received March 13, 2018 ; Revised April 26, 2018 ; Accepted May 8, 2018. (ID No. 20180313-034) Corresponding Author: Bojun Kwon (e-mail: baukwon@add.re.kr) c Copyright The Korean Institute of Electromagnetic Engineering and Science. All Rights Reserved. 457
THE JOURNAL OF KOREAN INSTITUTE OF ELECTROMAGNETIC ENGINEERING AND SCIENCE. vol. 29, no. 6, Jun. 2018. Rate). STAP(Space-Time Adaptive Processing)., - 2.,, [1]. STAP Fully adaptive STAP.. [1].. CPI, DDL(Doppler Domain Localization) [2]. Beamspace STAP [1]., STAP. JDL(Joint Domain Localization) [3] ΣΔ-STAP [4],[5]. [6].,, I/Q. STAP [1].,,. ΣΔ -STAP. ΣΔ-STAP,,,.. ΣΔ-STAP 기법 ΣΔ-STAP 1. T (Σ) (Δ). (boresight)., (null)., ADC(Analog to Digital Convertor),. -. 3 STAP. [7]. 3 그림 1. ΣΔ-STAP Fig. 1. Block diagram of ΣΔ-STAP. 458
Sigma-Delta STAP, 2.. (DOF, Degree of Freedom),.,. 2,,,,,.,, -,,,., (i, j) ΣΔ-STAP. (1). (i, j), m (i, j).,. (i, j).,. (2) (1). (Hermitian transpose). diagonal loading [8] ( ).,.., (3) MSMI(Modified Sample Matrix Inversion)., steering vector. Steering vector, STAP. ΣΔ- STAP, 1, 0., 2. (2) (3) 그림 2. ΣΔ-STAP Fig. 2. Data structure of ΣΔ-STAP. - ΣΔ-STAP. CFAR 459
THE JOURNAL OF KOREAN INSTITUTE OF ELECTROMAGNETIC ENGINEERING AND SCIENCE. vol. 29, no. 6, Jun. 2018.., 2( ) ΣΔ-STAP. =2, =8, =2, 2, (Chebyshev).. 시험환경및시뮬레이션구성.,.. 3-1 시험환경 3.,.. - (4) (narrow-band). cos sin (4),,,. sin cos...,.,,. SNR(Signal-to-Noise Ratio) 30 db, CNR(Clutter-to-Noise Ratio) 40 db 2. 4. db - 5357. (, ) (31, 59).. 3-2 시뮬레이션구성. 그림 3. Fig. 3. Test configuration. (a) 그림 4. (a) (b) Fig. 4. An example of test result(a) and simulation result(b). (b) 460
Sigma-Delta STAP... CPI(Coherent Processing Interval),,. /.,. (4). CPI (eclipse). -....,. ADC DDC(Digital Down Conversion). 4.,,,. 4,,.. ΣΔ-STAP 적용결과비교 ΣΔ-STAP. ΣΔ-STAP - SINR (Signal-to-Interference-plus-Noise Ratio Loss). -.,,. SINR. 4-1 ΣΔ-STAP 처리된거리 - 도플러맵비교 -, ΣΔ-STAP -. 5.,, -, ΣΔ-STAP -. - 2935, 32. 1 33. 31, 33. - 32, 33,. CPI (a) - (a) Range-Doppler map of test data (c) ΣΔ-STAP - (c) ΣΔ-STAP result of test data (b) - (b) Range-Doppler map of simulation data (d) ΣΔ-STAP - ) (d) ΣΔ-STAP result of simulation data) 그림 5. ΣΔ-STAP - Fig. 5. Comparison of ΣΔ-STAP result. 461
THE JOURNAL OF KOREAN INSTITUTE OF ELECTROMAGNETIC ENGINEERING AND SCIENCE. vol. 29, no. 6, Jun. 2018.. ΣΔ-STAP -. 20 db, 18 db., 32. 8 db., CPI. 4-2 SINR 손실비교 STAP SINR. SINR SNR SINR. (5). SINR 12 db, STAP. SINR 0 db,.,. 30 SINR. 6., SINR.. 32, 3. ±3 1 db, (5) 그림 6. SINR Fig. 6. Comparison of SINR loss. 2 db SINR. SNR,,,.. 결론 ΣΔ-STAP., ΣΔ-STAP -. SINR,, 12 db. ΣΔ-STAP.,.,, ADC 462
Sigma-Delta STAP,. References [1] J. Ward, "Space-time adaptive processing for airborne radar," MIT Lincoln Laboratory, Technical Report 1015, 1994. [2] V. Madisetti, "Space-time adaptive processing for airborne surveillance radar," in The Digital Signal Processing Handbook - Wireless, Networking, Radar, Sensor Array Processing, and Nonlinear Signal Processing, CRC Press, 2010. [3] H. Wang, L. Cai, "On adaptive spatial-temporal processing for airborne surveillance radar systems," IEEE Transactions on Aerospace and Electronic Systems, vol. 30, no. 3, pp. 660-670, Jul. 1994. [4] R. D. Brown, M. C. Wicks, Y. Zhang, Q. Zhang, and H. Wang, "A space-time adaptive processing approach for improved performance and affordability," in Proceedings of the 1996 IEEE National Radar Conference, Ann Arbor, MI, 1996, pp. 321-326. [5] R. D. Brown, R. A. Schneible, M. C. Wicks, H. Wang, and Y. Zhang, "STAP for clutter suppression with sum and difference beams," IEEE Transactions on Aerospace and Electronic Systems, vol. 36, no. 2, pp. 634-646, Apr. 2000. [6] M. A. Richards, Fundamentals of Radar Signal Processing, McGraw-Hill, Inc., 2005. [7],,,, " GMTI sigma-delta STAP,", 28(4), pp. 336-346, 2017 4. [8] B. D. Carlson, "Covariance matrix estimation errors and diagonal loading in adaptive arrays," IEEE Transactions on Aerospace and Electronic Systems, vol. 24, no. 4, pp. 397-401, Jul. 1988. 2011 2: ( ) 2013 2: () 2013 4: [ 주관심분야 ] 463