Journal of the Institute of Electronics Engineers of Korea SP (대한전자공학회논문지SP)

The Institute of Electronics and Information Engineers (대한전자공학회)
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Improving the Performance of the Capon Algorithm by Nulling Elements of an Inverse Covariance Matrix

공분산 역행렬 원소 제거 기법을 이용한 Capon 알고리듬의 성능 개선

  • Kim, Seong-Min (Department of Electronics and Computer Engineering, Chungnam National University) ;
  • Kang, Dong-Hoon (Department of Electronics and Computer Engineering, Chungnam National University) ;
  • Lee, Yong-Wook (Department of Electronics and Computer Engineering, Chungnam National University) ;
  • Nah, Sun-Phil (ADD) ;
  • Oh, Wang-Rok (Department of Electronics and Computer Engineering, Chungnam National University)
  • Received : 2011.07.08
  • Accepted : 2011.08.11
  • Published : 2011.09.25
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Abstract

It is well known that the Capon algorithm offers better resolution compared to that of the FM (Fourier method) algorithm by minimizing the total output power while maintaining a constant gain in the look direction. Unfortunately, the DoA (Direction of Arrival) estimation performance of the Capon algorithm is drastically degraded when the SNR of received signal is low and thus, it cannot distinguish among signal sources which have similar incidence angles. In this paper, we propose a novel scheme enhancing the resolution of the Capon algorithm by ing all rows except the first row of an inverse covariance matrix.

Capon 알고리듬은 지향방향에 대하여 일정한 이득을 유지하면서 배열의 출력을 최소화 시키므로 FM (Fourier method) 알고리듬에 비하여 우수한 분해능 (resolution)을 제공한다. 그러나 Capon 알고리듬의 DoA (Direction of Arrival) 추정 성능은 입사 신호의 SNR (signal-to-noise ratio)이 낮은 경우 급격히 저하되는 문제가 있어 신호원들의 입사각이 유사한 경우 각각의 신호원을 구분하지 못하는 문제가 있다. 본 논문에서는 Capon 알고리듬에서 사용되는 공분산 역행렬의 원소를 제거하는 기법을 이용하여 수신 신호의 SNR이 낮은 환경에서 보다 나은 분해능을 제공하는 개선 방안을 제안한다.

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References

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