• 한국통신학회논문지
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• 제19권7호
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• pp.1407-1413
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• 1994

레이다에서 정확한 표적 정보를 얻기 위해서는 우선 클러터나 간섭 신호를 효율적으로 제거하고 표적을 검출하여야 한다. 본 논문에서는 신호를 제한 조건에 의해 구별되는 직교 부공간으로 투사함으로써 최분산 기분을 갖는 최적 검출기를 제한 조건을 갖지 않는 검출기로 변형하였다. 제안된 방법은 기존의 최적검출 알고리듬과 등가이며, 역행렬을 구하지 않고서도 빠른 수렴속도를 얻기위한 Gram-Schmidt 적교화가 가능한 구조를 가지게 된다. 모의 실험을 통해 제안된 검출기가 공간과 주파수 영역에서 적응적으로 잘 동작하고 있음을 보였다.

• ETRI Journal
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• 제31권2호
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• pp.193-200
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• 2009

In this paper, we study the performance of subspace-based multiuser detection techniques for multicarrier code-division multiple access (MC-CDMA) systems. We propose an improvement in the PASTd algorithm by cascading it with the classical Gram-Schmidt procedure to orthonormalize the eigenvectors after their sequential extraction. The tracking of signal subspace using this algorithm, which we call OPASTd, has a faster convergence as the eigenvectors are orthonormalized at each discrete time sample. This improved PASTd algorithm is then used to implement the subspace blind adaptive multiuser detection for MC-CDMA. We also show that, for multiuser detection, the complexity of the proposed scheme is lower than that of many other orthogonalization schemes found in the literature. Extensive simulation results are presented and discussed to demonstrate the performance of the proposed scheme.

• 한국통신학회논문지
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• 제24권9B호
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• pp.1785-1794
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• 1999

Affine projection 알고리즘은 RLS보다 적은 계산량으로 LMS보다 우수한 수렴성능을 나타낸다. 그러나 affine projection 알고리즘은 역행렬 연산을 필요로 하기 때문에 여전히 LMS에 비해 과중한 계산을 필요로 한다. 본 논문에서는 affine projection 알고리즘을 분석하여 이 알고리즘이 Gram-Scheme 구조로 해석될 수 있음을 보이고 이를 이용하여 NLMS와 비슷한 계산량으로 affine projection 알고리즘을 근사적으로 구현할 수 있는 새로운 알고리즘을 제안하였다. 제안한 방법은 NLMS와 비슷한 계산량을 가지면서 기존의 affine projection 알고리즘과 비슷한 수렴성능을 나타내었다.

• 전자공학회논문지B
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• 제31B권7호
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• pp.58-65
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• 1994

A recursive on-line algorithm for orthogonal ARMA identification is proposed for linear MIMO systems with unknown parameters time delay and order. This algorithm is based on the Gram-Schmidt orthogonalization of basis functions, and extended to a recursiveform by using new functions of two dimensional autocorrelations and crosscorrelations of inputs and outputs. This proposed algorithm can also cope with slowly time-varying or order-varying systems. Various simulations reveal the performance of the algorithm.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.58-63
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• 1993

A recursive on-line algorithm with orthogonal ARMA identification is proposed for linear MIMO systems with unknown parameters, time delay, and order. This algorithm is based on the Gram-Schmidt orthogonalization of basis functions, and extended to a recursive form by using new functions of two dimensional autocorrelations and cross-correlations of inputs and outputs. The proposed algorithm can also cope with slowly time-varying or order-varying systems. Various simulations reveal the performance of the algorithm.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.548-553
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• 1992

In this paper and recursive version of orthogonal ARMA identification algorithm is proposed. The basic algorithm is based on Gram-Schmidt orthogonalization of automatically selected basis functions from specified function space, but does not require explicit creation of orthogonal functions. By using two dimensional autocorrelations and crosscorrelations of input and output with constant data length, identification algorithm is extended to cope slowly time-varying or order-varying delayed system.

• 전자공학회논문지B
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• 제31B권4호
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• pp.48-54
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• 1994

A recursive on-line algorithm with orthogonal ARMA identification is proposed for linear systems with unkonwn time delay, order, and parameters. The algorithm is based on the Gram-Schmidt orthogonalization of basis functions, and extendedto recursive form by using two dimensional autocorrelations and crosscorrelations of input and output with constant data length. The proposed algorith can cope with slowly time-varying or order-varying delayed system. Various simulations reveal the performance of the algorithm.

• Communications for Statistical Applications and Methods
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• 제2권1호
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• pp.48-54
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• 1995

A direct method for fitting analysis-of-variance models to unbalanced data is presented. This method exploits sparsity and rank deficiency of the matrix and is based on Gram-Schmidt orthogonalization of a set of sparse columns of the model matrix. The computational algorithm of the sum of squares for testing estmable hyphotheses is given.

• ETRI Journal
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• 제28권2호
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• pp.155-161
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• 2006

In this paper, we introduce an escalator (ESC) algorithm based on the least squares (LS) criterion. The proposed algorithm is relatively insensitive to the eigenvalue spread ratio (ESR) of an input signal and has a faster convergence speed than the conventional ESC algorithms. This algorithm exploits the fast adaptation ability of least squares methods and the orthogonalization property of the ESC structure. From the simulation results, the proposed algorithm shows superior convergence performance.

• 전자공학회논문지B
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• 제29B권1호
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• pp.26-33
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• 1992

This paper presents lattice structure of bilinear filter and the conversion equations from lattice parameters to direct-form parameters. Billnear models are attractive for adaptive filtering applications because they can approximate a large class of nonlinear systems adequately, and usually with considerable parsimony in the number of coefficients required. The lattice filter formulation transforms the nonlinear filtering problem into an equivalent multichannel linear filtering problem and then uses multichannel lattice filtering algorithms to solve the nonlinear filtering problem. The lattice filters perform a Gram-Schmidt orthogonalization of the input data and have very good easily extended to more general nonlinear output feedback structures.