2차패턴 구속의 LCMV 빔형성 방법 연구

이관형,Lee, Kwan-Hyeong 한국정보전자통신기술학회 2022 한국정보전자통신기술학회논문지 Vol.15 No.5

The STAP system suppresses clutter and jamming of the radar signal, but required a large number of samples for optimal performance. A large number of samples increases the signal processing computation. Therefore, there is need for a transformation method for reducing the signal rank. The LCMV beamforming method can easily set the distortion-free-constraint in the direction of arrival, and the beamforming scaling is excellent, so that overall rank can be reduced. In this study, the information of target is estimated using the proposed quadratic pattern constraints(QPC) and LCMV beamforming methods. The proposed method can perform beam pattern control in a desired direction according to the number of constraint conditions as a secondary pattern constraint condition. Through simulation, the performance of the propose method is verified. As a result on th simulation, the desired target was estimated when the proposed method had an angular resolution of 10 degrees or more, but it was not possible to accurately estimate the desired target when the angular resolution was less than 10 degrees.

오 경보 확률 감소를 위한 효율적인 임계치에 대한 연구

이관형,Lee, Kwan-Hyeong 한국정보전자통신기술학회 2015 한국정보전자통신기술학회논문지 Vol.8 No.2

본 논문에서는 레이더 시스템에서 원하는 목표물 추정을 위한 효율적인 임계치 방법을 연구였다. 관심있는 목표물 탐지 검출 방법은 오 경보 확률을 변화 시켜 가면서 원하는 목표물을 추정한다. 이때 오 경보의 확률은 임계치와 밀접한 관계가 있다. 임계치를 낮게 하면 원하는 목표물의 정확도를 향상시킬 수 있지만 잡음 까지 추정하여 효율적인 신호처리 방법이 되지 못한다. 효율 적인 임계치 방법을 제안하여 원하는 목표물을 추정하는 연구 방법을 제안하다. 모의실험을 통해서 기존의 방법과 본 연구에서 제안한 방법을 비교 분석하였다. We have studied an efficient threshold level for desired target detection in radar system in the paper. A desired target searching detection method detects desired target according to changing for false alarm probability. This time, false alarm probability is close relation to threshold level. Low threshold level can improve detection for desired target, but detect noise signal. Therefor, This method is not good one. In this paper, we propose efficient threshold level method in order to estimation for desired target. Through simulation, we are analysis and performance to compare general method with proposal method. We show that proposed method is more good proof than general method.

적응 배열 안테나 빔형성 기법을 이용한 CDMA시스템 성능에 대한 연구

이관형(Lee, Kwan-Hyeong) 한국정보전자통신기술학회 2012 한국정보전자통신기술학회논문지 Vol.5 No.2

본 논문에서는 이동 무선 채널에서 배열 안테나의 빔형성 기법을 이용하여 CDMA시스템의 성능을 분석한다. 적응 배열 빔형성 안테나 기술은 배열 안테나 소자에서 수신된 신호의 크기와 위상을 결합하고, 가중치를 이용하여 각 소자에서의 도래방향 신호를 증대시키는 공간 필터의 기능을 제공한다. 모의실험을 통해서, 본 논문에서는 CDMA페이딩 환경에서의 간섭 신호를 줄이기 위하여 배열 안테나의 빔형성 기법를 이용하여 양방향 채널에서의 비트오류율을 비교 분석 하였다. 모의실험 결과 배열 안테나시스템을 사용함으로써 공간 다이버시티 효과를 얻을수 있고, MAI의 간섭이 감소하여 성능이 향상됨을 나타내었다. This paper is an analysis the performance of CDMA system using array antenna beamforming technique in wireless channels. Adaptive array beamforming antenna technique combine receive signal amplitude with phase in array antenna element, and can be incremental spatial filter function a direction of arrival signal using weight value. Through simulation, in this paper, we were an analysis to compare bit error rate of forward and backward channels using array antenna beamforming technique in order to interference signal decrease of CDMA fading enviroment. The result simulation, we get spatial diversity effect by using array antenna system, and improved the performance to MAI interference decrease.

배열소자 오동작 문제해결을 위한 주파수 영역 알고리즘 연구

이관형(Kwan-Hyeong Lee),송우영(Woo-Young Song),이명호(Myung-Ho Lee) 한국정보기술학회 2010 한국정보기술학회논문지 Vol.8 No.10

In this paper, we proposed a signal recovery method a case when array element is error operation in adaptive array antenna. The main occur to increase a side lobe gain of output pattern a case where element of more one among array element is error operation, and it is not a forming null pattern to incident angle a interference signal. This paper proposal method is recovery signal of a broken array antenna to get inter element phase shift at frequency domain. This paper proposal algorithm is correctly directivity a output pattern to target angle, and proposal algorithm was compensation a loss of array element on forming null pattern to interference signal angle.

다중입력 다중출력 배열 안테나 시스템에서 목표물 방향 추정에 관한 연구

이관형(Kwan-Hyeong Lee) 한국정보기술학회 2012 한국정보기술학회논문지 Vol.10 No.3

This research estimates a direction of arrival(DOA) of target in multi input multi output(MIMO) array antenna system. MIMO array antenna system is classified into two main categories : distribute MIMO array antenna system and colocated MIMO array antenna system. In this paper, we propose an algorithm that exploits the time daly to obtain two corss correlation matrices using colocated MIMO array antenna system. Then we applied singular value decomposition(SVD) technique to achieve the signal subspace matrix. We were analysis of performance that general ESPRIT algorithm and proposed target estimation algorithm through simulation. It was 2dB improved to more proposal algorithm than generally ESPRIT algorithm in target direction of arrival estimation.

차량용 77GH 주파수변조연속파형을 사용한 레이더와 물체사이의 거리 측정 방법

이관형(Lee Kwan Hyeong) 한국정보기술학회 2022 Proceedings of KIIT Conference Vol.2022 No.6

목표물 추정 향상을 위한 수정 선형 예측방법에 대한 연구

이관형(Kwan-Hyeong Lee),주종혁(Jong-Hyuk Joo) 한국정보전자통신기술학회 2016 한국정보전자통신기술학회논문지 Vol.9 No.4

본 연구에서는 수정 선형예측방법으로 목표물의 신호를 정확히 추정하는 방법에 대해서 연구하였다. 선형예측방법은 임의의 안테나 배열소자를 다른 소자들과 선형 결합하여 도래방향 신호를 추정하는 방법이다. 수정 선형예측방법은 최적 가중치와 사후확률방법을 사용하였다. 모의실험을 이용하여 본 연구에서 제안한 방법과 Bartlett 및 MUSIC방법의 성능을 비교 분석하였다. 모의실험조건은 안테나 배열 소자 9개, 목표물 신호 4개[-5o, 0o, 5o, 10o]에서 방향을 추정한다. 모의실험에서 Bartlett과 MUSIC방법은 목표물 신호를 3개만 추정하였고, 본 연구에서 제안한 방법은 목표물 신호 4개를 모두 추정하였다. 본 연구에서 제안한 방법이 기존의 Bartlett 과 MUSIC방법보다 분해능이 우수함을 나타내었다. In this paper, we studied a modified linear prediction method to estimate target signal correctly. Linear prediction method estimate direction-of-arrival to linear combination for any antenna element and other antenna elements. Modified linear prediction used optimal weight and posterior probability method. Through simulation, we are comparative analysis about the performance of proposed, bartlett and MUSIC method. From simulation, Bartlett and MUSIC method was estimation 3 targets signal, and proposed method estimated 4 targets. We showed the superior performance of the proposed algorithm relative to the classical method in order to estimate of target signals.

기준 신호를 이용한 공액 부 배열 빔 형성 상관 행렬에 대한 연구

이관형(Kwan-Hyeong Lee),송우영(Woo-Young Song),이명호(Myeong-Ho Lee) 한국정보기술학회 2011 한국정보기술학회논문지 Vol.9 No.7

Direction of arrival estimation using smart antenna are used direction of arrival algorithm such as MUSIC and ESPRIT. Generally, Direction of arrival estimation algorithm estimate a desired target signal to separate signal space and noise space using spatial array method. For such a method, it is not efficient at real time processing to increase processing velocity because of eigen decomposition. We can not be estimation direction of arrival of desired signal in case receiving signal element number is more than antenna array element number. This paper estimated a direction of arrival using two virtual sub-array and two beamformer using reference signal. In this paper, we correctly estimated a desired signal in case receiving signal element number is more than antenna array element number. And, we are improved 2° resolution more than general method at direction of arrival estimation.

이차항과 라그랑주 방법을 이용한 도래 방향 추정 적응 빔형성 갱신 가중치에 대한 연구

이관형(Kwan-Hyeong Lee),송우영(Woo-Young Song),이명호(Myeong-Ho Lee) 한국정보기술학회 2011 한국정보기술학회논문지 Vol.9 No.9

In wireless channels, it manyh researchers have studied an adaptive antenna array and direction of arrival(DoA) algorithms in order to correctly estimate the desired signal angle. The adaptive antenna array is used for receiving the desired signal in a specific angle and rejecting the interference signal in other angles. This paper proposed an adaptive beamforming technique for linear array antenna. Weight values in a adaptive beamformer system depends the maximum value of the signal-to-interference noise ratio. In order to obtain the signal in a desired directioin, weight values of the beamformer should be updated at each iteration. In this paper, we proposed a method renewing weight values at each iteration based on a quadratic form and Lagrange multipliers. Through simulation, we compared the proposed method with the existing MUSIC method. This paper proposal method achieved a 3-degree resolution in the estimation of the desired signal angle using an array of 8 element with a half-wavelength spacing.

디지털 빔형성 오차보정 기법을 이용한 목표물 탐지에 대한 연구

이관형(Kwan-Hyeong Lee),송우영(Woo-Young Song),이명호(Myung-Ho Lee) 한국정보기술학회 2010 한국정보기술학회논문지 Vol.8 No.7

In wireless communication, it is difficult to estimation the target if fading occurs due to jamming, clutter, multipath. In this paper, we proposed an error correction method in order to estimation correctly position of the target. We were using an adaptive array antenna. In this paper, we proposed an optimum weight value after antenna error correction in receive signal. And, we were digital beamforming after proposal weight value algorithm in receive signal in order to estimation correctly position of the target. In this paper, we compared proposal algorithm with general algorithm. In this paper, we proposal algorithm give a proof good performance.