• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.4
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• pp.424-434
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• 2015

Adaptive beamforming algorithms have been widely used to remove interference and jamming in the phased array radar system. Advances in the field programmable gate array(FPGA) technology now make possible the real time processing of adaptive beamforming (ABF) algorithm. In this paper, the FPGA based real-time implementation method of adaptive beamforming system(beamformer) in the pre-processor module for active electronically scanned array(AESA) radar is proposed. A compact FPGA-based adaptive beamformer is developed using commercial off the shelf(COTS) FPGA board with communication via OpenVPX(Virtual Path Cross-connect) backplane. This beamformer comprises a number of high speed complex processing including QR decomposition & back substitution for matrix inversion and complex vector/matrix calculations. The implemented result shows that the adaptive beamforming patterns through FPGA correspond with results of simulation through Matlab. And also confirms the possibility of application in AESA radar due to the real time processing of ABF algorithm through FPGA.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.249-252
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• 2001

We, for the first time, propose a novel adaptive beamforming algorithm for smart antenna. The algorithm requires neither spatial knowledge nor reference signal. The algorithm is based on gradient method and its merit is in the simplicity of calculation load while maintaining good performance. Computer simulations are presented to verify the performance.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.2
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• pp.247-250
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• 2001

We, for the first time, propose a novel adaptive beamforming algorithm for smart antenna. The algorithm requires neither spatial knowledge nor reference signal. The algorithm is based on gradient method and its merit is in the simplicity of calculation load while maintaining good performance. Computer simulations are presented to verify the performance.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1642-1643
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• 2011

본 논문은 적응형 알고리즘(Adaptive Algorithm)을 이용하여 재머(Jammer)를 억제하는 것을 기존의 알고리즘을 시뮬레이션으로 확인한다. 본 논문에서는 원하는 방향으로 빔을 형성하는 동시에 특정방향 주로 부엽(sidelobe)으로 들어오는 재머의 신호를 억제시키는데 있어 여러 가지 적응형 알고리즘을 확인하고, 알고리즘을 이용하여 부엽으로 들어오는 재머신호를 어떻게 억제하는지 시뮬레이션을 통해 결과를 확인하도록 할 것이다.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.7 no.2
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• pp.111-116
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• 2014

In this paper, we estimates the direction of arrival of desired a target using linear array antenna in wireless communication. Direction of arrival estimation is to estimate for desired target position among incident signals on receiver array antennas. This paper improved estimation of direction of arrival for target using optimum weight, high resolution adaptive beamforming algorithm, and sparse matrix for driection of arrival estimation. Through simulation, we showed that we are performance the analysis to compare general algorithm with proposed algorithm. We show that propose algorithm more improve for direction of estimation than general beamforming algorithm.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.3
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• pp.587-592
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• 2018

An adaptive beam forming system using a phased array antenna improves communication quality by beam forming adaptively to a communication environment having an interference signal. For adaptive beam forming, a good combination of the phases of the excited signals to each radiating element of the phased array antenna should be calculated. In this paper, improved particle swarm optimization algorithm that adds a re-spreading procedure according to particle density was proposed to increase the probability of good phase shift combination output.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.12A
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• pp.1214-1222
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• 2006

In this paper, an efficient direction-r)f-arrival based adaptive beamforming algorithm for orthogonal frequency-division multiple-access smart antenna systems is proposed. The proposed algorithm provides a high performance by steering main beams to the directions of a desired signal, whereas steering nulls to the directions of the interference, using the estimated directions. The beamforming outputs obtained by steering the main beams to the distinct directions of resolvable multipath signals are combined in a maximal ratio manner to exploit angular diversity gain. The performance elf the proposed algorithm is finally evaluated in cellular mobile environments to verify its efficiency and is compared with that of least-squares beamforming algorithm, by taking the WiBro system as a target system.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.4C
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• pp.336-341
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• 2008

In this paper, beamforming algorithm is proposed which can obtain diversity gain in beamforming system that deploy antenna elements with half-wavelength. The proposed algorithm provides beam-pattern using eigen-vectors that span received signal subspace. The criterion to decide optimal rank of eigen-space used for beamforming is also proposed. A beamforming system applied the proposed algorithm shows better performance with diversity gain as getting larger angle spread. This paper provides a description of proposed algorithm with analysis of the performance using various computer simulations.

• Journal of the Korea Society of Computer and Information
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• v.13 no.5
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• pp.111-116
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• 2008

Radar system must estimate exactly quickness and target in interference channel. Because interference of radio channel is multipath channel by artificial structure and nature structure. signal estimation is difficult. As long as, get rid of interference signal have been study digital beamforming, adaptive array antenna and so on. In this paper, proposed SPT-SALCMV beamforming algorithm get rid of coherent interference algorithm and adaptive array antenna. Adaptive array forms null pattern and reduces gains for direction of interference signal. And estimate signal that want by keeping gains of beam pattern changelessly to target signal direction. In this paper, proposed SPT-SALCMV algorithm was exactly received position of target. But general SPT-LCMV algorithm resulted beam error about 30degrees. Therefore, proved that SPT-SALCMV algerian that propose in this paper is more excellent than genaral SPT-LCMV algorithm.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.361-364
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• 2001

지금까지 수중음향 시스템에서 jammer 신호를 제거하는 방법에 관한 많은 연구가 진행되어 왔다. 그러나, 기존의 빔형성 기법은 간섭 신호원(interference source)이 움직일 경우 그 성능이 현저히 떨어지는 문제점을 갖고 있다. 이러한 현상은 수중 음향 시스템이 간섭 신호원의 움직임에 대하여 즉각적으로 null의 위치를 변화시키지 못하기 때문에 발생하게 된다. 이를 해결하기 위해서는 시간에 따라 위치가 변하는 jammer 환경에 대하여 대응할 수 있는 새로운 알고리즘이 필요하게 된다. 이러한 단점을 보완하기 위해 본 논문에서는 가변 망각인자를 갖는 적응 빔형성 기법을 제안하고, 컴퓨터 모의실험을 통하여 제안된 알고리즘이 기존의 적응 빔형성 기법에 비하여 출력 SINR(signal to interference plus noise ratio)의 측면에서 성능 향상을 가짐을 보였다.