• Title/Summary/Keyword: Beam forming

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Analysis of DOA Estimation and Adaptive Beam-forming of MIMO between Linear-circular Array Antennas (선형-원형배열 안테나에 따른 MIMO의 DOA 추정과 적응 빔성형 분석)

  • Yang, Doo-Yeong;Lee, Min-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.6
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    • pp.2777-2784
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    • 2011
  • In this paper, DOA(direction of arrival) of multiple incident signals received from linear array antenna and circular array antenna, which is based on nonparametric estimation algorithm, and adaptive beam-forming algorithm are studied and analyzed. In nonparametric estimation algorithm, we minimize a regularized objective function for finding a estimate of the signal energy as a function of angle, using nonquadratic norm which leads to supper resolution and noise suppression. And then, DOA is estimated by the signal and noise spatial steering vector, and adaptive beam-forming pattern is improved by weight vectors obtained from the spatial vector. Especially, the discrimination ability of DOA and the adaptive beam-forming ability according to antenna array methods and the number of array elements are compared and considered.

Topology Optimization of Beam Splitter for Multi-Beam Forming Based on the Phase Field Design Method (페이즈 필드 설계법 기반의 다중 빔 형성을 위한 빔 분배기 위상최적설계)

  • Kim, Han-Min
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.32 no.3
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    • pp.141-147
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    • 2019
  • In this paper, a systematic beam splitter design for multi-beam forming is proposed. The objective of this research is to a design beam splitter that splits and focuses scattering microwaves into intense beams in multiple directions. It is difficult to split multi-beam to non-specific directions with theoretical approaches. Therefore, instead of using transformation optics(TO), which is a widely used process for controlling electromagnetic wave propagation, we used a systematic design process called the phase field design method to obtain an optimal topological structure of beam splitter. The objective function is to maximize the norm of electric field of the target areas of each direction. To avoid island structure and obtain the structure in one body, volume constraint is added to the optimization problem by using augmented Lagrangian. Target frequency is set to X-band 10GHz. The optimal beam splitter performed well in multi-beam forming and the transported electric energy of target areas improved. A frequency dependency test was conducted in the X-band to determine effective frequency range.

Design of Flower Pattern in Roll Forming Process for Ultra High Strength Bumper Beam (초고강도 범퍼 빔의 롤 포밍 공정을 위한 플라워 패턴 설계)

  • Cha, T.W.;Kim, J.H.;Kim, G.H.;Kim, B.M.
    • Transactions of Materials Processing
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    • v.25 no.5
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    • pp.319-324
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    • 2016
  • Recently, the roll forming process is one of the most widely used processes for manufacturing automotive part. In this study, flower patterns of roll forming process were designed to manufacture an ultra high strength bumper beam using the finite element analysis. Three types of flower patterns such as the basic type, the rotation type and the split type were designed based on the constant arc length forming method using the design software, UBECO Profil. Finite element analysis was performed to evaluate the suitability of designed flower patterns in terms of the longitudinal strain and the bow defect. The analytical results show that the split type represents more uniform longitudinal strain distributions and a good dimensional accuracy than other types of flower patterns.

A Relative Position Estimation System using Digital Beam Forming and ToA for Automatic Formation Flight of UAV (UAV 자동 편대비행을 위한 디지털 빔포밍 및 ToA 기반의 상대위치 추정 시스템)

  • Kim, Jae-Wan;Yoon, Jun-Yong;Joo, Yang-Ick
    • Journal of Korea Multimedia Society
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    • v.17 no.9
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    • pp.1092-1097
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    • 2014
  • It is difficult to perform automatic formation flight of UAV (Unmanned Aerial vehicle) when GPS (Global Positionig System) is out of order or has a system error, since the relative position estimation in the flight group is impossible in that case. In this paper, we design a relative localization system for the automatic formation flight of UAV. For this purpose, we adopt digital beam forming (DBF) to estimate the angle with the central controller of the flight group and Particle Filtering scheme to compensate the estimation error of ToA (time of arrival) method. Computer simulation results present a proper distance between the central controller and a following unit to maintain the automatic formation flight.

Design of 24 GHz Radar with Subspace-Based Digital Beam Forming for ACC Stop-and-Go System

  • Jeong, Seong-Hee;Oh, Jun-Nam;Lee, Kwae-Hi
    • ETRI Journal
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    • v.32 no.5
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    • pp.827-830
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    • 2010
  • For an adaptive cruise control (ACC) stop-and-go system in automotive applications, three radar sensors are needed because two 24 GHz short range radars are used for object detection in an adjacent lane, and one 77 GHz long-range radar is used for object detection in the center lane. In this letter, we propose a single sensor-based 24 GHz radar with a detection capability of up to 150 m and ${\pm}30^{\circ}$ for an ACC stop-and-go system. The developed radar is highly integrated with a high gain patch antenna, four channel receivers with GaAs RF ICs, and back-end processing board with subspace based digital beam forming algorithm.

Automotive Cruise Control (ACC) Radar Application of Digital Beam Forming Technique (Digital Beam Forming 기술의 차량 충돌 방지용 레이더 응용)

  • Park, Young-Jin;Kim, Kwan-Ho;Lee, Won-Tae;Oh, Hui-Myoung
    • Proceedings of the KIEE Conference
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    • 2003.07c
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    • pp.1949-1951
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    • 2003
  • 본 논문에서는 수신 측에서 Digital Beam Forming 기술을 응용한 새로운 개념의 차량 충돌 방지용 레이더를 소개한다. 이는 기존의 기술보다 더 넓은 범위에서 차량 탐색이 가능하고, 고해상도를 가지면서, 한 측정 단위 셀 내에서 여러 개의 물체를 찾아낼 수 있다. 제안된 방법은 기존 차량충돌 방지용 레이더의 송수신 안테나에 있어서의 많은 제약을 극복할 수 있는 방법이다.

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Proposal and Analysis of the Orthogonal Beam Forming using Reactance Control (리액턴스 제어를 이용한 능동형 빔포밍의 제안 및 분석)

  • Lee, Kyu-Tae;Ki, Jang-Geun
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.5
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    • pp.81-86
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    • 2014
  • A smart phone subscriber needs wide bandwidth services for more fast data communication on the internet. The conventional MIMO system is now developing to resolve these problems with limited device space for antenna and frequency band environment reserved. One of way to make it practically is to add the number of antennas theoretically. But it is difficult to increase the antenna element as a limited space on the system. Therefore an active beam forming scheme is known as a way of constructing a Compact MIMO system for that. In this paper, the fast switching control block was suggested to adjust a reactance of the antenna element and verified experimentally the effects by switching signal on an orthogonal beam forming through a spatial domain.

Polyphase I/Q Network and Active Vector Modulator Based Beam-Forming Receiver For UAV Based Airborne Network (UAV 공중 네트워크를 위한 손실 없는 Polyphase I/Q 네트워크 및 능동 벡터 변조기 기반 빔-포밍 수신기)

  • Jung, Won-jae;Hong, Nam-pyo;Jang, Jong-eun;Chae, Hyung-il;Park, Jun-seok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.41 no.11
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    • pp.1566-1573
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    • 2016
  • This paper presents a beam-forming receiver with polyphase In-phase/Quadrature-phase (I/Q) network for airborne communication. In beam-forming receiver, the insertion loss (IL) difference between input path increases the receiver noise figure (NF). The major element for generating IL difference is the impedance variation of phase shifter. In order to maintain a constant IL in every phase, this paper propose a lossless polyphase I/Q network based beam-forming receiver. The proposed lossless polyphase I/Q network has low Q-factor and high impedance for drive back-end VGA (Variable gain amplifier) block with low insertion loss. The 2-stage VGA controls in-phase and quadrature-phase amplitude level for vector summation. The proposed beam-forming receiver prototype is fabricated in TSMC $0.18{\mu}m$ CMOS process. The prototype cover the $360^{\circ}$ with $5.6^{\circ}$ LSB. The average RMS phase error and amplitude error is approximately $1.6^{\circ}$ and 0.3dB.

Improved Genetic Algorithm for Pattern Synthesis of Phased Array Antenna (위상 배열 안테나의 패턴 합성을 위한 개선된 유전 알고리즘)

  • Jung, Jin-Woo
    • The Journal of the Korea institute of electronic communication sciences
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    • v.13 no.2
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    • pp.299-304
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    • 2018
  • An improved genetic algorithm was proposed for pattern synthesis of an adaptive beam forming system using phased array antennas. The proposed genetic algorithm is an algorithm that adds acquired characteristics procedure to solve local optimization using the diversity. The performance of the proposed genetic algorithm is verified through the problem of finding a suitable chromosome for a picture composed of binary. And it is confirmed that it is suitable for the adaptive beam forming system based on the performance problem of combining main beam and two pattern nulls.

A study on development of simulation model of Underwater Acoustic Imaging (UAI) system with the inclusion of underwater propagation medium and stepped frequency beam-steering acoustic array

  • L.S. Praveen;Govind R. Kadambi;S. Malathi;Preetham Shankpal
    • Ocean Systems Engineering
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    • v.13 no.2
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    • pp.195-224
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    • 2023
  • This paper proposes a method for the acoustic imaging wherein the traditional requirement of the relative movement between the transmitter and target is overcome. This is facilitated through the beamforming acoustic array in the transmitter, in which the target is illuminated by the array at various azimuth and elevation angles without the physical movement of the acoustic array. The concept of beam steering of the acoustic array facilitates the formation of the beam at desired angular positions of azimuth and elevation angles. This paper substantiates that the combination of illumination of the target from different azimuth and elevation angles with respect to the transmitter (through the beam steering of beam forming acoustic array) and the beam steering at multiple frequencies (through SF) results in enhanced reconstruction of images of the target in the underwater scenario. This paper also demonstrates the possibility of reconstruction of the image of a target in underwater without invoking the traditional algorithms of Digital Image Processing (DIP). This paper comprehensively and succinctly presents all the empirical formulae required for modelling the acoustic medium and the target to facilitate the reader with a comprehensive summary document incorporating the various parameters of multi-disciplinary nature.