• 한국통신학회논문지
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• 제21권3호
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• pp.763-770
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• 1996

In this paper, the Single-stage Transmission type Injectiong-Locked Oscillator(STILO) was designed and fabicated for the Active Integrated Phased Array Antenna(AIPAA) system. The STILO, which was designed and fabricated by injection-locked technique and hair-pin resonator, has the same 210MHz frequency tuning range of the Voltage Controlled Oscillator(VCO) used by varactor. The locking bandwidth of STILO with 11.5MHz bandwidth, is much better than that of the Injection-Locked Dielectric Resonator Oscillator(ILDRO), And the STILO has the improved noise characteristics in AM, FM, and PM. This STILO is useful for the AIPAA, the coupled VCO array, an the MMIC structure.

• 한국통신학회논문지
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• 제22권8호
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• pp.1622-1631
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• 1997

A 3-stages Active Microstrip Phased Array Antenn(AMPAA) is implemented using Injection-Locking Coupled Oscillators(ILCO). The AMPAA is a beam scanning active antenna with capability of electrical scanning by frequency varation of ILCO. The synchronization of resonance frequencies in array elements is occured by ILCO, and the ILCO amplifies the injection signal and functions as a phase shifter. The microstrip ptch is operated as a radiation element. The unilateral amplifier is a mutual coupling element of AMPAA, eliminates the reverse locking signal and controls the locking bandwidth of ILCO. The possibility of Monolithic Microwave Integrated Circuits(MMIC) of T/R module is proposed by simplified and integrated fabrication process of AMPAA. The 0.75.$lambda_{0}$ is fixed for a mutual coupling space to wide the scanning angle and minimize the multi-mode. The AMPAA has beam scanning angle of 31.4.deg., HPBW(Half Power Beam Widths) of 26.deg., directive gain of 13.64dB and side lobe of -16.5dB were measured, respectively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1511_1512
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• 2009

This paper presents a polarization switching antenna integrated with silicon RF MEMS SPDT switches in the form of a package. A low-loss quartz substrate made of SoQ (silicon-on-quartz) bonding is used as a dielectric material of the patch antenna, as well as a packaging lid substrate of RF MEMS switches. The packaging/antenna substrate is bonded with the bottom substrate including feeding lines and RF MEMS switches by BCB adhesive bonding, and RF energy is transmitted from signal lines to antenna by slot coupling. Through this approach, fabrication complexity and degradation of RF performances of the antenna due to the parasitic effects, which are all caused from the packaging methods, can be reduced. This structure is expected to be used as a platform for reconfigurable antennas with RF MEMS tunable components. A linear polarization switching antenna operating at 19 GHz is manufactured based on the proposed method, and the fabrication process is carefully described. The s-parameters of the fabricated antenna at each state are measured to evaluate the antenna performance.

• ETRI Journal
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• 제27권6호
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• pp.788-797
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• 2005

This paper describes the design and realization of an extra high frequency band $8{\times}8$ microstrip Butler matrix. Operation at 36 GHz is achieved with a frequency bandwidth exceeding 400 MHz. The circuit is implemented on a bi-layer microstrip structure using conventional manufacturing processes. This planar implementation of a Butler matrix is a key component of a switched beam smart antenna with printed antenna elements integrated on-board. Conception details, simulation results, and measurements are also given for the components (hybrid couplers, cross-couplers, and vertical inter-connections) used to implement the matrix.

• 한국정보통신학회논문지
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• 제20권12호
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• pp.2199-2205
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• 2016

본 논문에서는 코플래너 도파관으로 급전되는 소형 2-소자 준-야기 안테나 설계 방법에 대해 연구하였다. 평면 다이폴을 급전하기 위한 코플래너 스트립과 코플래너 도파관 간의 밸런은 코플래너 도파관의 한 쪽 접지 스트립을 신호선과 연결시켜서 구성하였다. 스트립 다이폴과 반사기를 구부리고 밸런을 안테나에 내장하여 소형화하였다. 제안된 구조를 UHF RFID 대역(902-928 MHz)에 적합하도록 설계하였으며, 여러 가지 파라미터들(다이폴 길이, 반사기 길이, 다이폴과 반사기 사이의 거리, 급전 위치 등)에 의한 영향을 점검하였다. FR4 기판 상에 $90mm{\times}80mm$ 크기의 안테나를 제작하고 특성을 실험한 결과 전압 정재파비가 2이하인 주파수 대역은 885-942 MHz, RFID용 주파수 대역 내 이득은 4.3 dBi 이상, 전후방비 7 dB 이상인 특성을 관찰할 수 있었다.

• 대한전자공학회논문지TC
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• 제44권3호
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• pp.105-110
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• 2007

광학계 렌즈이론을 바탕으로 밀리미터파를 집속 시킬 수 있는 렌즈를 설계 제작하고, 이를 이용하여 밀리미터파를 집속하였다. 밀리미터파가 집속되는 초점에 안테나를 위치시키고, 안테나를 기계적으로 이동 시키면서 한점씩의 영상 화소를 취해 전체적인 영상을 얻는 밀리미터파 수동 이미징 시스템을 제작하였다 이를 기반으로 렌즈의 초점면에 2차원적인 안테나 배열이 가능한 영상시스템을 목표로 하여 안테나 배열 소자를 설계 제작하였다. 안테나는 페르미 테이퍼 슬롯 안테나(Fermi Taper Slot Antenna)를 채택하였으며, 이 안테나는 높은 이득과 낮은 부엽 특성를 갖는다. 안테나 배열소자는 안테나, 발룬(Balun), MMIC, 검파기를 하나의 기판위에 집적하여 저손실 및 저잡음 효과를 얻을 수 있을 수 있도록 설계 제작하였다. 집적화된 수동형 안테나 배열 소자는 $4\times1$형태로 제작되었다.

• 한국전자통신학회논문지
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• 제6권5호
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• pp.629-636
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• 2011

본 논문은 차량에 적용하기 위해 통합된 T-DMB/GPS/Mobile 안테나를 설계 제작하였다. T-DMB 안테나는 선형편파와 전 방향 방사패턴을 갖도록 하기 위해 변형된 미앤더 형태의 마이크로스트립 패치를 사용하여 설계하였다. GPS 안테나는 원형편파와 전 방향성 방사패턴을 갖도록 하기 위해 패치 안테나에 슬롯을 삽입하여 설계되었다. 또한 모바일 안테나는 여러 가지 휴대 단말기 주파수 대역인 GSM (880~960 MHz), AMPS (824~894 MHz), DCS (1710~1880 MHz), PCS (1850~1990 MHz), UMTS (1920~2170 MHz) 등에서 동작될 수 있도록 변형된 G 형태의 패치 안테나를 사용하여 설계되었다. 측정결과, VSWR 1:2.5에서 만족하는 임피던스 대역폭은 시뮬레이션 결과와 비슷한 경향을 나타내었다. 또한 2D 그리고 3D 방사패턴과 이득에 측정결과가 제시되고 논의되었다.

• Journal of electromagnetic engineering and science
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• 제5권3호
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• pp.140-145
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• 2005

In this paper, an experimental investigation for return loss and a software-based prediction for interference level of single-packaged filtering antenna composed of dielectric waveguide filter and PCB(Printed Circuit Board) slot antenna in transceiver module have been carried out with several different feeding structures in millimeter-wave regime. The implementation and embedding method of the existing air-filled waveguide filters working at millimeter-wave frequency on general PCB substrate have been described. In a view of the implementation of each components, the dielectric waveguide embedded in PCB and LTCC(Low Temparature Co-fired Ceramic) substrates has employed the via fences as a replacement with side walls and common ground plane to prevent energy leakage. The characteristics of several prototypes of filtering antenna embedded in PCB substrate are considered by comparing the wideband and transmission characteristics as a function of bent angle of transmission line connecting two components. In addition, as an essential to the packaging of transceiver module working at millimeter-wave, miniaturization technology maintaining the performances of independent components and the important problems caused by integrating and connecting the different components in different layers are described in this paper.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권6호
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• pp.286-292
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• 2005

Terahertz wave is a kind of electromagnetic radiation whose frequency lies in 0.1THz $\~$10THz range. In this paper, generation and detection characteristics of terahertz (THz) radiation by photoconductive antenna (PCA) method has been described. Using modern integrated circuit techniques, micron-sized dipole antenna has been fabricated on a low-temperature grown GaAs (LT-GaAs) wafer. A mode-locked Ti:Sapphire femtosecond laser beam is guided and focused onto photoconductive antennas (emitter and detector) to generate and measure THz pulses. Ultra-wide band THz radiation with frequencies between 0.1 THz and 3 THz was observed. Terahertz field amplitude variation with antenna bias voltage, pump laser power, pump laser wavelength and probe laser power was investigated. As a primary application example. a live clover leaf was imaged with the terahertz radiation.

• ETRI Journal
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• 제36권6호
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• pp.881-888
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• 2014

This paper studies the magnetic coupling between two adjacent loop antennas that are parallel to each other in a plane and presents a new practical method to avoid the resulting magnetic coupling interference. The study focuses on the high frequency radio-frequency identification (RFID) system for casino applications, where several loop antennas are closely built into a game table to monitor gaming chips. In this case, neighboring loop antennas may severely interfere with each other by magnetic coupling, which leads to the malfunction of the RFID system. In this paper, we present a practical loop antenna with a new loop switch circuit for avoiding magnetic coupling. The loop switch circuit is integrated with a matching circuit and automatically operated by using an interrogating signal from a reader. We verified the validity of the proposed design by showing that an RFID reader with the proposed antenna can exactly and separately read the gaming chips placed on the different betting zones of a game table.