Planar Active Array Research Articles

Scalable Planar Active Array Antenna Integrated With Distributed Amplifying Transistors for High-Power Applications

A scalable planar 2-D active array antenna configuration that can realize amplified radiation through co-existing active devices is proposed, studied, and demonstrated in this work. The input and output of these amplifying active devices are directly integrated with the feed network and array elements, respectively, thereby eliminating the matching networks typically required in an amplifier circuit. A comprehensive analysis of the rectangular patch antenna (RPA) performance with different feeding techniques is initially analyzed and the choice of nonradiating edge feed RPA as array elements is justified for not only realizing the maximum radiation efficiency but also facilitating the direct active device integration. Subsequently, a physical arrangement of these array elements is devised to reduce cross-polarization. The design of 4×2 active array antenna unit cell operating at 5.8 GHz is then discussed through extensive analysis of active devices, optimization procedure, potential excitation signal control, and influence of faulty transistors. From simulations, this active array scheme has realized a higher matching bandwidth and exhibited an amplifier gain of around 13.6 dB, compared with its passive counterpart. Eventually, these unit cells are integrated through an equal power hybrid feed network for realizing an 8×8 active array antenna configuration that is fabricated and measured. The measured results of the experimental prototype match reasonably well with the simulation results, thereby confirming the proposed integration technique. The resulting paralleled configuration promises efficient handling of greater powers, making them suitable for high-power applications.

전자전용 광대역 평면형 능동위상배열 안테나 시스템 개발

전자전용 광대역 평면형 능동위상배열 안테나 시스템 개발

부배열 합성을 이용한 적응적 빔형성기의 구현 및 성능 분석

In this paper, we present the performance and the experimental results of the adaptive beamformer in the radar system with the planar active array. The study of the adaptive beamformer has already been performed in several literatures, but it is difficult to find the results or examples those are implemented in the actual radar system. Here we employ the adaptive beamformer to the practical radar system with subarray architecture. The performance of beamformer will be demonstrated by modeling and simulation and finally the far-field experimental results.

TLM modelling of multilayer coupling structures for microwave PCS antennas

This paper presents a multilayer architecture applicable to integrated planar active array antennas in personal communication systems (PCSs). The configuration uses a combination of microstrip and stripline transmission lines on stacked substrates to integrate printed patch antennas, microwave active circuits, signal-distribution networks, etc., into a compact multilayer system. A general-purpose EM simulator based on the transmission-line matrix (TLM) has been developed to model some vertical interconnections in a multilayer construction. Good agreement is obtained between measurements and numerical results of a monolithic microwave integrated circuit (MMIC) via hole, a novel broadband stripline coupler, and an aperture-coupled dielectric resonator antenna.

A self-steering planar array antenna for satellite broadcast reception

The active planar array antenna offers a number of advantages, including use as a portable antenna for easy reception of direct Ku-band satellite television broadcasts. This paper presents a newly developed active planar array antenna which provides electronic beam-tracking without mechanical tracking equipment. The features of the antenna are: (1) use of a series-parallel fed microstrip array, (2) electromagnetically excited array by a coplanar patch connected to the coplanar waveguide, and (3) low noise down-converters and self-phasing units incorporated into the feed circuits for electronic beam-tracking. The paper discusses the design of the coplanar waveguide fed coplanar patch and the configuration of a self-phasing active planar array antenna. The measured gain of the experimental 9-element unit array antenna without active devices is 13.4 dBi at 11.85 GHz. Experimental results for a 216-element self-steering planar array of size 147/spl times/220.5 mm are also presented.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Active inverted stripline circular patch antennas for spatial power combining

An active antenna configuration is proposed for spatial-power-combining applications. The active patch antenna uses an inverted stripline topology to take advantage of several features. These features include avoiding drilling through the circuit substrate to insert the diode and the use of air within the resonant cavity to reduce loss. The inverted substrate serves as a radome for hermetic sealing. The active antenna and housing can be fabricated in modular form for reduced cost and easy replaceability of devices. The active inverted stripline patch antenna exhibits a much cleaner spectrum and greater stability than previously reported active antennas. The fixture serves as a ground plane, heat sink, and support in an active planar array or as a mirror in a quasi-optical power-combining resonator. A single active antenna operating at 9.23 GHz exhibited a 16-MHz locking bandwidth at 30-dB locking gain. Power-combining efficiencies of over 89% have been demonstrated for a four-element square array that maintained injection-locking and power-combining over a 60-MHz bias tuned bandwidth. Similarly, a four-element diamond array showed over 86% combining efficiency and 50-MHz bias tuned bandwidth. Beam steering was demonstrated by varying bias voltage to the individual antenna elements of the square array.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>