A planar array antenna fed by waveguide parallel feed circuits is presented. It is constructed with a sub-array with four apertures fed by the waveguide. This antenna has characteristics of high aperture efficiency and broad frequency bandwidth.

Cited by 1

Planar CMOS/SOS Array Development.

C.E. Weitzel · Defense Technical Information Center (DTIC) · 1976

Three techniques for planarizing silicon-on-sapphire epitaxial islands are investigated. These three approaches are thermal oxidation isolation, ion-implantation isolation, and SIS (silicon-in-sapphire). N-channel MOS transistors fabricated using thermal oxidation isolation exhibit large edge leakage currents and are bias-temperature unstable. Stable p-channel MOS transistors can be fabricated if the field oxide is grown below 950 C in HCl steam. Test transistors fabricated using ion-implantation isolation show very large edge leakage current.

Cited by 1

Steered planar nearfield calibration array

A. L. Van Buren · The Journal of the Acoustical Society of America · 1978

The Trott planar nearfield calibration array (NFCA) is a two-dimensional array of small, reciprocal hydrophones whose responses are shaded to produce a nearly uniform plane wave throughout a volume in the nearfield of the array. When a transducer to be calibrated is placed in the plane-wave volume, the signal received by the NFCA is proportional to the farfield pressure radiatied by the transducer in the direction opposite to the plane wave. Previous NFCA’s were shaded so that the plane-wave direction was normal to the array. It was necessary to rotate the transducer in order to obtain the farfield pressure distribution. In the present study we obtain shading coefficients that allow the nearfield plane wave to be steered to angles up to 70° from the normal to the array. These coefficients allow the determination of a 140° sector of the azimuthal farfield pattern without rotating the transducer. We experimentally verified the shading coefficients by successfully calibrating a large piston transducer. Here we synthesized the steered planar NFCA by combining responses of a single line of shaded hydrophones to form a virtual NFCA. The synthetic aperture technique allows the calibration of large sound sources without having to build the entire NFCA.

Cited by 5

Extendible Planar Phased Array Mast

Sirmalis, John E · Defense Technical Information Center (DTIC) · 1999

The invention provides a hydrodynamically and stealth shaped suite of antennas and sensors mounted above a hydrodynamically and stealth shaped mast. The mast is configured to extend from the sail of a submerged vessel to the surface so as to provide the vessel with satellite communications capabilities. The hydrodynamic shape of the mast minimizes the surface wake and the stealth shape of the antenna suite and mast minimizes the radar cross section of the system, lessening detection by hostile forces. To obtain a stealth shape, the radar suite utilizes a conformal phased array antenna. In addition, electro-optical sensors in the antenna suite provide visual, environmental and other sensing capabilities to the system. Further, structurally embedded ESM antennas provide ESM and radar capabilities. When in the retracted position, the antenna system conforms to the hydrodynamic and stealth shape of the submerged vessel and the conformal phased array of the antenna suite forms an integral part of the conformal phased array of the vessel.

Cited by 0

Planar solid state laser array

COMERFORD, LIAM DAVID, ZORY, JR., PETER STEPHEN · Institutional Repository of Xi'an Institute of Optics and Fine Mechanics, Chinese Academy of Sciences (Xian Institute of Optics and Precision Mechanics) · 1977

An array of collimated wise aperture electrically pumped leaky corrugated AlGaAs optical waveguide lasers is formed on a single chip by etching a series of grooves oriented with respect to the crystalographic planes to isolate discrete lasers in the array and provide the requisite orientation of the internal reflecting surfaces to support the lasing action. The corrugation period is chosen such that the laser radiation exits from the array in a direction normal to the plane of waveguide.

Cited by 0

Polarization‐independent planar amplifier array

Ashley Robinson, M.E. Bialkowski · Microwave and Optical Technology Letters · 1999

Cited by 5

PLANAR LEAKY -MODE ANTENNA ARRAY

Tsai-Pi Hung, Ching-Kuang C. Tzuang · 2001

mechanism of the single element, by exciting the first higher order mode (EH mode), can be estimated by the full-wave analysis. Through appropriately arranging and feeding these 192 single elements, the radiated characteristic of the antenna performs narrow radiation beamwidth both in azimuth (AZ) and elevation (EL), thus achieving high directivity. The planar microstrip antenna array prototype is built and tested at 38GHz by traditional printed circuit board (PCB) fabri cating process. The measurement result indicates the high dir ecti vity of22.3dB and the 3-dB beamwidth of 8°112° (AZlEL) at the elevated angle 30.2° away from the broadside direction.

Cited by 0

Planar microstrip YAGI antenna array

Huang, John · NASA Technical Reports Server (NASA)

A directional microstrip antenna includes a driven patch surrounded by an isolated reflector and one or more coplanar directors, all separated from a ground plane on the order of 0.1 wavelength or less to provide end fire beam directivity without requiring power dividers or phase shifters. The antenna may be driven at a feed point a distance from the center of the driven patch in accordance with conventional microstrip antenna design practices for H-plane coupled or horizontally polarized signals. The feed point for E-plane coupled or vertically polarized signals is at a greater distance from the center than the first distance. This feed point is also used for one of the feed signals for circularly polarized signals. The phase shift between signals applied to feed points for circularly polarized signals must be greater than the conventionally required 90 degrees and depends upon the antenna configuration.

Cited by 0

Planar strip array (PSA) for MRI

Ray F. Lee, Charles R. Westgate, Robert G. Weiss et al. · Magnetic Resonance in Medicine · 2001

Parallel, spatial-encoded MRI requires a large number of independent detectors that simultaneously acquire signals. The loop structure and mutual coupling in conventional phased arrays limit the number of coils and therefore the potential reduction in minimum scan time achievable by parallel MRI tchniques. A new near-field MRI detector array, the planar strip array (PSA), is presented that eliminates the coupling problems and can be extended to a very large number of detectors and high MRI frequencies. Its basic structure is an array of parallel microstrips with a high permittivity substrate and overlay. The electromagnetic (EM) wavelength can be adjusted with the permittivity, and the strip lengths tuned to a preselected fraction of the wavelength of the MRI frequency. EM wave analysis and measurements on a prototype four-element PSA reveal that the coupling between the strips vanishes when the strip length is either an integer times a quarter wavelength for a standing-wave PSA, or a half wavelength for a travelling-wave PSA, independent of the spacing between the strips. The analysis, as well as phantom and human MRI experiments performed by conventional and parallel-encoded MRI with the PSA at 1.5 T, show that the decoupled strips produce a relatively high-quality factor and signal-to-noise ratio, provided that the strips are properly terminated, tuned, and matched or coupled to the preamplifiers. Magn Reson Med 45:673-683, 2001.

Cited by 81Open access

Broadband meander line planar array antenna

G.A. Hockham, R. Wolfson · 2005

Cited by 1

Planar Antenna Array For Ku Band

Prouza, Jakub · Brno University of Technology Digital Library (Brno University of Technology) · 2019

The paper deals with the design of an antenna element of an ultra-wideband antenna array for specialized applications. The realized gain of the whole structure, the main beam width and the possibility of electronic beamforming in the horizontal plane are the most important parameters of the designed antenna array. The numerical model of the antenna array is created, and parameters are verified to prove suitability for ultra-wideband applications.

Cited by 0Open access

Planar Directivity of a Dipole Array

Jiaruo Yan, E. Shamonina, C.J. Stevens · 2018 12th International Congress on Artificial Materials for Novel Wave Phenomena (Metamaterials) · 2018

We develop a technique for fast evaluation of superdirective performance of coupled meta-atoms. Traditionally, the directivity of a small antenna is obtained from measurements of the far-field radiated power over a spherical surface. We propose an alternative method of finding the directivity from a faster polar scan over a circular path, by introducing the "planar directivity" (D 2D ) for dipole arrays. We derive analytical expressions for maximum achievable values of directivity and D 2D , establish the correlation between them, and identify the range of parameters (inter-element distance, coupling constant, quality factor) for which the conversion of D 2D to D for superdirective dimers is possible.

Cited by 0

Non-Planar Aperture MIMO Array Imaging

Shiyong Li, Guoqiang Zhao, Houjun Sun · 2023

Millimeter-wave (MMW) imaging holds great promise for concealed weapons detection. To reduce system costs, the multiple-input multiple output (MIMO) array has been extensively adopted for MMW imaging. Additionally, employing a fully electronic MIMO array is anticipated to facilitate realtime imaging, which holds significant prospect in the scenario of high-throughput safety checks. This paper provides a review of non-planar aperture MIMO array-based imaging, which offers a broader range of viewing and detection angles for the human body compared to systems using planar apertures.

Cited by 0

Ultrasound Planar Array Imaging Metric Analysis

Cuijuan Lou, Feng Xiao, Junjie Song et al. · IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control · 2021

Planar array design makes the tradeoff between the 3-D ultrasound image quality and the system complexity based on the imaging metrics. The -6 dB mainlobe width (MW), mainlobe-to-sidelobe energy ratio (MSR), peak sidelobe level (PSL), and average sidelobe level (ASL) are the common imaging metrics for linear array design. MW is used for lateral resolution evaluation, while MSR, PSL, and ASL are adopted for contrast resolution evaluation. However, simulation results show that these metrics cannot fully evaluate the planar array performance. This article proposes several new imaging metrics for planar array: averaged mainlobe acoustic energy level and mainlobe energy density curve are the lateral resolution metrics, while mainlobe-to-sidelobe energy density ratio is the contrast resolution metric. The new metrics take into account the influence of the mainlobe area on the planar array performance evaluation. PSF analysis and simulated images show that the proposed metrics can evaluate planar array performance more accurately than the existing metrics. Moreover, uniform planar arrays with different scales and random sparse arrays are tested to show how to use the proposed metrics in planar array design.

Cited by 2

Series-fed planar dipole array antenna

Matthew Straughn, Chi‐Chih Chen · 2017

A planar dipole array antenna operating around 2.4 GHz is presented. The array has five dipole elements that are excited in phase to reduce the elevation beamwidth for reducing undesired multipath signals and increase gain. The array is fed from the bottom with a single coaxial connector which sequentially excites all array elements in phase via a twin wire transmission line. The antenna is just 8mm wide and 1.27mm thick.

Cited by 6

Millimetre-wave Planar Bruce Array Antenna

Zeeshan Ahmed, Ha Hoang, Patrick McEvoy et al. · Arrow - TU Dublin (Technological University Dublin) · 2020

A tri-band mm-wave planar Bruce array antenna for fifth generation communications (5G) is presented. The 16-element planar Bruce array antenna is simulated and fabricated on Rogers RT/Duroid 5880 substrate with thickness of 0.254 mm. For a compact and simple structure, the antenna has a highly directional fan-beam radiation pattern at broadside and peak realized gain of 14.0 dBi.

Cited by 5Open access