Solvang, CA, United States

Pacific Advanced Technology

www.patinc.com
Solvang, CA, United States

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Chieh J.-C.S.,Pacific Advanced Technology | Rowland J.,Pacific Advanced Technology
European Microwave Week 2016: "Microwaves Everywhere", EuMW 2016 - Conference Proceedings; 46th European Microwave Conference, EuMC 2016 | Year: 2016

This paper presents a fully tunable reflectionless bandstop filter using multi-section L-Resonators. The bandstop filter is designed to operate in the C-Band, tunable from 3.96 - 4.4 GHz with greater than 20 dB of in-band rejection and a return loss of better than 8 dB across the full tuning range. Simulation and measurement results are presented. © 2016 EuMA.


Zhou X.,Zhejiang University of Technology | Li Y.,City University of Hong Kong | He B.,Fuzhou University | Bai T.,Pacific Advanced Technology
IEEE Transactions on Industrial Informatics | Year: 2014

Tracking multiple moving targets in a video is a challenge because of several factors, including noisy video data, varying number of targets, and mutual occlusion problems. The Gaussian mixture probability hypothesis density (GM-PHD) filter, which aims to recursively propagate the intensity associated with the multi-target posterior density, can overcome the difficulty caused by the data association. This paper develops a multi-target visual tracking system that combines the GM-PHD filter with object detection. First, a new birth intensity estimation algorithm based on entropy distribution and coverage rate is proposed to automatically and accurately track the newborn targets in a noisy video. Then, a robust game-theoretical mutual occlusion handling algorithm with an improved spatial color appearance model is proposed to effectively track the targets in mutual occlusion. The spatial color appearance model is improved by incorporating interferences of other targets within the occlusion region. Finally, the experiments conducted on publicly available videos demonstrate the good performance of the proposed visual tracking system. © 2012 IEEE.


Arceo D.,Pacific Advanced Technology | Arceo D.,Arizona State University | Balanis C.A.,Arizona State University
IEEE Antennas and Wireless Propagation Letters | Year: 2012

The proposed multiport impedance-matching feed network simultaneously optimizes the operating bandwidth and gain of a two-element superdirective antenna array. Maximum directivity of an $N$-element isotropic radiator approaches N2 as the element spacing approaches zero. Additionally, the operating bandwidth of superdirective antenna arrays is narrowband. Utilizing a multiport impedance-matching network will increase the operating bandwidth. Special consideration is required in designing the circuit so that the losses introduced by the matching network do not significantly degrade the absolute gain of the antenna array. © 2002-2011 IEEE.


Arceo D.,Pacific Advanced Technology | Arceo D.,Arizona State University | Balanis C.A.,Arizona State University
IEEE Antennas and Wireless Propagation Letters | Year: 2011

A three-element compact Yagi-Uda antenna is proposed that maintains a high absolute gain and low VSWR over a 10% fractional bandwidth with an element spacing of 0.053λ. The proposed Yagi-Uda antenna uses a director and reflector to create a dual resonance and approach superdirectivity at each resonant frequency. By adjusting the reflector and director's resonant frequency, the gain and bandwidth of the antenna can be maximized. The driven element has one folded arm to increase the impedance of the antenna. The reflector and director elements are bowtie designs to increase the bandwidth. The measured impedance and gain agrees well with the computational model. © 2011 IEEE.


Bres C.-S.,University of California at San Diego | Zlatanovic S.,University of California at San Diego | Wiberg A.O.J.,University of California at San Diego | Adleman J.R.,Pacific Advanced Technology | And 4 more authors.
IEEE Photonics Technology Letters | Year: 2011

A new class of photonic channelized radio-frequency (RF) receiver is proposed and demonstrated. The new device relies on generation of high fidelity signal copies by wavelength multicasting in a self-seeded, two-pump pametric mixer. Signal copying to widely spaced wavelengths enables channelization of the full RF bandwidth using a single periodic filter. The channelization uses freely tunable frequencies of newly generated copies and eliminates the need for construction of a dense, nrowband filter bank. The new concept is demonstrated by channelization of four subcrier channels with 1-GHz spacing and greater than 20-dB extinction ratio between extracted channels. © 2006 IEEE.


Hinnrichs M.,Pacific Advanced Technology
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2011

Recent advances in micro-optical element fabrication using gray scale technology have opened up the opportunity to create simultaneous multi-spectral imaging with fine structure diffractive lenses. This paper will discuss an approach that uses diffractive optical lenses configured in an array (lenslet array) and placed in close proximity to the focal plane array which enables a small compact simultaneous multispectral imaging camera[1]. The lenslet array is designed so that all lenslets have a common focal length with each lenslet tuned for a different wavelength. The number of simultaneous spectral images is determined by the number of individually configured lenslets in the array. The number of spectral images can be increased by a factor of 2 when using it with a dual-band focal plane array (MWIR/LWIR) by exploiting multiple diffraction orders. In addition, modulation of the focal length of the lenslet array with piezoelectric actuation will enable spectral bin fill-in allowing additional spectral coverage while giving up simultaneity. Different lenslet array spectral imaging concept designs are presented in this paper along with a unique concept for prefiltering the radiation focused on the detector. This approach to spectral imaging has applications in the detection of chemical agents in both aerosolized form and as a liquid on a surface. It also can be applied to the detection of weaponized biological agent and IED detection in various forms from manufacturing to deployment and post detection during forensic analysis. © 2011 SPIE.


Hinnrichs M.,Pacific Advanced Technology
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2012

Using diffractive micro-lenses configured in an array and placed in close proximity to the focal plane array will enable a small compact simultaneous multispectral imaging camera. This approach can be applied to spectral regions from the ultraviolet (UV) to the long-wave infrared (LWIR). The number of simultaneously imaged spectral bands is determined by the number of individually configured diffractive optical micro-lenses (lenslet) in the array. Each lenslet images at a different wavelength determined by the blaze and set at the time of manufacturing based on application. In addition, modulation of the focal length of the lenslet array with piezoelectric or electro-static actuation will enable spectral band fill-in allowing hyperspectral imaging. Using the lenslet array with dual-band detectors will increase the number of simultaneous spectral images by a factor of two when utilizing multiple diffraction orders. Configurations and concept designs will be presented for detection application for biological/chemical agents, buried IED's and reconnaissance. The simultaneous detection of multiple spectral images in a single frame of data enhances the image processing capability by eliminating temporal differences between colors and enabling a handheld instrument that is insensitive to motion. © 2012 SPIE.


Grant
Agency: Department of Defense | Branch: Army | Program: SBIR | Phase: Phase I | Award Amount: 148.90K | Year: 2012

This proposal is for a new innovative technology using diffractive optics configured in an array and placed in close proximity to the focal plane array enabling a miniature hyper-spectral LWIR imaging system. Using the right spectral region for detection and analysis of the spectral properties of chemical and biological warfare agents can support efforts to rapidly identify these threats in the battle field. The proposed approach uses diffractive optical elements arrange in an array allowing the collection of multi-color images simultaneously each frame of the multi-spectral/hyper-spectral camera and the entire hyper-spectral data cubes is collected in less than a second. This sensor is applicable to be used by either a dismount, ground based vehicle or airborne platform. Phase I will focus on the conceptual design for a hyper-spectral imaging sensor using lenslets arrays.


Grant
Agency: Department of Defense | Branch: Army | Program: SBIR | Phase: Phase I | Award Amount: 99.31K | Year: 2012

There is a serious need for miniaturized hyperspectral imaging systems that can be used by the soldier in man portable, flown on small Unmanned Arial Vehicles (UAV) or ground robotic instrument (Unmanned Ground Vehicles UGV) applications. Applications include the detection and warning of chemical and biological warfare agents in various forms of threat scenarios from manufacturing to implementation, buried IED"s or forensic analysis of detonated IED"s as well as the detection of IED manufacturing process and plants. Pacific Advanced Technology will develop a MEMS (micro electro mechanical systems) based Fabry-Perot infrared tunable filter to meet the requirements above. We are proposing to use a Fabry-Perot tunable infrared filter that can be programmed to select the spectral bands of interest for the various applications. Phase I will focus on the conceptual design and processing and material constraints on the fabrication of a MEMS based Fabry-Perot infrared tunable filter.


Grant
Agency: Department of Defense | Branch: Army | Program: SBIR | Phase: Phase II | Award Amount: 651.43K | Year: 2013

A miniature (5 pounds, 10 watts) LWIR multi-spectral/hyperspectral imaging system will be developed for applications in remote detection and identification of chemical and biological warfare agents, toxic industrial chemicals (TICs), homemade explosives (HMEs) and disturbed soil indicating a buried IED. This small size and power will allow a handheld instrument that can be carried by a dismount or flown on small UAVs. The uniqueness and innovation of this development effort is not only the small size and low power but the addition of simultaneously imaging in 16 different spectral bands each frame of the camera. Simultaneous multi-spectral and rapid collection of hyperspectral image data can be achieved by taking advantage of the state-of-the-art in micro-optic electro machined systems (MOEMS) technology. Utilizing MOEMS technology circular blazed grating lenslet placed inside the dewar and close to the focal plan array are now possible and give the simultaneous multispectral imaging. An additional advantage to this approach is the inherit cooling of the optics which will minimizes the self-radiation of the lenses and maximize sensitivity.

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