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ACOUSTOOPTIC CHANNEL EQUALIZATION FOR digital-COMMUNICATIONS 6

ACOUSTOOPTIC CHANNEL EQUALIZATION FOR DIGITAL-COMMUNICATIONS

6TH INTERNATIONAL SYMP AND EXHIBITION ON optical ENGINEERING AND PHOTONICS / 3RD CONF ON optoelectronic signal processing FOR PHASED-ARRAY ANTENNAS

作者： ANDERSON, CS Dynetics Inc. (United States)

ISBN: (纸本)0819408689

digital communication systems use complex modulation schemes that require powerful signal- processing techniques to correct chemical distortions and to minimize bit error rates. In this paper, acousto-optic processors are used, in conjunction with adaptive digital equalizers, to reduce the bit error rate of a microwave digital radio receiver. The acousto-optic processor implements an inverse channel filter that is rapidly adaptable to time varying distortions. A specific architecture is identified and a laboratory system is tested to very the ability of the processor to track and correct time-varying channels. Computer simulations are used to show that the hybrid acousto-optic and digital equalizer allows a four-fold increase in the modulation capacity of radio, relative to all digital equalization, while improving the bit error rate performance.

关键词： Acousto-optics optical filters Modulation Electronic filtering Receivers Mirrors signal processing digital filtering Microwave radiation Data communications

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optical-processing FOR SELF-COHERING OF PHASED-ARRAY IMAGING signalS 6

OPTICAL-PROCESSING FOR SELF-COHERING OF PHASED-ARRAY IMAGING...

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6TH INTERNATIONAL SYMP AND EXHIBITION ON optical ENGINEERING AND PHOTONICS / 3RD CONF ON optoelectronic signal processing FOR PHASED-ARRAY ANTENNAS

作者： WEVERKA, RT WAGNER, K SARTO, AW Univ. of Colorado/Boulder (United States)

ISBN: (纸本)0819408689

We describe three real-time optical processing systems, for imaging radar, that form the array phase function and produce the radar image from the incoming signals. The first is an implementation of the Steinberg algorithm where we have modified the data format by frequency multiplexing the range information to allow for the data from all range bins to be present simultaneously. The second implementation uses this same input format, but provides hysteresis on the point scatterer used to calibrate the array. This allows for moving radar arrays where the point used to calibrate the array may be time varying. Finally we describe a self oscillating phase conjugate resonator, with a coherent optical to RF converter inside the cavity. This is a hybrid optical-microwave oscillator that adapts to the incoming signal.

关键词： Radar Reflectors Bragg cells Phased array optics Antennas Diffraction Oscillators Phase conjugation Phased arrays Calibration

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PHOTOGRAPHIC SCANNER WITH INTEGRATED CHARGE COUPLED DEVICE

PHOTOGRAPHIC SCANNER WITH INTEGRATED CHARGE COUPLED DEVICE

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CONF ON HIGH-RESOLUTION SENSORS AND hybrid systems

作者： BOYD, S BENCUYA, S MCGRATH, D SAYLOR, S SMYTH, W Polaroid Corp. (United States)

ISBN: (纸本)0819408107

A scanner with an integrated 2048-element-per-line color charge-coupled device (CCD) image sensor has been developed for scanning 4" x 6" photographs at up to 500 dots/in resolution. Integration of the three sensors with color filters on a single chip greatly simplifies the scanner system design. The scanner system includes light-source optics mechanical drive CCD drive electronics digital signal processing (DSP) electronics and controlling hardware/firmware. A novel selfcalibration scheme provides brightness and uniformity correction to the scanned image data in real time. Also in real time DSP circuits perform sharpening and color processing allowing for fast high quality scans of photographic images. Prints of up to 4" x 6" are scanned at 500 dots/in resolution and 24-bit color in less than 10 seconds. Application areas include graphic arts technical and scientific imaging insurance and real estate. 1.

关键词： Charge-coupled devices Scanners digital signal processing Imaging systems Photography signal processing Sensors CCD image sensors Computing systems Electronics

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optical-processing ARCHITECTURES FOR MACHINE VISION FUNCTIONS

OPTICAL-PROCESSING ARCHITECTURES FOR MACHINE VISION FUNCTION...

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CONF ON MACHINE VISION ARCHITECTURES, INTEGRATION, AND APPLICATIONS

作者： BRASHER, J HESTER, C KINSER, J SELZER, F TEMMEN, M Teledyne Brown Engineering (United States)

ISBN: (纸本)0819407526

Manufacturers must increase production rates and simultaneously tighten quality/process controls in order to meet ever-increasing competition and consumer demands for high quality products. This requires that products be manufactured more efficiently, at reducing cost, and with minimum scrap/waste. This in turn demands higher-speed inspection, with higher accuracy and consistency as well as intelligence. Achieving these goals will require highly parallel systems that perform image processing and pattern recognition in real time in various manufacturing environments. This paper presents a hybrid architecture combining state-of-the- art optical processing with conventional digital processing. A Solid optical Correlator (SOC) system has been built and validated. The SOC incorporates rigidity, stability, and manufacturability--attributes which facilitate the use of the optical correlator in real-world industrial machine vision applications.

关键词： Machine vision optical signal processing Manufacturing optical correlators System on a chip Control systems digital signal processing image processing Inspection Pattern recognition

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DIRECT VIDEO ACQUISITION BY digital signal PROCESSORS

DIRECT VIDEO ACQUISITION BY DIGITAL SIGNAL PROCESSORS

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CONF ON HIGH-RESOLUTION SENSORS AND hybrid systems

作者： DESA, L SILVA, V SILVESTRE, J Univ. de Coimbra (Portugal)

ISBN: (纸本)0819408107

Almost any frame grabber system has a special controller circuit to transfer data from the video analog to digital converter (ADC) to the system memory. This controller which normally includes a locked phase loop (PLL) and several counters has to fulfill three main functions: the generation of a pixel clock synchronized with the incoming video signal the command of the ADC and memory addressing for the storage of the digitized video. This paper shows how a digital signal processor (DSP) can simplify the design of a video acquisition system by reading the video ADC and writing to its memory at video rates. An example is given with the TM5320C30 processor which supports simultaneous read and write operations on its two external buses. In the case of the CCJR 601 video format the processor runs at 27 MHz. Modern versions of the TMS32OC3O running at as fast as 40 MHz can acquire up to 1066 samples per line. Also the 32-bit wide buses of the processor allows colour acquisition using this technique. In order to build a so simple circuit the DSP needs to be synchronized to the incoming video signal which can be neatly done by using the TMS32OC3O internal timer as part of the PLL. By changing the programming of the internal timer any video format can be grabbed. In addition the DSP can be used as a powerful image

关键词： digital signal processing signal processing Video Clocks image processing Video processing image resolution Sensors Data acquisition Imaging systems

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HDTV CAMERA USING digital CONTOUR

HDTV CAMERA USING DIGITAL CONTOUR

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CONF ON HIGH-RESOLUTION SENSORS AND hybrid systems

作者： SUGIKI, T NAKAO, A UCHIDA, T Toshiba Corporation (Japan)

ISBN: (纸本)0819408107

The authers have developed the HSC-100 solid-state High-Definition TV(Camera. The canra promises a 6dB S/N and +6dB sensilivity far superior to conventional IIDTV cameras due to an imaging device construction. It also improves picture quality throughusing a digital contour unit. To satisfy IiDTV (SMPTE 240M) requirements a photo-conductive layered semiconductor imaging device (PSID) with 2 pixels has been developed. An amorphous silicon (a-Si) layeris added to the CCD scanner in this device. The a-Si layer carries out photoelectric conversion then interline transfer CCD reads out the photo induced electric charges. This configuraon provides a pixel aperture ratio of 100 thereby improving sensitivity comparedwith existing models. The layer structure also permits a wide dynamic range. A digital contour unit was developed to improve contour corrector characteristics. S/N and frequency response are improved by introducing digital signal processing. The 56dB S/N value is achieved with an 8 bit A/D converter. This S/N is about 10 dB better than that for conventional ultra-sonic delay lines. In addilion digital processing improves frequency response and delay time stability. A more natural contour correction characteristic has been attained with a contour correction signal derived from the luminance signal. 1.

关键词： Cameras image sensors Solid state electronics Charge-coupled devices image enhancement Sensors Amorphous silicon Control systems Imaging systems digital cameras

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VERY HIGH-RESOLUTION SCANNER AND image-processing SYSTEM

VERY HIGH-RESOLUTION SCANNER AND IMAGE-PROCESSING SYSTEM

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CONF ON HIGH-RESOLUTION SENSORS AND hybrid systems

作者： GIBBON, DC KOLLARITS, RV AT&T Labs. Research Corp. (United States)

ISBN: (纸本)0819408107

A high-resolution imaging system employing a CCD line scan camera has been constructed with a resolution of 6000 x 6000 x 12 bits per pixel per color component with a variable pixel aspect ratio. The raw image data is processed in real time to correct for one dimensional artifacts arising from the sensor dark current signal as well as gain and integration control nonuniformities. The gain nonuniformity correction includes second order effects. Two dimensional artifacts attributable to sensor window defects are also removed. The system''s noise performance is found to be limited primarily by sensor shot noise and uncorrected sensor nonuniformities. For most images the system noise is below the visible threshold. This still imaging system has been used to digitize color transparencies up to 6 X 6cm including 35 and 70mm motion picture film for HDTV motion test sequences. 1. OVERVIEW AND DESIGN CONSIDERATIONS The CCD line scan camera described in this paper was designed as a laboratory system to be used as a source of high quality image data for visual communications research. A block diagram of the system is shown in Figure 1. The intent was to produce digital images of sufficient resolution and quality to meet the needs of HDTV researchers for the foreseeable future in fact the scanner''s resolution far exceeds that of present display technology. Output image quality was the primary design consideration and attention

关键词： Sensors Scanners image processing image sensors Transparency Analog electronics Charge-coupled devices image resolution Lamps Modulation transfer functions

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hybrid optoelectronic processors generate images in real time

Laser Focus (Littleton, Massachusetts)

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Laser Focus (Littleton, Massachusetts) 1992年第9期28卷 123-132页

作者： Lafuse, James Turpin, Terry Essex Corp Columbia United States

Many image-synthesis problems are computation intensive. An emerging technology that combines optics and digital electronics may provide faster and simpler image processing. A family of hybrid optoelectronic processors, developed and patented by our company, can provide real-time complex image synthesis (see photo). A typical, moderate-capability processor will generate a real-time 512 × 512-pixel image with 80-dB dynamic range in a package roughly equivalent to a desktop PC weighing 30 lb. Using only about 50 W of power, such a system includes an optical-processor module and all support electronics. The processor can extend state-of-the-art imaging techniques such as synthetic-aperture radar (SAR), CAT (computerized axial tomography) scans, magnetic-resonance imaging, microscopy, and acoustic imaging beyond current technological limits. The technology will enable real-time image processing at speeds that exceed video rates and will enable three-dimensional (3-D) processing for some imaging modes. The inherent simplicity of the processor makes possible the manufacture of inexpensive and reliable optical systems for imaging applications ranging from airborne reconnaissance to medical ultrasound applications.

关键词： image processing

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HIGH-PERFORMANCE, DUAL SPEED, MULTIPORT CCD CAMERA

HIGH-PERFORMANCE, DUAL SPEED, MULTIPORT CCD CAMERA

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CONF ON HIGH-RESOLUTION SENSORS AND hybrid systems

作者： DOHERTY, PE SUTCLIFFE, P SIMS, GR Photometrics Ltd./Advanced Technologies Div. (United States)

ISBN: (纸本)0819408107

The AIS2 is a dual speed multi-port slow-scan CCD imaging system intended for use in applications which require both low speed low noise operation and higher speed setup and acquisition modes. Flexibility in CCD operation is emphasized and all CCD control voltage and timing may be reconfigured through software command. Additionally multi-port CCDs and multi-device CCD mosaics may be supported with separate clock voltage references and timing generators for each CCD or output amplifier. The system is extensible and may be tailored to the individual needs of the application. A high speed programmable timing sequencer generates the CCD clock signals with timing resolution to 25 ns. Virtually any CCD clocking signals may be generated. Timing sequences and clock references for each CCD output port in the system may be separately configured. An adaptable camera system controller accepts high level commands for system operation and image acquisition. The operational parameters and command language may be modified by the user if desired and may be retained from session to session. Reconfiguration of the system to operate a different CCD requires only replacement of one circuit card and downloading a set of modified parameters. The initial version of the system is configured to perform four port operation of a Tektronix 111024 CCD at a 100 kilohertz pixel rate and a 1 megahertz rate at 16 and 12 bit resolution respectively. 1.

关键词： Charge-coupled devices digital signal processing Clocks Imaging systems Cameras Control systems CCD cameras Computing systems Analog electronics Telecommunications

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TECHNOLOGY FOR THE 90S

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IEEE CIRCUITS AND DEVICES MAGAZINE 1991年第4期7卷 13-19页

作者： [Anonymous] IEEE Circuits and Devices Magazine New York United States

A forecast of the practical and promising devices, circuits, and systems that can be expected in the next one to five years is presented. It is based on a survey of a group of distinguished practitioners throughout the industry. The forecasts cover the areas of lasers and electrooptics, integrated optoelectronics, electron devices, digital integrated circuits, high-frequency and microwave devices, VLSI signal and image processing systems, analog ICs and signal processing, power electronics and systems, neural systems and applications, and medical image and signal processing. A particularly optimistic outlook is seen for lasers, fiber optics, optoelectronic ICs, and optical switching and processing. digital ICs and power electronics are also expected to make steady gains. In addition, flat panel displays will attract a fair amount of activity, with the liquid-crystal and electroluminescent types emerging as the leaders in this decade. Looking further out, advances in artificial and biological neural systems represents a natural extension to more sophisticated problem-solving in speech processing, vision and communications.< >

关键词： optical signal processing Fiber lasers Lasers and electrooptics Masers digital signal processing Biomedical signal processing Power electronics Circuits Power lasers Electrooptic devices

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