小型CRT－LCLV组合器件

选用１英寸阴极射线管（ＣＲＴ）和液晶光问（ＬＣＩ－Ｖ）研制成直径１英寸的ＣＲＴ－ＬＣＬＶ组合器件，介绍了组合器件的工作原理、制作工艺和性能指标，并给出了在小型光学相关器上的应用实例．     

A simplified optical correlator for radar-signal Processing

Radar-signal processing is an interesting application of optical correlators. A simplified optical correlator is described and experimental results are presented.     

Automatic speaker verification: A review

The relation of speaker verification to other pattern-recognition problems in speech is discussed, especially the distinction between speaker verification and speaker identification. The prospects for automatic speaker verification, its settings and applications are outlined. The techniques, evaluations, and implementations of various proposed speaker recognition systems are reviewed with special emphasis on issues peculiar to speaker verification. Two large-scale operating systems using different analysis techniques and applied to different settings are described.     

Optical pattern recognition: architectures and techniques

This article addresses the development of and recent advances in the rapidly growing field of optical pattern recognition. In optical pattern recognition there are two basic approaches; namely, matched filtering and associative memories. The first employs optical correlator architectures and the latter uses optical neural networks (NNs). This paper reviews various types of optical correlators and NNs applied to real-time pattern recognition and autonomous tracking. Techniques of scale and rotational invariant filtering are also given. Recent approaches using wavelet transform filtering, phase only filtering, high capacity composite filters and phase representation for improvement in pattern discrimination are also provided     

基于联合变换／匹配滤波光学相关器的自动目标识别

研制一种新型超高速智能信息处理系统，该系统采用联合变换光学相关器和匹配波光学相关器组合结构，并在一套光路上用联合变换光相关器来进行目标跟踪，用匹配滤波光学相关器进行目标识别，实验表明这种方法效果良好。     

Two-state pattern-recognition handoffs for corner-turningsituations

Handoff algorithms are used in wireless cellular systems to decide when and to which base station to handoff. Traditional handoff algorithms generally cannot keep both the average number of unnecessary handoffs and the handoff decision delay low. They do not exploit the relative constancy of path loss and shadow fading effects at any given location around a base station. However, handoff algorithms with both a negligible number of unnecessary handoffs and a negligible decision delay can be realized by exploiting this information. One example is the set of handoff algorithms using pattern-recognition introduced in previous work. In this paper, we describe how pattern-recognition handoff algorithms can be applied to the problem of turning a corner. This can be used as part of an integrated pattern-recognition handoff algorithm or together with a traditional handoff algorithm, in which case the pattern-recognition handles only the special cases like turning a corner     

Fast optical recording media based on semiconductor nanostructures for image recording and processing

Fast optical recording media based on semiconductor nanostructures (CdTe, GaAs) for image recording and processing with a speed to 10⁶ cycle/s (which exceeds the speed of known recording media based on metal-insulator-semiconductor-(liquid crystal) (MIS-LC) structures by two to three orders of magnitude), a photosensitivity of 10^?2V/cm², and a spatial resolution of 5–10 (line pairs)/mm are developed. Operating principles of nanostructures as fast optical recording media and methods for reading images recorded in such media are described. Fast optical processors for recording images in incoherent light based on CdTe crystal nanostructures are implemented. The possibility of their application to fabricate image correlators is shown.     

Photonic Signal Processing of High-Speed Signals Using Fiber Gratings

Methods for wideband photonic signal processing using fiber delay lines and Bragg grating sampling elements are described. These processors provide new capabilities for the realization of high time-bandwidth operation and high resolution performance. Multiple wavelength techniques with discrete and chirped Bragg gratings are described, which have high capacity signal processing functions using dense parallel signal processing techniques. Both fixed and tunable or reconfigurable processors using wavelength control to change the sampling time are discussed. A range of grating-based signal processors, including high Q microwave filtering, frequency discriminators, widely tunable filters, fast and adaptive signal correlators, and true-time delay beamforming in phased array antennas are described.     

Acoustooptic interactions and devices

A review of recent advances in the understanding of the interaction of light and ultrasonic waves in solids and liquids is presented, emphasizing the Bragg diffraction regime wherein the diffracted optical energy is confined near one angular direction. The usefulness of optical beam probing techniques, using laser light sources, for investigating such subjects as ultrasonic attenuation and diffraction, acoustic nonlinear phenomena, magnetoelastic interactions, and photoelastic properties of materials is described. The application of the acoustooptic interaction for the design of devices intended to perform optical information processing functions is also mentioned. Present applications include optical modulators, switches, sequential scanners (such as are useful for television display), random access optical deflectors, and optical correlators. An attempt is made to describe the assets and liabilities of acoustooptic devices and to speculate concerning their future in the practical world.     

Optical readout from plasma display/memory panels

Techniques for extracting stored information from an array of plasma display elements using optical detection systems are presented. Two specific electronic drive schemes and several experimental area photodetector systems used in realizing readout capability in display systems are described. Limitations of optical read-out systems due to optical noise generated by the display panel and by incident ambient light are discussed.     

一种新型的相关接收技术

本文论述了一种新的相关技术——声光相关，提出了两种空间积分声光相关器对扩频信号进行相关处理的方案并给出了实际的光学结构，具体探讨了这两种处理器用于扩频信号的同步和解调技术，给出了具体的例子     

3.6微秒存储相关器读写实验及结果

通过在单片式MZOS结构卷积器中制作pn结二极管阵列,制成了这种结构的存储相关器/卷积器。我们利用这种器件作了对信号的存储、相关和卷积等一系列实验,描述了器件性能及工作方式和原理,为存储相关器作为信号处理器件的应用开发提供了有益的参考。     

Slot Synchronization in Optical PPM Communications

Maintaining slot clock synchronization in a baseband pulse position modulated (PPM) communication link is vital to its performance. This paper examines the slot clocking design associated with a direct detection, photodetecting optical PPM system. Although theoretical PPM synchronizers for optical links have been derived in the past, there is still interest in finding more practical, simpler, and easier-to-implement clocking subsystems. In this paper several types of practical slot synchronizers are considered. A basic design involving analog correlators and slot gating is presented, along with an indication of its performance. Several alternative designs are also presented, including digital synchronizers in which time samples are used for loop control. The advantage in digital systems is that more extensive processing can be handled in software, allowing the loop to perform closer to the ideal. Design procedures for digital clocking are presented, and optimal laser pulse shaping and filtering are discussed. Performance in terms of loop models and tracking error variance is included.     

Multiplexing Techniques for Digital Correlator Speed Improvement

Several approaches to time-division multiplexing of digital correlator devices are developed wherebykoperations are overlapped in time. Where synchronization with the input signal exists, the resulting multiplexed correlators providek-fold speed improvement over individual correlator devices. A completely synchronized correlator can be formed fromksuch multiplexed correlators by proper selection of outputs. A simplified realization is presented which only requires one set ofk N/k-bit signal and reference registers andksets ofN-bit comparator circuits. Laboratory experimentation and computer simulations to support these concepts are described.     

综合孔径微波辐射计二阶量化数字相关器研究

微波辐射计作为一种无源遥感器,在遥感技术领域有着巨大的应用前景.传统的微波辐射计的空间分辨率受到天线孔径的限制.综合孔径微波辐射计利用了干涉测量原理和复相关技术,是一种可以有效地提高空间分辨率的新型辐射计.本文针对综合孔径微波辐射计的数字相关器进行了深入研究,分析论证了二阶量化数字相关器的工作机理,并对采用该种相关器的系统的信噪比进行了分析.初步的试验验证结果证明了该方案的有效性.     

直扩接收机基带迟早门跟踪环的简化设计

针对要求设计简化、资源有限的设备和系统 ,通过对直扩接收机基带迟早门跟踪环的性能分析 ,在扩频增益比较大时 ,提出了一种简化设计结构 ,用两个由扩频码的部分序列构成的相关器分别替代原来早门和迟门的完全序列相关器。仿真表明该结构在给定足够的相关值情况下 ,性能略有恶化 ,但资源却得到较大节约 ,设计可大大简化。     

Pattern Code Modulation and Optical Decoding--A Novel Code-Division Multiplexing Technique for Multifiber Networks

We consider the use of multiple high-capacity fibers for communications networking. Each user transmits, asynchronously, patterns of optical pulses distributed over the fibers and throughout a time frame. Each receiver has a distinct alphabet of patterns, which are detected by optical correlators. Optical correlation by fiber tapped delay lines provides speedy and easy-to-implement decoders. Thus the individual user obtains a transparent low-speed channel by code multiplexing. The reliability of this low-speed channel can be enhanced by redundantly coding the patterns sent by the user, for which the encoding and decoding processes can be performed electronically. This two-step encoding process is simple to implement, highly reliable at reasonable throughput, and provides asynchronous access with simple protocol. Various components and configurations of this access scheme are described. The information theoretic capacity and the error probability for these configurations are derived. We also demonstrate that hardlimiting and filtering at the receiver reduce error probability significantly.     

Applications of traveling-wave laser amplifiers in subcarriermultiplexed lightwave systems

Describes applications of traveling-wave laser amplifiers (TWLAs) in subcarrier-multiplexed distribution systems for both frequency-modulated (FM) and amplitude-modulated vestigial-sideband (AM-VSB) video signal distribution. The characteristics of a 1300-nm facet-angled and antireflection-coated TWLA are described. Analytical carrier-to-noise ratio (CNR) characterizations of subcarrier-multiplexed systems employing TWLAs are given. Experimental results of using TWLAs in multichannel FM and AM-VSB video signal systems are described. The potential optical-reflection problems associated with the residual reflectivities of optical fiber connectors and splices while using TWLAs are briefly described     

Micromachining for optical and optoelectronic systems

Micromachining technology opens up many new opportunities for optical and optoelectronic systems. It offers unprecedented capabilities in extending the functionality of optical devices and the miniaturization of optical systems. Movable structures, microactuators, and microoptical elements can be monolithically integrated on the same substrate using batch processing technologies. In this paper, we review the recent advances in this fast-emerging field. The basic bulk- and surface-micromachining technologies applicable to optical systems are reviewed. The free-space microoptical bench and the concept of optical prealignment are introduced. Examples of micromachined optical devices are described, including optical switches with low loss and high contract ratio, low-cost modulators, micromechanical scanners, and the XYZ micropositioners with large travel distance and fine positioning accuracy. Monolithically integrated systems such as single-chip optical disk pickup heads and a femtosecond autocorrelator have also been demonstrated     

多片C40并行处理实时相关器

本文介绍了一种用于多道地震数据采集系统的实时相关器，它根据地震数据的的特点和对实时相关处理的要求，采用目前最先进的数字信号处理器TMS320C40，构成了一个多片C40并行数据处理系统，文章介绍了实时相关器的并行结构以及C40相关运算的软件流程，最后结出了测试结果。