S模式机载应答机的中频数字化处理

介绍了S模式机载应答机的中频数字化处理的设计方法.采用FPGA和高速A/D转换器实现了80 MHz的高速数字信号处理系统,解决了传统二次监视雷达(SSR)目标分辨力差、窜扰等问题,完成了二进制振幅键控(ASK)和二进制差分相移键控(DPSK)组合成的询问信号的中频数字化处理全过程.     

多光谱TDI-CMOS图像传感器读出电路设计

针对3D集成式多光谱TDI-CMOS图像传感器的数字化处理和高速读出需求,为了解决与TDICCD探测器的整体布局、物理尺寸和接口的匹配性和一致性问题,研制了适用于五谱段TDICCD的CMOS读出电路芯片。该读出电路芯片创新地设计了一种使用多相位ADC时钟、支持相关多次采样的新型列级单斜ADC电路结构,实现了TDICCD信号的数字化和高速输出,有效提升了探测器的动态范围和噪声指标。流片测试结果表明：读出电路芯片的功能正常,集成式TDICCD的成像效果良好,新型列级ADC工作正常,读出电路以最小9.5μs的行周期输出14 bit数据,相关多次采样具备降低输出信号噪声的作用,实现了TDICCD信号的高精度数字化处理和高速输出,满足3D集成式TDI-CMOS图像传感器的研制要求。     

LFMCW雷达高速运动目标检测与估计

针对LFMCW雷达高速运动目标的检测问题,本文提出了一种二次混频与MTD处理相结合的方法。根据上、下调频差拍信号对称特点,采用二次混频处理解决多周期信号中心频率偏移问题,同时实现了距离-多普勒解耦合。MTD处理则等效地实现了多周期信号的积累,并得到目标速度估计。然后根据速度估计值对差拍信号进行运动补偿,获取目标距离信息。性能分析结果表明,与传统MTD方法相比,在输入信噪比一定的情况下,该方法的处理增益不受目标多普勒的影响,因此更适用于高速运动目标的检测。仿真结果验证了该方法的有效性。     

数字化脉冲激光引信探测系统设计与信号处理

针对以往模拟脉冲激光引信探测系统存在的测距误差较大的缺点,为进一步提高脉冲激光引信的测距精度,设计了一种数字化脉冲激光引信探测系统.该探测系统包括发射、接收和信号处理3部分,其中信号处理部分主要实现脉冲回波信号的高速实时采样与缓存、信噪比增强与时延估计.采用双通道ADC并行采样,实现了以200 MHz的等效采样频率对脉冲回波信号进行高速采样.当脉冲回波信号很微弱时,采用多脉冲相干平均算法提高了其信噪比,增强了对微弱回波信号的检测能力.通过最小二乘时延估计算法得到了回波时延,进而计算得到目标距离.测距实验结果表明:该探测系统测距精度较高,最大测距误差为0.25 m.     

基于TS201芯片的雷达信号处理机设计

为了解决雷达信号处理中的高速运算,大容量存储和高速数据传输的问题,提出采用TS201芯片实现雷达信号处理机设计,利用其超高性能的处理能力和易于构造多处理并行系统的特点,实现通用的雷达信号处理平台。采用该雷达信号处理机进行试验,试验结果表明该雷达信号处理机满足设计指标要求,实现雷达信号的实时处理。     

脉冲压缩技术在雷达系统中的应用

早期雷达系统中存在着非常典型的难题,即检测能力与分辨率的矛盾,脉冲压缩为解决这一问题提供了有效的技术途径。本文对目前在雷达信号处理系统中应用较为广泛的脉冲压缩技术进行了介绍。首先对介绍了脉冲压缩技术和线形调频脉冲信号,然后介绍了线形调频信号的压缩过程及其压缩方法。     

实时频谱分析技术在雷达信号侦察中的应用

复杂电磁环境下,信号侦察系统需要宽带的信号采集和处理能力、高截获概率和快速准确的分析能力。数字化雷达侦察宽带接收机中采用实时频谱分析技术可以提高设备对信号的捕获能力和观察能力,是一种非常有应用前景的新技术。本文首先研究了实时频谱分析技术的基本原理及其两个关键技术——频率模板匹配技术和数字荧光技术,然后提出了经过频率模板匹配处理后基于数字荧光技术生成的频谱积累图进行信号检测的处理方法,并定性分析了在接收频段上存在单信号、双信号及多信号等不同情况下该方法的处理性能。对双信号和多信号情况,根据信号位置按照分离、交叉和包含三种情况进行了分析。最后给出了相应的仿真验证,假定频段上存在三个宽带信号,其中一个信号在频率模板的模板区,另外两个信号不在,对3种能分离的情况在5dB、10dB、15dB、20dB的不同信噪比下各作了100次试验,并对试验结果进行了分析。仿真结果表明,采用文中提出的处理方法,能够有效的分析处理在同一时间段内存在的多个不同信号,从而提高了雷达侦察接收机的性能。      

聚焦大屏幕拼接屏

大屏幕拼接屏是以FPGA阵列为硬件基础,采用并行高速图形处理技术,实现了多路高速视频信号的统一处理,从根本上取代插卡式拼接控制器,解决了VGA信号输入数量受到限制的问题。     

基于高速CCD器件信号采集的控制DMA传输

针对高速度CCD器件输出信号数字化处理后数据存储速度要求高,单片机控制存储难以满足要求的问题,提出一种基于高速A/DTLC5510的DMA(directmemoryaccess)单片机控制系统有效解决了该问题。该系统数据采集速度可达167ns/次。     

基于FPGA的快速傅立叶变换算法实现

电力系统自建成以来就存在着电力系统谐波问题,随着数字化装置的广泛应用,电力谐波成为影响电力系统稳定性的一大因素。为解决快速傅立叶变换算法(FFT)的频谱泄漏问题,本文采用了基于FPGA的线性插值实现对电力系统工频频谱泄漏问题改善和实时谐波分析和检测。通过研究表明,基于FPGA的FFT对电力系统谐波检测具有运算大、精度高、高速度的特点,从而实现了对谐波信号的实时监测处理。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks