高光谱RX异常检测的多DSP并行化处理技术

为达到高光谱图像数据RX异常检测处理的高速、实时、海量存储等要求,本文提出了一种基于 CPCI Express 标准总线架构的多DSP高光谱图像并行处理系统的解决方案。系统采用4片DSP共享数据总线和存储器的紧耦合与Link口互联相结合的硬件拓扑架构。在该硬件平台上,针对光谱RX异常检测算法以及光谱图像三维数据的特点,分配各DSP并行处理任务,提出了一种利用图像空间分块计算并求整个图像的均值矩阵与协方差矩阵的4DSP并行处理技术。结果表明,在保证同等探测效果的条件下,采用本文的RX异常检测算法4DSP并行处理技术,可以达到单DSP处理4倍的时间效率,解决了DSP内存容量对大数据量图像处理的限制,并较好的完成了光谱数据的实时处理要求。     

Nonuniformity correction algorithm based on adaptive filter for infrared focal plane arrays

Response nonuniformity is a key problem that influences the imaging performance of infrared focal plane arrays (IRFPA) imaging system. A parallel processing algorithm to adaptively estimate the nonuniformity correction (NUC) parameters for IRFPA is presented. In this algorithm, a bank of the adaptive filter is applied to adaptively estimate the NUC parameters for every detector in IRFPA. The infrared image sequences are input into the bank of adaptive filter. After certain times recursion calculations are executed frame-by-frame, then the optimal coefficients of the gain and the offset of detector in IRFPA are achieved. Then the NUC is fulfilled ultimately. The algorithm reduces the influence that the response drift with time imposed on NUC effectively, and achieves good NUC effect. It was validated by real experimental imaging procedures.     

兰州重离子加速器控制系统DSP组件设计

针对重离子加速器部分电源的控制要求,进行了分析研究,提出并实现了一种实时、高效、多功能的控制系统。该系统基于数字信号处理器（DSP）和两片现场可编程门阵列（FPGA）芯片相结合的核心处理构架,在系统后端利用PXI总线接口配合FPGA来与工控机箱中的系统控制器和其他控制组件进行大批量数据交互;系统前端利用直接数字频率合成器、模数转换器和数模转换器等器件结合DSP和FPGA中的控制算法及相应控制机制来实现对不同电源控制参数的处理和功率的输出;平台中两组光纤模块也与FPGA相配合实现对同步触发事例等实时数据的收发和调试。     

多核DSP高速实时信号处理系统设计

介绍了基于TI公司多核定点DSP(TMS320C6474)的高速实时数字信号处理系统。系统利用FPGA作为控制单元和转接芯片,通过SRIO接口作为DSP芯片的数据输入输出接口,具有信号处理能力超高、输入输出接口简洁、以及存储能力较大的优点。在软件实现中,利用了乒乓数据吞吐,静态内存分配技术和三核软件同步机制,通过优化算法,高效地实现了三核DSP实时信号处理,计算效率达到了设计要求。在项目图像信号实时处理中得到了成功应用,取得了良好的效果。     

基于逆透视变换的车辆排队长度检测方法

交通路口的车辆排队长度检测是智能交通系统的重要组成部分,传统的检测方法易受背景噪声、摄像机透视效果等因素的干扰造成检测失败,而且其实现都是基于串行结构的处理器,不能用于实时处理的场合。本文设计了一种充分利用平直道路几何特征并适合FPGA实现的排队长度自动检测算法,该算法利用逆透视变换消除图像几何失真,引入公路的结构性约束有效检测了车道线;接着采用Sobel边缘算子检测出各车道的车辆轮廓,通过一种基于信息量的度量方法提取排队的队尾,从而确定了车辆排队长度,并且通过硬件化设计使得整个检测过程达到实时的处理速度。     

用基于DSP的线阵CCD实现二维图像信号采集的系统设计

对光电转换系统，尤其是采集信号的后处理进行了研究。介绍了在光电精密数据采集处理中通过DSP用硬件实现对CCD信号的采集和处理过程。给出了对CCD信号进行边缘识别的微分算法和将线阵CCD信号进行组合，恢复出二维图像信号的算法。同时还给出了详细的硬件处理电路。重点介绍了DSP与FIFO的数据传输、DSP与USB的接口电路。解决了一般情况下系统无法做到的用线阵CCD实现二维图像信号复原的问题。通过实验，证明了该方法的有效性。线阵CCD信号是以若干线段的形式存在的，特别适用于激光雕刻机图像采集系统，应用前景广阔。     

基于NiosⅡ的非制冷红外图像处理系统研究

设计一个非制冷红外图像处理系统，该系统放弃了目前普遍应用的数字信号处理器（DSP）＋现场可编程门阵列（FPGA）的系统构架，采用基于FPGA的NiosⅡ嵌入式处理器的系统构架，实现了系统的小型化。提出一种基于流水线结构的信号处理方法，并利用NiosⅡ嵌入式处理器软硬件开发工具，实现了在该系统上对非制冷红外焦平面阵列非均匀性进行校正和盲元补偿的实时处理，降低了系统的工作频率。实验结果表明：该系统能够对非制冷红外图像进行实时处理，工作性能稳定，处理效果良好。     

基于FPGA联合Sobel算法的实时图像边沿检测系统的设计与实现

边沿检测技术作为数字图像处理领域的重要一支,在目标匹配,交通管控,国防安全等多个领域有着广泛的应用,能够精确高效地实现边沿检测对于后续进行更高层次的图像识别以及图像处理有着密切的联系。为了实现实时有效的图像边沿检测提出了基于FPGA结合Sobel算法的实时图像边沿检测系统,硬件使用流水线结合并行处理的解决方案,能够有效提高图像处理的速度;算法设计采用Sobel算法,不但简化了运算同时获得了不错的检测效果。实验结果显示,系统可高效地达成实时图像边沿检测的设计目的,而且提升了图像的处理效率与边沿检测的效果,便于满足后续图像处理的要求。     

基于自适应滤波的红外焦平面阵列非均匀性校正算法

 红外探测器响应漂移特性会降低红外焦平面阵列（IRFPA）非均匀性校正的精度。针对该问题提出了一种基于场景的IRFPA非均匀性校正算法。该算法利用所获得的序列成像场景信息,采用一种基于快速自适应滤波器的最优化递归估计方法来获得非均匀性校正参数,并利用当前的成像信息来更新校正参数,以此降低探测器响应漂移特性对非均匀性校正的影响。算法仿真实验显示,对非线性参数为26.12%的同一图像,使用该算法、两点校正算法和卡尔曼滤波校正算法校正1 h后,可分别将非线性参数降至1.856%,3.122%和1.893%,说明该算法可获得稳定而较好的非均匀性校正效果。     

基于FPGA的实时图像增强设计

局部直方图均衡是以全局直方图均衡化方法为基础,对图像中每个像素点所在的邻域范围求出灰度转换函数,然后仅应用在该中心点处。为了提高算法的运算速度,特别是在处理视频图像时,采取传统的DSP的设计方法在速度上很难满足需要,因此,利用FPGA实现是一个很好的选择。为使局部直方图均衡方法能够在FPGA上具体实现,从空间域的角度改进了图像灰度直方图均衡算法,并利用VHDL语言对算法进行了完全可综合的RTL级描述,最后在硬件平台上验证了结果。     

Parallel performance of the fine-grain pipeline FPGA image processing system

The use of FPGA circuits in imaging systems increases. They compete with other computing environments. The article describes the indications to be followed while choosing the type of image processing computing system taking under consideration the advantages and disadvantages of each technology: general purpose processor, digital signal processor, graphical processing unit, application specific Integrated circuit and field programmable gate array. Attention is drawn to various video transmission standards. The state of research and development trends in the field of FPGA-based image processing are briefly presented. A defining processing performance method for image processing is proposed. It is proven that for a pipeline architecture implemented in FPGA, a linear speedup is achieved and parallel efficiency is equal to one.     

基于DSP和FPGA的图像选别系统设计

色选设备是集光、电、气、机及图像处理为一体的高科技综合技术。基于DSP和FPGA的图像选别系统具有精度高、处理速度快、集成度高、功耗小等优点。首先介绍图像选别系统的硬件组成,然后以破损花生检测为研究对象,通过Matlab编程研究不同处理算法的优缺点,最后移植到DSP上测试编写的程序,提出破损花生的检测算法,实现了依据破损面积大小对花生的选别。在花生筛选中,除了破损花生检测,还有花生的大小检测,因此在上述基础上进一步提出花生几何参数的计算方法。     

Nonuniformity correction algorithm with nonlinear model for infrared focal plane arrays

For the detector in infrared focal plane arrays (IRFPA) with a large dynamic range of response, a nonlinear model of response curve of the detector in IRFPA is introduced in this paper. With the model, the Kalman-filter nonuniformity correction (NUC) algorithm with linear model, developed by Torres and Hayat, is extended. In the extended algorithm, the raw image is translated into a linearized one firstly by directly employing a logarithm-based transformation. Then the linearized image is corrected by the Kalman-filter NUC algorithm with linear model, and the corrected linearized image is obtained. Finally the uniformity image of the original one is achieved by fulfilling an exponent transformation to the corrected linearized image. The presented algorithm not only inherits the advantage of the original algorithm that resolves the problem of the temporal drift in the gain and the bias in each detector by updating NUC parameters with information of the current scene, but also reduce the influence of the detector nonlinear response to the NUC performance, so it is suitable for IRFPA under large response-range. The NUC ability of the presented algorithm is demonstrated by experiments with real infrared image sequences.     

A novel adaptive synchronization algorithm for intermediate frequency architecture CO-OFDM system

An adaptive algorithm of fine synchronization for intermediate frequency architecture coherent optical orthogonal frequency division multiplexing (CO-OFDM) transmission system is proposed. The whole synchronization procedure is separated into two steps. In the first step, we use an auto-correlation-style algorithm to achieve the coarse symbol synchronization. In the second step, the proposed algorithm is used to achieve the adaptive fine synchronization. The merit of the proposed algorithm is that it can realize fine synchronization under different environments without adjusting the detect-threshold of timing metric in a dynamically reconfiguration network. And also the algorithm can implement in field-programmable gate array (FPGA) or other digital signal processing (DSP) chips easily. In this paper, the CO-OFDM model is analyzed in theory firstly. Secondly, an analysis on the performance of coarse synchronization algorithm used in this paper is made. Finally, the proposed fine synchronization algorithm is introduced in detail. The simulation experiment result demonstrates that the proposed algorithm achieves fine synchronization under different signal noise ratio (SNR) conditions after 6 fiber-spans transmission.     

基于OMAPL138 FPGA构架的PC104主板检测系统

为了对PC104主板进行自动检测,分析了PC104主板工作原理及其总线时序,提出了一种基于ARM FPGA的嵌入式检测系统的设计方案。该方案采用德州仪器(TI)双核架构的高性能芯片OMAPL138中的ARM核来实现检测系统的应用管理,DSP核实现数据的处理,并利用FPGA技术来实时采集PC104总线数据。检测系统在Linux操作系统下,通过人机交互方式实现了PC104主板的各种功能的自动检测。实验结果显示该检测快速可靠,为PC104主板的自动检测提供了一种有效的方法。     

多源图像融合算法实时优化方法北大核心CSCD

针对红外与可见光图像融合的实时性要求,介绍了一种解决目前高清或超高清多源图像拉普拉斯金字塔图像融合算法的实时实现方法。基于视频数据流设计了拉普拉斯金字塔并行流水线处理结构,分析了各流水线之间的时延及优化思路。通过片上缓存的方式补偿时延时间差,实现了算法的流水等长,保证了处理数据的完整性。该方法可以在赛灵思7系列及以上的可编程门阵列(field programmable gate array,FPGA)芯片上实现双通道1080×1920@60 Hz视频图像的5层拉普拉斯金字塔融合。实验结果显示,该实时并行处理方法融合效果良好,一帧图像的融合仅需10.535 ms,处理时延小于1 ms。     

Integration of digital signal processing technologies with pulsed electron paramagnetic resonance imaging

The integration of modern data acquisition and digital signal processing (DSP) technologies with Fourier transform electron paramagnetic resonance (FT-EPR) imaging at radiofrequencies (RF) is described. The FT-EPR system operates at a Larmor frequency (L(f)) of 300MHz to facilitate in vivo studies. This relatively low frequency L(f), in conjunction with our approximately 10MHz signal bandwidth, enables the use of direct free induction decay time-locked subsampling (TLSS). This particular technique provides advantages by eliminating the traditional analog intermediate frequency downconversion stage along with the corresponding noise sources. TLSS also results in manageable sample rates that facilitate the design of DSP-based data acquisition and image processing platforms. More specifically, we utilize a high-speed field programmable gate array (FPGA) and a DSP processor to perform advanced real-time signal and image processing. The migration to a DSP-based configuration offers the benefits of improved EPR system performance, as well as increased adaptability to various EPR system configurations (i.e., software configurable systems instead of hardware reconfigurations). The required modifications to the FT-EPR system design are described, with focus on the addition of DSP technologies including the application-specific hardware, software, and firmware developed for the FPGA and DSP processor. The first results of using real-time DSP technologies in conjunction with direct detection bandpass sampling to implement EPR imaging at RF frequencies are presented.     

Active noise control in a duct by an analog neural network circuit

Conventional active noise control (ANC) in ducts has been realized with digital signal processing. The physical size of the conventional ANC systems is usually large owing to the signal processing interval, and the cost of the system depends on the price of the digital signal processor (DSP). This paper proposes a new ANC system with an analog neural network circuit, which will process signals in short time periods without DSP. The proposed neural network circuit has a simple structure consisting of analog multipliers and an integrator, and we simulated the performance of the circuit by HSPICE. We also fabricated a circuit connected to a real duct and confirmed operation of the proposed ANC system.     

基于FPGA+DSP的数据采集系统设计与实现

文章阐述了一种基于FPGA+DSP构架的数据采集系统的设计与实现。该系统中FPGA先进行模拟量、频率量、离散量输入的采集,以及RS-422、ARINC429总线的数据接收工作,然后将采集和接收到的数据按约定数据格式,通过HPI发送至DSP,DSP按协议要求完成数据的运算、组合等处理后,FPGA控制HPI读取处理结果并控制离散量输出模块、RS422、ARINC429总线按照所需的数据格式和通讯周期将数据输出至相对应的系统。该系统具有丰富的接口,能满足多种类、不同时序周期的总线通讯。     

空间太阳望远镜星载图像压缩系统的研究

受存储容量和对地传输能力的限制,空间太阳望远镜(Space Solar Telescope,SST)15个CCD采集的科学数据必须在轨进行5倍的压缩。在分析了SST对图像处理的需求基础上;综合中德合作的离线压缩方案,以及国内的设计能力,提出实时在线压缩的方案;采用基于小波变换的压缩算法,DSP和FPGA器件,设计了星载压缩系统(Onboard DataCompression Unit,DCU)。仿真实验表明上述方法满足SST系统需求。