Parametric GLRT for Multichannel Adaptive Signal Detection

This paper considers the problem of detecting a multichannel signal in the presence of spatially and temporally colored disturbance. A parametric generalized likelihood ratio test (GLRT) is developed by modeling the disturbance as a multichannel autoregressive (AR) process. Maximum likelihood (ML) parameter estimation underlying the parametric GLRT is examined. It is shown that the ML estimator for the alternative hypothesis is nonlinear and there exists no closed-form expression. To address this issue, an asymptotic ML (AML) estimator is presented, which yields asymptotically optimum parameter estimates at reduced complexity. The performance of the parametric GLRT is studied by considering challenging cases with limited or no training signals for parameter estimation. Such cases (especially when training is unavailable) are of great interest in detecting signals in heterogeneous, fast changing, or dense-target environments, but generally cannot be handled by most existing multichannel detectors which rely more heavily on training at an adequate level. Compared with the recently introduced parametric adaptive matched filter (PAMF) and parametric Rao detectors, the parametric GLRT achieves higher data efficiency, offering improved detection performance in general.     

多信道射频信号相位检测技术的研究与实现

建立了多信道相控发射机的系统模型,为了满足该系统模型在空间波束合成过程中射频信号同频同源、相位可控的要求,提出了一种高精度的多信道射频信号的相位检测技术。该技术基于数字信号处理,可以精确有效地检测不同信道之间的相位差,为实现射频信号的信号同步提供了可能。经过实际发射系统的实验证明,该技术能够并行检测多信道射频信号的相位,成功实现了多信道射频信号的同步。     

基于PC机的信号处理机

介绍一种基于PC机的信号处理机，并给出硬件框图和软件流程图。     

多通道复信号检测中的几种常用复统计分布

 复随机变量的概率密度函数(PDF)及其积累分布函数(CDF)是复值信号检测中计算虚警概率(PFA)和检测概率(PD)的基础.本文分析了复统计分布与实统计分布之间的关系,推导了复F分布和复贝塔分布(中心或者非中心)的PDF和CDF,推导了中心复t分布的PDF,并且给出了部分应用实例.     

一种提高遥测信号处理器测试性方法

针对遥测信号处理器的设计原理,增加少量硬件电路,利用其自身FPGA剩余逻辑资源完成自检模块设计,实现了信号处理器BIT测试功能,提高了信号处理器在挂机状态下的测试覆盖率和故障检测率。     

一种数字信号处理器的动态功耗管理方案

动态功耗管理是一种系统级低功耗设计技术，降低功耗的思路是根据系统当前负载动态调整时钟频率或者关闭时钟。文章以数字信号处理器为模型，提出了一种系统属性可调节的动态功耗管理方案，它支持通过软硬件配合对功耗进行灵活的动态管理，其管理策略采用了适应性预测算法，并引入非确定性因子。实验结果表明，该方案可以大大降低数字信号处理器的功耗。     

An Efficient Adaptive Filter Architecture for Improving the Seizure Detection in EEG Signal

This paper presents efficient low-power adaptive filter architecture for electroencephalogram (EEG) signal and epileptic seizure detection using recurrence quantification analysis (RQA). The preprocessing of EEG is done using notch, wavelet and adaptive filter. The comparison of signal-to-noise ratio of the filter outputs proves that the adaptive filter provides better performance and a parallel interleaved sample of direct form adaptive FIR filter architecture is implemented and low-power issues are addressed. An innovative compressor-based addition technique is utilized in the filter implementation to reduce the area and power consumption. The design is developed using Verilog HDL and mapped to 65-nm technological node. The power results are compared with conventional architecture of adaptive filter. The major advantage of choosing RQA is that it provides better information even for short non-stationary and nonlinear signals where other methods fail to provide good results. And it requires no conventions about data set size or dispersal of the data. The algorithm is applied on epileptic EEG signal from CHB-MIT database. The RQA measures are determined from the recurrence plot, its performance is measured in terms of sensitivity and specificity as 97.4 and 93.5 %, respectively, and leakage power is reduced to 10 %.     

某雷达信号处理机调试台的设计

在雷达系统中,信号处理机是核心部件之一,其性能参数及可靠性直接影响到雷达系统的性能。怎样全面系统测试信号处理机,是我们关心的问题。本文介绍了一种有效的信号处理机测试平台的设计。     

基于小波的多路信号估计方法

从带噪信号中估计源信号在很多应用领域都是重要课题,例如通信、医学成像、远程图像以及天文学等等。估计多路信号是其中的一个小子集。本文阐述了最近提出的基于小波的多路二维信号估计方法。这种方法通过离散傅立叶变换(DFT)和二维离散小波变换(DWT)近似最佳地使数据解相关,从而充分地利用了信道内和信道间信号的相关性。同时,运用Normal Shrink降噪算法改进估计结果。     

一种实用的红外弱小目标检测跟踪处理机研究

以小波变换作为对红外弱小目标进行检测识别的核心算法，并根据该算法搭建了基于FPGA和DSP的红外信号处理器的硬件平台。该平台在FPGA上实时完成了离散小波变换算法，可用于检测弱小目标，并通过DSP实现了稳定地跟踪。结果表明，该设计的方案对红外弱小目标的检测识别和跟踪具有实际意义。     

A Multiplexing System for Multichannel Signal Averaging of the Visual Evoked Response

Time-division multiplexing allows 24 channels of evoked potential data to be recorded on a seven track instrumentation tape recorder and later played back into a signal averager where it is simultaneously demultiplexed and averaged. Complimentary metal-oxide-semi-conductor (CMOS) switches provide a simple, low-cost way of increasing the number of recorded channels when the bandwidth of the recorder is sufficiently high.     

A Simple Signal Processor for a Respiratory Rate Monitor

Although respiratory rate is a desirable patient parameter to monitor, signals from a spontaneously breathing patient are so irregular that reliable counts have been difficult. This short communication describes a circuit that processes the signal produced by a respiratory transducer (in our case an impedance pneumograph), and provides a countable output to a digital rate monitor. It is relatively simple, but embodies complex decision criteria in identifying respiratory activity.     

A High Performance LSI Digital Signal Processor for Communication

This paper describes a newly developed CMOS LSI DSP (FDSP3). It has a powerful multiplier, which operates at a rate of 10 M-operations/s, almost twice as fast as the fastest existing LSI DSP's. Some key techniques to attain these high performance characteristics of the DSP are described. Suitable memory capacities of the RAM and ROM were analyzed as a function of the operational capability of the DSP. These were reflected in the design of the FDSP3. To assist in the development of the program, support tools have been developed. A Pascal based cross compiler and an on-line debugging tool are described in some detail.     

一种通用雷达信号处理机的设计

在基于VME总线或CPCI总线的雷达信号处理机中，板与板之间的数据传输速率受限于总线的速率。针对现有的雷达信号处理机板间的数据传输速率较低的问题，本文提出了一种新的设计方法，即采用DSP和FPGA相结合的设计方法，利用FPGA提供的高速串行收发通道进行板间的数据传输，使板间的数据传输速率获得大幅度的提升，同时也有效地改善了板内DSP间的数据传输问题。     

高分辨率SAR实时信号处理

介绍了高分辨率合成孔径雷达实时信号处理机硬件结构和实时信号处理算法及流程。该信号处理机的核心是G4模块，包含4个矢量处理芯片MPC7410，G4模块具有存储容量大和运算速度快的特点。算法上采用工程上较易实现的R-D算法及对比度最优自聚焦算法。利用机载SAR试飞数据验证，得到了高分辨率SAR图像，证明信号处理机稳定有效可靠。     

一种ESM系统信号处理的设计方法

针对电子支援措施(ESM)的技术要求,分析了ESM信号处理机的主要技术特点,提出了基于信号预处理和信号主处理的两级工作方式,并利用典型算法说明了ESM信号处理机组成及工作原理。给出了以未知信号预分选、已知信号预分选、脉冲重复间隔(PRI)分选、参数估计、雷达信号跟踪处理为主要模块的信号流程,并按模块的执行流程和原理组织了适合应用的硬件框架结构。     

一种新型通用可编程雷达信号处理器

介绍一种新型通用可编程雷达信号处理器,包括其处理功能、电路设计特点及应用。     

模块化信号处理机技术探讨

叙述模块化信号处理机的基本组成和工作原理 ,对信号处理过程中部分关键技术和发展趋势进行探讨     

动目标检测雷达数字信号处理机内建自测试研究

提出了一种动目标检测雷达数字信号处理机内建自测试方法。该方法介于系统级和板级之间,集系统调试、在线测试和离线测试于一体,设计简单,易于实现。论证了处理机各个关键模块的具体测试方法。针对其中的“数据存储重排”模块和“ Ｆ Ｆ Ｔ 与求模”模块,计算了故障覆盖率。