基于FPGA的雷达侦察信号预处理器

针对当前复杂、密集的电磁环境,提出了以数字逻辑硬件电路实现预处理器的必要性,简要介绍了三参数关联比较器的原理及特点,并对设计中的几个要点进行了说明。     

Error Probability Analysis for Ultra-Massive MIMO System and Near-Optimal Signal Detection

In this paper, average bit error probability(ABEP) bound of optimal maximum likelihood(ML) detector is first derived for ultra massive(UM) multiple-input-multiple-output(MIMO) system with generalized amplitude phase modulation(APM),which is confirmed by simulation results. Furthermore, a minimum residual criterion(MRC) based lowcomplexity near-optimal ML detector is proposed for UM-MIMO system. Specifically, we first obtain an initial estimated signal by a conventional detector, i.e.,matched fil...     

一种多用途水声信号预处理机的设计与实现

介绍了一种多用途水声信号预处理机的具体设计,详细阐述了各模块电路的设计原理及工程实现,给出了部分电路的原理图。实验结果表明,所研制的预处理机白奇各项参数都达到了预期设计要求,具有低噪声、高增益、大动态范围和滤波可编程的特点,在教学和科研实验中取得了满意的应用效果。     

Finding Near-Optimal Regularization Parameter for Indoor Device-free Localization

Device-free Localization (DfL) systems offer real-time indoor localization of people without any electronic devices attached on their bodies. The human body influences the radio wave propagation between wireless links and changes the Received Signal Strength (RSS). Wireless Sensor Networks (WSNs) nodes easily measure these RSS changes and appropriate Radio Tomographic Imaging (RTI) algorithms can then process the RSS data and allow human localization. This paper investigates how to choose near-optimal regularization parameter during the regularization process for indoor DfL and describes an experimental indoor DfL setup realized with a Sun SPOT based WSN. The work elaborates on the numerical calculation of the near-optimal regularization parameter by usage of the trade-off curve criterion. The calculated parameter enables conclusive RTI image with sufficient localization precision for eHealth or other ambient-assisted-living applications where the error tolerance is at a scale of several tens of centimeters. The value for the regularization parameter matches the empirical derived value obtained in the authors’previous work.     

A Near-Optimal Linear Crosstalk Canceler for Upstream VDSL

Crosstalk is the major source of performance degradation in VDSL. Several crosstalk cancelers have been proposed to address this. Unfortunately, they suffer from error propagation, high complexity, and long latency. This paper presents a simple, linear zero-forcing (ZF) crosstalk canceler. This design has a low complexity and no latency and does not suffer from error propagation. Furthermore, due to the well-conditioned structure of the VDSL channel matrix, the ZF design causes negligible noise enhancement. A lower bound on the performance of the linear ZF canceler is derived. This allows performance to be predicted without explicit knowledge of the crosstalk channels, which simplifies service provisioning considerably. This bound shows that the linear ZF canceler operates close to the single-user bound. Therefore, the linear ZF canceler is a low-complexity, low-latency design with predictable near-optimal performance. The combination of spectral optimization and crosstalk cancellation is also considered. Spectra optimization in a multiaccess channel generally involves a complex optimization problem. Since the linear ZF canceler decouples transmission on each line, the spectrum on each modem can be optimized independently, leading to a significant reduction in complexity.     

计算强流电子枪的SLAC预处理程序

为建立 SLAC 电子轨迹计算程序所需的 GUN.INP 文件,编制了有关预处理程序。该软件具有优良的功能,有助于提高电子枪设计的精度与效率。它已被本文所提供的设计实例所证实。     

On the detection of Cardiac Arrhythmia with Principal Component Analysis

Wireless Personal Communications - The Electrocardiogram (ECG) signal is used to record the electrical activity of heart. The subtle variations in ECG attributes are used by cardiologists for...     

A Near-Optimal Linear Crosstalk Precoder for Downstream VDSL

This letter presents a linear crosstalk precoder for very-high-speed digital subscriber lines (VDSL) that has a low run-time complexity. A lower bound on the data rate of the precoder is developed, and guarantees that the precoder achieves near-optimal performance in 99% of VDSL channels     

基于累量的OFDM信号调制识别

提出了一种快变瑞利衰落信道下的OFDM信号与单载波信号的类间调制识别新算法。接收到的射频信号经模数变换后,不需要下变频,直接进行处理。利用数字信号的2阶和4阶累量的组合作为分类特征信息,方法简单易行,不需要任何信号和信道噪声的先验知识。仿真结果表明,新算法具有良好的识别性能,在SNR不小于7 dB时能达到90%以上的正确识别率。     

基于FPGA的传像光纤束图像预处理器

针对传像光纤束成像的算法结构,提出一种基于FPGA的传像光纤柬图像预处理器设计方案。该图像预处理器相对于传统的图像预处理器具有充分利用FPGA有限的片上资源,合理安排数据操作之间的并行性和流水性等优点。具体实验结果表明,该预处理器能满足传像光纤束成像系统的实时性要求,达到预期效果。     

Local Construction of Near-Optimal Power Spanners for Wireless Ad Hoc Networks

We present a local distributed algorithm that, given a wireless ad hoc network modeled as a unit disk graph U in the plane, constructs a planar power spanner of U whose degree is bounded by k and whose stretch factor is bounded by 1 + (2sin{frac{pi}{k}})^{p}, where k geq 10 is an integer parameter and p in [2, 5] is the power exponent constant. For the same degree bound k, the stretch factor of our algorithm significantly improves the previous best bounds by Song et al. We show that this bound is near-optimal by proving that the slightly smaller stretch factor of 1 + (2sin{frac{pi}{k + 1}})^{p} is unattainable for the same degree bound k. In contrast to previous algorithms for the problem, the presented algorithm is local. As a consequence, the algorithm is highly scalable and robust. Finally, while the algorithm is efficient and easy to implement in practice, it relies on deep insights on the geometry of unit disk graphs and novel techniques that are of independent interest.     

A Novel FrWT Based Arrhythmia Detection in ECG Signal Using YWARA and PCA

Wireless Personal Communications - In general, Electrocardiogram (ECG) signal gets corrupted by variety of noise at the time of its acquisition. Unfortunately, these noise tend to mask the crucial...     

A Minicomputer System for Direct High Speed Analysis of Cardiac Arrhythmia in 24 h Ambulatory ECG Tape Recordings

A minicomputer system for the analysis of 24 h ambulatory ECG tapes at 60 times real time is presented. The unique aspect of the system is its implementation entirely in software on a single standard minicomputer system. The high scanning speed is achieved by a very efficient ectopic beat detection algorithm and a partition of the software into two phases. An on-line phase builds a reduced file of ectopic beats, which is then submitted to an off-line phase for beat classification and report generation. The entire analysis of a 24 h tape is completed in less than 30 min and requires only initialization by an operator.     

Transmitter Identification With Watermark Signal in DVB-H Signal Frequency Network

Transmitter identification (TxID) technique is used to diagnose the operating status of radio transmitters in DTV distributed transmission network. In this paper, a new kind of TxID method for DVB-H SFN(Single Frequency Network)system is proposed. We embed a signal (e.g. watermark) in the DVB-H signal to form the composite signal. The embedded signal will not alternate the system spectral efficiency. By watermarking theory, we demonstrate the required embedded level for watermarking signal to achieve a given bit error probability in different circumstance. Simulation results show that the receiver can distinguish the watermarking signal with low embedding strength even in wireless situation. At that embedding strength, BER performance degradation for the receiver can be ignored.      

通用DCME信号识别系统设计

本文提出了一种适用于各种类型DCME信号的识别系统的概念,并初步论述了系统的识别算法原理与实现方法及优缺点。     

基于信号检测法的NLOS识别

针对无线定位系统中的非视距传播(NLOS)问题,本文提出采用传统的信号榆测方法对接收信号中的NLOS信号进行检测.结合Nokia公司的现场测量数据分析得到NLOS误差信号的统计特性,根据对先验知识的掌握程度,提出分别采用广义似然比检验(GLRT)和一致最大功效检验(UMPT)检测接收信号中是否存在NLOS信号,并分别进行了两种情况下的仿真验证.仿真结果表明:基于信号检测方法的NLOS识别技术具有时间开销小,识别能力强的特点.同时由于算法理论是建立在现场测量数据的基础上,所以算法具有工程应用价值.     

Reception Power Estimation Using Transmitter Identification Signal for Single Frequency Network

In a single frequency network (SFN) based on the Advanced Television Systems Committee (ATSC) terrestrial digital television (DTV) system, receivers inevitably suffer from the interference generated by using the same frequency among multiple transmitters or repeaters. The amount of the interference can be handled by adjusting transmit power and time of each transmitter and repeater. Hence, it is crucial to estimate the individual reception power from each transmitter or repeater at the given point of interest. This paper presents an efficient method to estimate the individual reception power from each transmitter or repeater. The field test results are provided to evaluate the proposed method. The proposed method exploits the transmitter identification (TxID) signals which are embedded in existing 8-VSB signals.      

基于相位差分方法的BPSK引信信号m序列识别

该文根据二相移相键控(BPSK)引信信号脉冲相位差分和m序列的一一对应关系,通过求解脉冲相位差分方程组来得到m序列。首先,通过FFT求得脉冲相位,然后分别采用了一阶相位差分方法和二阶相位差分方法来对m序列进行识别。经计算机仿真验证,该方法是完全正确的。最后对该方法进行了可靠性分析,分析表明,即使某一个码元由于对应的脉冲相位测量误差很大而被错误识别,也不会对后续的PN码识别产生影响,说明该方法具有很高的可靠性。     

基于时域Gammatone滤波特征的广播语种识别

针对广播语种识别问题,提出一种语音时域滤波方法,用gammatone时域函数与预处理后的语音信号进行卷积滤波,再分帧加窗并求对数化能量得到时域GF(gammatone filterbank)特征.将特征参数图像化表示,然后通过VGG19和Resnet34分类网络进行语种识别实验.同时,也使用自动色阶算法对加噪语音的图像...