基于二阶滤波器的高阶带通滤波器设计和仿真

根据n阶带通滤波器传递函数的特点和低通与高通级联的思想,给出了高阶RC有源带宽可调的带通滤波器的一般设计方法和VCVS结构电路的设计步骤,并成功设计出一款高性能的四阶有源带通滤波器,其电路简单,通频带宽,精度高,成本低廉.经Multisim10仿真测试,其性能完全达到了预期效果和设计要求.     

低压低功耗运算放大器结构设计技术

低电压、低功耗、动态摆幅达到轨到轨（Rail—to—Rail）的运放是实现SOC设计的核心，而相关的输入输出模块是其中的关键技术。本文分析了两种分别工作于弱反型区和强反型区的恒跨导Rail—to—Rail输入级，同时给出了低压和极低压下两种AB类控制输出级的实现方案，并对各方案进行了比较和总结。     

Very low-voltage analog signal processing based on quasi-floating gate transistors

A novel design principle for very low-voltage analog signal processing in CMOS technologies is presented. It is based on the use of quasi-floating gate (QFG) MOS transistors. Similar to multiple input floating gate (MIFG) MOS transistors, a weighted averaging of the inputs accurately controlled by capacitance ratios can be obtained, which is the basic operating principle. Nevertheless, issues often encountered in MIFG structures, such as the initial charge trapped in the floating gates or the gain-bandwidth product degradation, are not present in QFG configurations. Several CMOS circuit realizations using open- and closed-loop topologies, have been designed. They include analog switches, mixers, programmable-gain amplifiers, track and hold circuits, and digital-to-analog converters. All these circuits have been experimentally verified, confirming the usefulness of the proposed technique for very low-voltage applications.     

有源磁控忆阻器的等效电路及滤波频率特性研究

基于三次非线性数学模型,采用通用有源电路元器件完成了一种磁控忆阻器的"浮地"二端口等效电路实现,基于Multisim电路仿真软件并搭建实际硬件电路研究了其伏安特性,进而研究了基于该有源磁控忆阻器的WC高通和低通滤波电路的频率特性,并与无源RC高通和低通滤波电路的频率特性进行了比较。软件仿真和硬件实验结果表明:有源WC高通滤波电路与无源RC高通滤波电路呈现相似的幅频和相频特性,而有源WC低通滤波电路的频率特性不同于单极点的无源RC低通滤波电路,其幅频和相频特性均呈现出多极点的特性。     

The design of wideband and low-power CMOS active polyphase filter and its application in RF double-quadrature receivers

In this work, a new technique to implement the transfer function of polyphase filter with CMOS active components is proposed and analyzed. In the proposed polyphase filter structure, the currents mirrored from capacitors and the transistors in a single-stage are used to realize high-pass and low-pass functions, respectively. The multistage structure expands the frequency bandwidth to more than 20 MHz. Furthermore, a constant-gm bias circuit is employed to decrease the sensitivity of image rejection to temperature and process variations. HSPICE simulations are performed to confirm the performance. With the current-mode operation, the low-voltage version of proposed active polyphase filters was designed. It can be operated at 1-V power supply with similar performance but with only 50% of the power dissipation of the normal-voltage version. The proposed four-stage polyphase filter is fabricated in 0.25-/spl mu/m CMOS 1P5M technology. The measured image rejection ratio is higher than -48 dB at frequencies of 6.1 MHz/spl sim/30 MHz. The measured voltage gain is 6.6 dB at 20 MHz and IIP3 is 8 dBm. The power dissipation is 11 mW at a supplied voltage of 2.5 V and the active chip area is 1162/spl times/813 /spl mu/m/sup 2/.     

Fuzzy rule-based signal processing and its application to imagerestoration

A novel signal processing technique based on fuzzy rules is proposed for estimating nonstationary signals, such as image signals, contaminated with additive random noises. In this filter, fuzzy rules concerning the relationship between signal characteristics and filter design are utilized to set the filter parameters, taking the local characteristics of the signal into consideration. The fuzzy rules are found to be quite effective, since the rules to set the filter parameters are usually expressed in an ambiguous style. The high performance of this filter is demonstrated in noise reduction of a 1-D test signal and a natural image with various training signals     

数字滤波器在数字信号处理中的应用设计

在信号处理中,滤波占有十分重要的地位.数字滤波是数字信号处理的基本方法,以FIR滤波器为基础,利用MATLB程序设计语言对低通FIR数字滤波器进行了有效的设计,应用DSP 汇编语言编程实现了该滤波器.     

基于LabVIEW的医学信号处理程序设计

近年来,随着计算机技术的不断完善和进步,医学信号数字化的需求越来越突出。而虚拟仪器技术的应用提高了医疗信号处理仪器的数字化进程,同时由于虚拟仪器技术将硬件软件化和软件模块化的特点,使得仪器具有开发周期短、通用性强和便于维修升级等特点,为研究人员节省了大量的时间和精力。本文主要讨论了采用虚拟仪器和LabVIEW分析、处理生物医学信号（心电信号、脑电信号）的方法和技术,满足了医院内部乃至在整个网络上实现辅助诊断的需求,并能分析病人病变过程。     

基于Matlab的FIR带通滤波器设计及DSP实现

借助Matlab的FDATOOL滤波器设计分析软件,设计了一种FIR数字带通滤波器,并对一段含噪语音信号进行滤波。利用汇编语言编程,在DSP上实现了该滤波器。实验结果表明,该数字带通滤波器精确,稳定性好,易于移植,具有很强的实用性与灵活性。     

基于DSP Builder的脑电信号小波处理

针对脑电信号非平稳性特点,利用小波变换对采集到的脑电信号进行滤波处理.然而小波变换巨大的计算量限制其在高速实时信号处理领域的应用,FPGA器件兼具并/串行工作方式,具有较高的并行计算能力,在现场数字信号处理领域具有较强的实时性.提出基于FPGA的小波变换系统设计方法,首先利用DB2小波对脑电信号按Mallat算法进行分解,然后采用小波重构算法去噪.试验结果表明,运用小波分解重构算法,可以对脑电信号进行实时滤波.     

基于DSP Builder的脑电信号小波处理

针对脑电信号非平稳性特点,利用小波变换对采集到的脑电信号进行滤波处理。然而小波变换巨大的计算量限制其在高速实时信号处理领域的应用,FPGA器件兼具并／串行工作方式,具有较高的并行计算能力,在现场数字信号处理领域具有较强的实时性。提出基于FPGA的小波变换系统设计方法,首先利用DB2小波对脑电信号按Mallat算法进行分解,然后采用小波重构算法去噪。试验结果表明,运用小波分解重构算法,可以对脑电信号进行实时滤波。     

单调谐滤波器参数设计及其应用

针对电力谐波给企业带来的安全生产隐患及对公用电网造成的严重污染和不利影响,本文简述了滤波器的工作原理,并结合工程实际为例,详细阐述了单调谐滤波器的特性及其设计过程,这种设计方法根据现有的设计经验,全面考虑设计的要求和条件,通过无功需求量确定出滤波器的基本参数,给出了结构简单、经济可靠的抑制谐波危害的办法。实践证明该设计方案谐波抑制效果良好,节能效果显著,在工程实践中可行。最后,实例分析的结果也证明了设计过程的合理性。     

考虑器件标称化的带通滤波器仿真优化设计

滤波器的传统设计方法计算出的电感、电容值并不能与市场上购置的电感、电容值完全对应,导致制作的滤波器技术指标降低。为此提出一种改进的LC带通滤波器优化设计方法,借助ADS对电路进行仿真优化,使仿真结果更接近于实际测试值。与传统方法相比,文中设计的滤波器提高了实际滤波器的性能;并且通过优化,使所有元件值均为市场所售器件的标称值,从而解决了因购置器件值与计算值不完全一致而导致的滤波器性能恶化。     

Ultra low-voltage low-power CMOS 4-2 and 5-2 compressors for fast arithmetic circuits

This paper presents several architectures and designs of low-power 4-2 and 5-2 compressors capable of operating at ultra low supply voltages. These compressor architectures are anatomized into their constituent modules and different static logic styles based on the same deep submicrometer CMOS process model are used to realize them. Different configurations of each architecture, which include a number of novel 4-2 and 5-2 compressor designs, are prototyped and simulated to evaluate their performance in speed, power dissipation and power-delay product. The newly developed circuits are based on various configurations of the novel 5-2 compressor architecture with the new carry generator circuit, or existing architectures configured with the proposed circuit for the exclusive OR (XOR) and exclusive NOR ( XNOR) [XOR-XNOR] module. The proposed new circuit for the XOR-XNOR module eliminates the weak logic on the internal nodes of pass transistors with a pair of feedback PMOS-NMOS transistors. Driving capability has been considered in the design as well as in the simulation setup so that these 4-2 and 5-2 compressor cells can operate reliably in any tree structured parallel multiplier at very low supply voltages. Two new simulation environments are created to ensure that the performances reflect the realistic circuit operation in the system to which these cells are integrated. Simulation results show that the 4-2 compressor with the proposed XOR-XNOR module and the new fast 5-2 compressor architecture are able to function at supply voltage as low as 0.6 V, and outperform many other architectures including the classical CMOS logic compressors and variants of compressors constructed with various combinations of recently reported superior low-power logic cells.     

基于信号处理技术的正念脑电信息提取方法

为了更好地发挥正念的应用价值,探索并揭示其作用机制已成为相关研究的重中之重。脑电信号是一种方便且非常有效的研究手段,几乎蕴藏着正念过程中心理状态变化的全部信息。结合信号处理技术,从时域、频域、时频结合以及非线性特征量等方面分析正念脑电信号在不同角度下的物理意义及应用方法,这些方法有望为挖掘正念的作用机制提供理论、技术上的支持。     

The bootstrap and its application in signal processing

The bootstrap is an attractive tool for assessing the accuracy of estimators and testing hypothesis for parameters where conventional techniques are not valid, such as in small data-sample situations. We highlight the motivations for using the bootstrap in typical signal processing applications and give several practical examples. Bootstrap methods for testing statistical hypotheses are described and we provide an analysis of the accuracy of bootstrap tests. We also discuss how the bootstrap can be used to estimate a variance-stabilizing transformation to define a pivotal statistic, and we demonstrate the use of the bootstrap for constructing confidence intervals for flight parameters in a passive acoustic emission problem     

High-speed, low-power, bipolar standard cell design methodology forGbit/s signal processing

A low-power Si bipolar standard cell LSI design methodology for gigabit/second signal processing is described. To obtain high-speed operation, it features a pair of differential clock channels inside cells, differential clock distribution with the placement of differential wires of equal length and load, a performance-driven layout, and a highly accurate static timing analysis. A computer-aided-design-based optimization technology for power dissipation makes cell currents minimum while maintaining the circuit speed. A 5.6-K gate synchronous digital hierarchy signal-processing LSI operating at 1.6 Gbit/s with only 3.9 W power consumption demonstrates the effectiveness of this design method     

Sparse FIR notch filter design and its application

A technique for designing a sparse FIR notch filter is presented. First, a sparse property of the ideal notch filter, whose notch frequency has the form (q/2p)π is derived, where p and q are coprime integers. Then, the Lagrange multiplier method is used to obtain the coefficients of the sparse notch filter which is optimal in the least-squares sense. Next, a design example is presented to demonstrate the effectiveness of this approach. Finally, a sparse notch filter is applied to eliminate the 60 Hz powerline interference superimposed on the electrocardiogram signals     

基于PSP及Kalman滤波的PCMA信号盲分离算法

提出了一种成对载波多址系统中信息序列和信道联合估计的算法。该算法在不具备任一协作通信方发送的信息序列的先验知识前提下从混合信号中解调出两路信息序列。该算法结合了逐幸存路径处理法无延迟的信道参数估计特性和Kalman滤波良好的估计性能。仿真实验表明,该算法具有良好的信道捕获与跟踪能力,且实现较好的符号序列估计性能。     

基于MSP430的低成本及超低功耗数字测温器设计

文中设计的测温装置主要是面向低成本和低功耗的应用需求,利用MSP430单片机内嵌的温度传感器以及简单的LED灯或蜂鸣器,即可实现温度数据采集和超温报警功能。特别的,针对MSP430内嵌的温度传感器所存在的精度不足问题,本文还设计了一种利用分段线性回归的方法,对MSP430内部测温模块所测得的温度数据进行补偿及纠正,得到能够满足实际需要的温度值。