高精度分段线性补偿基准电压源

介绍了一种新型电压基准电路,基于分段线性补偿方式设计了一种高精度基准电压源.利用与温度成正比的电流(IPTAT)和与温度成反比的电流(ICTAT)做差,从而获得用于基准电压源曲率补偿的分段线性电流.将电路整个工作温度区间分为两段,利用分段线性电流完成补偿,且增加三极管基极电流补偿技术,最终得到高精度的基准输出电压.仿真...     

一种二阶补偿带隙基准设计

基于分段补偿原理和MOS管的漏极电流是过驱动电压的平方关系函数,提出了一种新颖的二阶补偿结构,仅引入一股与温度成平方关系的电流,既补偿了低温阶段的基准电压,又补偿了高温阶段的基准电压,大大提高了基准电压源随温度变化的稳定性。采用0.5μm BCD工艺对电路进行仿真,结果表明,输出电压为1.24 V,温度范围在-35℃～135℃时,温度系数为2.82 ppm/℃;在低频时,电源抑制比达到了75.6 dB。     

一种结构简单的CMOS带隙基准电压源设计

本文提出了一种结构简单高电源抑制比的CMOS带隙基准电压源,供电电源3.3V.采用CSMC 0.5um CMOS工艺.Spectre仿真结果表明,基准输出电压在温度为-40～+80℃时,温度系数为45.53×10-6/℃,输出电压在电源电压为2～5V范围内变化小.电源抑制比达到-73.3dB.     

一种二阶温度补偿的CMOS带隙基准电路

提出了一种可用于标准CMOS工艺下且具有二阶温度补偿电路的带隙基准源。所采用的PTAT2电流电路是利用了饱和区MOSFET的电流特性产生的,具有完全可以与标准CMOS工艺兼容的优点。针对在该工艺和电源电压下传统的启动电路难以启动的问题,引入了一个电阻,使其可以正常启动。基准核心电路中的共源共栅结构和串联BJT管有效地提高了电源抑制比,降低了温度系数。基于TSMC 0.35μm CMOS工艺运用HSPICE软件进行了仿真验证。仿真结果表明,在3.3V供电电压下,输出基准电压为1.2254V,温度系数为2.91×10-6V/℃,低频的电源抑制比高达96dB,启动时间为7μs。     

一种高精度双极性带隙基准电压源的设计破

本文提出了一种基于双极性工艺的高性能带隙基准电压源的设计。该电路结构简单,性能优异。用Spectre进行仿真,结果表明,在-50～90℃的温度范围内,其温度系数为5.7ppm/℃;在3～15V的电源电压内,电源线性调整率为1.0mv/V,电源抑制比(PSRR)为-55dB。     

一种低压低温漂的CMOS带隙基准源

基于标准0.35umCMOS工艺,采用一级温度补偿电压作为温度曲率校正电压,与传统采用PTAT电压作为温度曲率校正电压相比,获得了一个电路结构简单,性能更好的带隙基准源。使用Hspice进行仿真,仿真结果表明电路可以在-20-100℃范围内,平均温度系数约2ppm/℃,工作电压为1V左右,获得了一个高性能的带隙基准电压源。该带隙基准源可应用于高精度模数转换器(ADC)、数模转换器(DAC)和系统集成芯片(SOC)中。     

一种采用曲率补偿技术的高精度带隙基准电压源的设计

本文设计了采用曲率补偿．具有较高的温度稳定性的高精度带隙基准电压源。设计中没有使用运算放大器．电路结构简单，且避免运算放大嚣所带来的高失调和必须补偿的缺陷。此外电路又采用了内部负反馈回路．使基准电压源工作一个稳定的电压下．从而提高基准电压源的电源抑制比(PSRR)。文中最后给出了此基准电压源的各种性能的仿真波形。     

一种新颖的低电压CMOS带隙基准源设计

设计一种新颖的低电压CMOS带隙基准电压源电路.电路采用了适合低电源电压工作的nMOS输入对管折叠共源共栅运算放大器,并提出一种新颖的启动电路.基于SMICO.35μm标准CMOS工艺,Cadence Spectre仿真结果表明:在低于1-V的电源电压下,所设计的电路能稳定工作,输出稳定的基准电压为622mV,最低电源电压为760mV.不高于100KHz的频率范围内,电源噪声抑制比为-75dB.在-20℃到100℃范围内,温度系数20ppm/℃.     

一种高精度高电源抑制的CMOS带隙基准

本文介绍了一种高精度高电源抑制的CMOS带隙电压基准,电源电压3V.该电路的实现是基于0.6um 5V的CMOS工艺.为了达到较高的精度和电源抑制比,电路中采用了一个PMOS电流源做调整管,以保证基准核的电流恒定.仿真结果表明,该基准电路在低频下的电源抑制比可达到-88dB,温度变化范围从-40℃至120℃.时,温度系数只有3.5ppm,输出电压误差为0.65mV.     

电流模式的高阶曲率补偿CMOS带隙基准源

因为传统的带隙电压基准源只经过了一阶温度补偿,且输出电压只能在1.2 V左右,所以为了得到一个可调的、更高精度的电压基准源,提出了电流模式的带隙电压基准源电路。电路采用了高阶曲率补偿方法,且输出的基准电压可根据输出电阻的大小进行调节。电路采用gpdk090 CMOS工艺,通过Spectre仿真,当电源电压为3.6 V、在-60℃~-120℃温度范围内、温度系数为14.4×10-6/℃时电源电压抑制比为78.3 d B,输出电压平均为1.162 V。     

An improved method for independent component analysis with reference

Through incorporating a priori information available in some applications for independent component analysis (ICA) as the reference into the negentropy contrast function for FastICA, ICA with reference (ICA-R) or constrained ICA (cICA) is obtained as a constrained optimization problem. ICA-R achieves some advantages over earlier methods, whereas its computation load is somewhat high and its performance is strongly dependent on the threshold parameter. By alternately optimizing the negentropy contrast function for FastICA and the closeness measure for ICA-R, an improved method for ICA-R is proposed in this paper which can avoid the inherent drawbacks of ICA-R. The validity of the proposed method is demonstrated by simulation experiments.     

改进的IMU传感器安装误差正交补偿方法

针对传统的正交补偿方法难以保证惯性测量单元具有较高的正交补偿精度的问题,提出了一种改进的适用于大角度和小角度安装误差角情形的正交补偿方法,该方法分别建立三轴加速度计和三轴光纤陀螺传感器的安装误差方程,对惯性测量单元进行速率标定和多位置静态标定,并利用最小二乘法求解惯性测量单元的安装误差方程参数.仿真和实验结果表明:该方法较传统的正交补偿方法具有较高的正交补偿精度和传感器标定精度,且回避了静态标定时在较大安装误差角下利用转位机构获得零偏存在较大误差的问题,大大地提高了标定效率.     

An improved motion compensation method for high resolution UAV SAR imaging

The polynomial and sinusoidal motion errors always exist in the unmanned aero vehicle （UAV） SAR due to the small size and low velocity of the platform, causing serious spectrum compressing/stretching and significant spectral replicas of the azimuth signal. The motion errors induce serious blurring of the SAR image and ＂ghost targets＂, and can hardly be precisely estimated by the conventional motion compensation （MOCO） method. In this paper, an improved MOCO method is proposed to estimate and eliminate the motion errors in the high resolution UAV SAR without high precision inertial navigation system （INS） data. The time domain range walk correction （RWC） operation in the coarse phase error estimation process of the proposed MOCO method is the key operation that ensures the estimation accuracy of the whole MOCO method. Finally, the validity of the improved MOCO method is verified by computer simulations and real UAV SAR data processing.     

An improved parameter identification approach for piecewise affine model

This study proposes a high-efficient approach to identify the piecewise affine (PWA) model. The proposed approach constitutes two major steps, initial estimation and refinement process. In the initial estimation, Hough Transform (HT) is adopted to generate a group of submodel candidates; then a variable-threshold technique is applied to pick up the real submodel. In the refinement process, not only the distance constraint between data points and submodel's hyperplanes but also the clustering constraint between data points in regression regions are considered. An efficient algorithm is presented to alternately refine the submodel's parameters and the subregression sets. In the case study, the proposed approach is used to identify the fault model of the track circuit in high-speed railway. Analysis shows that the proposed approach has linear time complexity and exhibits superior data availability in small-sample case.     

改进的超越函数分段线性逼近方法

针对超越函数计算中所采用的分段线性逼近算法存在的无法提前确定精度及部分区间资源浪费的问题,提出一种改进的分段线性逼近超越函数算法。该算法由预定义的逼近区间端点计算出用于逼近的线性函数,根据被逼近函数的凹凸性对所计算线性函数进行调整,在此基础上计算出预定义逼近区间内调整后函数与被逼近函数之间的最大误差;按照所需精度的要求,自动调整逼近区间,通过该过程的迭代,获得了较少分段次数。算法结果在Matlab上进行仿真,仿真结果表明,所提算法的分段数相比等分法减少了60%。所提算法在保证精度的前提下,降低了查找表（LUT）的资源消耗。     

An off‐line design method of compensation law for constrained linear systems

This paper deals with a design method of compensation law for linear constrained systems. By employing singular value decomposition of linear systems, we provide a design method of compensation law which fulfils system constraints. The feature of resulting compensation law is illustrated with numerical examples. Copyright © 2007 John Wiley & Sons, Ltd.     

Model reference adaptive control of discrete‐time piecewise linear systems

This article presents a switched model reference adaptive controller for discrete‐time piecewise linear systems. In the spirit of the work by Landau in the late seventies, proof of asymptotic stability of the closed‐loop error system is obtained, recasting its dynamics as a feedback system and showing the feedforward and the feedback paths are both passive. The challenge is that both paths can be piecewise linear. Numerical results show excellent performance of the proposed controller even in the face of sudden variations of the plant parameters. Copyright © 2012 John Wiley & Sons, Ltd.     

An improved robust stability and robust stabilization method for linear discrete-time uncertain systems

This paper addresses the problems of the robust stability and robust stabilization of a discrete-time system with polytopic uncertainties. A new and simple method is presented to directly decouple the Lyapunov matrix and the system dynamic matrix. Combining this method with the parameter-dependent Lyapunov function approach yields new criteria that include some existing ones as special cases. A numerical example illustrates the improvement over the existing ones.