基于FFT的放大器非线性失真研究装置

阐述MCU STM32F407为核心的单片机作为微控制器,运用FFT算法处理采集到的数据,计算出总谐波失真（THD）,完成对输出波形THD的高精度测量,用显示屏实现了波形及幅频特性的显示。     

基于STM32的非线性失真放大器设计与测试分析

非线性失真放大器装置主要由晶体管、模拟开关等元器件所构成的非线性失真信号发生放大器和基于STM32的总谐波失真度测量仪组成,可以用于产生在模拟电子电路中常见的4种非线性失真信号,即顶部、底部、双向和交越失真信号,测试仪可以用于对上述4种非线性失真信号进行总谐波失真度的测量.在软硬联调测试中,该非线性失真放大器装置可以输...     

降低行波管放大器非线性的预失真技术研究

文章提出了一种新型的利用预失真技术设计行波管配用线性化器的数学模型.在saleh提出的行波管的模型的基础上,得出了预失真电路的功率转移特性曲线和相位漂移曲线,扩展了行波管放大器的线性工作区,并实现了级联后的整个系统在线性工作区域内增益不变和零相位漂移,所得结果为行波管预失真电路的设计提供了重要的理论依据.     

放大器非线性失真对电缆电视系统的影响

本文详强地分析了放大器非线性失真的主要参数－交扰调制比，二阶、三阶载波互调经的物理意义和计算公式，并由此推导出电缆电视系统的设计方法。另外，本文还讨论了西德ＤＩＮ４５００４测试法。     

浅谈线性放大器的非线性失真

众所周知,现代音频放大器主要分为模拟放大器和数字（D类）放大器。前者又叫直线性放大器,或简称线性放大器。它的特点是放大器的输出信号Y与输入信号X的关系成正比。     

改善放大器非线性失真的各种技术

本文介绍了改善放大器非线性失真指标的各种技术，包括功率回退、预失真、前馈和砷化镓等。指出了各种技术的应用场合。     

三极管非线性放大失真特性研究

本系统依据三极管的工作特性,借助了可调电阻和模拟开关的结合,设计了一种三极管非线性放大失真研究装置.利用了STM32单片机的编程与数据处理能力,完成了对电路的控制和数据分析.研究了三极管放大电路多种失真的现象,分析每种失真的原因和正常放大的条件,实现了控制、测量、分析的一体化,并将失真波形与其THD值直观地展示.该装置...     

放大器非线性失真与最大输出电平的修正

通常人们在计算放大器非线性失真参数时 ,往往忽视了一个实际问题 ,就是对计算结果的修正。比如在计算单个放大器组合交调比时 ,使用公式 :ＣＭ =ＣＭｏ+ 2 (Ｓｏｂ-Ｓｏ) (1)计算多台相同“干放”级联的干线组合交调比时使用公式 :ＣＭｎ =ＣＭｏ+ 2 (Ｓｏｂ-Ｓｏ) - 2 0ｌｇｎ (2 )(1)和 (2 )式中 ,Ｓｏｂ为放大器标称输出电平 ;Ｓｏ 为放大器实际输出电平 ;ＣＭｏ 为放大器在标称输出电平和标称频道时的组合交调比 (标称组合交调比 ) ;ｎ为“干放”级联数。又比如在计算单个放大器组合三次差拍比时 ,使用公式 :ＣＴＢ =ＣＴＢｏ+ 2 (Ｓｏ…     

基于STM32的USB HOST实现

随着USB OTG规范的发布,USB设备大量应用于消费电子产品和通信电子产品,嵌入式设备爆炸式增长。基于嵌入式芯片的USB OTG能很好的解决两个USB设备之间的数据交换。使用STM32F407自带的USB OTG模块实现与USB设备的数据交换。     

基于STM32的简单旋转倒立摆

本设计主要研究旋转倒立摆如何实现,采用了STM32F407为控制核心板,通过对于旋转倒立摆的模型分析,采用位置式PID控制算法来优化各个控制参数能达到更好的效果。经过多次测试之后,证明系统基本实现了题目的要求。此篇报告主要总结了对于该题目的前期准备工作,对题目的任务要求进行了分析,对于设计的方案进行了选择和论证,以及从各模块功能到系统实现的理论方法对整个设计进行了系统的分析。     

基于STM32F407的颈部姿态报警装置设计

文章介绍了一种颈部姿态报警装置的设计方案。该装置以STM32F407作为主控芯片,选用6轴运动处理传感器MPU-6050获取姿态,实现了对人体颈部姿态的读取,坐姿的实时监控和报警,并语音提示当前的状态和提醒休息时间。实验证明该装置使用方便,检测灵敏,效果良好。     

基于STM32的参数可调PWM波形发生器设计

介绍了一种基于STM32的双通道参数可调PWM波形发生器的设计方法。该系统主要由PC机、STM32处理器、USB转串口模块以及光电隔离模块构成。参数可调的功能由基于LabVIEW的GUI软件实现,通过给STM32最小系统发送数据,来控制输出PWM波形的各个参数。在PC机上利用LabVIEW的GUI软件对PWM波形发生器进行测试,实测结果表明:基于STM32F407的PWM波形发生器设计方案是可行的,测量结果能够满足系统设计需求,且可以通过GUI软件进行实时查询。     

基于Cortex-M4处理器的带振动监测的直流电机控制系统设计

文章叙述了一种基于Cortex—M4处理器的带振动监测的直流电机控制系统的软硬件设计。该系统以Cortex．M4处理器内核的STM32F407为主控芯片,电机驱动电路采用高效的4NMOS驱动方案,转速反馈采用光电编码器,附加陀螺仪传感器监测电机振动,软件上采用PID算法进行精确转速控制。系统控制精确,误差为1r／min,且反应迅速,速度改变平滑,有振动保护功能,有较高的实用性。     

工厂仓库火灾预警系统的设计

针对当前工厂仓库火灾事故频繁发生,设计了一种工厂仓库火灾预警系统。该系统由火灾检测模块与中心接收模块组成,火灾检测模块利用以STM32为控制核心的智能小车在工厂仓库"巡逻",通过加装OV7670图像传感器检测火焰,一旦发现火灾事故发生,立即无线发送预警信息,信息由中心接收模块接收后通过RS 232串口传送给PC机,PC机采取相应救灾措施。实际测试表明,本系统发出预警信息的成功率高,近100%,零误判,时间短。     

FFT算法在微控制器上的设计与实现

文中描述了一种针对快速傅里叶变换(FFT)嵌入式运算系统的设计,基于ST公司ARM架构的微控制器STM32F4,该控制器拥有强大的数据运算处理能力,在硬件架构以及数据、信号处理上做出了独特的设计。着重介绍了基于Cortex-M4的FFT软件实现,应用,以及数据采样,运算等一系列问题,最后明确了下一步的研究方向。     

Wi-Fi通信模块设计

设计的Wi-Fi通信模块,可以实现Wi-Fi和USB的双向传输。该Wi-Fi模块的设计分为硬件和软件设计两部分,硬件设计主要包含基于STM32F407的最小系统模块和基于ESP8266的Wi-Fi子模块。软件设计包括基于LabVIEW的GUI软件设计和ARM处理器的程序编写。测试表明:该系统可以完成数据的无损传输,并达到设计的预定功能。     

一种可用于非线性码译码神经网络模型研究

本文提出一种非线性码神经网络译码方案,在纠错能力范围内对满足码距特性的一般非线性码以零错误概率进行纠错译码,并在检错能力范围内检错。文中具体描述了神经网络模型构造、学习算法及其理论依据。最后通过非线性等重码的译码实例表明此方案的有效性及理论和应用价值。     

Techniques for evaluating harmonic distortion in class-AB output stages: A tutorial

In this paper, we discuss and provide a detailed tutorial of four different methods for analytically evaluating the harmonic distortion in class-AB stages. All the methods are suitable for pencil-and-paper analysis and are based on modeling the stage with a specific non-linear function. We analyze them in details and extend some of them for predicting harmonic distortion behavior in a wide range of input signal amplitude. Comparisons made by means of simulations, reveal that some methods are more precise than others but require more computational effort. On the contrary, some of them are simple to use but are less precise. Moreover, some are more appropriate for predicting HD₂ and others for HD₃, only. Results of the present paper may be used by designers to choose the more efficient method for analyzing distortion in class-AB stages. Gianluca Giustolisi was born in Catania, Italy, in 1971. He received the Laurea degree (cum laude) in electronic engineering and the Ph.D. degree in electrical engineering from University of Catania, Catania, Italy, in 1995 and 1999, respectively. Currently he is associate professor at Dipartimento di Ingegneria Elettrica Elettronica e dei Sistemi (DIEES), University of Catania. His research interests include analysis, modelling and design of analog integrated circuits and systems with particular emphasis on non-linear and low-voltage applications. Gianluca Giustolisi is IEEE Member. Gaetano Palumbo was born in Catania, Italy, in 1964. He received the laurea degree in Electrical Engineering in 1988 and a Ph.D. degree from the University of Catania in 1993. Since 1993 he conducts courses on Electronic Devices, Electronics for Digital Systems and basic Electronics. In 1994 he joined the DEES (Dipartimento Elettrico Elettronico e Sistemistico), now DIEES (Dipartimento di Ingegneria Elettrica Elettronica e dei Sistemi), at the University of Catania as a researcher, subsequently becoming associate professor in 1998. Since 2000 he is a full professor in the same department. His primary research interest has been analog circuits with particular emphasis on feedback circuits, compensation techniques, current-mode approach, low-voltage circuits. Then, his research has also embraced digital circuits with emphasis on bipolar and MOS current-mode digital circuits, adiabatic circuits, and high-performance building blocks focused on achieving optimum speed within the constraint of low power operation. In all these fields he is developing some the research activities in collaboration with STMicroelectronics of Catania. He was the co-author of three books “CMOS Current Amplifiers” and ”Feedback Amplifiers: theory and design” and “Model and Design of Bipolar and MOS Current-Mode Logic (CML, ECL and SCL Digital Circuits)” all by Kluwer Academic Publishers, in 1999, 2001 and 2004, respectively. He is a contributor to the Wiley Encyclopedia of Electrical and Electronics Engineering. He is the author of more than 250 scientific papers on referred international journals (over 100) and in conferences. Moreover he is co-author of several patents. In 1999/2001 and 2004/2005 he served as Associated Editor of the IEEE Transactions on Circuits and Systems part I for the topic “Analog Circuits and Filters” and “Digital Circuits and Systems”, respectively. In 2005 he was one of the 12 panelists in the scientific-disciplinare area 09 - industrial and information engineering of the CIVR (Committee for Evaluation of Italian Research), which has the aim to evaluate the Italian research in the above area for the period 2001–2003. In 2003 he received the Darlington award. Since 2006 he is serving as Associated Editor of the IEEE Transactions on Circuits and Systems part I. Prof. Palumbo is an IEEE Senior Member.