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Four

  • UMTS+Performance+Measurement+A+Practical+Guide

    Having dealt with in-depth analysis of SS#7, GSM and GPRS networks I started to monitor UTRAN interfaces approximately Four years ago. Monitoring interfaces means decoding the data captured on the links and analysing how the different data segments and messages are related to each other. In general I wanted to trace all messages belonging to a single call to prove if the network elements and protocol entities involved worked fine or if there had been failures or if any kind of suspicious events had influenced the normal call proceeding or the call’s quality of service. Cases showing normal network behaviour have been documented in Kreher and Ruedebusch (UMTS Signaling. John Wiley & Sons, Ltd, 2005), which provides examples for technical experts investigating call flows and network procedures.

    标签: Performance Measurement Practical Guide UMTS

    上传时间: 2020-06-01

    上传用户:shancjb

  • Wireless+Communications+Algorithmic+Techniques

    Digital radios have undergone an astonishing evolution in the last century. Born as a set of simple and power-hungry electrical and electromechanical devices for low data rate transmission of telegraph data in the Marconi age, they have transformed, thanks to substantial advances in electronic technology, into a set of small, reliable and sophisticated integrated devices supporting broadband multimedia communications. This, however, would not have been possible unless significant progress had been made in recent decades in the field of signal processing algorithms for baseband and passband signals. In fact, the core of any modern digital radio consists of a set of algorithms running over programmable electronic hardware. This book stems from the research and teaching activities of its co-authors in the field of algorithmic techniques for wireless communications. A huge body of technical literature has accumulated in the last Four decades in this area, and an extensive coverage of all its important aspects in a single textbook is impossible. For this reason, we have selected a few important topics and, for ease of reading, organized them into two parts.

    标签: Communications Algorithmic Techniques Wireless

    上传时间: 2020-06-01

    上传用户:shancjb

  • DSP in Power Electronics Control Circuits

    The first edition of the book was one of the elements of my habilitation (a quali- fication above a Ph.D., which is a necessary step for obtaining the title of a professor in Poland and other European countries), and as a result it was subse- quently very carefully reviewed by Four reviewers. The habilitation was a success. Using the insightful comments from my reviewers, I have improved the current version and eliminated some typographic errors that were initially overlooked.

    标签: Electronics Circuits Control Power DSP in

    上传时间: 2020-06-07

    上传用户:shancjb

  • Field_Geophysics

    The purpose of this book is to help anyone involved in small-scale geophys- ical surveys. It is not a textbook in the traditional sense, in that it is designed for use in the field and concerns itself with practical matters – with the- ory taking second place. Where theory determines field practice, it is stated, not developed or justified. For example, no attempt is made to explain why Four-electrode resistivity works where two-electrode surveys do not.

    标签: Field_Geophysics

    上传时间: 2020-06-09

    上传用户:shancjb

  • DRM023_3-Phase AC Designer Reference Manual

    This reference design describes the design of a 3-phase AC induction vector control drive with position encoder coupled to the motor shaft. It is based on Motorola’s DSP56F805 dedicated motor control device. AC induction motors, which contain a cage, are very popular in variable speed drives. They are simple, rugged, inexpensive and available at all power ratings. Progress in the field of power electronics and microelectronics enables the application of induction motors for high-performance drives, where traditionally only DC motors were applied. Thanks to sophisticated control methods, AC induction drives offer the same control capabilities as high performance Four-quadrant DC drives.

    标签: Reference Designer Manual Phase DRM 023 AC

    上传时间: 2020-06-10

    上传用户:shancjb

  • ADC模数转换器件Altium Designer AD原理图库元件库

    ADC模数转换器件Altium Designer AD原理图库元件库SV text has been written to file : 4.4 - ADC模数转换器件.csvLibrary Component Count : 29Name                Description----------------------------------------------------------------------------------------------------ADC0800             National 8-Bit Analog to Digital ConverterADC0809             ADC0831             ADCADC0832             ADC8                Generic 8-Bit A/D ConverterCLC532              High-Speed 2:1 Analog MultiplexerCS5511              National 16-Bit Analog to Digital ConverterDAC8                Generic 8-Bit D/A ConverterEL1501              Differential line Driver/ReceiverEL2082              Current-Mode MultiplierEL4083              Current Mode Four Quadrant MultiplierEL4089              DC Restored Video AmplifierEL4094              Video Gain Control/FaderEL4095              Video Gain Contol/Fader/MultiplexerICL7106             LMC6953_NSC         PCI Local Bus Power SupervisorMAX4147             300MHz, Low-Power, High-Output-Current, Differential Line DriverMAX4158             350MHz 2-Channel Video Multiplexer-AmplifierMAX4159             350MHz 2-Channel Video Multiplexer-AmplifierMAX4258             250MHz, 2-Channel Video Multiplexer-AmplifierMAX4259             250MHz 2-Channel Video Multiplexer-AmplifierMAX951              Ultra-Low-Power, Single-Supply Op Amp + Comparator + ReferenceMAX952              Ultra-Low-Power, Single-Supply Op Amp + Comparator + ReferenceMC1496              Balanced Modulator/DemodulatorPLL100k             Generic Phase Locked LoopPLL10k              Generic Phase Locked LoopPLL5k               Generic Phase Locked LoopPLLx                Generic Phase Locked Loop水位计              

    标签: adc 模数转换 altium designer

    上传时间: 2022-03-13

    上传用户:zhengtiantong

  • 电动汽车永磁无刷直流电机控制器设计

    对某四轮独立驱动电动汽车轮毂电机进行研究,设计一种永磁无刷直流电机控制器.以STM32F103RBT6芯片为基础,对电机驱动电路、采样电路和保护电路分别进行硬件设计与分析;同时,采用模块化软件设计方案,对该控制器的软件系统进行升级.实验验证表明:所设计的电机控制器能使电机响应迅速、转速稳定、无超调,且电动车动力输出性能良好.A permanent magnet brushless direct current motor controller was designed by studying the hub motor of a Four-wheel independent drive electric vehicle.Based on STM32 F103RBT6 chip,the hardware design and analysis of motor drive circuit,sampling circuit and protection circuit were carried out respectively.At the same time,modular software design scheme was adopted to upgrade the software system of the controller.Experimental results show that the designed motor controller can ensure the motor fast response,stable speed,no overshoot,and good power output performances.

    标签: 电动汽车 永磁无刷直流电机

    上传时间: 2022-03-26

    上传用户:qingfengchizhu

  • 基于STM32的智能小车四轮驱动控制系统设计

    在传统智能小车驱动电路设计中,较多考虑使用直流电机还是步进电机,电机功率、能耗等性能参数。使用具有armCortexM4内核的STM32嵌入式平台控制四轮的4个直流电机。文章基于PWM技术及PID算法,对四轮进行精准地速度、转向及启停控制,实验表明此小车具有优越各种地形适应能力。In the traditional intelligent car drive circuit design,DC motor or stepping motor,motor power,energy consumption and other performance parameters are considered.The Four DC motors with Four wheels are controlled by STM32 embedded platform with arm Cortex M4 kernel.Based on the PWM technology and PID algorithm,the accurate ground speed,steering,and start-stop control of the Four wheels are carried out.The experiment shows that the vehicle has the superior adaptability to all kinds of terrains.

    标签: stm32 智能小车 控制系统

    上传时间: 2022-04-02

    上传用户:ibeikeleilei

  • 高精度双向DC电源电流采样电路设计

    为适应双向DC/DC功率变换的电流采样需求,一种高精度高边电流采样电路被提出。其基本思想是在功率电路的高边串入采样电阻,借助电流镜原理并引入偏置电流电路,将双向电流均转换为正向电压输出。通过理论分析与仿真结合的方法对电流镜采样原理及4种不同的偏置电流电路方案进行对比,最后通过实验数据验证了高精度高边电流采样电路的有效性。实验数据表明,该采样电路可在-25~75℃的温度工作范围内,针对-10~+10 A范围内的电流采样实现优于5%的采样精度。Current sensing plays an important role in controlling,monitoring or protection functions of power systems.To meet the current sensing requirement of bidirectional DC/DC converters,a high-accuracy bidirectional current sensing circuit is proposed.The proposed current sensing circuit inserts a resistor in the path of the current to be sensed,while the current mirror and biased current circuit are introduced.Therefore,the bidirectional current can be expressed by positive voltage.By theoretical analysis and simulation,the sampling theory is analyzed and Four biased current circuits are compared.At last,experimental results verified the proposed method.It is demonstrated that the proposed current sensing circuit can achi...

    标签: 双向DC电源 电流采样

    上传时间: 2022-04-22

    上传用户:sheng199241

  • 模型预测控制外文教程

    这是一本英文版的MPC的MATLAB教程,讲这一块的资料太少了,故上传一本。MPC is one of the few areas that has received on-going interest from researchers in both the industrial and cademic communities.Four major aspects of model predictive control make the design methodology attractive to both practitioners and academics.This is particularly attractive to industry where tight profit margins and limits on the process operation are inevitably present. The third aspect is the ability to perform on-line process optimization. The Fourth aspect  is the simplicity of the design framework in handling all these complex issues.

    标签: 模型预测控制

    上传时间: 2022-05-05

    上传用户:zhanglei193