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  • 射频集成电路设计John Rogers(Radio Freq

    Radio Frequency Integrated Circuit Design I enjoyed reading this book for a number of reasons. One reason is that itaddresses high-speed analog design in the context of microwave issues. This isan advanced-level book, which should follow courses in basic circuits andtransmission lines. Most analog integrated circuit designers in the past workedon applications at low enough frequency that microwave issues did not arise.As a consequence, they were adept at lumped parameter circuits and often notcomfortable with circuits where waves travel in space. However, in order todesign radio frequency (RF) communications integrated circuits (IC) in thegigahertz range, one must deal with transmission lines at chip interfaces andwhere interconnections on chip are far apart. Also, impedance matching isaddressed, which is a topic that arises most often in microwave circuits. In mycareer, there has been a gap in comprehension between analog low-frequencydesigners and microwave designers. Often, similar issues were dealt with in twodifferent languages. Although this book is more firmly based in lumped-elementanalog circuit design, it is nice to see that microwave knowledge is brought inwhere necessary.Too many analog circuit books in the past have concentrated first on thecircuit side rather than on basic theory behind their application in communications.The circuits usually used have evolved through experience, without asatisfying intellectual theme in describing them. Why a given circuit works bestcan be subtle, and often these circuits are chosen only through experience. Forthis reason, I am happy that the book begins first with topics that require anintellectual approach—noise, linearity and filtering, and technology issues. Iam particularly happy with how linearity is introduced (power series). In therest of the book it is then shown, with specific circuits and numerical examples,how linearity and noise issues arise.

    标签: Rogers Radio John Freq

    上传时间: 2014-12-23

    上传用户:han_zh

  • 雪崩光电二极管的偏置电压和电流检测电路

      Avalanche photodiodes (APDs) are widely utilized in laserbased fiberoptic systems to convert optical data intoelectrical form. The APD is usually packaged with a signalconditioning amplifier in a small module. An APD receivermodule and attendant circuitry appears in Figure 1. TheAPD module (figure right) contains the APD and a transimpedance(e.g., current-to-voltage) amplifier. An opticalport permits interfacing fiberoptic cable to the APD’sphotosensitive portion. The module’s compact constructionfacilitates a direct, low loss connection between theAPD and the amplifier, necessary because of the extremelyhigh speed data rates involved

    标签: 雪崩 光电二极管 偏置电压 电流检测电路

    上传时间: 2013-10-25

    上传用户:brain kung

  • 高效率,高密度,高电流应用的多相转换器

      As logic systems get larger and more complex, theirsupply current requirements continue to rise. Systemsrequiring 100A are fairly common. A high current powersupply to meet such requirements usually requires parallelingseveral power regulators to alleviate the thermalstress on the individual power components. A powersupply designer is left with the choice of how to drive theseparalleled regulators: brute-force single-phase or smartPolyPhaseTM.

    标签: 高效率 密度 多相转换器 高电流

    上传时间: 2013-10-08

    上传用户:zhqzal1014

  • 高电压,低噪音,DCDC转换器

      Photomultipliers (PMT), avalanche photodiodes (APD),ultrasonic transducers, capacitance microphones, radiationdetectors and similar devices require high voltage,low current bias. Additionally, the high voltage must bepristinely free of noise; well under a millivolt is a commonrequirement with a few hundred microvolts sometimesnecessary. Normally, switching regulator confi gurationscannot achieve this performance level without employingspecial techniques. One aid to achieving low noise is thatload currents rarely exceed 5mA. This freedom permitsoutput fi ltering methods that are usually impractical

    标签: DCDC 高电压 低噪音 转换器

    上传时间: 2013-10-28

    上传用户:lhw888

  • 基于C8051F310的山路转弯预防警示系统

    针对盘山路存在的转弯盲区,即在转弯时司机无法得知弯路对面是否有车辆通过,设计一种基于C8051F310的山路转弯预防警示系统。该系统利用一阶滤波算法检测山路转弯时是否有车辆通过。运用该算法可增强系统检测的实时性,提高检测机动车辆的灵敏度,同时大大减少环境温度对检测的干扰。试验表明该系统能够正确指示出在山路转弯时是否有车辆通过,目前该系统已安装在盘山路上,可大大减少事故的发生率。 Abstract:  Aiming at passing hilly road,there is a turn blind spot.Motormen usually do not know if the passing of vehicles pass the road.So a system of defending accident on hilly road is designed,which is based on MCU C8051F310.The sys-tem uses the first-order filter algorithm to detect whether there are passing vehicles.This algorithm enhances the real-time detection and improves the sensitivity of detection vehicles.Meanwhile,it reduces the detection interference of environmen-tal temperature.The experimental results show that this system can exactly indicate if there are passing vehicles.At present,the system has been successfully applied to hilly road.The system can greatly decrease accident.

    标签: C8051F310 转弯

    上传时间: 2013-10-10

    上传用户:归海惜雪

  • Emulating a synchronous serial

    The C500 microcontroller family usually provides only one on-chip synchronous serialchannel (SSC). If a second SSC is required, an emulation of the missing interface mayhelp to avoid an external hardware solution with additional electronic components.The solution presented in this paper and in the attached source files emulates the mostimportant SSC functions by using optimized SW routines with a performance up to 25KBaud in Slave Mode with half duplex transmission and an overhead less than 60% atSAB C513 with 12 MHz. Due to the implementation in C this performance is not the limitof the chip. A pure implementation in assembler will result in a strong reduction of theCPU load and therefore increase the maximum speed of the interface. In addition,microcontrollers like the SAB C505 will speed up the interface by a factor of two becauseof an optimized architecture compared with the SAB C513.Moreover, this solution lays stress on using as few on-chip hardware resources aspossible. A more excessive consumption of those resources will result in a highermaximum speed of the emulated interface.Due to the restricted performance of an 8 bit microcontroller a pin compatible solution isprovided only; the internal register based programming interface is replaced by a set ofsubroutine calls.The attached source files also contain a test shell, which demonstrates how to exchangeinformation between an on-chip HW-SSC and the emulated SW-SSC via 5 external wiresin different operation modes. It is based on the SAB C513 (Siemens 8 bit microcontroller).A table with load measurements is presented to give an indication for the fraction of CPUperformance required by software for emulating the SSC.

    标签: synchronous Emulating serial

    上传时间: 2014-01-31

    上传用户:z1191176801

  • 户外使用的无线蓝牙立体声音频系统

    Abstract: When people want portable music, they usually rely on battery-powered audio devices. With a bit of engineeringblood (or curiosity) running in your veins, it is not difficult to build a wireless Bluetooth® stereo audio system that can becontrolled with any device that has a Bluetooth connection and a music player

    标签: 无线蓝牙 立体声 音频系统

    上传时间: 2013-10-09

    上传用户:天空说我在

  • XAPP440 - Xilinx CPLD的上电性能

    Applying power to a standard logic chip, SRAM, or EPROM, usually results in output pinstracking the applied voltage as it rises. Programmable logic attempts to emulate that behavior,but physics forbids perfect emulation, due to the device programmability. It requires care tospecify the pin behavior, because programmable parts encounter unknown variables – yourdesign and your power environment.

    标签: Xilinx XAPP CPLD 440

    上传时间: 2013-11-24

    上传用户:253189838

  • Knowledge of the process noise covariance matrix is essential for the application of Kalman filteri

    Knowledge of the process noise covariance matrix is essential for the application of Kalman filtering. However, it is usually a difficult task to obtain an explicit expression of for large time varying systems. This paper looks at an adaptive Kalman filter method for dynamic harmonic state estimation and harmonic injection tracking.

    标签: application covariance Knowledge essential

    上传时间: 2014-01-19

    上传用户:litianchu

  • This paper deals with the problem of speech enhancement when a corrupted speech signal with an addi

    This paper deals with the problem of speech enhancement when a corrupted speech signal with an additive colored noise is the only information available for processing. Kalman filtering is known as an effective speech enhancement technique, in which speech signal is usually modeled as autoregressive (AR) process and represented in the state-space domain.

    标签: speech with enhancement corrupted

    上传时间: 2015-09-07

    上传用户:zhangyi99104144