n the first part of this book, we give an introduction to the basic applications of wireless com- munications, as well as the technical problems inherent in this communication paradigm. After a brief history of wireless, Chapter 1 describes the different types of wireless services, and works out their fundamental differences. The subsequent Section 1.3 looks at the same problem from a different angle: what data rates, ranges, etc., occur in practical systems, and especially, what combination of performance measures are demanded (e.g., what data rates need to be transmitted over short distances; what data rates are required over long distances?) Chapter 2 then describes the technical challenges of communicating without wires, putting special emphasis on fading and co-channel interference. Chapter 3 describes the most elementary problem of designing a wireless system, namely to set up a link budget in either a noise-limited or an interference-limited system. After studying this part of the book, the reader should have an overview of different types of wireless services, and understand the technical challenges involved in each of them. The solutions to those challenges are described in the later parts of this book.
标签： Communications Wireless Edition 2nd
上传时间： 2020-06-01
上传用户：shancjb
基于NE555设计的声音传感器模块ALTIUM硬件原理图+PCB文件，2层板设计，大小为29x30mm，Altium Designer 设计的工程文件，包括原理图及PCB文件，可以用Altium(AD)软件打开或修改，可作为你的产品设计的参考。主要器件型号列表如下：Library Component Count : 8Name Description----------------------------------------------------------------------------------------------------2N3904 NPN General Purpose AmplifierCap CapacitorComponent_1_1 Header 3H Header, 3-Pin, Right AngleLED3 Typical BLUE SiC LEDMKF 麦克风Res 电阻Res2 Resistor
上传时间： 2021-11-17
上传用户：
AT89S52-24单片机最小系统开发板ALTIUM设计硬件原理图+PCB文件,2层板设计，大小为121x149mm，Altium Designer 设计的工程文件，包括完整的原理图及PCB文件，可以用Altium(AD)软件打开或修改，可作为你的产品设计的参考。主要器件型号列表如下：Library Component Count : 14Name Description----------------------------------------------------------------------------------------------------AT89S52-P 8 位微处理器/40引脚CAP CapacitorCAPACITOR POL CapacitorCRYSTAL CrystalD Connector 9 Receptacle Assembly, 9 Position, Right AngleHeader 2 Header, 2-PinHeader 4 Header, 4-PinHeader 5X2 Header, 5-Pin, Dual rowLED MAX232PZ_9 排针——9RES2SW-DPST Double-Pole, Single-Throw SwitchSW-PB Switch
上传时间： 2021-11-17
上传用户：
AT89S52单片机主8入8出继电器工控主板ALTIUM设计硬件原理图+PCB文件,2层板设计，大小为121x149mm，Altium Designer 设计的工程文件，包括完整的原理图及PCB文件，可以用Altium(AD)软件打开或修改，可作为你的产品设计的参考。主要器件型号列表如下：Library Component Count : 25Name Description----------------------------------------------------------------------------------------------------24LC02AJKG 按键开关AT89S52-P 8 位微处理器/40引脚CAP CapacitorCAPACITOR POL CapacitorCPDR 瓷片电容CRYSTAL CrystalD Connector 9 Receptacle Assembly, 9 Position, Right AngleDG 电感DJDR 电解电容GO 光耦Header 5X2 Header, 5-Pin, Dual rowJDQYCK 继电器——1常开1常闭LED 发光二极管LM2576HVT-3.3 Simple Switcher 3A Step Down Voltage RegulatorMAX232 NPN NPN Bipolar TransistorPZ_2 排针——2PZ_3 排针——3RES2Res 电阻Res PZ_8 8位排阻SW-DPST Double-Pole, Single-Throw SwitchWY2JG 稳压二级管ZL2JG 整流二极管
上传时间： 2021-11-17
上传用户：kingwide
InGaAs/AlGaAs semiconductor lasers come in threetypes: VCSELs and two types of EELs. The VCSEL, asits name implies, emits vertically, normal to the planeof the device, owing to cavity mirrors grown withinthe epitaxial material itself. The VCSEL’s circular beamhas a numerical aperture (NA) of roughly 0.2, or a fullangle of approximately 25 degrees.
标签： tof
上传时间： 2022-02-12
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为解决移相全桥电路驱动及相角控制问题,设计了一种数字控制的移相全桥驱动电路.以TPL521为光耦隔离、IR2110为栅极驱动芯片.由DSP产生PWM信号,经过光耦隔离和逻辑电路后送至IR2110进行相角控制.文章对IR2110驱动电路原理进行分析及参数进行设计,对TMS320F28335进行设置并给出部分代码.实验结果表明：通过TMS320F28335可产生的不同相角的PWM波形,满足了移相全桥对不同相角控制的要求.In order to solve the problem of phase-shifted full-bridge circuit driving and phase angle control,a digitally controlled phaseshifted full-bridge driving circuit was designed. TPL521 optocoupler isolation,IR2110 gate driver chip. PWM signals are generated by the DSP and sent to the IR2110 for phase angle control after optocoupler isolation and logic circuits. This text carries on the analysis to the principle of IR2110 drive circuit and parameter design,set up and give out some code to TMS320F28335. The experimental results show that the PWM waveforms with different phase angles generated by TMS320F28335 can meet the requirements of phase-shifted full-bridge control for different phase angles.
上传时间： 2022-05-03
上传用户：zhanglei193
