二十世纪八十年代以来, 微带介质天线由于具有重量轻、尺寸小、良好的共形特性及较低的性能价格比等优点而引起工程技术部门的高度重视。现美国和加拿大都把微带天线用于星载合成孔径雷达以实现地面侦察和地形勘察, 日本也将微带介质天线普遍用于卫星直播电视接收系统。我国正在开发和研制新型的微带介质天线, 但这些大多在1GHz~50GHz 频段范围内进行, 且天线为窄带, 这是介质衬底微带天线的一大特点。至今, 由于天线的尺寸过大, 在VHF/ U HF 频段, 圆形或矩形微带介质天线尚未推广应用。
上传时间: 2014-12-30
上传用户:13162218709
基于大型车辆车身长、倒车有盲区的特点,提出了一种部署简便的、基于无线射频信号传输方式的智能辅助倒车系统。简要介绍了超声波测距原理和本系统设计方案,采用温度补偿方法消除温度对超声波测距精度的影响,采用433 MHz无线射频通信减少雷达主机与显示器之间布线的不便。本方案实施方便、可靠、实用性强,可在半挂车、挂车、重型载货汽车和大型客车等不便于布线的车辆上应用推广,特别适合于车辆辅助倒车系统的后装市场。
上传时间: 2013-10-13
上传用户:leesuper
第一章 微波集成电路传输线 第二章 微波集成电路的主要元件 第三章 微波集成电路的贴氧体器件 第四章 微波集成电路的滤波器 第五章 阻抗变换器、耦合器和功率分配器 第六章 微波集成的噪声放大器 第七章 微波集成变频器 第八章 集成微波固态源 第九章 微波集成控制电路
上传时间: 2013-11-07
上传用户:jiwy
本文基于多端口网络模型、腔模理论和分片法, 首次给出串行角馈微带天线输入阻抗的一种有效的理论分析方法, 导出其闭合表达式。实验结果验证了理论的正确性。采用本方法计算方便, 适于工程应用。
上传时间: 2013-11-05
上传用户:YKLMC
微波固态电路设计(第2版)
标签: 固态电路
上传时间: 2014-12-30
上传用户:旗鱼旗鱼
The main objective of this book is to present all the relevant informationrequired for RF and micro-wave power amplifier design includingwell-known and novel theoretical approaches and practical design techniquesas well as to suggest optimum design approaches effectively combininganalytical calculations and computer-aided design. This bookcan also be very useful for lecturing to promote the analytical way ofthinking with practical verification by making a bridge between theoryand practice of RF and microwave engineering. As it often happens, anew result is the well-forgotten old one. Therefore, the demonstrationof not only new results based on new technologies or circuit schematicsis given, but some sufficiently old ideas or approaches are also introduced,that could be very useful in modern practice or could contributeto appearance of new ideas or schematic techniques.
标签: Amplifier Microwave Design Power
上传时间: 2013-12-22
上传用户:vodssv
When I started writing the first edition of RF Power Amplifiers for Wireless Communications,some time back in 1997, it seemed that I was roaming a largely uninhabitedlandscape. For reasons still not clear to me there were few, if any, otherbooks dedicated to the subject of RF power amplifiers. Right at the same time, however,hundreds of engineers were being assigned projects to design PAs for wirelesscommunications products. It was not, therefore, especially difficult to be successfulwith a book that was fortuitously at the right place and the right time.
标签: Communications Amplifiers Wireless Edition
上传时间: 2013-11-12
上传用户:YYRR
双频带印刷振子天线选择双T单极天线作为模型,将其极化分集到规定大小的FR_4的介质板上;通过HFSS仿真分析对分集后两个天线之间的影响,天线顶端水平带加载螺旋线对5GHz频带的影响等方面进行了研究。
上传时间: 2013-10-20
上传用户:fredguo
RF circuit design theory and application(射频电路设计)
标签: application circuit design theory
上传时间: 2014-12-30
上传用户:aeiouetla
NNS-701 是專為移動裝置設計的全功能NFC (Near Field Communication)控制器芯片。
上传时间: 2013-10-11
上传用户:蠢蠢66