射频
上传时间： 2014-12-07
上传用户：chenbhdt
LTE基站误码率测试是基站射频测试中最为关键的测试项目之一，提出一种快速、高效的测试方法和测试架构。该方案采用基站射频板作为数据采集卡、完成上行链路的解调和模拟信号转换成I/Q数据功能，利用ADS、MATLAB搭建上行信道的同步、解码功能。测试表明该方案的测试精度达到 0.2dB，完全满足研发和生产中测试上行相关射频指标的功能需求， 同时本设计还具有开发周期短、投资成本低，操作简便、很强的跨系统移植能力。
上传时间： 2013-11-17
上传用户：xhwst
Abstract: This application note describes system-level characterization and modeling techniques for radio frequency (RF) and microwavesubsystem components. It illustrates their use in a mixed-signal, mixed-mode system-level simulation. The simulation uses an RF transmitterwith digital predistortion (DPD) as an example system. Details of this complex system and performance data are presented.
上传时间： 2013-12-18
上传用户：onewq
为了实现对矿山生产过程中三维定位和灾害预警监测，设计了一种基于RFID和无线传感的矿山实时定位预警系统，硬件包括无线射频标识模块、实时三维定位模块、监测数据采集与分析模块、灾害预警模块、灾害分析模块和地面远程控制主机。实际应用表明，该系统平台铺设灵活性强，监控范围广泛，可以三维全方位监控，有效提高矿山安全监测效率。
上传时间： 2013-11-23
上传用户：363186
采用RFID（射频识别）芯片IA4420设计了一款主动式应答器，主要应用于矿井安全生产管理。其工作中心频率为905 MHz，数据通信的核心部分是印刷偶极子天线，从仿真结果来看：其相对带宽约为40%，增益约为4.236 dB，输入阻抗接近纯电阻 50 Ω，性能参数较好。
上传时间： 2013-11-12
上传用户：caiguoqing
Radio frequency (RF) can be a complex subject to navigate, but it does not have to be. If you are just getting started with radios or maybe you cannot find that old reference book about antenna aperture, this guide can help. It is intended to provide a basic understanding of RF technology, as well act as a quick reference for those who “know their stuff” but may be looking to brush up on that one niche term that they never quite understood. This document is also a useful reference for Maxim’s products and data sheets, an index to deeper analysis found in our application notes, and a general reference for all things RF.
上传时间： 2013-10-23
上传用户：685
Abstract: This application note illustrates the flexibility of the MAX7060 ASK/FSK transmitter. While the currently available evaluationkit (EV kit) has been optimized for the device's use in a specific frequency band (i.e., 288MHz to 390MHz), this document addresseshow the EV kit circuitry can be modified for improved operation at 433.92MHz, a frequency commonly used in Europe. Twoalternative match and filter configurations are presented: one for optimizing drain efficiency, the other for achieving higher transmitpower. Features and capabilities of earlier Maxim industrial, scientific, and medical radio-frequency (ISM-RF) transmitters areprovided, allowing comparison of the MAX7060 to its predecessors. Several design guidelines and cautions for using the MAX7060are discussed.
上传时间： 2013-11-14
上传用户：swaylong
在3.84 Mcps条件下，考虑到处理增益后，满足灵敏度要求所允许的总噪声。这个总噪声包括输入热噪声kTB和系统引入的噪声NF。
上传时间： 2013-12-29
上传用户：妄想演绎师
为了实现嵌入式手持终端系统的功耗低、体积小、性能稳定的需求，以TI公司的MSP430F449的16位低功耗微控制器为中央处理单元，Semtech公司的SX1233为射频收发单元，设计了一种能广泛应用于餐饮、物流、无线抄表等领域的低成本、超低功耗的无线手持终端设备。分析了系统的功耗和编程特点，给出了系统软件的设计方案。实测结果表明，所设计的无线手持终端设备性能稳定、灵活可调，达到了设计要求。
上传时间： 2013-10-18
上传用户：SimonQQ
为满足无线网络技术具有低功耗、节点体积小、网络容量大、网络传输可靠等技术要求，设计了一种以MSP430单片机和CC2420射频收发器组成的无线传感节点。通过分析其节点组成，提出了ZigBee技术中的几种网络拓扑形式，并研究了ZigBee路由算法。针对不同的传输要求形式选用不同的网络拓扑形式可以尽大可能地减少系统成本。同时针对不同网络选用正确的ZigBee路由算法有效地减少了网络能量消耗，提高了系统的可靠性。应用试验表明，采用ZigBee方式通信可以提高传输速率且覆盖范围大，与传统的有线通信方式相比可以节约40%左右的成本。 Abstract: To improve the proposed technical requirements such as low-ower， small nodes， large capacity and reliable network transmission， wireless sensor nodes based on MSP430 MCU and CC2420 RF transceiver were designed. This paper provided network topology of ZigBee technology by analysing the component of the nodes and researched ZigBee routing algorithm. Aiming at different requirements of transmission mode to choose the different network topologies form can most likely reduce the system cost. And aiming at different network to choose the correct ZigBee routing algorithm can effectively reduced the network energy consumption and improved the reliability of the system. Results show that the communication which used ZigBee mode can improve the transmission rate， cover more area and reduce 40% cost compared with traditional wired communications mode.
上传时间： 2013-10-09
上传用户：robter
