同步技术是跳频通信系统的关键技术之一，尤其是在快速跳频通信系统中，常规跳频通信通过同步字头携带相关码的方法来实现同步，但对于快跳频来说，由于是一跳或者多跳传输一个调制符号，难以携带相关码。对此引入双跳频图案方法，提出了一种适用于快速跳频通信系统的同步方案。采用短码携带同步信息，克服了快速跳频难以携带相关码的困难。分析了同步性能，仿真结果表明该方案同步时间短、虚警概率低、捕获概率高，同步性能可靠。 Abstract: Synchronization is one of the key techniques to frequency-hopping communication system， especially in the fast frequency hopping communication system. In conventional frequency hopping communication systems， synchronization can be achieved by synchronization-head which can be used to carry the synchronization information， but for the fast frequency hopping， Because modulation symbol is transmitted by per hop or multi-hop， it is difficult to carry the correlation code. For the limitation of fast frequency hopping in carrying correlation code， a fast frequency-hopping synchronization scheme with two hopping patterns is proposed. The synchronization information is carried by short code， which overcomes the difficulty of correlation code transmission in fast frequency-hopping. The performance of the scheme is analyzed， and simulation results show that the scheme has the advantages of shorter synchronization time， lower probability of false alarm， higher probability of capture and more reliable of synchronization.
上传时间： 2013-11-23
上传用户：mpquest
The LTC®3207/LTC3207-1 is a 600mA LED/Camera driverwhich illuminates 12 Universal LEDs (ULEDs) and onecamera fl ash LED. The ULEDs are considered universalbecause they may be individually turned on or off, setin general purpose output (GPO) mode, set to blink at aselected on-time and period, or gradate on and off at aselected gradation rate. This device also has an externalenable (ENU) pin that may be used to blink, gradate, orturn on/off the LEDs without using the I2C bus. This may beuseful if the microprocessor is in sleep or standby mode. Ifused properly, these features may save valuable memoryspace, programming time, and reduce the I2C traffi c.
上传时间： 2014-01-04
上传用户：LANCE
The NXP LPC315x combine an 180 MHz ARM926EJ-S CPU core, High-speed USB 2.0OTG, 192 KB SRAM, NAND flash controller, flexible external bus interface, an integratedaudio codec, Li-ion charger, Real-Time Clock (RTC), and a myriad of serial and parallelinterfaces in a single chip targeted at consumer, industrial, medical, and communicationmarkets. To optimize system power consumption, the LPC315x have multiple powerdomains and a very flexible Clock Generation Unit (CGU) that provides dynamic clockgating and scaling.The LPC315x is implemented as multi-chip module with two side-by-side dies, one fordigital fuctions and one for analog functions, which include a Power Supply Unit (PSU),audio codec, RTC, and Li-ion battery charger.
上传时间： 2014-01-17
上传用户：Altman
解压密码：www.elecfans.com 随着微电子技术的迅速发展以及集成电路规模不断提高，对电路性能的设计 要求越来越严格，这势必对用于大规模集成电路设计的EDA 工具提出越来越高的 要求。自1972 年美国加利福尼亚大学柏克莱分校电机工程和计算机科学系开发 的用于集成电路性能分析的电路模拟程序SPICE（Simulation Program with IC Emphasis）诞生以来，为适应现代微电子工业的发展，各种用于集成电路设计的 电路模拟分析工具不断涌现。HSPICE 是Meta-Software 公司为集成电路设计中 的稳态分析，瞬态分析和频域分析等电路性能的模拟分析而开发的一个商业化通 用电路模拟程序，它在柏克莱的SPICE（1972 年推出），MicroSim公司的PSPICE （1984 年推出）以及其它电路分析软件的基础上，又加入了一些新的功能，经 过不断的改进，目前已被许多公司、大学和研究开发机构广泛应用。HSPICE 可 与许多主要的EDA 设计工具，诸如Candence,Workview 等兼容，能提供许多重要 的针对集成电路性能的电路仿真和设计结果。采用HSPICE 软件可以在直流到高 于100MHz 的微波频率范围内对电路作精确的仿真、分析和优化。在实际应用中， HSPICE能提供关键性的电路模拟和设计方案，并且应用HSPICE进行电路模拟时， 其电路规模仅取决于用户计算机的实际存储器容量。 The HSPICE Integrator Program enables qualified EDA vendors to integrate their products with the de facto standard HSPICE simulator, HSPICE RF simulator, and WaveView Analyzer™. In addition, qualified HSPICE Integrator Program members have access to HSPICE integrator application programming interfaces (APIs). Collaboration between HSPICE Integrator Program members will enable customers to achieve more thorough design verification in a shorter period of time from the improvements offered by inter-company EDA design solutions.
上传时间： 2013-11-10
上传用户：123312
MOTION BUILDER Ver.2 是用于监控 KV-H20/H20S/H40S/H20G 的参数设定以及当前动作状态的软件。 在 PC 上可以设定复杂的参数，并可以在显示画面上监控正在运行的 KV-H20/H20S/H40S/H20G。 关于 MOTION BUILDER Ver.2 概要、功能与使用方法的详细说明。在安装之前，请仔细阅读本手册，并充分 理解。 注意 1、使用 MOTION BUILDER Ver.2 时，必须在可以使用 KV-H20/H20S/H40S/H20G 上 连接的紧急停止开关的地方使用。 通讯异常时，不接受 MOTION BUILDER Ver.2 的“强制停止”，可能会导致事故指示发生。发生通信异常时，MOTION BUILDER Ver.2 的“强制停止”按钮将不起作用。 2、JOG 过程中，不能采用断开 PLC 的连接电缆等手段停止通讯。 KV-H20/H20S/H40S/H20G 单元的 JOG 继电器会一直保持 ON，机器继续运转，并可能导致事故发生。 3、执行监控或者写入参数（设定）时，不能断开和 PLC 的连接电缆。 否则会发生通讯错误，PC 可能会被重启。KV-H20/H20S/H40S/H20G 内的数据可 能会损坏。 4、在 RUN 过程中，KV-1000/700 进行 JOG 示教时，必须在 PROG 模式下实施。 如果扫描时间较长，则反映的时间变长，且可能发生无法预料的动作。 5、发送到 KV-1000/700 的单元设定信息必须与当前打开的梯形图程序的单元设定信 息一致。如果设定信息不同，则显示错误，且不运行。 6、错误操作或者静电等会引起数据变化或者去失，为了保护数据，请定期进行备份。 指示 关于数据的变化或者消失引起的损失，本公司不负任何责任，请谅解。 7、保存数据时，如果需要保留原来保存的数据，则选择“重命名保存”。 如果“覆盖保存”则会失去原来保存的数据。 运行环境及系统配置 运行 MOTION BUILDER Ver.2 ，必须具备如下环境。 请确认您使用的系统是否符合如下条件、是否备齐了必需的设备。 对应的 PC 机型 • IBM PC 以及 PC/AT 兼容机（DOS/V） 系统配置 • CPU Pentium 133 MHz 以上 支持 Windows 的打印 （推荐 Pentium 200 MHz 以上） • 内存容量扩展内存 64MB 以上 • 硬盘可用空间 20MB 以上 • CD-ROM 驱动器 • 接口 RS-232C 或者 USB
上传时间： 2013-10-08
上传用户：fujiura
ExpressPCB 是一款免费的PCB设计软件，简单实使。可以画双层板。 Our Free PCB software is a snap to learn and use. For the first time, designing circuit boards is simple for the beginner and efficient for the professional. Our board manufacturing service makes top quality two and four layer PCBs. Use our MiniBoard service and pay only $51 for three boards (plus $8 shipping).
标签： ExpressPCB PCB 设计软件
上传时间： 2013-11-15
上传用户：lchjng
ExpressPCB 是一款免费的PCB设计软件，简单实使。可以画双层板。 Our Free PCB software is a snap to learn and use. For the first time, designing circuit boards is simple for the beginner and efficient for the professional. Our board manufacturing service makes top quality two and four layer PCBs. Use our MiniBoard service and pay only $51 for three boards (plus $8 shipping).
标签： ExpressPCB PCB 设计软件
上传时间： 2013-10-09
上传用户：1047385479
AD10以上版本可能安装的问题没有这个PCB Logo Creator文件，无法加载LOGO，这个文件下载完放在AD安装目录下，然后打开软件目录DXP-Run ｓｃｒｉｐｔ然后加载里面的文件就OK了！
上传时间： 2013-10-20
上传用户：blacklee
This white paper discusses how market trends, the need for increased productivity, and new legislation have accelerated the use of safety systems in industrial machinery. This TÜV-qualified FPGA design methodology is changing the paradigms of safety designs and will greatly reduce development effort, system complexity, and time to market. This allows FPGA users to design their own customized safety controllers and provides a significant competitive advantage over traditional microcontroller or ASIC-based designs. Introduction The basic motivation of deploying functional safety systems is to ensure safe operation as well as safe behavior in cases of failure. Examples of functional safety systems include train brakes, proximity sensors for hazardous areas around machines such as fast-moving robots, and distributed control systems in process automation equipment such as those used in petrochemical plants. The International Electrotechnical Commission’s standard, IEC 61508: “Functional safety of electrical/electronic/programmable electronic safety-related systems,” is understood as the standard for designing safety systems for electrical, electronic, and programmable electronic (E/E/PE) equipment. This standard was developed in the mid-1980s and has been revised several times to cover the technical advances in various industries. In addition, derivative standards have been developed for specific markets and applications that prescribe the particular requirements on functional safety systems in these industry applications. Example applications include process automation (IEC 61511), machine automation (IEC 62061), transportation (railway EN 50128), medical (IEC 62304), automotive (ISO 26262), power generation, distribution, and transportation. 图Figure 1. Local Safety System
上传时间： 2013-11-14
上传用户：zoudejile
通过以太网远程配置Nios II 处理器 应用笔记 Firmware in embedded hardware systems is frequently updated over the Ethernet. For embedded systems that comprise a discrete microprocessor and the devices it controls, the firmware is the software image run by the microprocessor. When the embedded system includes an FPGA, firmware updates include updates of the hardware image on the FPGA. If the FPGA includes a Nios® II soft processor, you can upgrade both the Nios II processor—as part of the FPGA image—and the software that the Nios II processor runs, in a single remote configuration session.
上传时间： 2013-11-22
上传用户：chaisz
