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  • 无线电设计入门资料

    Abstract: The process of designing a radio system can be complex and often involves many project tradeoffs. Witha little insight, balancing these various characteristics can make the job of designing a radio system easier. Thistutorial explores these tradeoffs and provides details to consider for various radio applications. With a focus on theindustrial, scientific, medical (ISM) bands, the subjects of frequency selection, one-way versus two-way systems,modulation techniques, cost, antenna options, power-supply influences, effects on range, and protocol selectionare explored.

    标签: 无线

    上传时间: 2013-12-12

    上传用户:eastgan

  • 如何优化ISM无线电频率(RF)系统

    Abstract: With industrial/scientific/medical (ISM) band radio frequency (RF) products, often times users are new to the structure of Maxim's low pin-count transmitters andfully integrated superheterodyne receivers. This tutorial provides simple steps that can be taken to get the best performance out of these transmitters and receivers whileproviding techniques to measure the overall capability of the design.

    标签: ISM RF 无线电频率

    上传时间: 2013-11-02

    上传用户:yph853211

  • 无线电干扰 Radio Susceptibility

      Abstract: Engineers often wish that radio susceptibility (RS) or radio immunity could be cured with an antibiotic, a vaccine, or someform of cure-all. Unfortunately, solving the RS problem is not that easy. Indeed, the laws of physics apply. In this article we discusssources of RS. We also offer tips and hints to protect systems, power supplies, printed circuit boards (PCBs), and electroniccomponents from radio frequency interference.

    标签: Susceptibility Radio 无线电干扰

    上传时间: 2014-12-30

    上传用户:旗鱼旗鱼

  • wp379 AXI4即插即用IP

    In the past decade, the size and complexity of manyFPGA designs exceeds the time and resourcesavailable to most design teams, making the use andreuse of Intellectual Property (IP) imperative.However, integrating numerous IP blocks acquiredfrom both internal and external sources can be adaunting challenge that often extends, rather thanshortens, design time. As today's designs integrateincreasing amounts of functionality, it is vital thatdesigners have access to proven, up-to-date IP fromreliable sources.

    标签: AXI4 379 wp 即插即用

    上传时间: 2013-11-11

    上传用户:csgcd001

  • 高精度温度测量铂电阻温度探测器(PRTDs)和​​ADC

    Abstract: Many modern industrial, medical, and commercial applications require temperature measurements in the extended temperature rangewith accuracies of ±0.3°C or better, performed with reasonable cost and often with low power consumption. This article explains how platinumresistance temperature detectors (PRTDs) can perform measurements over wide temperature ranges of -200°C to +850°C, with absolute accuracyand repeatability better than ±0.3°C, when used with modern processors capable of resolving nonlinear mathematical equation quickly and costeffectively. This article is the second installment of a series on PRTDs. For the first installment, please read application note 4875, "High-Accuracy Temperature Measurements Call for Platinum Resistance Temperature Detectors (PRTDs) and Precision Delta-Sigma ADCs."

    标签: PRTDs ADC 高精度 温度测量

    上传时间: 2013-11-06

    上传用户:WMC_geophy

  • 能量收集系统的设计挑战

    Modern electronic systems solve so many difficult problems that they often seem like magic. Nonetheless, these systems all have thesame basic limitation: they need a source of electrical power! Most of the time this is a straightforward challenge for the electronicdesigner, because there are many power-delivery solutions. Yet sometimes a device has no direct power source, and running wiresor replacing batteries is impractical. Even when long-life batteries are usable, they eventually need to be replaced, which requires aservice call.

    标签: 能量收集

    上传时间: 2015-01-02

    上传用户:zukfu

  • 低噪声电压基准的噪声测量

      Frequently, voltage reference stability and noise defi nemeasurement limits in instrumentation systems. In particular,reference noise often sets stable resolution limits.Reference voltages have decreased with the continuingdrop in system power supply voltages, making referencenoise increasingly important. The compressed signalprocessing range mandates a commensurate reductionin reference noise to maintain resolution. Noise ultimatelytranslates into quantization uncertainty in A to D converters,introducing jitter in applications such as scales, inertialnavigation systems, infrared thermography, DVMs andmedical imaging apparatus. A new low voltage reference,the LTC6655, has only 0.3ppm (775nV) noise at 2.5VOUT.Figure 1 lists salient specifi cations in tabular form. Accuracyand temperature coeffi cient are characteristic ofhigh grade, low voltage references. 0.1Hz to 10Hz noise,particularly noteworthy, is unequalled by any low voltageelectronic reference.

    标签: 低噪声 电压基准 噪声测量

    上传时间: 2013-10-30

    上传用户:wxhwjf

  • This Unix C code monitors a web server every few minutes by trying to retrieve its home page. It sen

    This Unix C code monitors a web server every few minutes by trying to retrieve its home page. It sends you email when it can t connect, and every so often while the server is still down. It sends a final message when it comes back up. If you have email paging, just direct the email to your pager address.

    标签: monitors retrieve minutes server

    上传时间: 2015-01-11

    上传用户:pompey

  • 自制51编程器 I have build my own programmer. This device can program the AT89C51 and works with it. So i

    自制51编程器 I have build my own programmer. This device can program the AT89C51 and works with it. So it can easily be adapted to programming other devices by itself. The Atmel Flash devices are ideal for developing, since they can be reprogrammed easy, often and fast. You need only 1 or 2 devices in low cost plastic case for developing. In contrast you need 10 or more high cost windowed devices if you must develop with EPROM devices (e.g. Phillips 87C751).

    标签: programmer program device build

    上传时间: 2015-05-11

    上传用户:sdq_123

  • Decoding most of the infrared signals can be easily handled by PIC16C5X microcontrollers. This appl

    Decoding most of the infrared signals can be easily handled by PIC16C5X microcontrollers. This application note describes how this decoding may be done. The only mandatory hardware for decoding IR signals is an infrared receiver. The use of two types is described here. Both are modular types used often by the consumer electronics industry. The first type responds to infrared signals modulated at about 40 kHz. The second responds to non-modulated infrared pulses and has a restricted range. The hardware costs of each approach will be less than two dollars.

    标签: microcontrollers Decoding infrared handled

    上传时间: 2015-05-24

    上传用户:ruan2570406