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101.
本文系统地介绍了一种双波长光纤测温仪的原理、结构及特点,其突出优点有:采用双波长窄带比较技术和以微控制器,可编程外围芯片为核心,构成数字化、小型化光纤传感系统,抗干扰能力强,具有通信接口,可与过程控制网络连接,支持流行的现场总线协 相似文献
102.
In this paper, a modified broadband bow-tie antenna with low cross-polarization level and miniaturization is presented. The cross-polarization in both E- and H-planes are suppressed by defecting the antenna flares using rectangular slots. The proposed modified antenna demonstrated a cross-polarization improvement over around the boresight from 2 to 5 GHz. In addition, an overall 23.5% of miniaturization compared to conventional bow-tie antenna is achieved. A tapered feed transition between microstrip-to-parallel stripline is designed to match 50 ohm SMA connector to the antenna flares. A prototype of the modified antenna is fabricated on RO4003 substrate (r = 3.38, tan = 0.0027, h = 0.813 mm), and its performance is experimentally studied. The antenna’s characteristics including return loss, gain and radiation pattern are measured, along with the time domain characteristics, and showed reasonable agreement with the simulated results. 相似文献
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Nagendra Bhargava Bharatula Paul Lukowicz Gerhard Tröster 《Personal and Ubiquitous Computing》2008,12(2):123-141
Wearable computing places tighter constraints on architecture design than traditional mobile computing. The architecture is
described in terms of miniaturization, power-awareness, global low-power design and suitability for an application. In this
article we present a new methodology based on three different system properties. Functionality, power and electronic Packaging
metrics are proposed and evaluated to study different trade offs. We analyze the trade offs in different context recognition
scenarios. The proof of concept case study is analyzed by studying (a) interaction with household appliances by a wrist worn
device (acceleration, light sensors) (b) studying walking behavior with acceleration sensors, (c) computational task and (d)
gesture recognition in a wood-workshop using the combination of accelerometer and microphone sensors. After analyzing the
case study, we highlight the size aspect by electronic packaging for a given functionality and present the miniaturization
trends for ‘autonomous sensor button’. 相似文献
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针对贫点阵探测器,设计了一套多处理器信息获取系统.介绍了系统的总体架构,着重讨论了多处理器模块功能实现方法和小型化设计方案.采用分时复用技术进行多通道信号采集,采用SMBus总线进行数据传输,采用三单片机协同工作方式提高系统速度,采用双频工作模式降低系统功耗,采用堆叠式组装技术减小系统体积.该系统探测帧率大于1 kHz,峰值工作电流小于30 mA,最大功耗小于100 mW,体积控制在西10 mm×12 mm的空间内,适用于微小型光电目标探测领域. 相似文献
107.
G. Hirt 《CIRP Annals》2008,57(1):317-320
Due to functional enhancement and beneficial product properties, surface structuring of large semi-finished products and part components becomes more important. Rolling of so-called riblet structures for drag reduction on surfaces in fluid-dynamics is presented within this contribution. The examination of a novel roll structuring process via defined steel wire winding is the primary topic. Both practical experiments and numerical simulations of the riblet rolling process point out potentials and limitations of the new structuring approach. Rolling of uniformly shaped riblets with a lateral distance of less than 100 μm is assumed to be possible on large sheets in future. 相似文献
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秦舒 《电子工业专用设备》2013,(10):39-42
在对巴伦的基本原理和耦合传输线奇偶模阻抗特性研究的基础上,基于LTCC技术设计了中心频率为1.35GHz的小型化MarchandBalun。设计中使用宽边耦合带状线来实现MarchandBalun内部的耦合区段。仿真结果表明,MarchandBalun的中心频率为1.35GHz,S11为.31.39dB;带内插入损耗在-0.55~1.12dB之间,满足设计指标的要求。 相似文献