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王铁红 《光电对抗与无源干扰》2002,(2):46-50
本文研究了系统总体设计的框架,系统总体设计的方法和步骤,阐述了工程系统软硬件系统和对上,对下接口关系的综合设计,讨论了系统总体设计的综合平衡,介绍了在工程实践中的两个评审的重要性。 相似文献
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阐述了3G室内覆盖系统建设的必要性,提出室内覆盖系统的建设原则,对室内覆盖系统的建设模式进行了分析,详细介绍了室内分布系统的组成、应用场所,对共用室内分布系统进行了探讨,最后提出了3G室内覆盖系统建设的一些建议。 相似文献
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随着数字化技术的日臻成熟,对数字系统的理论研究也越来越深入,数字系统的失真作为一种数字系统的一项重要指标,本文通过对PCM原理,数字音频系统构成部件及工作流程的分析,对数字音频系统的失真进行了总结和归纳,对其如何产生,对音质有何影响,进行了深入的研究和思考。 相似文献
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本文介绍一种与IBMPC机配合使用的数据采集系统的设计方法。该系统是对现有数据采集系统作了适当改进,输入通道增加了可调增益前置放大,输出通道配置了低通滤波,使系统输入信号范围大大扩大,系统的适应性和抗干扰性得到增强;另外对控制电路也作了部分简化,使改进后的数据采集系统更加经济实用。实验证明,该系统工作正常,各项性能指标稳定可靠,具有推广应用价值。 相似文献
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ML-300型助焊剂喷涂系统 总被引:2,自引:0,他引:2
介绍了一种新型助焊剂喷涂系统,利用该系统可对旧的发泡系统进行改造,列出了该系统的技术特征以及技术参数,并对改造后的PCB焊接效果进行了讨论。 相似文献
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ATR毫米波雷达目标特征信号自动测量系统 总被引:1,自引:0,他引:1
介绍了ATR毫米波雷达目标特征信号自动测量系统,该系统为宽带高分辨全极化雷达系统,提供了三种测量方式和两种正交极化对。介绍了测量系统的管理和控制软件,并对测量系统的性能作了评估,还给出了部分测量结果。 相似文献
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对当前无线通信中的热点问题,如无线拉入系统,第三代移动通信系统,双向寻呼移动通信系统,数字集群通信系统以及蓝牙技术等,就它们对频率使用的有关问题进行了综述。 相似文献
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Richard Mudhar 《International Journal of Communication Systems》1992,5(2):77-83
Passive optical networks (PONs) are attractive for the provision of telephony via optical fibre in the local loop, and have generally tended to concentrate on the use of time-division multiple access for transmission. This paper describes a hybrid transmission method using sub-carrier multiplexing (SCM) and time division multiplexing (TDM) which seeks to reduce the overall complexity of the system, thereby lowering costs. 相似文献
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本文首先回顾了北京地区PDH光纤传输网的情况,然后结合信息高速公路的发展,介绍了北京地区光纤数字同步网的建设和目前的设备配置。 相似文献
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We propose a 10-Gb/s WavelengthDivision-Multiplexed Passive Optical Network(WDM-PON) scheme with upstream transmission employing Reflective Semiconductor Optical Amplifier(RSOA) and Fibre Bragg Grating(FBG) optical equaliser.Transmissions of10-Gb/s non return-to-zero signals using a 1.2-GHz RSOA and FBG optical equaliser with different setups are demonstrated.Significant performance improvement and 40-km standard single mode fibre transmission are achieved using FBG optical equaliser and Remotely Pumped Erbium-Doped Fibre Amplifier(RP-EDFA),where they are used to equalise the output of the band-limited RSOA and amplify the seed light and upstream signal,respectively. 相似文献
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Masayoshi Kamiya Hiroaki Ikeda Shigenobu Shinohara 《International Journal of Communication Systems》2001,14(5):477-485
This paper describes a low‐cost version of a full‐duplex optical fibre analogue/digital data transmission link whose practical implementation is simplified by using a pair of laser diodes, each having a built‐in photodiode for monitoring the laser output power, and its application to vibration test data transmission. The transmission link sends digital data of up to 9600 bps in one direction, and analogue data of DC to 100 kHz and image data specified by an NTSC colour video signal in the opposite direction, all at the same time through one GI optical fibre. Being simple in configuration and stable against noise, this type of link has a variety of applications within factory, home and offices. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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Takahide Nishio Nabil Abd Rabou Hiroaki Ikeda Hirofumi Yoshida Yoshiro Sugimoto Tsutomu Satoh 《International Journal of Communication Systems》1999,12(1):1-10
This paper describes a single‐mode(SM) optical fibre SSB data communication system for use in place of power‐line data transmission. In the optical transmitter, SSB data is fed through the squarewave frequency (SWFM) modulator to the edge‐emitting LED (ELED) module. The light beam of the ELED module is fed to the SM optical fibre having a length of 12km. In the optical receiver, the light beam received through the SM optical fibre is detected by the PIN photodiode module, and fed to the SWFM detector to obtain the double‐pulse frequency modulation (DPFM) signal voltage. The DPFM signal voltage at the output of the SWFM detector is fed to the low‐pass filter (LPF) to obtain analogue SSB data. When the transmission was experimentally carried out, the spurious component was as low as −50–−70 dB and the SNR of SSB data as high as more than 65–70 dB. The optical transmitter and receiver were attached to the conventional analogue SSB data communication system to constitute a new optical fibre analogue SSB data communication system. During the field test utilizing the new system, the crosstalk and SNR were 60–70 dB and 60–70 dB on each channel, respectively. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
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本文介绍聚合物光纤领域中梯度折射率聚合物光纤的带宽、谱损、稳定性和高速传输实验,以及氟化聚合物光纤、聚合物光纤连接器和放大器方面研究的最新进展. 相似文献