共查询到19条相似文献,搜索用时 109 毫秒
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高速PCB的设计中,数模混合电路的PCB设计中的干扰问题一直是一个难题。尤其模拟电路一般是信号的源头,能否正确接收和转换信号是PCB设计要考虑的重要因素。文章通过分析混合电路干扰产生的机理,结合设计实践,探讨了混合电路一般处理方法,并通过设计实例得到验证。 相似文献
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提高电磁兼容性的混合信号PCB的分区设计 总被引:1,自引:0,他引:1
电子电路和系统的电磁兼容性近年来越来越受到重视,这导致对设备电磁特性的要求越来越严格。提高电子电路和系统的电磁兼容性需要考虑两个方面的特性:电路产生尽量少或者不产生干扰以及电路对遭遇到的电磁能量的影响的抵制力。本文主要从印刷电路板的混合信号布局的角度来阐述提高电子产品电磁兼容性的混合信号PCB的分区设计。 相似文献
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基于ATM网络的数据采集接入电路设计与实现 总被引:2,自引:1,他引:1
阐述基于ATM(异步传输模式)网络的数据采集接入电路的设计方法,介绍了系统接入电路中的核心电路,即差分混合接入电路,证明了实现发送与接收之间的最小干扰关系,并根据线路要求采用了ADSL网络专用的AD8016作为放大器,最后给出了实际应用电路。 相似文献
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为解决电容积分式电流检测法不能满足FAIMS快速测量要求的问题,设计了一种用于FAIMS系统的微电流检测电路。采用合理的元器件和电路设计,运用两级放大将FAIMs系统中的pA级电流放大并转换到ITIV量级。为了消除FAIMS系统中高频噪声的干扰,对电路进行屏蔽设计,从而有效滤除了系统的干扰噪声,放大后的信号通过NI采集卡,并利用LabVIEw对测得的电流信号进行采集和数据处理。实验结果表明,该电路的测量精度优于0.1pA,采样频率高于15HZ。进行了FA1MS系统实验,测得系统输出的背景噪声为0.2pA。以乙醇为实验样品,在载气(N。)流量为0.8L/min的情况下,得到了乙醇的FAIMs谱图,证明了该微电流检测电路屏蔽能有效滤除FAIMS系统的噪声干扰。 相似文献
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利用数字储频技术对综合脉压雷达实施干扰的研究及应用 总被引:2,自引:2,他引:0
提出了应用数字储频技术对综合脉冲压缩雷达进行干扰的理论,并设计了一种3bit相位量化DRFM系统。该系统通过采用正交双通道零中频处理量化相位,处理效果较佳。它包含了相位量化器、数据存储和加权相加三部分电路。 相似文献
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提出基于ADSP-TS101的信号处理系统,引入信号完整性分析,通过对数模混合部分,高密度(HD)电路及系统时钟的设计,从布局、布线等方面研究了高速数字电路硬件设计的几个关键技术,较好地解决了系统中主处理器在较高工作频率下稳定工作的问题,提高了系统性能.通过仿真结果基本达到设计要求. 相似文献
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在电子线路版图设计中,通常采用印刷线路板技术。如果结合厚膜工艺技术,可以实现元器件数目繁多,电路连接复杂,且安装空间狭小的电路版图设计。通过对3种不同电路版图设计方案的理论分析,确定了惟一能满足要求的设计方案。基于外形尺寸的要求,综合考虑电路的性能和元件的封装形式,通过合理的电路分割和布局设计,验证了设计方案的合理性和可实现性。体现了厚膜工艺技术在电路版图设计中强大的优越性,使一个按常规的方法无法实现的电路版图设计问题迎刃而解。 相似文献
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分析了混合集成DC/DC变换器的电路和工艺特点,结合高可靠混合集成DC/DC变换器的设计应用要求,提出了一种适用于高可靠混合集成DC/DC变换器的限流和短路保护电路。从原理上阐述了限流和短路保护的设计方法,给出了具体电路和仿真数据。结合实际电路测试数据,提出了类似电路设计中的改进措施。 相似文献
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《Microwave Theory and Techniques》1981,29(3):194-202
A fully computer-oriented synthesis of the optimum circuit pattern of a 3-dB hybrid ring based upon the planar circuit concept is described. In the synthesis process, the contour-integral method, and Powell's method are used for the circuit analysis, the optimization, respectively. The synthesized optimum patterns are given in normalized curves, parameters which can directly be used in practical circuit design. The validity of the theory is confirmed by experiment. It is shown both theoretically, experimentally that the planar circuit approach can, not only prevent the deterioration of the hybrid characteristics due to the widening of the circuit, but bring forth hybrid characteristics somewhat better than the distributed constant model. It is also shown that the obtained optimized characteristics can further be improved by addition of simple external circuits. 相似文献
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文章设计并实现了C L波段4泵浦光纤拉曼放大器(FRA),讨论了泵浦驱动电路的设计及掺铒光纤放大器(EDFA)与FRA 150 km混合传输的传输性能.实验结果表明,驱动电路可以稳定可靠地工作,当拉曼放大器的增益<5 dB时,信号的误码性能不会得到显著提高.实验结果可为EDFA与FRA混合传输系统中增益的配置提供参考. 相似文献
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Ohmine H. Sunahara Y. Matsunaga M. 《Antennas and Propagation, IEEE Transactions on》1997,45(6):1001-1008
A new configuration of circularly polarized annular-ring microstrip antenna (ARMSA) fed by a branch-line hybrid coupler placed at the inner part of the ARMSA and its design method using an equivalent circuit are presented. Since the ARMSA has a narrow bandwidth and high-input impedance, a parasitic element placed above the ARMSA is employed for not only obtaining a broadband characteristic, but decreasing the input impedance down to 50 Ω. A hybrid coupler to generate circular polarization, therefore, can be connected to the co-planar space of the ARMSA directly without a large-size matching circuit and a very low profile and simple structure can be achieved. The ARMSA is excited at the TM21 mode to produce a conical pattern, which has a high gain in a low-elevation angle for mobile satellite communications. An effective design method using the equivalent circuit is indicated and, as a result, it is obvious that a broadband characteristic is obtained when each resonant frequency of the ARMSA and parasitic element is identical. Experimental results in the L-band showed satisfactory characteristics for vehicle antennas 相似文献
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A new hybrid ring coupler design is devised for circuit miniaturization based on the periodic stepped-impedance ring resonator structure. The circuit has an area of 21.5% of a conventional rat race coupler and no passband up to the sixth harmonic of the design frequency. The designs are validated by comparing measured four-port parameters with the simulated results 相似文献
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Yun-Nan Chang 《The Journal of VLSI Signal Processing》2003,33(3):317-324
This paper presents a novel design of Viterbi decoder based on in-place state metric update and hybrid survivor path management. By exploiting the in-place computation feature of the Viterbi algorithm, the proposed design methodology can result in high-speed and modular architectures suitable for those Viterbi applications with large constraint length. This feature is not only applied to the design of highly regular ACS units, but also exploited in the design of trace-back units for the first time. The proposed hybrid survivor path management based on the combination of register-exchange and trace-back schemes cannot only reduce the number of memory operations, but also the size of memory required. Compared with the general hybrid trace-back structure, the overhead of register-exchange circuit in our architecture is significantly less. Therefore, the proposed architecture can find promising applications in digital communication systems where high-speed large state Viterbi decoders are desirable. 相似文献