共查询到20条相似文献,搜索用时 125 毫秒
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参量换能器收发电路设计 总被引:1,自引:1,他引:1
介绍了超声波参量换能器的工作原理,设计了一种声学参量换能器结构、超声波发射电路和声波接收电路。发射电路由正弦信号产生电路、功率放大电路和补偿电路等组成,声波接收电路由前置放大电路和带通滤波电路组成,并利用NI公司的6024E数据采集卡进行数据采集。理论分析表明,当原波信号为87 kHz时,利用该收发电路可以较好地实现参量阵差频信号的发射与接收。 相似文献
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针对超宽带通信的应用特点,设计了一个IR-UWB通信实验系统,在发射端采用雪崩三极管产生超宽带窄脉冲,在接收端利用高速比较器实现超宽带窄脉冲的检测接收,并应用Multisim 11.0对两部分进行仿真,且通过制作实物电路进行性能测试和验证.测试结果表明,发射端产生的脉冲信号波形良好,基本形状符合超宽带要求;接收端电路也能取得较好的超宽带脉冲检测效果. 相似文献
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改进型相位式激光测距电路的设计 总被引:1,自引:0,他引:1
为了提高无合作目标的相位式激光测距系统的稳定性和精度,并简化测距系统,设计了一种相位式激光测距系统的发射和接收电路.采用了双频调制、直接数字频率合成器(DDS)、差频测相技术等原理.进行了理论的研究、分析和实际的电路实验.利用DDS产生的正弦波信号进行调制发射,并且对非合作目标反射回来的激光信号进行接收、调理,并进行数据处理.在设计中,优化了系统的调制发射电路,采用新的光电探测器和高压偏置电路,增加简单实用的自动增益控制(AGC)模块等.实验结果表明,该测距系统简单有效,具有较高的测量精度和稳定性. 相似文献
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基于单片机的倒车防撞预警系统设计和实现 总被引:1,自引:1,他引:0
汽车倒车防撞预警系统是汽车泊车辅助装置。系统由超声波发射与回波接收电路、超声波电信号放大电路、单片机控制电路、显示电路和声音报警电路组成,根据超声波测距原理,实现倒车防撞预警。给出了硬件各单元电路图,软件主要模块的流程图,说明设计过程和工作原理。采用通用型单片机作为控制电路,方便功能扩展,充分利用单片机的内部资源,外围元件少、电路简洁、成本低、实用性强。 相似文献
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A novel efficient circuit for Ultra-WideBand (UWB) balanced sub-nanosecond monocycle pulse generation is presented. The pulse generator employs wideband bipolar transistor, step recovery diodes, Schottky diodes, and simple charging and discharging circuitry. Simple transient analysis and design of the circuit are presented along with their operating principle. The pulse generator produces truly balanced monocycle pulse with 500 ps pulse-width and 800 mV peak voltage. The generated monocycle pulse also has very symmetrical positive and negative portions and low ringing level. The presented pulse generator can be used as both a transmitter feeding UWB balanced antennas without broadband baluns and a balanced switching pulse generator that used in UWB receiver. 相似文献
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Terada T. Yoshizumi S. Muqsith M. Sanada Y. Kuroda T. 《Solid-State Circuits, IEEE Journal of》2006,41(4):891-898
A CMOS ultra-wideband impulse radio (UWB-IR) transceiver was developed in 0.18-/spl mu/m CMOS technology. It can be used for 1-Mb/s data communications as well as for precise range finding within an error of /spl plusmn/2.5 cm. The power consumptions of the transmitter and receiver for data communication are 0.7 and 4.0 mW, respectively. When an LNA operates intermittently through bias switching, the power consumption of the transceiver is only 1 mW. The range for data communication is 1 m with BER of 10/sup -3/. For ranging applications, the transmitter can reduce the power to 0.7 /spl mu/W for 1k pulses per second, and the receiver consumes little power. The transceiver design, all-digital transmitter, and intermittent circuit operation at the receiver reduce the power consumption dramatically, which makes the transceiver well suited for applications like sensor networks. The electronic field intensity is lower than 35 /spl mu/V/m, and thus the UWB system can be operated even under the current Japan radio regulations. 相似文献
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Receiver Power Allocation and Transmitter Power Control Analysis for Multiple-Receiver Wireless Power Transfer Systems
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As different power has its own receivers, this paper analyzes and designs a multiple-receiver wireless power transfer (WPT) system systematically. The equivalent circuit model of the system is established to analyze the key parameters including transmitter power, receiver power, transmission efficiency, and each receiver power allocation. A control circuit is proposed to achieve the maximum transmission efficiency and transmitter power control and arbitrary receiver power allocation ratios for different receivers. Through the proposed control circuit, receivers with different loads can allocate appropriate power according to its power demand, the transmitter power and system efficiency do not vary with the change of the number of receivers. Finally, this control circuit is validated using a 130-kHz WPT system with three receivers whose power received is 3:10:12, and the overall system efficiency can reach as high as 55.5%. 相似文献
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Wong Tat Tung Jiangzhou Wang 《Vehicular Technology, IEEE Transactions on》2005,54(2):603-614
Multicarrier direct-sequence code-division multiple-access (MC-CDMA) overlay has been proposed to be used for ultra-wide-band (UWB) communications. Interference reduction and interference suppression are the key issues for sharing the spectrum in harmony between the established narrow-band systems and the overlaid UWB system. In this paper, investigation is carried out on the use of compromising measures incorporated to the MC-CDMA overlay to meet these goals, as well as on their impacts to the involving parties. At the transmitter, interference reduction to the established narrow-band systems is done by using notch filters. A multipath Nakagami fading channel is assumed. At the receiver, the interference suppression from those narrow-band systems is fulfilled by minimum mean square error (MMSE) detection technique. Numerical results show that precombining MMSE with selective-maximal combining provides the UWB system with much better performance than the receiver made up of notch filter in cascade with code correlator. 相似文献
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For an indoor ultra-wideband (UWB) communication system, the line-of-sight (LOS) between the transmitter and receiver may be frequently blocked by moving people. Blocking of LOS may significantly affect the quality of service of on-going UWB communications. Based on the Angular Power Spectrum Density and the human blocking models, we build a packet-level UWB channel model considering the shadowing processes based on a Finite-state Markov Chain. The model is simple enough to be incorporated into existing network simulators like NS-2 and it can be used to facilitate protocol design and quality of service analysis for UWB based wireless personal area networks. 相似文献
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由于高传输速率及多径效应的影响,在窄脉冲超宽带(IR-UWB)通信系统中,基于传统横向滤波器的时域均衡技术已无法对抗严重的码间干扰。通过收发两端联合设计,提出了一种以数据块为基础的基于码元的频域均衡技术,同时介绍了其应用前提和算法实现。仿真结果表明,所提方法能有效对抗超宽带通信系统中存在的码间干扰,是窄脉冲超宽带通信系统中更为现实的技术选择。 相似文献
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《Lightwave Technology, Journal of》2009,27(18):4112-4123