一种超宽带脉冲信号发生器的设计

介绍一种利用并联阶跃恢复二极管(SRD)产生超宽带窄脉冲信号的微带结构电路,该电路可产生宽度为1ns、重复周期为100MHz的窄脉冲信号,其峰值电压达10.44V。文章分析讨论了电路原理与设计方法,并重点研究了偏置电路与匹配电路的设计问题。测量结果显示该电路所产生的脉冲信号具有良好的波形,并且脉冲拖尾的振荡起伏很小,是一种适合于超宽带通信系统的窄脉冲信号形成电路。     

超宽带脉冲产生电路的研究与设计

在UWB脉冲信号发生器的研制中,通过分析UWB脉冲波形的特征,以一阶高斯脉冲为设计目标,提出了一种以振荡源、储能元件和高速开关为主体的UWB脉冲产生电路系统模型,并且在实际电路中设计了不同的实现方式。利用复杂可编程器件(CPLD)为UWB脉冲发生模块设计了脉冲时序触发电路。针对脉冲的产生方案,设计了一种利用雪崩晶体管产生UWB脉冲的电路,实际测试得到了1 ns以内的窄脉冲;与此同时设计了一种基于阶跃恢复二极管的UWB脉冲发生电路,在PSpice中仿真得到了宽度约400 ps的UWB脉冲信号。仿真结果表明,PSpice建立的SRD模型符合理论分析,设计的UWB脉冲信号发生电路也完全满足在超宽带引信上使用的需求。     

超宽带Scholtz’s单周期脉冲的产生电路设计

以并联阶跃恢复二极管（SRD）窄脉冲发生器为基础,结合简单的RLC电路,设计一种直接产生Scholtz’s单周期脉冲的电路结构。这种脉冲近似二次微分高斯脉冲,是超宽带系统中使用较多的一种波形。文章主要讨论了电路原理与设计方法,并进行了仿真验证。仿真结果显示该电路所产生的脉冲信号具有良好的波形,是一种适合于超宽带通信系统的窄脉冲信号产生电路。     

用于激光脉冲整形的电脉冲产生技术

介绍了一种用于激光脉冲整形的超宽带脉冲产生方法.电路中利用阶跃恢复二极管(SRD)载流子可控、截止速度快的特点,采用对阶跃恢复二极管进行串并联相结合的方法设计了超宽带脉冲产生电路.给出了实际电路的测试结果,并且对实验结果在物理层面上进行了理论分析,实验结果与理论分析结果吻合.此脉冲产生电路可输出幅度约10V,脉冲宽度约...     

双非门结构皮秒级窄脉冲设计

窄脉冲的产生是超宽带通信系统中的一项关键技术,不同的应用对脉冲的产生方法有不同的要求。文中分析了超宽带室内定位系统中几种常规的超宽带窄脉冲产生方法,比较了它们的优缺点,对存在的问题进行了研究。在此基础上首先设计了一种基于数字方法的脉冲发生器,通过对该脉冲发生器的仿真分析提出了一种基于双非门结构的超宽带窄脉冲的产生方法,仿真结果表明,利用该方法得到的脉冲重复频率为10 MHz,宽度为150 ps。实验电路测试结果与理论分析和仿真结果基本一致。相电路比常规的数字电路窄脉冲产生方法,该设计方法不仅电路简单,对器件的要求不高,成本低,而且脉冲宽度变窄了十几倍,定位精度更高。     

一种简易的超宽带纳秒级脉冲发生器设计

为了得到超宽带纳秒级窄脉冲信号,在对UWB脉冲产生方法分析总结的基础上,提出了一种基于数字逻辑器件的简单脉冲产生电路。对实际制做的电路进行了测试,能够得到重复频率为10 MHz,脉冲宽度约为4ns,幅度约为500mV的窄脉冲。该电路成本低,结构简单,易于制作,工程实用性较强。     

一种用于UWB-TWSR的窄脉冲产生电路的设计

实现TWSR(穿墙探测雷达)技术的关键之一是如何设计并产生可以控制的UWB窄脉冲.为此,文中介绍了TWSR的基本概念及工作原理,讨论了几种UWB中常用的窄脉冲产生方法和特点;给出了一种基于RF-BJT雪崩特性的UWB窄脉冲产生电路,同时进行了仿真调试.通过该电路可获得峰值电压为-10.1 V、宽度为654.8 ps的单极性UWB窄脉冲.     

一种UWB脉冲发生器的设计与实现

本文重点讨论了如何利用阶跃恢复二极管(SRD)来实现极窄脉冲的产生,对这种脉冲发生器的原理和电路调试作了具体的分析。通过电路的变化最终得到两种不同的脉冲。     

电爆丝断路开关输出性能分析

电爆丝断路开关是电感储能系统中广泛应用的技术。文中首先分析了电爆丝断路开关(EEOS)在电感储能系统中工作的基本原理,在理论上分析了影响电爆丝断路开关输出性能的因素。接着设计了一组试验来验证理论分析。首先在同一电路中,相同起爆时刻,比较了铜丝和银丝输出的电压脉冲。从理论上分析了银丝比铜丝输出电压幅值更高,脉冲宽度更窄的原因。接着采用相同根数的铜丝,在电流大小不同电路中进行试验,结果发现电流大的回路产生的电压幅值更高,脉宽更窄。最后采用1根银丝和4根银丝进行实验。实验结果是1根银丝产生的脉冲宽度小,幅值大;4根银丝产生的脉冲宽度大,电压幅值小。然后得出结论金属丝状态变化过程中流过金属丝的电流密度影响产生电压脉冲的宽度。     

利用频率叠加的方法实现高重频高压窄脉冲源

利用传统方法实现高重频高压窄脉冲源受制于的器件性能,因而提出了频率叠加的新思路.基于超快电子学和频率叠加理论,利用MARX电路产生多路高压窄脉冲,通过同步系统控制多路触发信号延时,使多路脉冲耦合成一路输出,实现高重频高压窄脉冲输出.实验中两个单路高压窄脉冲的幅度为2.56 kV,宽度为7.13 ns,重复频率为32 k...     

Multilayer Heterostructures with Asymmetric Barriers as New Components for Nonlinear Transmission Lines to Generate High-Frequency Oscillations in the 100-300 GHz Range

A new method of generation of RF radiation in the range 100-300 GHz due to direct conversion of a video pulse into a radio pulse in nonlinear transmission line (NLTL) based on multilayer heterostructure (MLHS) with asymmetric barrier is suggested. Calculations of the capacitance-voltage characteristics and high-frequency loss in MLHS, and also of the MLHS-based NLTL dimensions are carried out with an analytical study and computer modeling of the shock wave propagation in NLTL. Some advantages of the considered method of generation in comparision with such solid state sources as Gunn devices, IMPATT diodes or different types of frequency multipliers are discussed.     

Characterization of Nonlinear Transmission Lines for Short Pulse Amplification

Pulse propagation on nonlinear transmission lines (NLTLs), which are transmission lines with regularly spaced Schottky varactors, is investigated for the amplification of short pulses. We recently found that the soliton developed in an NLTL experiences an exponential amplitude growth, when it couples with an existing voltage edge. This paper clarifies how the pulse gain depends on the device parameters, including the line inductance, capacitance, and gradient of voltage edge, and describes the design criteria of an NLTL as a pulse amplifier, together with several results of calculations that examine the potential of the NLTL.     

Nonlinear transmission lines for pulse shaping in silicon

Nonlinear transmission lines (NLTL) are used for pulse shaping. We developed the theory of pulse propagation through the NLTL. The problem of a wide pulse degenerating into multiple pulses rather than a single pulse is solved by using a gradually scaled NLTL. We exploit certain favorable properties of accumulation-mode MOS varactors to design an NLTL that can simultaneously sharpen both rising and falling edges. There is a good agreement among the theory, simulations, and measurements.     

Pulsed wave interconnect

Pulsed wave interconnect is proposed for global interconnect applications. Signals are represented by localized wave-packets that propagate along the interconnect lines at the local speed of light to trigger the receivers. Energy consumption is reduced through charging up only part of the interconnect lines and using the voltage doubling property of the receiver gate capacitances. In a 0.18-/spl mu/m CMOS technology case study, SPICE simulations show that pulsed wave interconnect can save up to 50% of energy and /spl sim/30% of chip area in comparison with the repeater insertion method. A proposed signal splitting structure provides reasonable isolations between different receivers. Measured S-parameters of 3.8-mm interconnect lines fabricated through CMOS foundry showed that the distortion and attenuation of a pico second signal are much less serious than the theoretical predictions. Pulsed wave interconnect also enables time division application of a single line to boost its bit rate capacity. The use of nonlinear transmission lines (NLTL) is also proposed to overcome pulse broadening and attenuation caused by dispersion and frequency-dependent losses. Pulsed waves on an NLTL may be generated, transmitted, split and detected with components realizable in bulk and SOI CMOS technologies. Tapered NLTL can be used for pulse compression. NLTL edge sharpening abilities may be applicable for signal rise time control.     

GaAs nonlinear transmission lines for picosecond pulse generation and millimeter-wave sampling

The GaAs nonlinear transmission line (NLTL) is a monolithic millimeter-wave integrated circuit consisting of a high-impedance transmission line loaded by reverse-biased Schottky contacts. The engineering of functional monolithic NLTLs is considered. Through generation of shock waves on the NLTL, the authors have generated electrical step functions with approximately 5 V magnitude and less than 1.4 ps fall time. Diode sampling bridges strobed by NLTL shock-wave generators have attained bandwidths approaching 300 GHz and have applications in instruments for millimeter-wave waveform and network measurements. The authors discuss the circuit design and diode design requirements for picosecond NLTL shock-wave generators and NLTL-driven sampling circuits.<>     

3kV皮秒冲击波的产生

用非线性传输线（ＮＬＴＬ）压缩纳秒光电导开关输出电压脉冲的上升时间，获得３ｋＶ，小于４００ｐｓ上升沿的高压冲击波脉冲。简述了ＮＬＴＬ冲击波理论，介绍并分析了用电容ＮＬＴＬ产生高压冲击波脉冲的实施方法和结果。     

一种基于MMIC技术的宽带左手非线性传输线二次倍频器

本文首次报道了基于MMIC技术的左手非线性传输线宽带二次倍频器。理论上分析了左手非线性传输线的二次谐波产生原理。在GaAs半绝缘衬底上制作了4节左手非线性传输线,面积为5.4mm*0.8mm。当输入信号为20dBm时,该倍频器在26.4GHz处获得最大二次谐波输出功率为6.33dBm,对应的-6dB带宽为24GHz~43GHz。实验结果与仿真结果吻合良好。以低频放大器作为激励,该倍频器可用于低成本,有效的毫米波甚至THz信号源系统。     

超宽带雷达系统中皮秒级脉冲源的研制

提出一种新型超宽带雷达高斯脉冲信号产生电路的设计方法,该电路利用微波三极管的开关特性和阶跃恢复二极管的阶跃特性,以及电容的充放电过程产生高斯脉冲信号,利用ADS软件对脉冲产生电路进行了仿真与分析。测量结果表明,该电路可以产生脉冲宽度400ps,重复频率1MHz,幅度4.1V的窄脉冲信号,且脉冲振铃很小,与仿真结果基本吻合,从而验证了该方法的合理性。该电路通过调节充放电电容的值实现脉冲幅度可调,当重复频率提高至10 MHz时,可得到3V～8V的幅度可调皮秒级高斯脉冲。该脉冲源能够满足超宽带雷达系统不同的应用要求。     

Low Spurious, Broadband Frequency Translator Using Left-Handed Nonlinear Transmission Line

In this letter, we present a frequency translator based on a left-handed nonlinear transmission line (LH NLTL). The proposed LH NLTL can achieve a very linear phase variation as a function of applied dc bias for a broadband frequency that facilitates a low spurious, broadband frequency translation. Our experiment demonstrates that the LH NLTL enables frequency shift with 30 dB maximum spurious suppression. For any frequency between 3 and 3.8 GHz, it was possible to achieve 100 KHz-1 MHz frequency shift while the range of spurious suppression is between 21 and 30 dB. Because of its compactness and possibility of low-cost monolithic fabrication, this circuit will be very useful for microwave instrumentation, or a coherent communication system where single sideband modulation is required.     

Subnanosecond pulse generation in the VUV by dual-wavelength pumpedstimulated rotational Raman scattering

A novel scheme to generate a subnanosecond pulse in VUV spectral region is proposed, by applying a dual-wavelength pumping method in conjunction with polarization switching technique to the stimulated rotational Raman scattering process. Optimum conditions for the efficient conversion and short pulse generation are presented through numerical model calculations. It is theoretically shown that the duration of the first anti-Stokes pulse of a VUV pump laser can be shorten to 0.72 ns. Since the anti-Stokes pulse is generated at a frequency within the gain profile of the pump laser, the proposed process is applicable to a seed pulse generation for subnanosecond pulse amplification by the pump laser medium in the VUV region