单片机控制下的TEA CO_2激光器快速调谐系统研究

提出了一种新型的单片机控制下的TEACO2 激光器快速光栅调谐系统 ,介绍了调谐触发系统的设计、红外零位光电传感器的原理、步进电机的控制、控制软件的设计及实验研究。这是一种简单、实用的开环控制系统。     

船用导航雷达收发系统的设计

介绍了一种船用导航雷达收发系统的设计,阐述了船用导航雷达的工作原理与系统构成,论述了收发系统的设计方法和工作原理,给出了调谐控制、灵敏度时间控制、射频控制单元的电路设计。     

复合型短波天线调谐器的设计

针对现代短波通信对天线调谐系统在调谐精度与速度方面的更高要求,提出一种复合型快速短波天线调谐的方案。讨论了基于驻波比和幅值的复合检测原理,阐述了该复合型天调的硬件设计及其实现方法,完成了基于CPLD的测频模块和结合查表法的嵌入式系统的软件控制模块的设计。测试结果表明,通过同时监测谐振幅值和电压驻波比复合参数,提高了调谐精度,调谐时间也得到改善,初步实现了对匹配网络的自动调谐控制。     

数字调谐收音机的生产工艺及调试技术

一、前言数字调谐系统是盒式收录机收音部分的一种新技术。数字调谐是电子调谐系统的一种。电子调谐是电子控制施加于接收机天线回路及振荡回路中变容二极管直流电压进行调谐的,只要改变反向偏压的大小,就能改变回路的谐振频率实现电子调谐,同时由于回路的反向控制电压相同,变容二极管极性相同,当电压变化时,结电容亦相应同步变化,从而达到了同步调谐的目的。发展至今的锁相环频率合成器的数字调谐接收机是在电子调谐系统上逐步发展     

宽调谐光纤激光器在温度传感中的应用

设计实现了一种编程扫描宽调谐掺铒光纤激光器,波长扫描调谐范围超过51nm(1516.83—1568.31nm),调谐步长最小可达0.01nm,通过编程控制波长重复扫描调谐。将该激光器应用于光纤光栅组成准分布式温度传感系统,初步实验实现了对16路共48个点的实时温度监测。     

数控电调带通滤波器的设计与制作

设计了一种新型电调谐带通滤波器,研究了数字信号控制滤波器电调谐的技术。采用数模转换器和高压运放实现数字信号与直流电压的转换;以变容二极管作为调谐元件;带通滤波器采用梳状微带线结构,并给出了结构参数。最后制作了一个由8位二进制编码控制的电调谐带通滤波器,其中心频率在300～1200MHz可调。测试结果与理论设计基本吻合。     

低频RFID室外天线调谐技术研究

低频RFID系统在实际应用中进行调谐存在一些问题,文章通过对低频RFID调谐原理的研究,提出了一种更加适用于实际应用的调谐方案,并通过实际的应用设计对调谐方案进行了验证。     

短波发射机自动调谐系统改进

笔者在分析目前短波发射机现有的调谐方式工作原理的基础上,介绍了跟踪频率自动调谐系统的控制原理及电路的设计框图,分析了以跟踪频率自动调谐方式改进发射机的调谐系统的设计.该系统地改进,有效地提高了发射机调谐系统的可靠性和发射机的整体自动化水平,具有一定的实际应用推广价值.     

光栅选线TEA CO2激光快速调谐技术研究

已研制了一种新型的采用直驱交流伺服电机的光栅选线TEA CO2激光器快速调谐系统,介绍了该系统的构建和设计,包括激光器快速调谐系统的硬件构成、软件设计及系统的运行流程,并进行了初步的实验研究。     

一种LC型CMOS射频带通滤波器及其自动调谐

介绍了一种二阶可调谐CMOS LC型射频带通滤波器及与其匹配的压控振荡器设计.品质因数很高而且可以通过负电导发生电路调谐.目标频率由一组分立的亚波段组成,通过电容阵列来控制.仿真结果表明,滤波器采用TSMC 0.18 μm CMOS 工艺,工作电压3.3 V,中心频率调谐范围为2.05 Hz至2.38 GHz.文中简单介绍了锁相环自动调谐系统.为了与滤波器进行匹配,振荡器是基于滤波器的原型设计的,仿真结果表明它们匹配良好.     

Stability and distortion in tuneable low frequency sinusoidal oscillators

The theoretical principles involved in the design of tuneable oscillators are presented in the context of a practical design which generates a sinusoidal output with a constant amplitude and low harmonic content over the range 7-2500 Hz in three overlapping bands, each with a continuous tuning range exceeding 20 : 1. We introduce a figure of merit ζ, the product of the fractional amplitude variation on tuning and the fractional harmonic content, and show that ζ = LλδL/L where L is the insertion loss at the resonant frequency w, (essentially L = Q^-1) of the frequency selective element, δL/L its fractional variation on tuning and λ is a constant depending on the structure of the oscillator and of the amplitude control system. When a subsidiary low-pass control loop characterized by a time constant T, which influences the settling time, is used, λ is inversely proportional to w _o T.     

A high-linear wide-tunable CMOS transconductor for video frequency applications

In this paper a new CMOS transconductor structure based on a g_m-boosted degenerated differential pair is presented for applications in the video frequency range. The proposed circuit combines two techniques, a switchable array of source degenerating MOS resistors and a programmable output current mirror, in order to widen the G_m tuning range while maintaining linearity. Degeneration MOS resistors are made common-mode voltage independent thanks to a simple control circuit. Post-layout simulation results from a 0.35 μm design supplied at 3.3 V show a wide tuning range (10–100 MHz), good linearity (−58.4 dB for an output signal voltage of 1.1 V_p–p) and low excess phase (<0.5° over the whole tuning range).     

Design formula for band-switching capacitor array in wide tuning range low-phase-noise LC-VCO

A low phase noise with wide tuning range complementary LC cross-coupled voltage control oscillator (LC-VCO) using 0.18 μm CMOS technology is presented. This paper proposes a design formula for the choice of the value of varactor (ΔC_var) and band switch capacitor (C_s) for the binary-weighted band-switching LC tank which is convenient to determine the proper tuning constant for wideband, low-phase-noise operations. This general formula considers the ratio of frequency overlap (ov) and all the parasitic effects from band-switching capacitor array and transistors. The designed VCO using a 4-bit band-switching capacitor array demonstrates the operating frequencies from 4.166 to 5.537 GHz with an equivalent tuning bandwidth of 28.26%. The measured tuning range of all sub-bands is well agreed with that of the post-layout simulation results. The measured phase noise is −123.1 dBc/Hz at 1 MHz offset in the 5.2 GHz band. The calculated figure-of-merit (FoM) of this VCO was as high as −187 dB. When considering the tuning bandwidth the designed VCO obtains a FoM-bandwidth product of 52.83, which is much better than previously published works.     

网络化控制模型的设计

文章首先介绍了网络化控制技术模型装置的设计,分别阐述了控制实验模型的整体设计和以太网控制系统的设计.上层监控软件采用LabVIEW图形化开发环境设计.然后针对参数整定过程中出现的困难,提出了将神经网络模糊PID自整定技术应用到该系统中的方案.该模型装置包含了工程应用中许多控制参数,可以满足不同程度的仿真实验和研究需要.     

网络化控制技术模型装置的设计研究

介绍了网络化控制技术模型装置的设计,分别阐述了控制实验模型的整体设计以及现场总线控制系统和以太网控制系统的设计。上层监控软件基于LabVIEW图形化开发环境。提出了用神经网络模糊PID自整定技术解决控制系统参数整定的问题的方案。     

1.5-V square-root domain second-order filter with on-chip tuning

A novel square-root domain (SRD) second order filter with automatic tuning control is described. The tuning system is based on a master-slave configuration, where the master is a SRD current-mode magnitude locked loop. The control circuitry allows tuning of the cut-off frequency as well as the quality factor and gain of the filter. The basic building blocks of the complete system are implemented employing a design strategy based on the inherent nonlinear characteristic of Class-AB linear transconductors. A proper biasing scheme in such transconductors leads to operation with very low supply voltages (as low as V/sub GS/+2V/sub DSsat/). Simulation and numerical results together with measurements from a fabricated prototype in a 0.8-/spl mu/m CMOS technology are included in order to validate the design technique proposed.     

基于Matlab的PID温度控制系统设计

PID控制是经典的控制理论,同时也是现今应用最为广泛的控制方法。文中以油冷却器的温控系统为研究对象,通过系统辨识和经典的PID参数整定法则,应用Matlab软件设计了系统的PID控制器。经过仿真,验证了该控制器达到了设计要求。     

可调谐激光器波长控制

文章介绍了可调谐激光器的波长调节及稳定控制的设计方法,并通过试验验证了其可行性.该设计由温度控制、偏置电流控制及锁波电路3部分组成,温度控制粗调波长,偏置电流控制微调波长,而锁波电路主要是针对外界温度发生变化时提供反馈.它适用于温度控制型分布反馈式 (DFB)可调谐激光器的外围电路设计.