A Distributed Capacitance Analysis of Co-Planar Inductors for a CMOS QVCO with Varactor Tuned Buffer Stage

A quadrature voltage controlled oscillator (QVCO) topology exhibiting low power consumption and high phase noise performance at low supply voltages is presented. The QVCO buffer includes varactors to maximize the output voltage and minimize the current consumption. Microstrip theory and the principle of conservation of energy have been used to evaluate the distributed capacitances of symmetrical inductors to better predict the resonance frequency. The QVCO is implemented in a 0.25 m CMOS process from Agere Systems. The total current consumption including the buffer is 5.4 mA at 1.3 V supply, where of the QVCO uses 2.0 mA. The phase noise measures below –138 dBc/Hz at 3 MHz offset frequency over the 8.9% tuning range 1.715 GHz– 1.875 GHz.Niklas Troedsson (SM98) received the M.Sc. degree in electrical engineering in 2001, and the licentiate degree in circuit design in 2003, both from Lund University, Lund, Sweden. He is currently working towards the Ph.D. degree within the Department of Electroscience, Lund University, Sweden. His research interests include low voltage RF CMOS, integrated quadrature oscillators, and monolithic inductors.Henrik Sjöland (M98) received the M.Sc. degree in electrical engineering in 1994, and the Ph.D. degree in applied electronics in 1997, both from Lund University, Lund, Sweden. In 1999, he spent one year visiting the Abidi group at UCLA, Los Angeles, CA, as a Fulbright postdoctoral scholar. He is currently an associate professor at Lund University, Lund, Sweden. His research interests include the design and analysis of analog integrated circuits, feedback amplifiers, and RF CMOS. Dr. Sjöland is the author of Highly Linear Integrated Wideband Amplifiers (Kluwer, Boston, MA: 1999).     

meso－苯基四苯并卟啉锌的合成和光谱性能的研究

ｍｅｓｏ－苯基四苯并卟啉锌的合成和光谱性能的研究胡敏学，王夺元（中国科学院感光化学研究所，北京１００１０１）关键词ｍｅｓｏ－苯基四苯并卟啉，高温缩合反应，吸收光谱，振子强度，聚集作用四苯并卟啉（ＴＢＰ）及其金属配合物是一类新型的光敏性分子，其０－０跃...     

面向雷达应用的微波光子信号产生技术

信号源是雷达发射机与接收机的关键组成部分,其性能直接影响着雷达的探测能力。基于电子技术的信号产生在信号载频、带宽以及噪声等特性方面受到限制,难以满足未来高性能雷达对高载频、大带宽、低噪声信号源的需求。新兴的微波光子技术能利用光子学手段产生高质量微波信号,在雷达信号产生领域具有广阔的应用前景。本文主要介绍利用微波光子技术产生雷达信号的研究进展,包括基于光电振荡器的高性能本振信号产生、线性调频信号产生和相位编码信号产生。通过对以上技术的分析发现,基于微波光子技术的微波信号产生具有带宽大、抗干扰等突出优点,是解决当前雷达信号产生技术瓶颈的有效手段。     

微弱正弦信号混沌检测的仿真分析

研究了一种在噪声背景下用混沌振子检测微弱正弦信号的时域处理方法。分析了基于相平面变化进行微弱正弦信号检测的Duffing方程的数学模型,着重对与策动力频率不同的信号进行了仿真分析。结果表明:Duffing振子对与系统策动力频率一致的信号敏感,而对其它频率的信号不太敏感,且对噪声具有一定的免疫力。     

基于频差控制的自适应频率检测研究

采用低阶Duffing混沌振子和高阶R(o)ssler混沌控制相结合,提出基于频差控制的微弱光电信号自适应频率检测的新方法,该方法通过对待检信号的频率与周期策动力频率之间频差的控制,实现了两种混沌振子之间的自适应选择,从而提高了检测精度和检测速度.该方法突破了以往Duffing方程检测信号频率需要使用较多混沌振子的局限,同时,也克服了高阶Rossler混沌控制检测方法中存在的检测速度慢的缺点,利用频差控制实现两种混沌振子的自适应选择,实现了微弱光电信号的频率检测.通过数值仿真和实验研究,验证了该方法的有效性.     

基于Duffing振子的梯形增幅波弱信号检测*

针对引信产品测试中的非周期梯形增幅波信号提出了基于Duffing振子的梯形增幅波弱信号检测的新方法。该方法利用梯形增幅信号的特征进行分段预处理,将非周期信号的检测转换为Duffing振子的准周期信号检测,避免了低信噪比下基于Duffing振子的微弱非周期信号检测受混沌振子检测机理的限制这一难点。仿真实验证明,该方法有效地检测出了低信噪比下的微弱非周期梯形增幅信号。结果表明,该方法能有效检测出引信测试中的梯形增幅波信号,并对零均值色噪声具有较强的抑制能力。     

基于混沌的LFM信号检测与参数估计

为了实现线性调频(LFM)信号的检测与参数估计,提出一种基于混沌理论的新算法.该算法首先分析了LFM信号参数变化对处于混沌临界态的Duffing振子输出相图的影响,并对待检LFM信号进行解调频处理.利用Duffing混沌振子构造滤波器阵列,以最大Lyapunov指数的符号作为系统状态的判断标准,从而实现了LFM信号的检测和参数估计.数值模拟表明,该算法易于操作,在低信噪比下,能有效检测LFM信号并获得较好的参数估计精度.     

The design and analysis of dual control voltages delay cell for low power and wide tuning range ring oscillators in 65 nm CMOS technology for CDR applications

In this paper three delay cell structures used in four-stage ring oscillator are evaluated. In the first structure, the control voltage is employed to the gate of PMOS transistors which are inserted in series with the input PMOS transistors. In this case the minimum power dissipation is gained. Since the control voltage is injected to the PMOS transistors parallel with input transistors, the better tuning range in higher frequency and lower phase noise is achieved. In order to make a tradeoff between the tuning range, phase noise and power dissipation, the PMOS transistors activated with the control voltage are applied to the oscillator in both the series and parallel paths. In improved structure, the oscillator works in 2.65–13.93 GHz under 1 V supply voltage in 65 nm CMOS technology. The phase noise is −94.33 dBc/Hz at 1 MHz offset from 3.7 GHz center frequency, while the power dissipation is 328.6 μW and the chip area is 139.5 µm².     

基于栅极电感反馈的CMOS差分Vacker VCO设计

提出了一种基于栅极电感反馈的Vacker压控振荡器(VCO),该结构能够改善电路的负阻抗,进而使得电路易于起振。对晶体管的负载效应和振幅稳定性的分析表明,该Vacker VCO相比较于Colpitts VCO,具有更好的振幅稳定性,进而改善了VCO的相位噪声。基于0.13-μm RF CMOS工艺,对该Vacker VCO进行了设计与芯片实现,测试结果表明：在消耗4.2 mW功耗的前提下,该VCO振荡频率为11 GHz～12.6 GHz,在11.8 GHz振荡频率处,相位噪声为-115.1 dBc/Hz@1 MHz,品质因数FOM指标达到-190.3 dBc/Hz。     

单片CDCTA-C低功耗电控调谐双模式三阶正交振荡器的设计

针对振荡器功耗大和振荡频率低的问题,提出了一种基于电流差分级联跨导放大器的三阶正交振荡电路.该电路仅使用一个电流差分级联跨导放大器和三个接地无源电容,可以同时产生两组等幅正交电流信号和一组等幅正交电压信号.电路结构简单,功耗低至1.8mW,最大灵敏度绝对值仅0.5,振荡频率可达10MHz数量级,而且振荡条件和震荡频率可相互独立地电控调谐.计算机模拟和流片芯片测试结果验证了理论分析的正确性.