基于注频锁相振荡器阵列的多波束扫描技术

研究了利用注频锁相振荡器阵列实现非线性有源天线阵多波束扫描技术,给出了注频锁相振荡器阵列的拓扑结构及相位动力学方程组,建立了基于注频锁相振荡器阵列的多波束天线加权模型并详细分析了加权矩阵的确定方法,最后对直线阵和矩形平面阵多波束扫描的方向图进行了计算机仿真并搭建了两波束扫描实验系统,进一步验证了该技术的可行性.     

注频锁相振荡器阵列的低相位噪声信号产生方法

提出了注频锁相振荡器阵列的拓扑结构及相位噪声模型,根据该模型简要推导了注频锁相振荡器阵列相位噪声的计算公式并对整个阵列的相位噪声进行了分析,完成了1×4单元注频锁相振荡器阵列相位噪声的测试,测试结果与理论分析吻合,最终得出了注频锁相振荡器阵列的低相位噪声信号产生方法。     

非线性有源天线阵多波束相位分布控制方法

研究了基于注频锁相振荡器阵列的非线性有源天线阵多波束拓扑结构模型,详细分析了一维线阵、二维面阵多波束相位分布的控制方法并完成了一维线阵、二维面阵的相位分布仿真和方向图仿真,验证了该方法的有效性。最后,完成了多波束性能的分析。     

有源天线阵波束电扫描新技术

研究了利用互注频锁相技术实现的低成本、高集成度、高效率的新型非线性有源天线阵列,给出了耦合振荡器阵列的幅度及相位动力系统满足的微分方程组,然后针对控制非线性有源天线阵列波束扫描这一实际应用,找到了可以实现有源天线阵列波束扫描的相位动力系统的轨道及振荡器自由振荡频率需满足的条件,并对轨道的稳定性进行了分析,提出了一种不用移相器实现非线性有源天线阵列波束电扫描的方法,最后利用计算机仿真验证了该方法的可行性.     

基于注频锁相和非线性振荡器的接收波束形成

本文提出以注频锁相技术为基础接收窄带信号的非线性振荡器波束形成器,给出了注频锁相现象的Adler方程及非线性振荡器的动力微分方程.并提出了零陷多波束形成算法,推导权矢量,并通过仿真分析该算法的信号波达图效果.     

矩形耦合本振阵列接收波束形成

分析了耦合振荡器阵列的波束接收原理,以二维矩形耦合振荡器阵列为本振阵列,推导了产生均匀平面相位分布的控制方法,确定了波束形成的相位加权矢量,并通过仿真验证理论分析结果,为耦合振荡器阵列在天线接收技术的应用提供理论参考.     

基于注频锁相技术的接收天线本振阵列

文中以注频锁相技术为基础,提出一维和二维注频锁相耦合本振阵列基本结构,分析了注频锁相本振阵列的相位动力学方程,推导了稳定同步状态本振信号间的相对相移与振荡器自由振荡频率的关系,为注频锁相技术在接收天线本振阵列的应用提供理论基础.     

相位加权实现多方位合成波束的研究

在空域多个任意方位同时合成波束有利于数字阵列雷达多功能、多任务的实现.文中介绍了相同信号在空域多个方位合成波束的原理和目前采用饱和功放发射需解决的问题;在此基础上提出了用相位加权解决这些问题的方法,最后通过仿真对正常发射、相位加权方法和改进相位加权方法发射的波束主瓣增益进行了对比,验证了该方法在保持副瓣性能上的有效性与工程实现的可行性.     

超指向性相控阵列波束形成设计与实现

超指向性相控阵列设计要求阵列具有高指向性,基于对平面阵波束形成与指向性的理论分析,提出了矢量分解阵列设计,使波束形成的方法得到很大的改进,并实现相控阵系统中各阵元发射和接收相位的精确控制.     

非线性有源天线阵接收技术研究

利用注入耦合振荡器阵列直接实现非线性接收波束合成,具有旁瓣低的优点,但难以实现接收波束扫描.因此提出了一种非线性有源天线阵接收的新技术,采用耦合振荡器阵列作为本振对接收信号进行混频,在中频进行波束合成.由于阵列单元间相位差可控,能实现接收波束扫描,还可用于生成和差接收波束.实验表明该技术可用于构建非线性有源天线阵的接收系统.     

基于耦合振荡器阵列的非线性有源天线阵

利用耦合振荡器阵列实现有源集成天线阵电扫描,可以实现相控阵天线高效率、低成本、小型化。文中利用Y-参数对利用任意耦合网络实现的耦合振荡器阵列进行了分析,得到了系统幅度及相位非线性动力系统的微分方程组,然后针对利用耦合振荡器阵列实现非线性有源天线阵列这一实际应用,提出了一种不用移相器实现有源天线阵列波束扫描的方法,并进行了稳定性分析。最后利用计算机仿真验证了该方法的可行性。     

星载合成孔径雷达有源相控阵天线研究

该文从雷达工作模式、模糊度、分辨率及信噪比等几个方面研究了星载合成孔径雷达的有源相控阵天线波束调节方式和波束赋形特点,设计了一种适合于二条带高分辨率扫描模式星载合成孔径雷达的有源相控阵天线,该文还研究了有源相控阵天线的可靠性问题,提出一种利用冗余设计提高天线可靠性的方案。     

Balanced monolithic oscillators at K- and Ka-band

A technique for generating accurate antiphase signals is presented in this paper. Monolithic oscillators at 20 and 40 GHz are realized using this technique. These oscillators have dual outputs that are mutually locked in antiphase. The inherent amplitude and phase balances between the output signals are verified. This is achieved by direct measurement using injection-locking polar diagrams, as well as low-frequency measurements of the down-converted oscillator outputs. The operation of the balanced oscillator as a multidevice power-combining oscillator is also investigated. Improvements of phase noise reduction and frequency stabilization are demonstrated at the combined oscillator output. This new oscillator topology shows significant potential in balanced circuits like mixers, multipliers, and modulators where circuit performance relies on the precise generation of the balanced signals     

S波段大功率注入锁频磁控管的输出特性

在多路注入锁频大功率连续波磁控管的相干功率合成实验中,输出特性分析有利于提升合成效率。搭建了一款S波段20 kW连续波磁控管注入实验系统,该系统包含幅频可调的微波源和移相器,由磁控管信号发生系统、注入锁定系统以及相位差检测系统3个小系统组成。利用外部注入信号,分别对磁控管输出信号的相位稳定度、频谱和相位噪声进行实验分析,实现了对实际磁控管在外部注入前后的特性分析。其中,相位差波动最小不足4°,最大17°,锁频带宽在2.9~13 MHz之间变化,在偏移频率1 MHz内对相位噪声抑制超过40 dB;并对注入锁频信号与输出信号之间的关系进行了总结,为多路大功率磁控管的功率合成提供理论依据。     

A general theory of phase noise in electrical oscillators

A general model is introduced which is capable of making accurate, quantitative predictions about the phase noise of different types of electrical oscillators by acknowledging the true periodically time-varying nature of all oscillators. This new approach also elucidates several previously unknown design criteria for reducing close-in phase noise by identifying the mechanisms by which intrinsic device noise and external noise sources contribute to the total phase noise. In particular, it explains the details of how 1/f noise in a device upconverts into close-in phase noise and identifies methods to suppress this upconversion. The theory also naturally accommodates cyclostationary noise sources, leading to additional important design insights. The model reduces to previously available phase noise models as special cases. Excellent agreement among theory, simulations, and measurements is observed     

Jitter and phase noise in ring oscillators

A companion analysis of clock jitter and phase noise of single-ended and differential ring oscillators is presented. The impulse sensitivity functions are used to derive expressions for the jitter and phase noise of ring oscillators. The effect of the number of stages, power dissipation, frequency of oscillation, and short-channel effects on the jitter and phase noise of ring oscillators is analyzed. Jitter and phase noise due to substrate and supply noise is discussed, and the effect of symmetry on the upconversion of 1/f noise is demonstrated. Several new design insights are given for low jitter/phase-noise design. Good agreement between theory and measurements is observed     

Indirect optical injection-locking of multiple X-band oscillators

Experimental results of indirect optical injection-locking of two X-band oscillators are presented. An S-band master source is used to lock both oscillators over 18 MHz using the laser diode nonlinearities. System FM noise degradation is 14 dB and the means to improve system performance are suggested.     

Output Power and Loss Analysis of 2/sup n/ Injection-Locked Oscillators Combined through an Ideal and Symmetric Hybrid Combiner

The scattering matrix for an ideal (2/sup n/+1) port combiner, formed by interconnecting (2/sup n/-1) magic-tee hybrids, is developed. This matrix is then used to describe a coherent power-summing technique for 2/sup n/ injection-locked oscillators for n=3. The losses that arise from combining oscillators with different injection-locking characteristics are evaluated by two methods: 1) expressions for the output power and loss of the combiner as functions of the input signals are obtained with amplitude and phase as parameters; 2) a semigraphical solution for the combined output and loss is obtained by means of a flow chart and computer-generated gain, loss, and phase characteristics of a single-hybrid junction. The amplitude and phase balance required between individual oscillators for efficient power addition is described, giving the engineer a quantitative measure of the multiple-oscillator design requirements.