利用SBS调Q的铒玻璃激光器模型

文章在前人的工作基础上,建立了适合于研究用受激布里渊散射（ＳＢＳ）进行调Ｑ的铒玻璃激光器的理论模型。利用该模型可以研究激光器的输出功率、脉冲宽度等特性。     

卫星系统新技术--应用机遇及发展策略考虑(上)

结合市场导向下的技术驱动重要性，重点论述现代卫星系统新技术及其在中国的应用机遇和发展策略。     

基于广义周期性的单通道多分量正弦调频信号分离和参数估计

针对噪声条件下的单通道多分量正弦调频(SFM)信号,该文提出一种信号分离和参数提取方法。利用正弦调频信号的广义周期性进行奇异值分解,以求出分量信号的调制频率;通过离散点搜索,估计出分量信号的调频(FM)初始相位、调制指数及载频,并对这些估计值利用信赖域算法进行优化,减小误差;利用内积计算,估计分量信号的幅度和初始相位。此外,还利用自相关矩阵特征值分解估计混合信号的信噪比(SNR),并根据信噪比确定停止分解的阈值。在仿真与分析中,针对具体的信号详细说明了该方法的各步骤,并在不同信噪比条件下分析了该方法的参数估计精确度。     

无线电信号识别方法的研究

文章提出了小波分析与神经网络相结合的方法自动识别无线电信号的调制类型.文中分别用常规的方法和小波的方法提取信号的特征参数，送入RBF（Radial Basis Function）网络，按照样本距离最小的原则进行聚类，利用RBF网络的快速收敛性和较好的自适应性，实现对无线电信号的识别.仿真结果表明，采用小波与神经网络相结合的分类方法，能获得满意的识别率。     

Adaptive modulation recognition based on the evolutionary algorithms

Nowadays, the development of classification algorithms gives the ability to improve Automatic Modulation Recognition (AMR) effectively. This paper presents a novel modulation recognition algorithm based on clustering approach. Generally, we aim to distinguish multicarrier modulation OFDM from single-carrier modulations. In this regard, two statistics of the amplitude of the received signal are calculated at the output of a quadrature mixer as key features. The extracted features of training data points are submitted to the clustering algorithm, then, centroids for single-carrier and multicarrier modulations are assessed. Afterwards, each point of testing dataset is dedicated to its nearest centroid based on Euclidian distance and the recognition is accomplished. Simulation results demonstrate that the algorithm is beneficial in a wide range from low to high SNRs.     

Thermal Effects and Small Signal Modulation of 1.3-μm InAs/GaAs Self-Assembled Quantum-Dot Lasers

We investigate the influence of thermal effects on the high-speed performance of 1.3-μm InAs/GaAs quantum-dot lasers in a wide temperature range (5–50°C). Ridge waveguide devices with 1.1 mm cavity length exhibit small signal modulation bandwidths of 7.51 GHz at 5°C and 3.98 GHz at 50°C. Temperature-dependent K-factor, differential gain, and gain compression factor are studied. While the intrinsic damping-limited modulation bandwidth is as high as 23 GHz, the actual modulation bandwidth is limited by carrier thermalization under continuous wave operation. Saturation of the resonance frequency was found to be the result of thermal reduction in the differential gain, which may originate from carrier thermalization.     

红外线立体声播放系统

工作于红外线波段的发送和接收设备(俗称无线电红外线耳机),可作为优质音响设备的延伸和功能扩展,本文为该系统的研制简报,并给出了样机的测试结果.     

变电站微机监测系统实现CDT远动通信的方法

本文详细地论述了利用变电站微机监测系统实现ＣＤＴ规约远动转发的硬件和软件设计，它使监测系统兼具ＲＴＵ功能，成为一个实时可靠，性能价格比高的综合自动化系统。     

非接触式静电电位测量系统设计

本文以静电电位测量系统的通用电路模型为基础，建立了调制型电位计的数学模型，分析了跌落系数、读数和误差与系统参数的关系；并讨论了设计方面的问题；为设计和评价静电电位计提供了理论和计算的依据。作者据此设计与研制的ＺＣ－１型静电电位计进一步验证了分析理论的正确性。     

低功耗高速硅电光调制技术的研究

通过对硅电光调制器研究结果的分析，提出厂低功耗高速调制的新技术。即采用不均匀掺杂人为引进漂移场和限制注入载流子运动范围以提高其浓度等方法，达到高速低功耗调制的目的。