MATLAB软件在通讯系统中的应用

随着时代的发展,通讯系统复杂性增加,传统的设计方法已经不能适应发展的需要,进行通讯系统模拟仿真的研究,开发一个高效的通讯系统模拟仿真环境已经成为目前的迫切需要。MATLAB是一种先进的程序设计语言,主要用于数值计算及可视图形处理。使用MATLAB语言的编程技术实现仿真技术的可视化,通过键盘操作就可以实现对通讯系统实现软件仿真。从而实现人机交流。讲述MATLAB软件的基本知识、发展历史及在通讯系统的应用。     

复杂系统计算机仿真的研究与设计

复杂系统与复杂性是21世纪的核心科学问题之一，并引入国家重点基础研究发展规划。基于复杂系统的复杂性和不确定性，很难想像可以采用传统朴素的还原论法进行可行性研究。推崇多智能主体的模糊计算机仿真来研究复杂系统的复杂性，并设计了一个基于多智能体的复杂系统分布仿真平台。     

基于成像球光强测量系统的光学设计

提出一种新的快速测量空间光强分布的方法,完成基于该方法测量系统的光学系统设计,并对光学系统的关键器件进行设计.利用Matlab编程和Solidworks三维建模得到自由曲面反射镜面型,Zemax光学软件设计优化得到双高斯物镜.光线追踪仿真软件LightTools对测量系统进行模拟仿真,验证系统的可行性,并对该构架下测量系统最小角分辨率和动态范围的关键性能指标进行分析.结果表明,设计的基于成像球的测量系统可实现空间光强分布测量.     

动态参数摄动系统可视化建模及群仿真研究

研究了动态参数摄动系统的可视化群仿真环境的软件实现问题，研究表明，应用先进仿真技术，采用面向结构化设计方法，即可实现参数摄动条件下的交互式可视群仿真。     

基于虚拟仿真技术的灌装生产线设计与仿真

目的 针对灌装生产线的设计与验证过程,基于虚拟仿真技术,实现灌装生产线的快速设计与验证。方法 首先通过分析灌装生产线的生产过程,利用SolidWorks三维建模软件分别对灌装生产线中的灌装机、搓盖机、贴标机、喷码机、装箱机等设备设计三维模型。然后将所有设备的三维模型导入Demo 3D仿真软件,进一步按照各设备的动作流程对模型进行动作设计及运动规划,构建灌装生产线虚拟仿真系统。最后根据设备功能和生产产能要求,在虚拟仿真系统中通过不断地调整设备机械结构及机构的运行速度,最终实现灌装生产线的快速设计与迭代优化。结果 得出灌装生产线的优化设计方案,并根据该设计方案研制出灌装自动生产线,生产线的产能为2400 瓶/h,满足企业要求。结论 该方法能够实现灌装生产线的快速设计与验证,缩短设计开发周期,减少设计和验证成本。     

浅析轨道交通仿真软件及应用需求

发展城市轨道交通是缓解城市交通拥堵,提升公共交通服务水平的重要举措。轨道交通仿真技术可为城市轨道交通规划、设计、建设、运营和维护的全生命周期提供有力的决策支撑。该文首先阐述了轨道交通仿真的基本流程,其次针对目前国内外典型的轨道交通仿真软件,在软件的功能和特点上进行了比较分析,最后重点探讨了轨道交通仿真技术在城市轨道交通领域的应用需求。     

基于ADS的射频通信系统教学研究

针对目前的射频通信系统教学中出现的系统概念不易理解和建立,分析介绍了ADS软件图形化的各类仿真分析方法,指出基于通信系统EDA软件ADS进行射频系统分析设计的教学是解决问题的有效方案。通过在Ptolemy环境中,代入DSP算法并建立收发射频系统进行BER（误比特率）仿真,展示了基于ADS进行射频数字通信系统的全系统仿真过程。     

基于4D CAD的大型桥梁施工进度系统仿真研究

随着桥梁建设的发展，传统横道图与网络图已成为施工管理水平提高的制约因素。将面向对象的复杂工程系统仿真方法与CAD数字建模方法相结合，将桥梁的3D整体模型和施工进度相链接，提出了基于4D CAD的桥梁施工系统仿真思想，使施工过程的动态可视化与直观分析优化后的施工进度成为可能。以Visual C++作为仿真平台，设计编制了桥梁施工4D CAD可视化仿真软件。研究成果在某斜拉桥工程施工组织设计中得到成功应用，验证了基于4D CAD的大型桥梁可视化仿真方法在斜拉桥施工进度分析与优化方面的实用性和优越性。     

基于仿真技术的单片机实验教学研究

本文提出在单片机课程教学的实验教学环节中引入仿真技术，利用软件Proteus进行电路分析与单片机程序仿真，从硬件搭接、程序设计以及软件硬件联合调试三个阶段阐述了基于仿真技术的单片机实验教学方法，指出了仿真技术的引入大大提高了单片机实验教学的质量和效率，为创造性学习活动提高了合适的环境。     

实时分布仿真环境下视景仿真系统的构建

随着仿真技术、计算机技术和网络技术的飞速发展,复杂系统仿真的应用领域不断扩大,对仿真过程的直观性、交互性和逼真度的需求日益提高.实时分布仿真环境下的视景仿真技术是仿真技术研究中的一项关键技术,因此对其进行研究具有重要的意义.对实时分布仿真环境下的视景仿真技术进行研究.分析实时分布仿真环境下视景仿真技术的需求,设计在实时分布仿真环境下视景仿真系统的构建,确定可行的软、硬件开发环境.     

Ergodic Capacity Evaluation of Multi-Hop Decode-and-Forward MIMO-OFDM Relaying Network

Spatial diversity plays a significant role in wireless communication systems, including the Fourth Generation (4G) and Fifth Generation (5G) systems, and it is expected to be a fundamental part of the future wireless communication systems as well. The Multiple-Input Multiple-Output (MIMO) technology, which is included in the IEEE 802.16j standard, still holds the most crucial position in the 4G spectrum as it promises to improve the throughput, capacity, spectral, and energy efficiency of wireless communication systems in the 2020s. This makes MIMO a viable technology for delay constrained medical and health care facilities. This paper presents an approximate closed-form expression of the ergodic capacity for the Decode-and-Forward (DF) protocol MIMO-Orthogonal Frequency Division Multiplexing (OFDM) relaying network. Although MIMO-OFDM is highly valuable for modern high-speed wireless communication systems, especially in the medical sciences, its performance degrades in multi-hop relay networks. Therefore, in this paper, an approximate closed-form expression is derived for an end-to-end ergodic capacity of multi-hop DF MIMO-OFDM wireless communication system has been presented. Monte-Carlo simulations are conducted to verify the performance of the presented analysis regarding the capacity (bits/s/Hz) for different SNR-dB values for single, 2 × 2, 4 × 4, and multi-hop DF MIMO-OFDM systems. The presented results provide useful insights for the research on the end-to-end ergodic capacity evaluation.     

采用电动式激振器的混合试验系统设计

混合试验是一种将数值模拟与物理试验相结合的新兴结构抗震试验方法,是一种评估非线性结构和系统性能的先进试验方法。该文提出了一种采用电动式激振器的混合试验系统设计方法。该方法以电动式激振器为作动器,并采用MATLAB软件、STM32系列单片机、串口通信技术、等效力控制方法以及位移传感器、力传感器等构建了一套包含硬件和软件的完整的混合试验系统。为了检验所设计混合试验系统的性能,选用粘弹性阻尼器作为试验子结构,对加入粘弹性阻尼器的单自由度框架结构进行了混合试验分析,结果表明:该文设计的混合试验系统数据通信可靠,整个系统可行、有效。     

应用MATLAB通信工具箱的频率合成器系统分析与仿真

介绍了MATLAB通信工具箱，针对通信系统仿真的特点，结合锁相环技术，给出了频率合成器的系统仿真模型，同时给出了系统仿真中的关键参数及设置参数的原理，结合仿真结果，具体讲述了仿真的目的和效果。     

CDMA卫星移动通信系统多重信号接收及其软件化实现

提出了一种适于卫星移动通信系统的CDMA多重接民协议,对其进行了原理分析并具体描述了其实现方式,同时,将软件无线电技术应用于该系统,给出了该协议的软件化实现方案,仿真结果表明,CDMA卫星移动通信系统多重信号接收其软件化是可行,并可应用于其它无线通信系统中。     

Rssi- and Lqi-based clustering: analysis and implementation of multihop EOP-LEACH for WSN using Sun SPOT

Network energy is the main constraint that affects the practical design of wireless sensor networks (WSNs) as the nodes have limited resource capabilities. This aticle presents a novel EOP-LEACH (Efficient Optimized Practical-LEACH) that is proposed to overcome limitations of conventional low energy adaptive clustering hierarchy (LEACH) protocol to improve the life time and reduce the energy consumption of the WSN. The proposed enhancement is achieved by inserting novel factors in the threshold equation of conventional LEACH in order to choose the optimum node to be Cluster Head (CH).. The novel proposed parameters to be inserted are the Received Signal Strength (RSSI) which is related to the communication pass distance and link quality indication (LQI) that reflect the effect of communication channel noise and interference. Multihop routing, based mainly on RSSI values of neighbor nodes, is another proposed improvement to conventional LEACH to decrease distance of transmission which leads to savings in network energy. The simulation of the proposed protocols was done using MATLAB software. Comparison between the performance of proposed protocols and conventional LEACH shows that the WSN performance is improved using the proposed protocols.     

实时频谱分析仪中CCDF测量功能的实现

实时频谱分析仪可以对通信信号进行实时测试,符合现代通信分析仪的发展趋势。CCDF测量是实时频谱分析仪的关键技术之一,对于测量多载波信号非常有用。它普遍应用在2G和3G无线信号测量上。本文介绍了实时频谱分析仪的总体框架,重点阐述了CCDF测量功能的原理和处理流程。并以OFDM系统(正交频分复用)为应用背景验证了这种算法的有效性。     

ZigBee技术的汽车胎压监测系统设计

针对目前直接主动式汽车胎压监测系统处理器与射频芯片分开设计、433 MHz无线频率造成的系统体积大、无组网、抗干扰能力弱等关键技术问题,设计了一种基于无线传感器网络的直接主动式汽车胎压监测系统.其中系统采用ZigBee首款SOC单芯片CC2430,无线通信频率为2.4 GHz.软件设计上改进了ZigBee通讯协议CSMA/CA机制,这样既能有效避免各轮胎监测节点发送数据的冲突,又能降低系统能耗、延长网络寿命.该系统能够实时自动监测轮胎内部压力、温度等状态信息,从而有效地保障了汽车行驶安全.     

GRID-Based Power Measurement in Digital Wireless Communication Systems

The combined use of multitaper estimation and wavelet thresholding has proved to be a very powerful digital- signal-processing algorithm in achieving the true power spectrum of signals that are peculiar to digital wireless communication systems and in ultimately carrying out accurate and repeatable power measurements. Nevertheless, the induced computational burden is too heavy. This paper mainly shows that GRID, which is currently one of the key technologies in deploying global-scale computing infrastructures, can make the aforementioned algorithm enforceable in a real-time context. A GRID computing-based approach for power measurement in digital wireless communication systems is proposed, which allows high levels of accuracy and repeatability in a significantly reduced measurement time. After a concise outline of the measurement algorithm, all of the adopted hardware and software strategies are described in detail. Major results concerning performance assessment and actual measurements are also given and discussed.     

Analysis of UWB system capacity in a realistic multipath environment with coexistence constraints

Ultra-wideband (UWB) wireless technology is envisaged to play a key role in B3G wireless systems, guaranteeing very high bit rates, low power consumption, low costs and location capabilities. The availability of low cost and efficient devices makes UWB technology very competitive on the communications market. However, its worldwide acceptance mainly relies on coexistence issues because of the necessity of sharing the spectrum with other radio systems. The reduction, due to coexistence constraints, in the capacity of an UWB system in a realistic multipath channel is investigated. Link performance of an UWB system that exploits either partial or selective Rake combining at the receiver is evaluated over experimental impulse responses of an UWB indoor channel in an office building. Using these results, system performances are evaluated through a semi-analytical procedure in terms of outage probability and system capacity. Results on system capacity account for the limitations imposed by the current regulation, leading us to introduce the concept of `UWB systems limited by coexistence'     

Experimental Assessment of Modulated$S$-Parameters Reliability in Modeling and Testing Wideband Radio Frequency Amplifiers

The paper deals with modeling and testing of radio frequency (RF) amplifiers that operate with wideband signals, such as those involved in emerging wireless and/or wireline communication systems. The use of new parameters, i.e., the so-called modulated$S$-parameters, is particularly encouraged and supported. Differently from traditional$S$-parameters, their measurement no longer requires a sinusoidal signal as test stimulus but a digitally modulated signal of the same type with which the RF amplifier has to operate. The reliability of the new parameters is assessed through a number of experiments conducted on an RF amplifier, which is mainly addressed to very wide bandwidth industrial and commercial applications. Both sinusoidal and modulated$S$-parameters are evaluated, and their ability in describing the real performance of the amplifier when operating with typical wideband signals, such as those involved in third-generation (3G) communication systems, is compared.