通信系统

IRVINE, Calif.— Toshiba America Information Systems Inc., Telecommunication Systems Division announced the availability of uMobility, a Fixed Mobile Convergence solution that expands the Unified Communications capabilities for enterprise users of Strata CIX VoIP business communication systems.

东芝美国资讯系统公司旗下通信系统事业部近日在位于加利福尼亚的Irivne发布了即将上市的搭载固定与移动融合解决方案uMobility产品，该方案将为企业用户部署Strata CIX VoIP企业通讯系统时进一步扩展其统一通信能力。

Lastly, the communication mode and the communication protocol of the communication system in DAS are discussed.

最后，论文讨论了配电网通信系统的通信方式和通信规约的选择，提出了一种基于Internet的通信方式。

However, transmission rate and bit error rate are fixed in some communication systems.

实际的通信系统一般要求传输速率和误码率一定，提出的算法就以最小化发射功率为目标，在发射端自适应根据MIM0系统各个空间子信道的增益来分配传输比特、发射功率，最终获得好的频谱效率，并在满足通信系统要求的前提下，降低发射功率。

Professional technical ability concerning correspondence engineering of control:A machine and a machine principle and application c++ the buider program design the spot the programmable preface machine a principle and application calculator correspondence the net distance controls to exchange the fiber-optic correspondence of the principle correspondence principle ambulation the correspondence modern correspondence system.

掌握的有关通信工程的专业技能：单片机以及单片机原理及应用 c++buider程序设计现场可编程序器件原理及应用计算机通信网程控交换原理通信原理光纤通信移动通信现代通信系统。

First, this thesis describes the non-ideal effect of frequency synthesizer on the performance of wireless communication system.

首先，本文系统研究了频率综合器中的非理想因素对无线通信系统的影响，并通过理论计算得出多模通信系统对频率综合器的指标要求，进而探讨了多模频率综合器的实现方案。

The development and significance of chaology are introduced firstly. The general requirement of communication system and the application potential in secure communication are expatiated. The chaotic secure communication methods home and abroad are also summarized, including chaos spread spectrum communication, chaos key-shifting, chaos parameter modulation, chaos masking, chaos CDMA. The exiting problems and development direction are also pointed out respectively.

介绍了混沌学的发展过程和意义，阐述了通信系统的一般要求和混沌在保密通信中的应用潜力，综述了国内外现有的混沌保密通信方法，其中包括：混沌扩频通信，混沌键控，混沌参数调制，混沌掩盖，混沌数字码分多址等五大类，指出了各自存在的问题和发展方向。

This dissertation comprehensibly researches the performance of hybrid DS/FH spread spectrum communication systems, operating in a combined additive white gaussian noise , multiple access interference, and channel fading, particularly operating in hostile interference (partial band interference and multitone jamming). At the same time, the dissertation investigates performance of forward error correction coding and diversity technology against channel noise.

本文以此为背景，较为详细地研究了在信道中出现各种噪声干扰（高斯白噪声、多址干扰和信道衰落），特别是敌方的人为干扰（部分带宽噪声干扰和部分带宽多频干扰）时，混合DS/FH扩频通信系统的性能，以及前向纠错信道编码和分集技术对混合扩频通信系统信道出现噪声干扰时系统性能的改进情况。

One of their crucial functions is to make up the error recovery due to the deteriorative channel transmission conditions, provide better links condition to the transmission control protocol of upper layer. Then, the study of RLC and MAC two layers retransmission mechanism is very important to whole wireless system.

这两层有一个重要的作用就是弥补无线通信系统中信道条件不理想或底层不理想造成的传输错误，为上层的传输协议提供性能良好的链路环境，提高上层数据业务在无线传输通信系统中的性能，因此研究RLC和MAC层的重传性能对整个无线传输系统是很重要的。

With respect to the exponential computation complexity of the optimal multi-user detection in CDMA systems,a sub-optimal multi-user detector based on evolution strategy for exonerating crossover operation and lowing computation complexity is proposed.

1引言CDMA通信及其关键技术是目前国内外移动通信研究的热点，但是CDMA通信系统中存在着固有的多址干扰，极大地限制了多址用户数或同样用户数条件下的通信质量。

The advanced and practicability of Global Position System, and its characteristic orientating exactly has be

全球定位系统的先进性和实用性，其精确定位的功能特点已在各行各业中得到迅速的推广和应用，另一方面，传统的、功能单一的通信技术手段，已经不能适应多种业务发展的需要，因此，从运用先进的全球卫星定位与计算机技术，利用通信系统、多种先进技术集成以及实用性等方面设计集成综合信息系统很有必要。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。