通信系统

In order to realize automatic testing and fault diagnosis for radio station , an automatic test system based on PXIbus was designed, also, the design of hardware, software and fault diagnosis were discussed in detail, and the method of classificatory testing about radio was introduced.

为了达到对通信系统电台的自动化测试和故障诊断的目的，设计了基于PXI总线的电台自动测试和故障诊断系统，详细说明了系统的硬件和软件组成以及故障诊断方法，并介绍了有关电台分级检测的方法，经验证此系统能够很好地完成电台的自动化测试与故障诊断并达到了设计要求；此系统的研制成功，充分说明了PXl总线系统在通信设备检测方面的巨大优势，为研制新一代的自动化测试系统指明了方向。

A structure of space-time diversity virtual double-route weighting interference mitigating is proposed, and the corresponding practical algorithm is derived in detail using block matrix inversion formula and matrix inversion theory for mitigating interference signals from both other cells and other users of local cell in the DS-CDMA up-link communication case. Performances of such algorithm are thoroughly analyzed through simulation and analytical results. The up-link and down-link channel characters and their relationship of DS-CDMA communication system are thoroughly analyzed, and the relationship of space-time diversity weighting matrix between time division duplexing and frequency division duplexing these two different transmission ways is derived.

本论文深入地比较了DS-CDMA通信系统的上传情形与下传情形的信道特性及其它们相互之间的关系；深入地分析并得到了时分双工和频分双工两种不同的传输模式下的上传情形与下传情形的空时分集权系数矩阵之间的数量关系，从而使得能够利用在基站端所拥有的上传情形的空时分集接收权系数矩阵信息以及其他信息在基站端直接形成空时分集发射权系数矩阵；推导了下传情形移动用户接收机端的最优组合接收策略及其算法；进一步地，对时分双工传输模式下的下传情形的通信系统性能和频分双工传输模式下的下传情形的通信系统性能进行了深入的比较仿真研究。

Based studies were done on radiation spectrum, voltage to current character and modulation property of white LEDs when they are used as optical transmitters. Then the configuration and systematic design techniques are concentrated concerning white LED lighting source communication with numerical analyses and computer simulations done as well as high speed modulation techniques, visible light receiver design and means to alleviate inter symbol interference along with background noise problem.

在对白光LED用作通信光源时的光谱特性、伏安特性、调制特性等物理特性做深入分析的基础上，重点研究了白光LED照明光源通信系统的组成结构和系统设计，进行了数学计算分析模拟，并设计出了白光LED高速调制电路和可见光接收电路，并就如何削弱码间串扰和背景光噪声对通信系统的影响进行了讨论分析。

More specifically, expenses incurred by a communications terminal that communicates with a first mobile radiotelephone system and a second mobile radiotelephone system are controlled by storing first and second critical values which characterize a tariff structure of the respective first and second mobile radiotelephone communication systems.

具体地说，与一个第一移动无线电话系统和一个第二移动无线电话系统通信的通信终端承担的费用受所存储的表征第一和第二移动无线电话通信系统各自资费制的相应第一和第二临界值控制。

According to the model, the interference characteristic and communication performance of the stratospheric system were analyzed.

提出了一种平流层通信与地面蜂窝通信频谱共用的系统模型，并根据该模型分析了平流层通信系统所受干扰的特性以及此时的通信性能。

Based on it, a detailed discussion about network management functions of the stratospheric communication system was made. And the network management model based on simple network management protocol for this system was given.

在此基础上研究了平流层通信系统网络管理技术，阐述了平流层通信系统网络管理的要求和应具备的功能，并结合简单网管协议设计了平流层通信系统网络管理模型。

In order to effectively reduce the effects of multi-access interference on the performance of optical code division multiple access communication systems with intensity modulation and direct detection,according to group information, a novel kind of multi-access interference cancellation scheme based on fiber Bragg gratingused with two dimensional address code MPC/OOC is presented.

摘要在强度调制、直接探测的光码分多址通信系统中，为了有效克服并发用户数之间的多址干扰，提高系统的通信性能，根据组信息，针对由光正交码和修正素数码构成的扩时/跳频地址码MPC/OOC，提出一种基于光纤布拉格光栅的多址干扰消除方案，并详细分析了采用这种多址干扰消除方案的光CDMA通信系统的性能。

With the wider use of modern electronic war, the technology of anti-jamming communication becomes the sticking point of military command and fight. Because hybrid DS/FH spread spectrum communication systems combine the good features of both direct sequence spread spectrum and frequency hopped spread spectrum , they increase the interference rejection capability of the systems and are regarded as the most lifeful anti-jamming communication systems in the world.

随着现代电子战的广泛应用，抗干扰通信技术成为保证军事指挥和作战的关键，由于混合直接序列扩频/跳频扩频通信系统将直接序列扩频技术与跳频技术结合，集中了直接序列扩频体制和跳频体制的优点，提高了系统的抗干扰能力，成为国内外公认的最富有生命力的抗干扰通信系统。

Trunking communication system is a senior mobile communication system with strong commanding and distributing features, and it is one type of private communication systems.

所谓集群通信系统，是一种具有调度功能的高级移动通信系统，它属于专用移动通信系统的领域。

Its necessary to find a quick, reliable and static flat for the virtual communication system in order to ensure the trueness and reality, so the structuring of the system flat is the last key technique.

要保证虚拟通信系统的逼真性和实时性，就要寻找一个快速、可靠、稳定的平台来实现整个虚拟通信系统，虚拟短波／超短波通信系统平台的构建是关键技术之三。

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。