通信系统

with the development of satellite navigation communication,antenna is a very important unit,performance of the satellite navigation communication system is affected by it partly.a new type of bifilar helix for satellite navigation communication system is introduced,and the traving-wave bifilar helix is analyzed briefly.meanwhile,the design and the test results are given.the results show that the antenna possesses excellent circular hemispherical beam with wide angle circular polarization and better impedance match,and has a compact structure and high integration.it can be applied in caps systems successful.

小 摘要：随着卫星导航通信技术的迅速发展，天线作为卫星导航通信系统中的重要部分，在一定程度上决定着卫星导航通信系统的性能。介绍一种用于卫星导航通信系统的双臂螺旋天线，讲述爬行波式螺旋天线的设计过程，并给出最终测试结果。结果表明，该天线具有优良的圆对称半球波束，良好的广角圆极化特性和优良的阻抗匹配特性，其结构简单、紧凑，为通信入站回传提供了一种优良的选择。

Power control is one of the necessary key techniques for mobile communication systems. The frame structure of WCDMA communication system is different from those CDMA commination systems, which have only one type of traffics. In addition, multimedia services have different quality of service requirements. Thus the power control for WCDMA communication system will different from that in narrow band CDMA communication systems.

功率控制是CDMA移动通信系统中必不可少的关键技术之一，WCDMA移动通信系统的结构不同于单一业务的CDMA移动通信系统，且多媒体业务有不同的服务质量要求，因此，WCDMA多媒体移动通信系统中的功率控制将不同于单一业务的CDMA移动通信系统中的功率控制。

Circuit principles, analogue circuit, digit circuit which laid me a solid foundation of circuit for the study of communication; the study of electronic circuit of communication provided me with the working principles of analog communication system; the study on communication theory made me grasp the working methods of digital communication; the study on electromagnetic field, electromagnetic wave and aerial let me know that how signals travel through signal paths and how to apply signal and linear system, random signal and system to the research of noise's impact on signals

学习了电路原理、模拟电路、数字电路打下了学习通信的电路基础；学习了通信电子线路掌握了模拟通信系统的工作原理；学习了通信原理掌握了数字通信的工作方法；学习了电磁场与电磁波、微波与天线了解了信号如何在信道中传输；学习了信号与线性系统和随机信号与系统来研究噪声对信号的影响。

It with wired compares mainly has the cost to be low, carries conveniently, omits the wired wiring the worry; Specially is suitable to grasping the equipment the correspondence, the battery power supply equipment, the vehicles monitoring, the remote control, the telemetering, the small wireless network, wireless copies the table, the system, the plot messenger call, the industry data acquisition system, the wireless label, the status recognition, must contacts the RF smart card, the small wireless data terminal, the safe fire protection is systematic, wireless domain and so on in external guidance system, biological signal gathering, hydrometeorology monitoring, robot control, digital audio frequency, numeral image transmission the low power loss, the microminiaturization is the current wireless correspondence product then takes along the product in particular the urgent need and the key question.

它与有线相比主要有成本低，携带方便，省去有线布线的烦恼；特别适用于手持设备的通信、电池供电设备、车辆监控、遥控、遥测、小型无线网络、无线抄表、门禁系统、小区传呼、工业数据采集系统、无线标签、身份识别、非接触RF智能卡、小型无线数据终端、安全防火系统、无线遥控系统、生物信号采集、水文气象监控、机器人控制、数字音频、数字图像传输等领域中。低功耗、微型化是当前无线通信产品尤其是便携产品的迫切要求和关键问题。无线通信的另一个关键问题是数据传输的可靠性，这取决于诸多因素，如频率选择、同频干扰、传输距离、天线选择等，这些在设计无线通信系统时都要认真考虑和比较。

In order to be able to transmit a variable volume of data, particularly in a single coherent data block, between message transmission planes of telecommunications interfaces of a hybrid telecommunications system with minimal effort within the message transmission planes, if the variable data volume exceeds the maximum data volume which can be transmitted between the same message transmission planes of the telecommunications interfaces, then a data element specific to the transmission layer is used as a function of the varying data volume at least twice in succession for the transmission of the data volume in the data block.

要約 为在混合通信系统中能各自以最小的传输工作量在各通信传输层面中传输混合通信系统各通信接口的通信传输层面之间的一个变化的数据量，尤其当此变化的数据量超过在各通信接口的相同通信传输层面之间最大可传输的数据量时仍能在一个单一的互相关联的数据块中传输此变化的数据量，取决于此变化的数据量至少两次依次地对在数据块中的数据量的传输采用一种传输层面专门的信息元素。

The main research issues of RRM on the circumstances of different standard wireless communication systems and various services are also discussed in the paper.

文章结合当前正在研究的后3代(B3G)、第4代(4G)移动通信系统的发展和处于运营及推广阶段的第3代移动通信系统，分析了未来移动通信系统中无线资源管理系统的关键技术，探讨了多体制标准下的无线通信网络和多种业务情况下的无线资源管理的研究方向。

The key technologies of radio resource management for future mobile communication system are analyzed, based on the development of B3G and 4G mobile communication systems and the third-generation mobile communication system. The main research issues of RRM on the circumstances of different standard wireless communication systems and various services are also discussed in the paper.

文章结合当前正在研究的后3代(B3G)、第4代(4G)移动通信系统的发展和处于运营及推广阶段的第3代移动通信系统，分析了未来移动通信系统中无线资源管理系统的关键技术，探讨了多体制标准下的无线通信网络和多种业务情况下的无线资源管理的研究方向。

The key technologies of radio resource managementfor future mobile communication system are analyzed, based on the development of B3G and 4G mobile communication systems and the third-generation mobile communication system. The main research issues of RRM on the circumstances of different standard wireless communication systems and various services are also discussed in the paper.

文章结合当前正在研究的后3代、第4代移动通信系统的发展和处于运营及推广阶段的第3代移动通信系统，分析了未来移动通信系统中无线资源治理系统的要害技术，探讨了多体制标准下的无线通信网络和多种业务情况下的无线资源治理的研究方向。

In order to realize the compatible communications system between digital TETRA and analogy MPT1327. Communications protocol between digital radio and control center is defined. Emergency call software flow for TETRA and MPT module is designed, and also state information sending and receiving for TETRA and MPT module is designed in this communication system. By comparing several solutions, switch methods between analogy TETRA communications and digital TETRA communications are designed including manual-switch and soft-switch. In the article, coding module of receiving and sending equipments in TATT analogy TETRA communications is described, so that it can be compatible with NOKIA network equipments and it also can improve the availability rate of the trunk system. In order to realize the integration of digital TETRA communication and analogy MPT1327 communications, double- frequency antenna system is researched.

通过几种车载电台解决方案比较，设计了相应的模拟集群通信系统与数字集群通信系统的切换方法，其中包括人工切换和软切换，实现了模拟与数字集群兼容的一体化移动列车调度电台解决方案；为了实现数字集群通信系统与模拟集群通信系统以及NOKIA与TAIT模拟集群通信系统之间的相互兼容，设计了新的数字车载电台与控制中心之间的通信协议；系统设计了用于数字集群通信模块的紧急呼叫通讯流程，以及设计了用于模拟集群通信模块状态信息发送与接收流程，以满足列车无线调度的运营要求；论文还论述了对TAIT模拟集群收发设备编码模块的改造，使之能与NOKIA的集群设备相兼容，提高了集群设备的利用率，为在NOKIA模拟集群通讯模块停产后寻找了一种可替代的兼容解决方案；为了实现数字集群通信系统与模拟集群通信系统设备的综合，论文还探讨了本工作所需专用的双频段的天线系统。

The system includes a plane-carried communication subsystem, a satellite communication subsystem, and a ground communication subsystem, wherein, the ground communication subsystem includes a first communication terminal, a second communication terminal, and a ground communication network. The ground communication subsystem also includes an incoming transfer subsystem. The first communication terminal's calling to the second communication terminal is transferred to the corresponding fixed satellite communication terminal through the ground communication network, the satellite communication terminal, and plane-carried communication subsystem according to the correspondence of incoming call transfer.

本发明系统包括机载通信子系统、卫星通信子系统和地面通信子系统，其中，所述地面通信子系统包括第一通信终端、第二通信终端、地面通信网，所述地面通信子系统还包括来电转接子系统，所述地面通信子系统中第一通信终端向第二通信终端的呼叫按照来电转接对应关系依次通过地面通信网、卫星通信子系统、机载通信系统子系统转接到对应的固定卫星通信终端。

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。