探讨移动电话及卫星通信中的关键技术

探讨移动电话及卫星通信中的关键技术随着电子通信技术的发展，它同时在很大程度上改变着人们的生活和方式。人们也能很好地运用电子通信技术突破时间和空间的局限来学习和工作。电子通信技术不仅改变着人们，它还在改变着社会和国家，使得国家不断发展，特别表现在卫星通信技术上。当然我国的电子通信技术还存在一些关键技术的问题，有待人们改善和加强。 With the development of electronic communication technology, it greatly changes peoples life and the way. People also can be a good use of electronic communications technology breakthrough the limitation of time and space to study and work. Electronic communication technology not only change people, it is still changing society and the state, the national development, particularly in satellite communication technology. Of course, electronic communication technology of our country also exist some key technology problem, need to be improved and strengthened.一、电子通信系统概述 An overview, electronic communication system电子通信技术属于现代通信技术中的一大部分。电子通信技术还是信息社会的主要支柱，是现代高新技术的重要组成部分，甚至是国家国民经济的神经系统和命脉。在现代化信息社会，电子通信技术无处不在，它涉及的范围也很广，包括移动电信、广播电视、雷达、声纳、导航、遥控与遥测以及遥感等领域，还有军事和国民经济各部门的各种信息系统都要运用到电子通信技术。 Electronic communication technology belongs to the most in modern communication technologies. The main pillar of electronic communication technology and information society, is an important part of modern high technology, and even the nervous system and the lifeline of the national economy. In the modern information society, electronic communication technology is everywhere, it involves a wide range, including mobile telecommunications, radio and television, radar, sonar, navigation, remote control and telemetry and remote sensing and other fields, there are all kinds of information system in military and all sectors of the national economy should be applied to electronic communication technology.电子通信系统中最具代表性也最常见的就是移动通信和卫星通信。其中移动通信就包括了卫星通信，此外还有蜂窝系统、集群系统、分组无线网、无绳电话系统、无线电传呼系统等多个领域。 Electronic communication system in the most representative and the most common is the mobile communication and satellite communication. The mobile communication includes satellite communication, in addition to the cellular system, cluster system, packet radio network, cordless telephone system, radio paging system etc.二、电子通信系统关键技术问题 Two, the key technical problems of electronic communication system近几年来，电子通信技术应用十分广泛，就其最具代表性的移动通信和卫星通信来看，就存在很多关键性的技术问题，有待加强和改善。移动通信技术在电子通信技术中发展范围最大最迅速，传统的蜂窝通信因为可用无线频谱资源的增加和无线信号的衰弱而变得越来越受局限。不断缩小的小区半径代表着基站的密度也在不断增加。除此之外，频繁的越区切换导致空中资源的浪费和频谱效率降低，这也使得网络建设的成本也是越来越高。从以上各种因素可以看出，要想获得更高的频谱效率和更大更充足的系统容量，就应该突破传统蜂窝体制，应用新的移动通信技术。 In recent years, the application of electronic communication technology is very extensive, is the most representative of the mobile communication and satellite communication, there are many key technology problems, to strengthen and improve. Mobile communication technology in electronic communication technology development the most rapid, cellular communication traditional because increasing the available radio spectrum resources and wireless signal becomes more and more limited. The cell radius shrinking represents the base station density are increasing. In addition, frequent handover to reduce waste and spectrum efficiency of air resources, it also makes the network construction cost is also more and more high. From the above various factors can be seen, in order to get higher spectrum efficiency and more adequate system capacity, should break through the traditional cellular system, the application of mobile communication technology new.1、移动通信系统关键技术问题 1, the key technical problems of mobile communication system在移动通信系统中采用分布式天线是很有效也很成功的一种方式，每个小区内都有很多个无线信号处理单元，这些单元距离都比载波波长要远得多，并且它们都能进行功放变频和信号预处理。要在核心处理单元实现信号处理的功能，首先就要完成信号的收发功能和一些简单的信号预处理，然后就要与核心处理单元连接，通过光纤和同轴电缆或微波无线信道来实现。有两种方式可以实现分布式移动通信，第一种就是在所有的无线信号处理单元上所有相同的下行链路信号同时发射，然后小区内的无线信号处理单元接收到上行链路信号之后直接传送到中心处理单元。这种方案优点是简单，缺点则是会不断干扰系统，阻碍了系统容量的扩大。第二种方式则是在整个业务区域内完成无线覆盖的分布式天线结构，通过用大量的无线信号处理单元来实现，酿酒设备从而突破传统蜂窝小区的理念。这种方式也可称之为“受控天线子系统”，即“仅与移动台相近的信号处理单元负责与移动台进行通信”的方式。第二种较之第一种更理想，但同时它也更复杂。In a mobile communication system using distributed antenna is a very effective way is also very successful, there are a lot of wireless signal processing unit in each cell, the unit distance than the carrier wavelength is much farther away, and they can power conversion and signal processing. In the core processing unit to realize signal processing function, we must first complete the signal transceiver functions and some simple signal preprocessing, and then to connect to the core processing unit, to achieve through the optical fiber and coaxial cable or microwave radio channel. There are two ways to realize the distributed mobile communication, the first is in all of the wireless signal processing unit, all the same downlink signals transmitted at the same time, then the area within the wireless signal processing unit receiving the uplink signal is directly transmitted to the central processing unit. This scheme has the advantages of simple, is constantly jamming system, expand the system capacity of the block. The second way is to complete the distributed antenna structure of wireless coverage throughout the business area, is achieved through the use of radio signal processing unit is large, which breaks through the traditional cellular concept. This method can also be called controlled antenna subsystem , namely signal processing unit is similar with the mobile station is responsible for the communication with the mobile station way . Second as compared to the first kind of more ideal, but at the same time, it is also more complex.分布式移动通信较传统的移动通信技术有几点优势，第一是小区间干扰低、SIR高且系统容量大，第二是它内部的分集能力不仅能用来抵抗阴影效应，还能够保证不衰落和扩大系统的容量。第三是它能全面提高其自身切换性能和接受信号的功率，海吉布还能降低其切换次数。第四是它对其他通信系统的干扰小并且在相同发射功率下覆盖的区域更大，反之其发射功率更低。第五是它不仅能更方便快捷地实现任意形状的无线业务服务区，还能核心处理单元集中处理信号。更能有效利用无线资源。 Mobile communication technology of distributed mobile communication than traditional has several advantages, the first is the inter-cell interference is low, SIR is high and large system capacity, the second is its internal diversity not only can be used to resist the shadow effect, but also can guarantee not to decline and expand the capacity of the system. Third is the power which can improve its switching performance and receive signals, can reduce the switching number. The fourth is its interference to other communication systems and is covered in the same transmit power larger area, whereas the emission power and lower. Fifth is the wireless service area, it not only can more quickly realize the arbitrary shape, but also the core processing unit centralized signal processing. More efficient use of radio resources.子通信系统分为5层：应用层、驱动层、传输层、数据链路层和物理层。这5层之间功能划分应明确，接口应简单，从而为硬软件的设计实现奠定良好的基础:应用层是通信系统的最高层次，它实现通信系统管理功能（如初始化、维护、重构等）和解释功能（如描述数据交换的含义、有效性、范围、格式等）。驱动层是应用层与底层的软件接口。为实现应用层的管理功能，驱动层应能控制子系统内多路传输总线接口（简称MBI）的初始化、启动、停止、连接、断开、启动其自测试，监控其工作状态，控制其和子系统主机的数据交换。传输层控制多路传输总线上的数据传输，传输层的任务包括信息处理、通道切换、同步管理等。数据链路层按照MILSTD一1553B规定。控制总线上各条消息的传输序列。物理层按照MILSTD一1553B规定，处理1553B总线物理介质上的位流传输。应用层、驱动层在各个子系统主机上实现，传输层、数据链路层、物理层在MBI上实现。 Communication subsystem is divided into 5 layers: application layer, driver layer, transport layer, data link layer and physical layer. This 5 layer between functional division should be clear, interface should be simple, and design for the hardware and software realization and lay a good foundation: the application layer is the highest level of communication system, it realizes the communication system management functions ( such as initialization, maintenance, reconstruction ) and explain the function (as described in definition, data exchange, the effective range the format, etc.). The driver layer is the application layer and the underlying software interface. In order to realize the management function of application layer, driver layer should control the multiplexed bus interface subsystem (MBI ) initialization, start, stop, connect, disconnect, start the self-test, monitoring the working state, control and host data exchange subsystem. The transport layer controls the data multiplexed bus, transport layer task includes information processing, channel switching, synchronization management etc. The data link layer in accordance with the MIL - STD 1553B. Transmission sequence control bus of each message. The physical layer according to MIL - STD 1553B, 1553B bus physical media on the bit stream transmission. Application layer, driver layer implementation in each subsystem of the host, the transport layer, data link layer, physical layer on the MBI implementation.2、卫星通信系统关键技术问题 2, the key technical problems of satellite communication system卫星通信在电子通信技术中最为先进，它也有很大的优势，包括通信距离远并且容量大，通信线路质量稳定可靠以及机动性能优越和灵活地组网等这些都是别的技术没有的特点。但随着不断快速发展的全球信息化产业，人们对信息的需求也越来越复杂多样，电子通信技术已进入高速、多媒体、业务多样化和可移动的个性化时代。 Satellite communication in electronic communication technology in the most advanced, it also has a lot of advantages, including the communication distance and large capacity, communication lines and stable and reliable quality and superior maneuverability and flexible networking, these are the characteristics of other technology without. But with the development of information industry has been rapid development, peoples demand for information is more and more complex and diverse, electronic communication technology has entered the high-speed, multimedia, business diversification and mobile personalized era.目前的卫星通信的一些关键技术也存在一些问题，它包括高速数据的业务需求。以及卫星通信应用宽带IP的难点。现代卫星通信技术采用一些关键技术来解决问题，一个就是数据压缩技术，它能让静态和动态的数据压缩都能有效提高通信系统在时间、频带、能量上的工作效率；第二个就是智能卫星天线系统；第三个就是宽带IP卫星通信技术的研究；第四个就是新型高效的数字调制及信道编码技术；第五个就是多址连接技术的改进和发展；第六个就是卫星激光通信技术。 Some key technologies of satellite communication is also exist some problems, which include high speed data business needs. And the difficulties of satellite communication application in broadband IP. Modern satellite communication technology uses some key technology to solve the problem, one is data compression technology, it can make static and dynamic data compression can effectively improve the work efficiency in time, energy band, the communication system; second is the intelligent satellite antenna system; third is the broadband IP satellite communication technology; fourth is a new and efficient digital modulation and channel coding technology; fifth is a multiple access technology improvement and development; sixth is the satellite laser communication technology.未来的卫星通信数据率会通过激光通信来实现，激光的优势会在互联卫星网中得到充分发挥，因为在那里经常会应用到激光通信技术，它在外层空间进行，所以不会受到大气层的影响。还可以利用“星际激光链路”技术来缩短全球卫星通信中的“双跳”法的信号时长。有专家提出“在卫星激光通信在比微波通信数据速率高一个数量级的理想情况下，天线孔径尺寸会比微波通信卫星减小一个数量级”的观点。那么如果在空间无线电通信中以激光作为载体来进行工作和运行未来的卫星之间进行激光通信是很有前途的。 Satellite communication data rate in the future will be achieved through laser communication, laser advantage will be given full play in Internet satellite networks, because there are often applied to laser communication technology, it is in the outer space, so I dont get the atmosphere influence. Can also use the star laser link technology to reduce global satellite communications in the double jump method of signal duration. The expert puts forward in satellite lase