SDH Transmission Network Constructing Design

We know that in today's society is information society. Highly developed information society can provide a variety of communication network , A variety of telecommunication services. Transmission through the communication network, exchange, deal with the amount of information will continue to increase. This requires the modernization of communication networks to digital, integrated and intelligent direction and personal development.Transmission system network are important components of.A direct transmission system restricts communication network hair Exhibition. At present the world to develop the information superhighway. One key point is the formation of large-capacity optical network transmission. Continuously improve the signal transmission line on rates, widening the transmission band. Transmission network at the same time the user wants to have world-wide interface standards. Able to achieve our global village every user can easily anytime, anywhere communications.SDH (Synchronous Digital Hierarchy) is an multiplexer, line transmission and switching capabilities into one, unified network management system operated by the General information transmission network. Advisory Committee on International Telephone and Telegraph (CCITT) (now ITU-T) in 1988 to accept the concept of the SONET and SDH renamed. Applies not only to make it also applicable to fiber-optic microwave and satellite transmission system of the Common Technical. It may realize the network effective management, the real-time service monitoring, the dynamic network maintenance, intercommunication between the different manufacturer equipment's and so on many functions. It can raise the network resource use factor, reduce the management and the maintenance cost greatly, realizes nimble reliable and the highly effective network movement and the maintenance. Therefore is now the world information field in the transmission technology aspect development and the application hot spot. Receives the people widely to take seriously.SDH is not only a network principle, is also a set of multiplying method. Down to the SDH foundation, may complete one nimbly reliable to be able to carry on the remote control management the national telecommunication transmission network the world telecommunication transmission network. This transmission network may expand the new service very conveniently, but may also cause the different factory production the equipment to carry on the intercommunication use. SDH mainly has the terminal multiplexer in the transmission basic network unit (TM), the regenerator (REC), to divide inserts the multiplexer (ADM) and the synchronization digital cross-connect equipment (SDXC) and so on, Although its function varies, but actually has the unification standard light connection, can realize in the network fiber optics section crosswise compatible, namely equipment intercommunication. At present, the band width demand and the technology had demonstrated that has the necessity to take into the SDH technology huge superiority the access network domain, causes SDH the function and the connection approaches the user as far as possible. Applies SDH in the access network the main superiority to be as follows: 1) regarding requests high reliable, the high grade service large-scale business user, SDH to be possible to provide the ideal network performance and the service reliability. This time may use the SDH system directly is connected by point-to-point or the ring topology form and the user; 2) may increase the transmission band width, improvement network management ability, the simplification maintenance work, reduces the running attention cost; 3) the SDH inherent flexibility enables the network operation to be possible to provide the user to need long-term and the short-term service as well as the network need effectively quickly. Regarding the development extremely rapid honeycomb communications system, uses the SDH system to be especially suitable, may provide the 2Mb/S transparent channel which nimbly rapidly needs.The present paper mainly introduced the paper research background, the SDH transmission principle and the characteristic, the SDH application and the trend of development in the first chapter of introduction; The second chapter has carried on the analysis to the SDH technology, mainly introduced the SDH signal frame structure, the SDH network architecture and the network protection mechanism, the light interface type and the parameter, fixed time with synchronized, the transmission performance analysis; The third chapter introduced some prefecture SDH transmission network construction plan in detail; The fourth rules carry on the target test to the SDH transmission system; Has carried on the summary in the last chapter of conclusion to the paper work, and proposed next step studies tentative plan. And first, second chapter elaborate for the principle, third, fourth chapter are present paper research work's main manifestations.