Research On The Interoperation Between Gsm And Td-scdma System

With the rapid development of mobile communication systems, people hope to obtain multimedia services such as packet data, video and picture phone etc. besides voice service. All these requirements hastened the birth of the third generation mobile communication systems. TD-SCDMA, as a 3G standards suggested by China, is set by the Ministry of Information Industry of China as the telecommunications industry standard of 3G, which carry a big dream for Chinese from a country owing large number of telecommunications consumer to a country with advanced telecommunication technologies. How can we make full use of existing GSM/GPRS network and equipments, optimize the allocation of resources, provide users with rich, reliable 3G services, and realize a smooth, seamless evolution to the 3G. In addition to choosing the appropriate network evolution process, optimizing network structures, a higer requirement should be implemented for services working process of different network structure in order to realize smooth transition of the business. In this paper, interoperability issues of TD-SCDMA and GSM systems are discussed, signaling processes in the interoperability are researched and analyzed under the condition of keeping the signaling quality.Firstly, the handoff technique of present GSM system and TD-SCDMA system is researched. secondly,the problem of interoperability between the two systems which will be met in the operation of TD-SCDMA is discussed on the basis of the maximum utilization of available resources. The correlated basic concepts, the principle and scheme of interoperation is presented. The interoperation between TD-SCDMA and GSM system is focused on, which include cell selection, cell reselection and cutoff. The related signaling is analyzed in detail. TD-SCDMA network mainly aims at satisfying the requirements of high-speed mobile data business users, supporting reverse the re-selection and switch from GSM to TD-SCDMA system. The voice and medium and low rate data services is provided by the GSM network. The re-selection and switch from TD-SCDMA to GSM system is supported. The two networks work well in different function, are complementary. This is an ideal operation mode.