CSFB Voice Solution Of TD-LTE System

LTE networks have been developing rapidly around the globe, the voice solution, which is based on such network is also publicly acknowledged as a significant issue in the industry. Differing from 2G/3G network, which supports voice calls over CSD, LTE network relies heavily on a unified PSD architecture. However, in order to achieve this goal over the entire cellular network, we need to develop an IMS deploying over the whole network---a task as such is fairly difficult to achieve at an early stage of the network development. This paper puts emphases on the CSFB voice solution, which is widely approved in the communication industry. The technical approach is as follows:when idle, the LTE terminal resides in the LTE network; as soon as the calling/called process begins, LTE terminal moves back to 2G/3G network, and we process such activity as a normal Circuit Switched practice. CSFB requires relatively lesser NE to be reformed, and secure the early investment on the 2G/3G networks, which are advantages that can rarely be duplicated by other solutions.This paper starts with TD-LTE network, developed by CMCC, firstly comparing different voice solutions based on the LTE network, than elaborating on the detailed procedures of CSFB network module, mobility management and signaling process. Through the understanding of these processes, and each significant link in the CSFB, we have proposed four analyzing methodologies. At last, for the purpose of significantly improving the general quality and experiences of the customers, as well as laying the foundation for future practice, we shall look further into the actual case results, in order to offer the management specific and targeted suggestions.