Research And Design Of Signaling Processing Module In LTE Femto Gateway

Femto home base station System, is a nano cellular base station system, which is using IPbroadband technology, borrowing fixed broadband access as their backhaul networks. Femtobase station remote from dedicated and supporting Femto HeNB GW, realizing theinteroperable comunication from the IP network to the mobile core network, in order toprovide users with a small region-wide cellular network access services. Meanwhile a newgeneration of wireless communication technology TD-LTE has been in the experimental stage,and will be put into operation in near future. In the course of future network deployment,Femto system with the support of TD-LTE technology is undoubtedly an important solutionwhich resolve the conflict between weakness of indoor signal coverage and interior explosivegrowth of digital audio business.After deep study of LTE system architecture, basing on the analysis of TD-LTE FemtoGateway’s technical specifications and standards3GPP protocol, this paper determine theplace of gateway system we are working on in the network. HeNB GW only handle signalingconvergence and forwarding in the control plane, and HeNB is directly connected with theS-GW via S1-U interface in the data plane. Then, the the design and working principle of HAmodule, system management module, signaling processing module, security access modulewithin the system are functionally analyzed. Based on the analysis of the required flow for S1protocol stack, the functional requirements, working principle and design programs ofsignaling processing module is given in a detailed way. Finally, a software implementation fora signaling processing module with effective convergence and forwarding is presented in theATCA hardware architecture.In this paper, the gateway system signaling processing module is achieved throughfunctional modular design, consist of the context management components, performancestatistics components, signaling control components and layer management components.Layer management component is primarily responsible for interactive communication ofsignaling processing module and the peripheral modules and controlling overall signalingflow in the signaling processing module. Signaling control module,according to the type of signaling, carry out calibration, forwarding, responding and other operations, so that thesignaling process meet the requirements of S1AP protocol. Three context managementcomponent provides a flexible and efficient basic operation of the UE context, the HeNBcontext, MME context, supporting the signaling control components to make a correcthandling for the received signaling. Performance statistics component is mainly used forchecking error and making statistics of running status information in the system. Finally testshows that the signaling processing module can process signaling of the required flow in theexpected way. various functional modules developed in gateway are running well with eachother, reaching the pre-development purposes, obtaining staggered results.