The Implementation Of Radio Interface Layer In Mobile Terminal

In recent years, the rapid development of the wireless communication network has brought enormous change for the intelligent operating systems of mobile phone. As a member of the top five intelligent operating systems, the Windows Mobile system evolves into Windows Phone7. It abandons former business concept, but strengthens the user experience on entertainment, social intercourse and other aspects. In the next few years Windows Phone7will have rapid development and perhaps will replace the dominant status of Symbian system.Radio interface layer is the core component, which is the base for realizing all applications related to wireless connection, to support wireless communication function in Windows Mobile system. It is precisely because of the accession of RIL that Windows Mobile system has the functions of mobile phone. The more the RIL driver realizes its functions, the more rich upper application will be. This accords with the requirement of the development of intelligent mobile phone. But Microsoft doesn’t disclose the design documents of RIL, and OEM manufacturers set it as confidentiality, so there are few reference on the development of RIL driver. In this context, this paper focused on the research and the implementation of radio interface layer on mobile terminal, supporting the application to call into RIL to obtain IP address, which provides a reference to realize RIL drivers related to other applications. It first gives a detailed analysis and a summary of RIL architecture as well as the work flow in the Windows Mobile/Phone system, and introduces the RIL remote communication mechanism in a dual-core system. Secondly, it realizes a typical API function RIL_GetGPRSAddress of the RIL layer in the dual-core system, and takes it as the template to detailedly describe the implementation process of the RIL driver. Finally, an upper APP is developed to call into this API, then the RIL driver is rigorously tested with the executable file generated from the APP. The result shows the RIL driver developed in this paper, can transfer the IP address, which is allocated to terminal by network, to the upper layer according to upper requirement, which validates that the APP correctly calls into the RIL layer, and verifies the accuracy and reliability of the implementation of RIL driver, and also reaches our designing requirement.