Implementation Of PHY/MAC Joint Simulation For LTE And Research Of Scheduling Algorithm

With the continuous development of wireless communication technology, the research of communication protocol comes into a new phase. Therefore, using the method of simulation to evaluate the performance of links and systems, as well as carry out research of related algorithms, put forward higher requirements. Compared to the traditional link-level and system-level simulation, PHY/MAC joint simulation is a better method on the study of wireless communication system. By introducing real physical layer in system-level simulation, and adding MAC layer’s control in link-level simulation, joint simulation makes the simulation more accurate and reliable.OpenAirInterface(OAI) is an open-source simulation platform for wireless communication and signal processing, which has set up a good system framework. In this paper, a PHY/MAC joint simulation has been achieved based on the research of OAI simulation platform. Implementation work includes the design and implementation of physical layer process, development of MAC layer’s random access, scheduling, multiplexing and demultiplexing function module, and the defining and implementation of PHY/MAC interfaces. Moreover, in order to improve the efficiency of joint simulation, as well as meet different needs of research, the technology of PHY abstraction has been applied and the multi-machine working mode has been implemented. The simulation and validation results illustrate that, the PHY/MAC joint simulation has simulated the real LTE system, multi-machine working mode has been successfully implemented between different computers, each function module of MAC layer is running correctly, and PHY abstraction has reduced the simulation time on the basis of accuracy.Scheduling is a key mechanism for LTE traffic control, assigning users the time and space resources. The research of scheduling algorithm is not only the theoretical extension of the Implementation of joint simulation, but also reflects the advantages of joint simulation. An effective scheduling algorithm needs to compromise between fairness and efficiency. In this paper, on the basis of research on traditional scheduling algorithm, by introducing the concept of utility economics and applying ideology of marginal utility, an innovative scheduling algorithm based on utility function is proposed, which achieves the unity of fairness and efficiency. Simulation results show that the scheduling algorithm has maximized the throughput of the system on the basis of ensuring high level fairness between different users.