TD-LTE Base Station Location Optimization Study Based On Hybrid Immune Algorithm

With the rapid development of the communication industry, mobile communication technology has entered the 4G era. On December 4,2013, TD-LTE licenses have been issued to three major telecom carriers by the Ministry of Industry and Information Technology (MIIT). Whether the base station location is reasonable has a great impact on the communication quality of TD-LTE network and its construction costs. But for now, the challenging issues of location selection, construction and retainment for mobile communication base station are going prominent, and have become major constraints for construction and development of 4G in China. Therefore, the optimization of base station location has become an important topic in the research field of TD-LTE network construction.The optimization of TD-LTE network base station location is a NP-hard problem, which is of high complexity. Normally it can be solved by various artificial intelligence algorithms. Immune algorithm is the latest research achievement in the field of intelligent computing, and it is widely used in the field of engineering application and scientific research because of its simple model, fast convergence rate and easy implementation, etc. However, because of the complexity of NP-hard problems, traditional Immune Algorithm for solving NP-hard problems has shown some inherent disadvantages, such as relatively low convergence accuracy, slow convergence rate in later evolutionary process, and the emergence of local optimal when solving problems of high complexity. Therefore, it is necessary to study improved immune algorithm, which is of important theoretical significance and practical value for solving complex optimization problems.Hybrid algorithm can overcome the shortcomings of single algorithm. In order to improve the efficiency of Artificial Immune Algorithm in optimizing the problems of TD-LTE network base station location, this paper proposes a hybrid immune algorithm based on the thought of hierarchy and co-evolution, namely Layered Co-evolution Immune Algorithm (LCIA). The proposed algorithm divides the population into two layers, makes immune operation on the lower and makes co-evolutionary operation on the upper. Simulation results on standard test functions show that LCIA can improve the diversity of the population and the searching efficiency at the same time.According to the features of TD-LTE network, the principle and objective of base station location, this paper establishes a mathematic model of TD-LTE network base station location, and presents the framework and process of LCIA algorithm. At last, the paper conducts emulation experiments and compares with algorithms proposed by other papers. Experimental results show that LCIA algorithm can obtain higher coverage rate and higher network capacity with lower cost. It provides a new idea for telecom carriers in solving the problems of base station location.