Design Of TD-LTE Indoor Distribution System And Research On Optimization Algorithms

In recent years, mobile communication systems have developed rapidly and the number of mobile users is increasing. With more and more high buildings, traffic density and coverage requirements are continuing to rise. With the rapid expansion of the number of users, we need to provide better indoor mobile communications business. But the high buildings will cause shielding effect and blind area. The phone signal is weak in the lower layer of large buildings because the communication device is not working, so it will form a blind.In the middle floors of large buildings the phone will receive different base station signal, so the signal will overlap or produce the ping-pong effect or occur frequent switching. This will reduce the user’s perception of the signal. This is due to the limitations of antenna height, it will form a blind in the middle floors of large buildings. In addition, in some buildings such as shopping centers, shopping malls, airports, convention centers, the stadium. Although cell phones can normal call. But in these places the user density is too large. Mobile phone is very difficult to dial the phone, because the channel of base station often happens congestion.Indoor distribution coverage is for mobile phone users inside the buildings. And indoor distribution system is to ensure coverage, capacity, signal quality and enhance mobile signal in the buildings. Indoor coverage system is a better solution to the above-described problem in the mobile communication system.we use indoor antenna distribution system to distribute the signal in every corner of the room, to ensure that the area within the building has good coverage. The principle of TD-LTE indoor distribution system is to use indoor distributed antenna system to achieve coverage of the signal in the buildings that outdoor communication signal can not penetrate inside. Since there is no mathematical model and algorithm at home and abroad to solve the problems of the present MIMO dual channel mode in the reform and the expansion scheme of the existing TD-LTE indoor coverage distribution system, which are huge engineering quantity, hard coordination and big project investment.This paper has established the passive indoor distribution system model based on MIMO dual channel mode. And an algorithm based on population decomposition strategy has been designed to solve the problems. At the same time this paper studies the optimization algorithm, and a fast convergence of the hybrid genetic algorithm is proposed. Using complicated one dimensional function and two-dimensional multimodal Shaffer function in complex global optimization problems as examples, shows that performance of this hybrid genetic algorithm is better than single conjugate gradient method and genetic algorithm and have achieved good results.