A fast handover method of a td-lte communication system based on target cell pre-carrying

Abstract

Aiming at the requirements of frequent cell handover, short handover time and high handover success rate in high-speed railway TD-LTE communication system, a fast handover method of TD-LTE communication system based on target cell pre-carrying is proposed. According to the train's running position, speed and direction, after the network planning is completed, a list of neighboring cells is generated in advance, and the switching position of each switching zone is preset, that is, the longitude and latitude position information. Before the train enters the overlapping area of ​​switching between two cells , when the distance from entering the handover zone is a certain value L, the source base station eNodeB determines and sends the pre-bearer information to the target base station eNodeB according to the measurement report of the user terminal UE, and the target base station eNodeB performs the evolution packet system ( Evolved Packet System (EPS) resources to bear the load, when the train enters the handover zone, if the train meets the handover criteria, the train will be handed over from the source cell to the target cell. Therefore, this method reduces the handover delay and is beneficial to improve the handover success rate. The method can dynamically adjust the switching method according to the mobile speed of the UE, solve the problem of fast switching in a high-speed mobile environment, reduce the number of communication drops, improve the success rate of switching, enhance the service quality of high-speed broadband mobile services, and promote high-speed railway trains. The development of domestic multimedia broadband mobile Internet services meets the growing needs of passengers for mobile communication services.

Description

Technical field: [0001] The present invention aims at the high-speed railway Time-Division Duplex Long Term Evolution technology (Time-Division Duplex Long Term Evolution, TDD-LTE or TD-LTE) communication system with frequent cell handover, short handover time, and high handover success rate requirements, and proposes a method based on A fast switching method of a TD-LTE communication system pre-carried by a target cell. The method can be applied to a fast handover method of a TD-LTE, Frequency-Division Duplex Long Term Evolution (FDD-LTE or FD-LTE) communication system in a high-speed rail environment. Background technique: [0002] Generally, the handover process in the LTE system is divided into the following three steps: [0003] 1. Switch measurement (including measurement filtering, algorithm trigger measurement report); [0004] 2. Switch decision (switching algorithm); [0005] 3. Switch execution; [0006] The handover measurement is completed by the user equipm...

AI Technical Summary

Problems solved by technology

When the user terminal UE moves fast enough that the time for crossing the handover area is less than the minimum delay for the system to process the handover, the handover process cannot be completed, resulting in call drop

[0011] Due to the particularity of the high-speed railway channel environment and networking mode, the above-mentioned A3 handover judgment criterion cannot adapt to the high-speed railway environment. Due to the high-speed running of the train, the handover time is short; in addition, factors such as complex terrain and surrounding electrical equipment on the high-speed railway The channel environment will also have a great impact. Using the A3 handover judgment criterion will cause frequent handover failures, lower handover success rate, lower communication quality, and poor customer experience. Therefore, it is necessary to consider adopting a judgment criterion that adapts to the high-speed railway environment

Images