Research On Interference And Coexistence Of TD-LTE System With Different System

Currently, domestic carriers are large-scale construction TD-LTE cellular mobile communications network. The scarcity of radio spectrum resources are increasingly prominent, the future is likely to occur TD-LTE systems and different systems using the same or adjacent frequency bands within the same geographical area network deployment scenarios. Due to the non-ideal nature of the wireless communication system transceiver device, it may cause interference between each other coexist in the same area of the wireless communication system, thus affecting the performance of the wireless communication system. Therefore, we should take what the appropriate degree of protection and avoidance measures to improve the 700MHz band TD-LTE-CR and digital broadcast television system performance, as well as power control parameters and reasonable value, improve the distribution of power, can make TD -LTE MiFi users can power the same as ordinary UE good coexistence with other systems, but has little impact on system performance, the above two points are of great significance for theoretical research and engineering practice.Firstly, using a combination of deterministic analysis and system-level Monte Carlo simulations of static method, the 700MHz band TD-LTE and digital broadcast television system (DTMB) interference coexistence studied. Through a detailed analysis of the designed four kinds of coexistence scenarios drawn up between the urban and rural environment systems coexist required isolation conditions and provide reference for reasonable spectrum planning and network deployment.Then consider adding TD-LTE base stations CR (Cognitive Radio) case module, access to the wireless environment under which the spectrum occupancy information spectrum detection method, using a spectrum detection method by detecting air signal CR technology, changing the traditional fixed frequency allocation dynamic frequency allocation. By detecting the spectrum occupancy information DTMB system, to control the working state of TD-LTE base station. At this point the simulation scenario has changed, still a combination of deterministic analysis and system-level static simulation Monte Carlo method in the detection accuracy of certain CR, CR detection method, under the protection of distance, isolation and bandwidth constraints, calculated required to provide additional adjacent channel interference power ratio (ACIR). Draw conclusions avoidance measures interference analysis and suppression of interference between the two systems.Finally, we study the problem of interference coexistence between TD-LTE and LTE FDD power MiFi user system and WCDMA system, still uses a static system-level Monte Carlo simulation method, simulation results show that:The power control parameters to take reasonable value and improve the allocation of power, you can make in a simulation scenario examined in TD-LTE MiFi users can power the same as ordinary UE good coexistence with other systems, but has little impact on system performance.