Research On Interference Coexistence Between Communication Systems In IOT Smart Home Scenario

The study on smart home has already more than10years of history, but subject to the constraints of the communication technology, the pace of development has been slow. With the rapid development of Internet of Things (IOT), smart home which regarded as one of the main application domains, has obtained more and more people’s attention. Smart home system is gradually developing towards network, information and intelligence, and the development idea and application prospect become clearer. But overall, the smart home study is still in the exploratory stage and many solutions remain to be validated. The research progress of home network technology plays an important role in promoting the development of smart home.The paper focuses on the scenarios of IOT smart home, analyzes smart home system networking technologies and the principles of inter-system interference. It needs to be mentioned that the key points of the thesis are the interference coexistence of2.4GHz LTE and Wi-Fi systems indoors and the research of system-level simulation. First of all, the article uses deterministic analysis method to find the additional isolation which can protect LTE system from inter-system interference, and also provide theoretical reference for system-level simulation.Secondly, according to modeling the key algorithm of LTE and Wi-Fi systems, determining the network topology, antenna model, simulation parameters, and developing the system-level platform to assess the uplink and downlink performance of LTE system when Wi-Fi devices are existed in different deployment density conditions.The simulation results show that, the interference from Wi-Fi system in the uplink of TD-LTE is lighter, and the interference in the downlink is more serious. There is a greater loss of system capacity, and wider isolations are needed to meet the demand of the coexistence. In addition, the platform simulates different coexistence performances in different transmit powers of Wi-Fi system, and the result shows that the coexistence performance can be effectively improved when the transmit power is decreased on the premise that the coverage scopes of Wi-Fi system are guaranteed.