Research On The Interference From Radar To TD-LTE System In The 2300～2400 MHz Frequency Bands In China

LTE will be widely used as a communication standard in global, and the world’s major countries have started to deploy LTE commercial network. For China, LTE will also be focused by telecommunications industry. The three operators will take LTE system as the evolution of the future direction of its communications system, so focus on LTE technology has become one of the objects. However, the allocation of resources has become a major problem restricting the development of LTE. Currently, China’s TD-LTE test is mainly in the 2.3GHz band. If the frequency range is not in accordance with the future frequency scheme, it will have a seriously negatively impact on industrial development. Therefore, the Study on LTE systems and related systems in the 2.3GHz band coexistence issues become very important and urgent.Radar is used to detect and locate reflective objects such as aircraft, ships, spacecraft, vehicles, pedestrians and the natural environment of a magnetic system. It works by detecting the energy radiated into space and reflected by the object or goal signal back. The frequency bands of radars are different in different countries and regions. In October 2002, the Ministry of Information industry of china announced a Frequency Allocation Scheme. This scheme allocated 2300-2400MHz to TD-SCDMA system as a candidate band, which the radar has been used to locate in. As the evolution of TD-SCDMA system, LTE can be expected in the near future that it will be deployed in this band. Therefore, it is important to analyze the interference from radar to TD-LTE system.In this paper, first we propose a new deterministic calculation method to calculate the interference from radar to LTE in the 2300-2400MHz bands, based on the 3 GPP LTE standard and the International Telecommunication Union ITU standard. Then, by the link-level simulation method, we simulated LTE BER. And According to the simulation results this paper calculates the necessary isolation between typical radars and TD-LTE system. Deterministic calculations and link level simulation results show that large isolation is needed between the two systems. So some measures for interference mitigation must be taken such as distance separation, frequency separation and so on.