Ue Radio Frequency Conformance Testing And Researching For Carrier Aggregation In TD-ITE-A System

The Long Term Evolution (LTE) Project of Universal Mobile Tele-communications System (UMTS) is during the process of researching and industrialization. As an important part of the process, TD-LTE system which uses the technology of Time Division Duplex (TDD) also received much concern.This paper focused on the Radio Frequency (RF) characteristics of User Equipment (UE) transmitter for Carrier Aggregation (CA) in TD-LTE-A system and conducted thorough research on them. Firstly, the CA technique and the nonlinear characteristics of RF system were briefly introduced, meanwhile, the RF requirements of UE in CA scenarios were summarized. In addition, a simulating platform was established according to the RF requirements of UE transmitter and test cases such as Spectrum emission mask (SEM), Adjacent Channel Leakage Ratio (ACLR) and In-band emissions were simulated and analyzed. During the process of simulation, the nonlinearity of RF Power Amplifier (PA) was specially analyzed in this paper since it had great influence on the characteristics of Uplink transmitting signal. Lastly, facing to the fact that CA technique drove the Peak to Average Power Ratio (PAPR) of Uplink transmitting signal to the extreme level, this paper studied a common linearization technique called Maximum Power Reduction (MPR) of UE. Furthermore, this paper discovered that both the RF factors of UE and the characteris-tics of signal itself that had great impact on the value of MPR.The simulation results and research conclusions in this paper can not only guide the RF design of UE in TD-LTE-A system, but also provide valuable references to the modification of standards of UE RF conform-ance testing.