Research On Transmitter Radio Frequency Conformance Testing And Papr Reduction For Carrier Aggregated Terminal

In order to reach peak transmission rate of1Gbps in downlink and500Mbps in uplink of IMT-Advanced system, the LTE-advanced system needs to support a maximum bandwidth of100MHz. Using current spectrum allocation schemes, it is hard to find a complete frequency band capable of carrying the LTE-Advanced system. Thus,3GPP proposed the solution of multi-carrier aggregation (CA) technology to meet the spectrum resource demand.In this paper, the design principles, aggregation type and terminal transmitter structure of carrier aggregation technology are investigated deeply. With the introduction of carrier aggregation technology, higher requirements for the design and characteristics of the RF terminal are needed and it broke the low PAPR characteristics of uplink. Therefore, researches on the following two questions are conducted.On one hand, transmitter Radio Frequency (RF) conformance testing of carrier aggregation terminal are performed. Before we build the simulation platform in ADS, the test purpose and minimum requirement of transmitter intermodulation are thoroughly analysed and the simulation approach is figured out. Then, the intermodulation senarios of different carrier aggregation bandwidth are simulated and the factors that affect the transmitter intermodulation are analysed and concluded. As the RB number allocated to one user and the RB spacing increase, the intermodulation interference strengthens, which root from the increase of the Peak Average Power Ratio (PAPR) associated with the carrier aggregationOn the other hand, PAPR reduction technologies are researched. The PAPR characteristcs of CA uplink are analysed and two improved Selective Mapping (SLM) schems for PAPR reduction are put forward which eliminate the signaling overhead and reduce the computational complexity of SLM. The position of phase process for one scheme is after DFT, the other of which is before DFT. The two schemes are simulated and verified in MATLAB and their PAPR reduction performance are also compared to each other.