The Reseach And Simulation Of The Techniques Of Papr Reduction Of Signal In LTE-A Uplink And Downlink

Since the20thcentury, the mobile communication has become the fastest growingand the most valuable one during the industries in the world. It has great influence onmedical treatment, sanitation, military, broadcasting and so on. In order to satisfy therequirements of the transmission rate，The Third Generation Partnership Project draftsthe Long Term Evolution-Advanced (LTE-A) standard. In the standard, the peak rate ofuplink need to reach500Mbps and the peak rate of downlink reach1000Mbps.Orthogonal Frequency Division Multiplexing (OFDM) technology which has highspectrum efficiency and good resisting frequency-selective fading perfermance is theone of the key technologies of LTE-A. However, the OFDM technology will bring inhigh Peak-to-Average Power Ratio (PAPR), which not only undermines theradiofrequency circuit, but also emerges distortion. The Conventional PAPR reductiontechnologies will cause some ploblems, such as performance decline, disturbingReference Signal (RS). Therefore, it needs to design the signal with low PAPR andensuring the spectral efficiency and Signal-to-noise ratio (SNR) of RS.The work of this thesis is about the PAPR reduction of transmit signal and RS, andthis thesis is arranged as follows:Chapter1introduces the frame structures of LTE-A uplink and downlink. As thekey technology, OFDM will bring high PAPR and out-of-band radiation. In this chapter,the Complementary Cumulative Distribution Function (CCDF) of PAPR and spectrumare anslysised via statistics theory.Chapter2investigates the PAPR reduction of LTE-A downlink system. Threepredistortion methods are introduced firstly, and then compared the simulation results ofPAPR and Bit Error Rate (BER). Design three windows which not only reduce thePAPR, but also do not influence the RS. Give a theoretical analysis of the noise of peakcancellation. distribution in frequency domain. At the receiver, the noise of peakcancellation takes part in the decoding process as a part of channel noise. Chapter3studies the PAPR reduction of LTE-A uplink. Two different methods ofpeak cancellation are listed. The new one has a little superiority in PAPR. The next partgives generation of RS. According to the characteristics of reference signal, the methodsof PAPR reduction of reference signal ar e introduced and compared.Chapter4gives five methods to ruduce the out-of-band radiation.The simulationresults show that the N-continous and spectrum pooling are the best methods. Besides,the out-of-band suppression and PAPR reduction are combined into two constructions.The one which sets the PAPR reduction before has a better performance of PAPR andout-of-band suppression.Chapter5summarizes the work of this thesis and discusses the future research onPAPR reduction and out-of-band suppression.