Study And Simulation Of Multi-antenna Constant Envelope Orthogonal Frequency Division Multiplexing Transmission Techniques

Multiple input multiple output-orthogonal frequency division multiplexing(MIMOOFDM),which is one of the key techniques in the fifth-generation(5G)mobile communication network,is capable of achieving high data rate transmission over multipath fading channel.However,MIMO-OFDM suffers a high peak-to-average power ratio(PAPR)waveform,which limits the working efficiency of a high-power amplifier(HPA).To overcome the high PAPR,constant envelop OFDM(CE-OFDM)scheme applies phase modulation into the conventional OFDM procedure,significantly enhancing the efficiency of HPA thanks to its near OdB PAPR waveform design.The thesis studies the transceiver design and parameter selection of multiple antenna CE-OFDM system,i.e.,MIMO-CE-OFDM,and investigates the performance of MIMOCE-OFDM under various channel settings through numeric simulation and theoretical analysis.The main contribution and conclusion of this thesis are as follows.First,the thesis presents the system model of MIMO-CE-OFDM,and analyzes its performance with the interaction between modulation,parameter selection,channel condition,and signal reception.It shows that MIMO-CE-OFDM is capable of achieving frequency domain diversity gain beside of space diversity from the phase modulation process.By comparing with the MIMO-OFDM system,MIMO-CE-OFDM provides a better bit error rate(BER)performance,especially for a channel with rich multipath components.Secondly,the thesis studies the MIMO-CE-OFDM precoding system,and compares the effects of digital precoding and beamforming technology in terms of signal fluctuation and BER performance.The results show that digital precoding can achieve BER performance gain,however at the cost of PAPR regrowth,while the beamforming scheme can achieve BER improvement with a OdB PAPR waveform.Finally,the thesis explores the application prospect of index modulation technology in the MIMO-CE-OFDM system.The thesis discusses the BER performance of antenna index modulation and subcarrier index modulation in the MIMO-CE-OFDM system respectively.The results show that compared with the traditional index modulation MIMO-OFDM performance,the index modulation MIMO-CE-OFDM signal still has the signal waveform characteristics of lower PAPR,and can achieve a better compromise between spectral efficiency and BER performance.In addition,compared with the performance of the MIMO-CE-OFDM system,the subcarrier index modulation MIMOCE-OFDM system using the interleaving technique can achieve a certain BER performance advantage.