Design And Research Of 5G Carrier Technology GFDM System Based On NI USRP

In recent years,in the fields of high frequency,large bandwidth,and low latency under the application background of 5G technology,the limitations of the original 4G communication system LTE have become more and more obvious,which has gradually failed to meet the requirements of the development of the times.Although the OFDM carrier modulation technology used in the existing LTE uses multi-carrier technology to improve the utilization of bandwidth,the OFDM carrier waveform often causes the problems of large out-of-band radiation(OOB)and high peak-to-average ratio(PARP).This largely limits the frequency bandwidth and interference problems caused by multiuser applications.Nowadays,5G NR systems have gradually adopted GFDM as the carrier waveform of the communication system to solve the problems of out-of-band radiation and excessive peak-to-average power ratio in OFDM technology,which leads to a reduction in the utilization of spectrum resources and easily causes interference for other users.In order to optimize the above-mentioned problems,this thesis uses GFDM carrier technology as the research object to build a GFDM communication system,and further improves the OOB parameters and PAPR parameters of the communication system through the FW＿CCDF method.The system platform built this time is not limited to basic theoretical simulation,and the communication system platform built is a verification platform at the same time.The main research content and work of this thesis are as follows.First,the mathematical model,implementation principle,research background of GFDM carrier modulation and the key technologies used will be introduced.Then,the Labview software development platform and USRP equipment are used to design the main functional modules of the GFDM carrier communication platform,including the design of adding and removing cyclic prefix,channel equalization,signal synchronization,GFDM modulation and demodulation,etc.The method improving the FW-CCDF is introduced and the results obtained after the system is applied are verified,and a carrier communication waveform with better performance is obtained.The out-of-band radiation of the newly constructed GFDM carrier communication platform reaches-50 dB,which is about 30 dB lower than that of the OFDM carrier system,and the average peak-toaverage power ratio is 7dB,which is about 5dB lower than that of the OFDM carrier system.Finally,the collection and transmission of random numbers,texts,and random pictures is realized based on the QAM modulation method in the GFDM carrier communication system,and the final results are tested and verified in a laboratory environment.In addition to displaying the final text and the transmission results of random pictures,it can also display the GFDM carrier waveform and the system’s constellation diagram and frequency domain diagram in real time.The system platform can intuitively and conveniently obtain the system parameter data.It provides a platform for better follow-up improvement of GFDM carrier communication technology.