Research And Implementation Of 5G Dual-Band Transceiver

With the continuous development of science and technology,people's requirements for communication quality continue to increase,and mobile communication technology is also constantly innovating.From the first-generation mobile communication system in the 1980 s to the fifthgeneration mobile communication system 5G,which is about to be used on a large scale,all efforts have been made to solve problems such as the diversity of communication methods,communication rates,and communication capacity.Today,mobile communication equipment often needs to meet the requirements of multi-mode work,so in the 5G era,the research on 5G dual-band transceivers is particularly important.At present,the current mainstream dual-band transceiver architecture has two independent links,which are obviously easy to be highly integrated.Therefore,in order to reduce the system size,it is necessary to use a broadband or hybrid architecture to design a 5G dual-band transceiver.This thesis mainly focuses on the research and design of the 5G dual-band transceivers with the center frequency of 3.5GHz and 4.9GHz.By analyzing the advantages and disadvantages of the basic architectures of the single-band transceiver and the current popular dual-band transceiver,a broadband architecture with low-IF architecture is adopted to design the 5G dual-band transceiver,in which some devices are shared.The 5G dual-band transceiver has a channel bandwidth of 100 MHz in both bands and a TDD operating mode.The test results show that 5G dual-band transceiver has good performance and meets the system requirements.In the receiver part,the in-band gain flatness is less than 1.5d B,the noise figure is less than 5.5d B,the image rejection ratio is more than 40 d Bc,the transceiver switching time is about 700 ns,and the dynamic range is between-80 d Bm and 0d Bm.The EVMs at 3.5GHz of 16 QAM,64QAM and 256 QAM modulated signals with a symbol rate of 50Msym/s are 2.049%,1.865%,and 1.728%,respectively.The EVMs at 4.9GHz band is 1.301%,1.158%,and 1.083%,respectively.In the transmitter part,the maximum output power in both bands is greater than 17 d Bm,the in-band gain flatness are less than 1 d B,the image rejection is greater than 40 d Bc,the ACPR at the maximum output power is less than-45 d Bc,and the out-of-band spurious rejection is greater than 45 d Bc.The EVMs at 3.5GHz of 16 QAM and 64 QAM modulated signals are 1.854% and 1.692%,respectively.The EVMs at 4.9GHz are 1.557% and 1.421%,respectively.Based on the 5G dual-band transceiver,the receiver part has been improved to a new 5G dualband synchronous receiver with a hybrid synchronous architecture,in which two-band signals can be processed simultaneously.The test results show that the new 5G dual-band synchronous receiver has good performance and meets the system requirements.In each band,the signal bandwidth is 80 MHz,the gain flatness is less than 1.5d B,the noise figure is less than 5.5d B,the image rejection is greater than 40 d Bc,and the dynamic range is between-70 d Bm and 10 d Bm.The EVMs at 3.5GHz of 16 QAM,64QAM and 256 QAM modulated signals with a symbol rate of 50 Msym/s are 1.481%,1.313%,and1.238%,respectively.The EVMs at 4.9GHz band are 1.962%,1.763%,and 1.634%,respectively.