Research On Rf Front-end Of 5G Millimeter-wave In 39GHz Band

With the continuous development of mobile communication technology,the sub-6GHz frequency band of 5G communication system has been commercialized.In order to further meet the increasing demand of data services,researchers focus on millimeter wave frequency band.As a candidate frequency band for 5G communication systems,millimeter wave has abundant spectrum resources.In July 2017,China has set 26GHz and 39GHz as experimental bands for 5G millimeter wave.In this paper,the millimeter-wave RF front end in the 39GHz band of 5G communication system is studied.Considering the structure of the transceiver and the specific index requirements of the RF front end,the paper mainly designs the local oscillator module and the transceiver channel module of the millimeter-wave RF front-end.The transceiver front end in this paper adopts the superheterodyne structure scheme,and the local oscillator module adopts the phase-locked loop frequency synthesis scheme.Firstly,LO module with a frequency output range of 29.2?36GHz is designed.The PLL chip with integrated VCO is used to output the Ku-band signal,and then the output signal of the Ka-band is reached through the subsequent filtering and amplification and frequency multiplication.The output power of the LO module is 8.8dBm at 32GHz,the phase noise is less than-90dBc/Hz at 1 k Hz,and the integrated phase noise is-42dBc of 1 k Hz ?10 MHz,which meets the design index requirements.Then,through the link budget and simulation of the transceiver front-end,and the design and testing of the main components such as low-noise amplifier,power amplifier,mixer,filter,etc.,the physical processing and testing of the single-channel transceiver front-end are completed.The RF passband of the front-end is 38?40GHz and the IF channel bandwidth is 400 MHz at 5.8GHz.For transmitter front end,the in-band gain is about 23dB,the in-band gain flatness is about 3dB.For receiver front end,the in-band gain is about 21dB,the in-band gain flatness is about 3dB.In this paper,the performance parameters of the transceiver channel is also tested,such as 1d B compression point,third-order intercept point,out-of-band spurious,EVM,ACPR,etc.The test results show that the front end of the millimeter wave transceiver meets the design index requirements.