Design And Development Of Wideband Digital-Radio Frequency Transmit Evaluating System In Mobile Base Station

With the popularity of the fourth generation mobile communication technology,more and more people begin to accept and use this new technology.However,as the rising of mobile internet and the increasing of wireless multimedia services,4G mobile communication has gradually failed to meet the needs of mankind.It is expected that by 2020s,faster,more widely available and more convenient 5G mobile communications will be available,so,the high wideband digital radio frequency(RF)transmission mechanism needed in 5G mobile communication has become the main research direction to solve the high load of microcell base station network.This thesis designs a wideband digital to radio-frequency transmitting test system of which is developed for the 4G/5G mobile network base station.The system module coupling the signal generator which can generate any narrowband and wideband signals,and the RF which can generate wideband digital/RF signals with 600 MHz continuous radio frequency spectrum,and can test various radio frequency transmitting communication modes of mobile base stations.The test services can be provided for the communication protocols and hardware performance of 4G/5G mobile communication base stations.This thesis analyzes the current development of mobile communication technology,and the importance of upgrading to 5G,and carries out a detailed research on the high broadband digital RF conversion test technology in mobile base station which is based on the company's actual project.The overall design requirements of wideband digital RF transmitter testing system are presented.According to the requirement of hardware design,the key chip is selected and the hardware solution of the system is put forward.The main board high speed signal generator circuit.high speed digital-to-analog converter circuit,radio frequency transmitting circuit,clock regulating circuit and power management circuit are designed in detail..In the process of circuit design,the working principle of the module,the design outline and the key PCB layout and wiring are introduced in detail.According to the requirement of software design,the software development and configuration environment is established.The parameter configuration and system simulation test are carried out by using MATLAB simulation software and GUI configuration software,and the ana log-to-digital conversion is realized.System clock and radio frequency attenuation and other key indicators of control.After the system design is finished,the TDSCDMA protocol and LTE protocol in the mobile communication protocol are used to test the system.The test results of ACPR and EVM performance shows that the system meets the design requirements.It accords with the test of various broadband digital RF discovery system of mobile base station,and has broad market value and practical scientific research value.