Based On The Dpd Technology Wcdma Transmitter Front-end Design

Three main third-generation mobile communication standards are WCDMA standard in Europe, CDMA2000 standard in the United States and China's TD-SCDMA standard, of which WCDMA has higher spreading gain, larger space for development, the strongest global roaming capabilities, best technical maturity and has an advantage in the future. At the same time, with the development of modern communication system, transmitter power amplifier linearity is decoming an increasing demand. So, digital pre-distortion technology (DPD) has also become a hot research topic.This paper has a in-depth study on WCDMA transmitter ront-end based on digital technology Digital Predistortion (DPD) .First, an overview of the WCDMA communication system and its main technical indices.Secondly, make a simulation analysis on the basic principles of DPD technology. Then, make a united simulation platform with use of MATLAB and ADS simulation software. Based on this simulation patform, analyze various parts in the transimitter structure(reconfigurable filter, analog quadrature modulator, LO phase noise, emission filters, nonlinear amplifiers, anti-alias filter, etc.),and give their impact on DPD and transmitter performance.Thirdly, according to the conclusions of the previous simulation, conduct a systematic analysis of the transmitter. Give system analysis of transmitter linearity, noise, spurious, and finally give requirment of the various parts in the transimtter, determine the final scheme,give a simulation of the total transmitter link.Fourthly, in accordance with the conclusions of the previous analysis, conduct the device selection, give simulation analysis of . reconfigurable filter, anti-alias filter,MGA62563,SXA389B,etc.Finally, measure the overall performance of the transmitter. Test result shows that the system has achieved the objectives and requirements.