Research On Ranging And Peak-To-Average Power Ratio Reduction In Mobile Broadband Multi-Carrier Commuincation Systems

Broadband Wireless Multimedia originated from the research project of next generation wireless communication in China.The objective of BWM is to develop a kind of effective and low cost methodology to achieve "Triple Play" from traffic platform,core network,wireless access network,air interface to terminal.In BWM system,uplink PHY layer adopts DFT-S-GMC technology(DFT-Spread General Multi-Carrier).DFT-S-GMC uses the technology of non-critically sampled filter banks,which has the nature robust to frequency offset,MUI and good performance of PAPR/CM.Based on the existing study of DFT-S-GMC,the performance of the problems of initial ranging and uplink PAPR are studied and deduced theoretically in this thesis.In the aspect of PHY layer of ranging,PAPR/CM and time-domain correlation of ranging signals in Mobile WiMAX and DFT-S-GMC,the result is that PAPR/CM of Zadoff-Chu based GMC ranging signal is better than WiMAX and the auto-correlation peak is sharper.Then receiver algorithms of ranging signal of Mobile WiMAX and DFT-S-GMC are deduced,analyzed and simulated:1)From the perspective of correlation detection,principles of time-domain cross-correlation,frequency-domain cross-correlation and frequency-domain differential cross-correlation are deduced.A low-complexity frequency-domain cross-correlation ranging detection algorithm by down sampling is presented;2)From the perspective of detection threshold,various adaptive detection signal item and noise-plus-interference item are showed and analyzed.To utilize the features of cyclic-shift of DFT-S-GMC ranging signal,adaptive computation of noise-plus -interference item is presented based on concept of peak-filtering,and a new ranging detection algorithm is presented.Simulation show better performance than traditional method adopting ensemble average correlation power.3)From the perspective of multiple antenna diversity and combination,two methods of selective diversity and equal gain combining are given and applied to ranging detection and uplink timing synchronization of DFT-S-GMC.By simulation,the conclusion come to that equal gain combining have smoother false alarm and better detection performance.4)From the perspective of CM and time-domain correlation of ranging signal,grouping method of Zadoff-Chu sequences in DFT-S-GMC is presented used for different ranging and bandwidth request.