The Key Technology Research Of TD-LTE Broadband Radio Channel Measurement And Parameter Estimation Under The High-speed Railway

With the continuous development of modern society,the high-speed rail as a new type of efficient transport way,constantly promote the rapid development of economy in our country.Now,our country's high-speed railway operation range is still in constant growth,covered cities continue to increase.High-speed railway has now become an important way to national traffic operations indispensable.The rapid development of high speed railway,make traditional railway communication system already cannot satisfy the new requirements.Research using more advanced high-speed rail system on the LTE communication system communication service has attracted more and more attention.Therefore,this study in order to provide adequate and accurate theoretical support in the future high-speed railway wireless communication system design,launched on the channel speed railway environment measurement and channel modeling study.In the implementation of this paper,built the wireless channel measurement platform based on the environment of high speed railway,and has carried on the field of high speed railway channel measurement,field measurements environment has chosen to represent high speed railway through the terrain,viaduct.In the process of processing measurement data,the research of channel estimation algorithm is suitable for high speed railway environment.This paper selects the commonly used three kinds of channel estimation algorithm carries on the analysis comparison,including spectral estimation algorithm,parameter subspace estimation and parameter estimation method.After comprehensive comparison algorithm complexity and precision of the advantages and disadvantages,choose SAGE algorithm for channel estimation algorithm under the environment of high speed railway.After the research using scientific and reasonable mathematical methods to extract the characteristic parameters of the wireless channel,including large scale and small scale parameters.At the end of the paper gives the viaduct,mountain and open scenario shows different wireless channel fading characteristics,based on the channel to extract the parameters corresponding to the wireless channel model is constructed.Based on this study the practice of measuring and mathematical results,presented at the high-speed railway environment suitable channel measurement program,channel estimation algorithm to get the channel parameter results have important reference for the design of future high-speed railway wireless communication system.