A novel method used for the performance analyzing of channelestimation in time-varying fast fading channel-equivalent channelanalysis method

摘要

In a time-varying fast fading channel, due to the influence ofamplitude fading and fast phase changing, the performance of QAM systemwas deteriorated seriously, it is also the main reason that restrainshigh-dimension modulation from use in fast mobile communications. Inorder to solve this problem, many estimation methods were presentedpreviously. As is known, the process of channel estimation ispractically that of compensation of the channel characteristic. So, inanalyzing the performance of various channel estimation methods one alsoanalyzes the equivalent channel after compensation. The characteristicsof the equivalent channel after compensation is examined in the courseof equivalent channel estimation. This method named the equivalentchannel analysis method is introduced. By using this method, the systemperformance after using channel estimation is only a function of theDoppler shift and correlative coefficient of channel, and depends on thechannel estimation method. We only need to calculate the correlativecoefficient of two neighbouring symbol, we can obtain the relationformula between the error probability and Doppler shift using channelestimation, so it simplifies the analysis of the systemperformance