Channel estimating method

Abstract

The invention discloses a channel estimation method, comprising: a. carrying out conventional channel estimation on usable pilot frequency located in usable sub-carrier scope, setting virtual channel frequency response estimation for virtual pilot frequency located in virtual carrier scope to assure smooth transition, thus acquiring channel frequency domain response estimations in all pilot frequency positions; b. carrying out inverse Fourier transform for the channel frequency domain response estimations got from step a, to get time domain response estimations; and c. cutting and interpolating zero to the time domain response estimations got from step b, and then carrying Fourier transform to get complete channel frequency domain response estimation. The invention solves the following problems in current technology: large channel estimation error, and obvious channel estimation error in sub-carrier position near virtual carrier. The inventive scheme can effectively reduce, even eliminate the effect of virtual carrier to channel estimation performance, and especially decrease the channel estimation error of sub-carrier position near virtual carrier.

Description

technical field [0001] The invention relates to the technical field of wireless mobile communication, in particular to a channel estimation method. Background technique [0002] Orthogonal frequency division multiplexing (OFDM) technology has the ability to resist inter-symbol interference (ISI) and can provide high spectral efficiency at the same time, so it is regarded as the most likely transmission technology for the next generation of wireless mobile communication systems. It has been widely used in many fields such as digital subscriber loop, digital audio / video broadcasting, wireless local area network and wireless metropolitan area network. [0003] In order to ensure good performance of OFDM communication system in wireless mobile channel environment, it is necessary to estimate the time-varying multipath fading channel as accurately as possible. The quality of channel estimation plays a key role in the performance of OFDM system. [0004] Currently, the channel e...

AI Technical Summary

Problems solved by technology

This scheme needs to assume that the timing synchronization is completely accurate in order to determine the position of zero complement in the time domain, but the timing synchronization in the actual OFDM communication system will inevitably have errors

And the channel estimation results obtained by this method still have large errors in the subcarriers near the virtual carrier

[0015] To sum up, since there must be a virtual carrier in the actual OFDM communication system, the channel estimation error obtained by the current DFT-based channel estimation method is relatively large, especially at the position of the subcarrier near the virtual carrier, the channel estimation error more obvious

However, the existing two improved methods still cannot solve the above problems well.

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