Blind channel estimation method based on OFDM (orthogonal frequency division multiplexing) signal cyclostationary features

Abstract

The invention discloses a blind channel estimation method based on OFDM (orthogonal frequency division multiplexing) signal cyclostationary features, and the method is characterized in that on a fixed cycle frequency, z-transform of a delay variable Tau in a period spectrum function of an OFDM received signal is analyzed, and the accurate estimation of channel information is realized by selecting two different correlation values of the z-transform of the delay variable Tau, finally utilizing H(z) containing channel amplitude and minimal phase information and utilizing the existing least square method. Only the frequency spectrum information of one cycle frequency is adopted by the method, the quantity of the cycle frequency is reduced, so that the utilization rate of the frequency resource is effectively improved, the accuracy of the channel estimation is improved, and the performance of the method is obviously better than that of the existing blind channel estimation method through simulation verification; and by analyzing the energy distribution regulation of the self-correlation function of the OFDM received signal, the frequency spectrum information centralizing partial energy is adopted, the rest frequency spectrum information is set as zero, and the quantity of matrixes to be constructed is reduced, so that the calculation complexity is reduced.

Description

[0001] This application is a divisional application of the original application number 200910157038.9 for a patent application for invention. Its filing date is December 31, 2009. The title of the invention is "A Blind Channel Estimation Method Based on Cyclostationary Characteristics of OFDM Signals". technical field [0002] The present invention relates to a channel estimation method, in particular to a blind channel estimation method based on OFDM signal cyclostationary characteristics. Background technique [0003] With the advent of the post-3G era, Orthogonal Frequency Division Multiplexing (OFDM, Orthogonal Frequency Divided Multiplexing) system, as its key technology, has attracted great attention due to its advantages of low cost and high frequency band utilization, and has become the current wireless Research hotspot in the communication field. Orthogonal Frequency Division Multiplexing (OFDM) system converts high-speed serial data streams into low-speed sub-data ...

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Problems solved by technology

[0010] The above double k method selects two non-zero cyclic frequencies to construct the periodic spectral function of the received signal at each cyclic frequency, and uses the two periodic spectral functions to estimate the phase and amplitude information of the channel, which effectively improves the accuracy of channel estimation. However, this method needs to use two cyclic frequencies to estimate the channel, which greatly reduces the utilization of spectrum resources and reduces the estimation performance of the system.

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