METHOD AND DEVICE FOR CHANNEL ESTIMATION, AND CORRESPONDING COMPUTER PROGRAM PRODUCT

摘要

An embodiment of the time-variant channel estimation in an OFDM transmission system envisages the operations of: a) determining the received signal vector Yj,k for one or more of R receiving antennas, j=1, . . . , R, and at the current time instant k together with the frequency-domain channel-estimate vector Ĥj,k−1 at a preceding time instant k−1 and for each antenna j of one or more of R receiving antennas; b) producing a first estimate Âk of the transmitted digital symbols at the current time instant k on the basis of the aforesaid frequency-domain channel-estimate vectors Ĥj,k−1 at the preceding time instant k−1; c) computing an updated version of the frequency-domain channel-estimate vectors Ĥj,k at the current time instant k and for each antenna j of one or more of R receiving antennas on the basis of the received signal vectors Yj,k at the current time instant k and for each antenna j of one or more of R receiving antennas, using the aforesaid estimate Âk of the transmitted digital symbols at the current time instant k as set of known transmitted digital symbols; d) using the aforesaid updated version of the frequency-domain channel-estimate vectors Ĥj,k at the current time instant k and for each antenna j of one or more of R receiving antennas, for equalizing the paths of the transmission channel and decoding the received signal vectors Yj,k at the current time instant k and for each antenna j of one or more of R receiving antennas; and e) storing the updated versions of the channel-estimate vectors for using them in steps a) and b) at the next time instant k+1.

主权项

1. A non-transitory computer-readable medium having contents which configure an OFDM signal processing system to perform a method, the method comprising:
processing digital transmitted symbols modulating OFDM sub-carriers received via at least one receiving antenna j as a signal vector Yj received over at least one transmission channel represented by a frequency domain channel estimate vector Ĥj, at a sequence of time instants wherein a current time instant k lies between a previous time instant k−1 and a next time instant k+1, the processing including: determining said frequency domain channel estimate vector Ĥj,k−1 at said previous time instant k−1 as well as said received signal vector Yj,k at said current time instant k; producing an estimate Âk of the digital transmitted symbols at said current time instant k based on said frequency domain channel estimate vector Ĥj,k−1 and said received signal vector Yj,k at said current time instant k, each symbol in the estimate Âk having a reliability factor; computing an updated version of said frequency domain channel estimate vector Ĥj,k at said current time instant k based on said received signal vector Yj,k at said current time instant k using said estimate Âk as a set of known digital transmitted symbols based on selecting a threshold number of symbols from estimate Âk that include a combination of symbols having a reliability factor that exceeds a threshold reliability and if the threshold number is not readied then supplementing the selection with a balance of symbols having a reliability factor below the reliability threshold; using said updated version of said frequency domain channel estimate vector Ĥj,k at said current time instant k for equalizing said at least one transmission channel, in decoding said received signal vector Yj,k at said current time instant k, and storing said updated version of said frequency domain channel estimate vector Ĥj,k at said current time instant k for use in processing at said next time instant k+1.