Patent ID: 8811927

Claim:
A method of estimating a plurality of estimated transfer functions corresponding to a plurality of wireless channels in a multiple-input system that includes a receiving antenna receiving a time-domain signal corresponding to a plurality of signals transmitted from a plurality of transmitting antennas, the method comprising: a transform unit transforming the time-domain signal into a frequency-domain signal; a channel estimation unit estimating, based on the frequency-domain signal and a frequency-domain pilot signal, a combined transfer function corresponding to a plurality of transfer functions of respective channels between the plurality of transmitting antennas and the receiving antenna; and a channel separation unit separating the combined transfer function into a plurality of estimated channel transfer functions by convolving, in the frequency domain, the combined transfer function with a plurality of windowing functions, wherein the method further comprises one or more of the following steps: convolving, in the frequency domain, the combined transfer function with a respective frequency-domain representation of a windowing function; phase-shifting each one of the plurality of windowing functions, such that a phase of each windowing function is different than the phase of each other windowing function; circularly convolving, in the frequency domain, the combined transfer function with the respective frequency-domain representation of the windowing function; and circularly convolving, in the frequency domain, components corresponding to middle subcarriers of the combined transfer function with the respective frequency-domain representation of the windowing function, and (b) linearly convolving, in the frequency domain, components corresponding to end subcarriers of the combined transfer function with the respective frequency-domain representation of the windowing function.