Channel estimation using a chirp signal and the Fractional Fourier Transform

摘要

Channel estimation using a chirp signal and the Fractional Fourier Transform (FrFT) is disclosed. A relatively short chirp may be transmitted, and its received components may be converted to tones using the FrFT, from which the channel tap magnitudes and delays can readily be computed. This may involve measuring peaks in the rotated spectrum, measuring the time between the peaks, and mapping the time in the rotated plane back to the original time. Such a technique has various advantages over conventional channel estimation techniques, such as providing high accuracy even in very poor multipath environments and requiring relatively few samples of a chirp, which hence can reduce pilot overhead.