US 8,275,053 B2 · Apparatus and method of estimating channel based on channel delay spread in mobile communication system

Abstract

The present invention relates to an apparatus and method of estimating a channel based on a channel delay spread in a mobile communication system. Pilot subcarriers are inserted between data subcarriers at predetermined intervals to estimate a channel at locations of the pilot subcarriers. An approximate channel delay spread value is estimated by using an autocorrelation value of a pilot signal. Then, a channel for data subcarriers between the pilot subcarriers is estimated by using a Wiener finite impulse response (FIR) filter that has a separate coefficient according to the estimated delay spread value. Accordingly, by changing the Wiener FIR filter coefficient according to the delay spread value of the channel, it is possible to estimate the channel so as to be adaptive for a change of the channel over time. Since the filter coefficients, which are calculated in advance, are used, it is possible to reduce the amount of calculation required when calculating the filter coefficients. As a result, an apparatus for estimating a channel can be easily achieved.

Claims9

Dependent claims

An apparatus for estimating a channel based on a channel delay spread, the apparatus comprising:

a Fast Fourier Transform (FFT) converter for performing a Fourier transform on a signal where distortion has occurred;
a channel estimating unit for estimating delay spread values, in a form of a sum between a channel value as a signal component and a white Gaussian noise as a noise component, on a basis of a plurality of channel estimation values corresponding to pilot signals only extracted from the signal on which the Fourier transform has been performed, for outputting a channel estimation value of an entire symbol for the signals where the distortion has occurred by using a column of the channel estimation values estimated for the pilot signals and Wiener Finite Impulse Response (FIR) filter coefficients that are calculated in advance to correspond to the estimated delay spread values, and for selecting the Wiener FIR filter coefficients from a predetermined plurality of Wiener FIR filter coefficients on a basis of a maximum of the estimated delay spread values;
and
a signal correcting unit for compensating for the distortion of the signal on a basis of the channel estimation value of the entire symbol, which is estimated for the signal where the distortion has occurred, and outputs the signals.

1 more element

A method of estimating a channel corresponding to a channel delay spread, the method comprising:

receiving signals where distortion has occurred;
extracting only pilot signals from the received signals;
estimating a plurality of channel estimation values corresponding to the extracted pilot signals;
estimating channel delay spread values in a form of a sum between a channel value as a signal component and a white Gaussian noise as a noise component from the extracted pilot signals;
selecting filter coefficients from a plurality of Wiener Finite Impulse Response (FIR) filter coefficients calculated in advance on a basis of a maximum of the estimated channel delay spread values;
and
estimating channels for an entire symbol of the signals where the distortion occurred on a basis of the selected filter coefficients and the channel estimation values corresponding to the pilot signals,
wherein the estimating of the channel delay spread values includes:
estimating channels for the extracted pilot signals and outputting a column of channel estimation values;
and
estimating the channel delay spread values on a basis of the output column of channel estimation values.

8 more elements

Dependencies are inferred from the claim text.

Apparatus and method of estimating channel based on channel delay spread in mobile communication system

Life of this patent

Apparatus and method of estimating channel based on channel delay spread in mobile communication system

Life of this patent

Abstract

Claims9