Estimation the Impulse Response of a Wireless Channel Using an Orthogonal Subband Basis

Abstract

The article discusses a method for estimating the impulse response of a communication channel based on signal-code structures formed using an orthogonal subband basis. The orthogonal basis consists of eigenvectors of a subband matrix calculated for a given frequency range with a minimum level of out-of-band radiation. For an orthogonal basis, eigenvectors are selected whose eigenvalues are close to or equal to one. Estimation of the channel impulse response is based on solving a system of linear equations, where the transmitted information is known. Since out-of-band emission is minimal, this basis is optimal for channel estimation. The orthogonality of the vectors and their occupation of the entire frequency range allows the use of only one pilot signal to estimate the impulse response of the entire channel. The effectiveness metric of the proposed method is the standard deviation between the obtained estimate and the applied distortion. The experimental results show the effectiveness of the developed method for estimating the impulse response of a channel in the presence of different levels of Additive white Gaussian noise (AWGN).