Comparing the performances of least mean squares based multirate adaptive filters

In this study, sign-error, sign-data, and sign-sign modifications of the multirate least mean squares (LMS) filter are proposed as an alternative to the existing multirate LMS and normalized LMS filters for reconstructing the high rate desired signal from its several low rate noisy observations. The performance of all the existing and the proposed methods are compared by using an adaptive noise cancellation simulation example applied to an audio signal. It is seen from the simulation results that some of the proposed methods lead to better results than the existing ones especially in the convergence speed sense. © 2016 IEEE

Adaptive noise cancellation with a multirate normalized least mean squares filter

Multirate adaptive filtering is related to the problem of reconstructing a high-resolution signal from two or more observations that are sampled at different rates. A popular existing method for solving this problem uses the multirate adaptive filter structure that is based on the least mean squares (LMS) approach. However, its low convergence rate restricts the use of this method. In this study, a multirate normalized LMS (NLMS) filter is proposed as an alternative to that of LMS based filter, for the reconstruction of the high-resolution signal from several low-resolution noisy observations. In the simulation example performed on an audio signal, it is observed that the proposed method leads to the better results than the existing method especially in the convergence rate. © 2015 IEEE

An hybrid method for statistical multirate high-resolution signal reconstruction

In this study, a hybrid method is proposed for the reconstruction of a high-resolution (HR) signal from a set of its noise corrupted low-resolution (LR) versions. In this hybrid method, noise reduction based on the empirical mode decomposition and Savitzky-Golay filtering is applied to the LR observations. Afterwards, zero-interpolated HR signals are obtained by performing up-sampling and time shifting on each LR signal. A one HR signal is produced by combining the zero-interpolated HR signals to a specified rule. To eliminate the ripple effect, finally, median filtering is applied to the resulting HR signal. As compared to the work employing Wiener filters, the proposed method comes into prominence as is it does not require any statistical information. It is demonstrated by simulation examples that the proposed method leads to satisfactory results in the reconstruction of HR signal. © 2014 IEEE

AN APPROACH TO POWER RATIOS AND PROBABILITIES AND INTERPRETATIONS OF THESE QUANTITIES IN RECTANGULAR QUANTUM WELLS

This study focuses on power and probability expressions belong to normalized frequency and normalized propagation constant of electric field in the rectangular quantum well. The confinement effects of the properties of confined carriers in the energy levels have been studied. Normalized frequency and normalized propagation constant are especially functions of the ordinates and abscissas of the energy eigenvalues for electrons or holes in the rectangular quantum well in the normalized coordinate system (?-?). Our calculations also give more accurate results, and present more sensitive comparative examples