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The binormalized data-reusing least mean squares (BNDR-LMS) algorithm has been recently proposed and has been shown to have faster convergence than other LMS-like algorithms in cases where the input signal is strongly correlated. This superior performance in convergence speed is, however, followed by a higher misadjustment if the step-size is close to the value which allows the fastest convergence...
This paper deals with the compensation for nonlinear distortions introduced by power-efficient amplifiers on linear modulations by means of equalization. In our approach, we employ a Decision-Feedback Equalizer (DFE) based on the Generalized Cerebellar Model Arithmetic Computer. The new scheme is compared with the conventional Linear DFE, the Volterra and the Multi-Layer Perceptron-based DFE in terms...
The paper addresses the problem of fast and accurate estimation of sinusoidal frequencies from noisy measurements. An iterative algorithm of complexity O(n log n) is proposed that produces accurate frequency estimates whose precision can be arbitrarily close to that of maximum likelihood. Convergence and accuracy of the algorithm are ensured by a rigorous mathematical analysis which includes statistical...
A novel adaptive recursive algorithm is proposed for estimating the interpath delay of a radiated signal in a multipath environment. Using LMS-type adaptation, the estimator is computationally efficient and it provides direct measurements of multipath gain and delay on a sample-by-sample basis. The convergence dynamics and variances of system parameters are derived. It is shown that the optimal performance...
We propose two structures and theirs associated algorithms designed to solve the blind source separation problem in the presence of noise and interferences. Both structures exploit the non convexity of the Constant Modulus cost function, finding its multiple local minima. A convergence analysis shows that both schemes achieve the desired solution, separately extracting the sources of interest while...
The ERLE (echo return loss enhancement) iterates greatly up and down, if the adaptive filter coefficients are continuously adjusted in disregard of the reference signal power fluctuation. This paper presents a method of always maintaining the specified ERLE, even when the adjustment is continued in voiceless noise terms. The method is based on the ‘summatìonal’ NLMS (normalized least mean square)...
A new iterative speech enhancement scheme that can be seen as an approximation to the Expectation-Maximization (EM) algorithm is proposed. The algorithm employs a Kalman filter that models the excitation source as a spectrally white process with a rapidly time-varying variance, which calls for a high temporal resolution estimation of this variance. A Local Variance Estimator based on a Prediction...
In this paper, the pulse shape design for various communication systems including PAM, FSK, and PSK is considered. The pulse is designed by imposing constraints on the time and frequency domains constraints on the autocorrelation function of the pulse shape. Intersymbol interference, finite duration and spectral mask restrictions are a few examples leading to convex sets in L2. The autocorrelation...
The Self-Organising Oscillator Network (SOON) provides a novel way for data clustering [1, 2]. The SOON is a distance based algorithm, meaning that clusters are determined by a distance parameter, rather than by density distribution, or a pre-defined number of clusters. Repeated experiments have highlighted the sensitivity of this algorithm to the initial selection of phase values and prototypes....
An l∞ norm based Source Separation Method has recently been introduced [1, 2], with the corresponding subgradient based algorithm that has a simple update rule. In this article, we propose a moving window modification to this algorithm, where instead of a long fixed window, a shorter length moving window is used. The simulation results for different blind source separation setups suggest that a significant...
We consider symbol rate estimation of an unknown signal linearly modulated by a sequence of symbols. We rely on the received signal is cyclostationarity, and consider an existing estimator obtained by maximizing in the cyclic domain a (possibly weighted) sum of modulus squares of cyclic correlation estimates. Although widely used, this estimate seems not to have been studied rigorously when the number...
In this paper we introduce a general thresholding operator based on multi wavelets. It offers the flexibility that multiwavelet coefficients generated by different component multiwavelet functions in a multiwavelet vector can be filtered by different thresholding rules. A convergence result of the proposed operator is given. Numerical results for denoising simulation are also presented for showing...
A novel adaptive filter algorithm based on the linear prediction property of sinusoidal signals is proposed for estimating the frequency of a real tone in white noise, assuming that the noise power is known a priori. Using the least mean square algorithm, the estimator is computationally efficient and it provides explicit frequency measurements on a sample-by-sample basis. Convergence behavior and...
In this paper we present an iterative algorithm to jointly optimize the source and relay power allocations for a general relay transmission system, i.e. the broadcast-and-multiaccess (BMA) multicarrier relay system, where the source transmits in two time-slots. Under the indoor power line communication environment, we examine the issue of minimization of the total network transmission power subjecting...
The use of repeater for the support of high data rate data transmission and the extension of cell coverage is imperative for the Wibro system, which is based on the IEEE 802.16e standardization. Generally, if the separation between transmitting and receiving antennas is not sufficient, the oscillation of repeater and the interference due to the feedback signals from original transmitted signal may...
In ultra dense heterogeneous networks (HetNets), the interference becomes more serious since multiple small cells coexist in the coverage area of the macrocells and share the same spectrum. An efficient interference coordination method is adjusting the transmit powers of all cells in a cooperative way. However, under practical serving cell selection rules in which serving cells of users alter with...
In this work, we consider a network composed of several single-antenna transmitter-receiver pairs in which each pair aims at selfishly minimizing the power required to achieve a given signal-to-interference-plus-noise ratio. This is obtained modeling the transmitter-receiver pairs as rational agents that engage in a non-cooperative game. Capitalizing on the well-known results on the existence and...
Numerous environmental sources of noise and distortion can degrade the quality of the speech signal in a communication system. This study explores the effects of these intrusive sounds on speech applications and introduces some techniques for reducing the influence of noise and, enhancing the acceptability and intelligibility of the speech signal. In this paper, a noise reduction system uses single...
Functional near-infrared spectroscopy (fNIRS) is a non-invasive technique for detection of brain activity by measuring the absorbed quantity of near-infrared light. Absorbed light corresponds to concentration changes in oxygenated (HbO) and de-oxygenated (HbR) hemoglobins in blood during brain activity. Recently, some research is presented on real-time fNIRS-BCI applications to estimate the parameters...
An acoustic noise cancellation is an approach used for reduction of additive noise in the speech signal. Normalized Least Mean Square (NLMS) algorithm is the most popular adaptive filter algorithm for noise cancellation. But in NLMS algorithm, selection of step size and filter length of adaptive filter for different type of noise with different noise level (dB) that gives maximum SNR is difficult...
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