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The assumption of additive white Gaussian noise (AWGN) to model measurement is not valid since many applications such as in RF power measurement the noise is colored with 1/f spectrum characteristics. With this characteristics, the assumption of independently identically distribution (IID) used in signal detection and estimation becomes not valid. The autocorrelation function and power spectrum can...
This paper considers measuring brain functional connectivity using mutual information (MI). First, we explain the advantage of MI based analysis over the conventional correlation based analysis. Second, we propose a novel approach for MI estimation by exploiting kernel-based probability density function (pdf) estimation and optimization under the maximum likelihood criteria. Finally, the proposed...
This paper provides a general introduction in the field of estimation of probability density function (pdf) of data using a neural network and proposes detailed research of instruments for data preprocessing. In the first section of the research we give a review of current methods and instruments to solve the problem of pdf estimation, highlight their advantages and disadvantages and explain our decision...
A compensation-based user scheduling (CBUS) for multiuser multi-input multi-output (MU-MIMO) systems with delayed feedback channel state information (CSI) is proposed. To cope with the great performance degradation caused by imperfect CSI in the selective transmission/ selective combining (ST/SC) transceiving systems, we propose the CBUS algorithm, which can effectively alleviate the effect of time...
Detecting abnormal usages in intelligent systems, especially in smart home systems, is an important task. By exploring log data, useful information and patterns can be discovered which may help users/organizations to better understand the usage of their appliances and to distinguish unnecessary usages as well as abnormal problems which can cause waste, damages, or even fire. This work proposes several...
Traditionally, the phase of an ideal complex circular random electromagnetic fields is modelled by a uniform distribution. We show that the phase of the Cartesian component of a more general complex elliptic random field exhibits a distribution that depends on the I/Q noncircularity coefficient and the I/Q correlation coefficient. Theoretical distributions are derived and validated experimentally,...
The preamble is one of the indispensable signals in order to discriminate the desired signal from the others. The pseudo-noise (PN) sequences can be used as a part of preamble because of its outstanding correlation properties. One of good preamble detection algorithms for PN sequence is an improved composite pseudo-noise correlation (ICPC) method. In this paper, we focus on the analysis of the probability...
Multiple-input multiple-output (MIMO) systems can provide a noticeable improvement in channel performance. Nevertheless some perturbances affect the capability of this technique to get the expected improvement. Due to the use of multiple antennas at the same front-end and their close spacing the so called antennas correlation effect appears. Antennas correlation can drastically affect the channel...
In this paper, we developed a mathematical model for a single-hop relay-based communication channel. Assuming the transmitter-to-relay and receiver-to-relay channels are non-line-of-sight flat fading channels, we show that the real and imaginary components of the combined single channel have Laplace probability density functions. We, therefore, develop a complex Laplace autoregressive process (AR)...
In this paper, we show a convenient way of generating a Laplace process of a desired autocorrelation. Our approach is based upon the fact that the real or imaginary component of the product of two independent complex Gaussian random variables has a Laplace marginal probability density function (pdf). We, therefore, generate a Laplace process by multiplying two independent complex Gaussian autoregressive...
In this work, we analyse the performance of Cognitive Radio Spectrum Sensing (CRSS) systems with multiple receiving antennas considering the effect of correlation among fading branches. Exact closed-form expressions for the average detection probabilities (P̅D) are derived employing Probability Density Functions (PDF) approach for n.i.i.d.-L number of diversity branches over Nakagami-m fading channels...
Article deals with synthesis and analysis of detector of fractal signal at the background of non-correlated Gaussian noise. Model of signal is fractional Brownian motion (fBm), which describes many types of signal particularly flicker-noise. Expression for likelihood ratio is given being based on fBm models in time and spectral fields. This expression is a sufficient statistics for many problems of...
The algorithm of synthesis of a two-point distributed object model has been treated. Algorithm permits to determine the ability to replace the two-point distributed object model, also to calculate the parameters of the model: position of model emitters, the signal power received on its transducers and the autocorrelation and cross-correlation functions of quadrature components of the signals that...
This paper addresses the problem of rate selection for the cooperative hybrid automatic repeat request with chase combination (HARQ-CC) system, where time correlated Nakagami-m fading channels are considered. To deal with this problem, the closed-form cumulative distribution function (CDF) for the combine SNRs through maximal ratio combining (MRC) is first derived as a generalized Fox's H̄ function...
It is well known that a bandlimited signal can be uniquely determined from nonuniformly spaced samples, provided that the average sampling rate exceeds the Nyquist rate. However, reconstruction of the continuous-time signal from nonuniform samples is more difficult than from uniform samples. This paper develops and compares simpler approximate methods for signal reconstruction from nonuniform samples.
The main objective of this paper is to analyze the statistical wind speed data recorded in Zuwara-Libya during 2007, the wind speed measured at three hub heights of 10m, 30m, and 50m above the ground, wind speeds was taken every 1 minute, were averaged over 10 minutes. The wind speed data set is analyzed using Weibull, Rayleigh, and Gamma distribution. An effort has been made to find out the best...
An efficient measurement procedure is presented for evaluating the probability distribution of the quality (Q-) factor of a mode-stirred reverberation chamber. The method replaces spatial averaging with spectral averaging applied to measurements at just three antenna positions. This avoids the need for spatial scanning across the entire working volume and interior surface of the cavity. Theoretical...
This paper focuses on the impacts of considering batteries state-of-charge (SOC) at the departure time on the demand modeling of plug-in electric vehicles (PEVs). Almost all of the previous researches assumed that PEVs batteries at the departure time are fully charged; however, this assumption is highly questionable because it is probable for a PEV to not be charged every day. The probability density...
This paper deals with the analysis and simulation for composite fading channels, which includes multipath fading and shadowing. Assuming that multipath fading and shadowing are independent, a stochastic reference channel model under composite fading is proposed in terms of a product of Nakagami and lognormal random processes. The probability density function (PDF) and auto-correlation coefficient...
This paper proposes a new systematic methodology to generate random sequences with pre-determined power spectral density and marginal probability density function using Price's theorem for the transformation of the autocorrelation function of jointly Gaussian random variables. Examples and MATLAB simulation illustrate the theory.
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