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This contribution presents a new results on the statistical characterization of PLC-to-DSL interference. The frequency-dependent couplings between power line cables and twisted-pair were estimated from measurements on a large number of residential inside wires. A parametric statistical model based on a mixture of two truncated Gaussian distributions is then set forth. The proposed statistical model...
In this paper, we investigate a downlink model for underlay cognitive radio networks (CRNs). In particular, we assume that the secondary transmitter (SU-Tx) sends common packets to secondary receivers (SU-Rx) under the outage constraint of a single primary user (PU) and the peak transmit power constraint of the SU-Tx. All channels undergo Rayleigh fading. Given these settings, an adaptive transmit...
Application of a powerful statistical tool, the Pearson distribution family, to signal detection problems is investigated in communications literature for the first time. In order to design high performance detectors, we use a method of moments which relies on the Pearson distribution system to estimate probability density function (PDF) of the additive noise or interference. Using the Pearson PDF...
The problem of the detection of a signal in the presence of broad-band noise and interferences that lie in a subspace that is imperfectly known is considered. It is assumed that a basis (or generating set) of the interference subspace is known up to additive white Gaussian noise. This amounts to assuming that each of these basis vectors lies in a cone, the aperture of which depends upon the level...
The Middleton class A interference model is a statistical-physical and parametric model for man-made and natural electromagnetic (EM) interference. In this paper, the efficient estimation of the Class A model parameters based on least square gradient method is derived. The considered estimator converges fast and low-complexity with performance approaching theoretical optima for large data samples...
In this paper, an exact distribution of channel capacity for MISO (Multiple-Input Single-Output) system with co-channel interference is derived from the information theoretical viewpoint. It is found that the MISO channel capacity in the noise-limited channel follows the chi-square distribution, and capacity in the interference-limited channel follows the F-distribution. Using these distributions...
It is well known that, when the channel state information and noise power is perfectly known, the optimal power allocation policy is given by waterfilling procedure. In this paper, we derive the necessary and sufficient conditions for optimal power allocation policy under noise power uncertainty, and express it in terms of Hilbert transformation. A two step algorithm is developed to allocate power...
In this paper, we present a novel approach for pilot-aided channel estimation in OFDM systems with synchronous co-channel interference. The estimator is derived based on the Kullback-Leibler divergence minimization framework. The obtained solution iteratively updates both the desired user's and the interferer's channels, using a combination of linear minimum mean squared-error (LMMSE) filtering and...
Signal detection problems are traditionally viewed as statistical hypothesis testing. In absence of the a priori probabilities, such as in radar, the Neyman-Pearson criterion is used where a certain false alarm probability is set, and the probability of detection is maximised. In signal sensing problems of cognitive radio, the main constraint is to avoid the interference with the primary user. Once...
Cognitive radio technologies are being developed which allow heterogeneous systems to share spectrum access while minimizing interference to improve the overall efficiency of spectrum usage. Interference minimization requires cognitive radio receivers to be able to detect the presence of all other systems competing for spectrum usage, a process often termed "spectrum sensing". This paper...
In many practical applications, noise is non-Gaussian. Heavy-tailed symmetric alpha-stable (SalphaS) distributions have been shown to describe well many natural phenomena and interference in radio engineering, acoustics, communications, etc. For processing signals corrupted by such noise, robust estimators and the corresponding techniques are widely applied. The methods based on a sample myriad (SM)...
Alpha stable distribution has gained much attention due to its generality to represent heavy-tailed and impulsive interference. In such non-Gaussian interference, the detection key is to evaluate the zero-memory nonlinearity (ZMNL) function of locally optimal (LO) detector. Unfortunately, there is no closed form expression for the probability density function (PDF) of alpha-stable distributions. Hereby,...
In this work, a detector scheme for the detection of signal in a group of non-Gaussian narrowband interferences and white Gaussian noise is developed. Since there exists no closed-form probability distribution for this type of disturbance modeling, the key innovation lies in the use of characteristic function rather than the probability distribution to both design and implement the detector. Parameter...
Treating the interference as noise, the paper studies the first derivative of the frontiers which trace the achievable rates region of the 2-user interference channel. The achievable rates region in this case was found to be the convex hull of the union of two regions, each is bounded by a log-defined line. Those log-defined lines are characterized by holding one of the transmitters at full power,...
This paper presents a matched waveform technique for target class identification, i.e., a multiple hypotheses testing (MHT) framework. This technique is shown to improve classification performance of SNR-based matched waveforms derived from a probability-weighted spectral variance (PWSV) approach. The technique, which allows for real-time adaptive waveform transmission, is also shown to be computationally...
The classic mining methods do not suit to mine frequent access patterns in storage system because of their intolerable overhead. This paper analyzes noise - the major factor of low mining efficiency, and proposes a new method-Z-Miner, which employs global-branch-cutting and branch-clustering approaches to cut redundant branches in FP-Tree produced by noise. Compared to the classic methods, the overhead...
To increase the transmission data rate, we propose to use M-ary pulse position modulation (PPM) for transmitted reference (TR) ultra-wideband (UWB) systems. The performance of TR UWB systems employing M-ary PPM is investigated in multipath, multiuser environments without centralized power control. The interference from high-power users is shown to significantly degrade the performance of TR UWB systems...
In this work, we consider the two-user Gaussian MISO interference channel. We derive a criterion for sum-rate optimality of treating interference as noise at the receivers, which generalizes recent results for the SISO case [1]-[3]. In contrast to those results, however, the criterion is not in closed form. For the case where single-mode beamforming is applied at the transmitters, we propose a practical...
Treating interference as noise has recently been shown to be sum capacity achieving for the two-user single-input single-output (SISO) Gaussian interference channel in a low interference regime. In this paper, we characterize the low interference regime for the multiple-input single-output (MISO) Gaussian interference channel. We also provide partial results for the general multiple-input multiple-output...
Recently, the International Telecommunication Union (ITU) has opened the access to radar frequency bands to other users. Widening of this access resulted in a review of the ITU recommendation and tightening of the requirements of protection criteria for radar performance in the presence of unintentional emissions. As a result ITU has recommended the maximum allowable level of interference to noise...
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