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This paper proposes a Doppler resilient modulation approach that can be used in acoustic local positioning systems with Binary Phase-Shift Keying (BPSK) modulated signals for Time-of-Flight (ToF) estimation. The proposed approach is implemented in the receiver and can be performed in parallel with other classic techniques to improve the position estimation process. The technique is based on Differential...
Spectrum sensing plays a critical role in cognitive radio. It autonomously detects the presence of primary users. If the primary users are absent, the spectrum holes can be assigned to secondary users. Different methods have been proposed and employed over the years including the covariance-based detection method. Since signal data generally resides in low dimensional spaces, a method based on a new...
Gender classification technique is a part of the signal processing comprises with feature extraction and behavioural gender modelling. Fundamental frequency and pitch are mostly used as feature for gender detection due to their unique characteristics in voice source. In this study, Gammatone Frequency Cepstral Coefficient (GFCC)-based robust gender classification method has been presented. This study...
The minimum variance distortionless response (MVDR) beamformer is known to be sensitive to steering vector error, especially when the desired signal is present in the training snapshots. The robust capon beamformer (RCB) can deal with this problem, but is computational expensive. A modification of RCB is presented utilizing the low-rank property of the steering matrix which consists of the steering...
A new robust adaptive beamforming based on phase extraction is proposed in this paper. The steering vector (SV) is firstly estimated by iterative procedure, and then the angle sector of the desired signal can be determined by using the phase information of the estimated SV. By using the estimated angle sector, the interference-plus-noise covariance matrix can be calculated by Capon spectral integration...
Identifying and detecting the unknown abnormal sparse signal has become an important issue for distributed networks. In this paper, we proposed a new detection scheme based on convex optimization for wireless sensor networks. Under the Neyman-Pearson testing framework, the detection scheme first estimates the unknown signal by employing the convex optimization at the fusion center. Then the sensor...
A linear array of sensors with small spacing (compared to the wavelength) can be processed with superdirective beamforming. Specifically when applying minimum variance distortionless response (MVDR) weights designed for a diffuse noise-field, high gains are attainable in theory. A classical result relating to the far-field regime states that the gain with respect to diffuse noise (i.e., the directivity...
The calibration of Phasor Measurement Units (PMUs) consists of comparing Coordinated Universal Time (UTC) timestamped phasors (synchrophasors) estimated by the PMU under test, against reference synchrophasors generated through a PMU calibrator. The IEEE Standard C37.118-2011 and its amendment (IEEE Std) describe compliance tests for static and dynamic conditions, and indicate the relative limits in...
In this paper, we introduce an optimal beamformer design that facilitates a compromise between high directivity and low white noise amplification. The proposed beamformer involves a regularization factor, whose optimal value is determined using a simple and efficient one dimensional search algorithm. Simulation results demonstrate controlled tuning of various gain properties of the desired beamformer,...
Superdirective beamformers with uniform circular arrays (UCAs) are often used in communication applications for their steering flexibility and potential high directivity factors (DFs). This paper proposes two classes of subspace superdirective beamformers. The first class is based on the diagonalization of the noise pseudo-coherence matrix with the Fourier matrix while the second one is based on the...
This manuscript presents a robust data-independent near-field beamformer using a linear microphone array. We consider a scenario with a desired sound source and an interferer; our goal in this manuscript is to provide a technique to extract the desired source signal while attenuating the interferer. We formulate the beamformer design problem as a convex optimization problem with additional constraints...
In Cognitive Radio (CR), secondary radios are allowed to use the spectrum allocated to primary radios (PR) only if the spectrum is sensed to be unused by the PR users. Cooperative spectrum sensing is a sensing methodology in which secondary users send their detection results to a central fusion node for global decision. It has been shown that for single node detection, SNR wall provides a hard threshold...
This paper considers an underlay access strategy for coexisting wireless networks where the secondary system utilizes the primary spectrum to serve its users. We focus on the practical cases where there is uncertainty in the estimation of channel state information (CSI). Here the throughput performance of each system is limited by the interference imposed by the other, resulting in conflicting objectives...
In this paper, we consider a joint transmission scheme of coordinated multi-point (COMP) technology in communication networks. In this kind of networks, data can be transmited from multiple points to a user in a time-frequency resource, simultaneously. Because of high signaling and successive delays, channel state information at the transmitter (CSIT) may be incorrect. In this regard, we devise the...
Most of the available phase retrieval algorithms were explicitly or implicitly developed under a Gaussian noise model, using least squares (LS) formulations. However, in some applications of phase retrieval, an unknown subset of the measurements can be seriously corrupted by outliers, where LS is not robust and will degrade the estimation performance severely. This paper presents an Alternating Iterative...
Most existing methods in binaural sound source localization rely on some kind of aggregation of phase- and level-difference cues in the time-frequency plane. While different aggregation schemes exist, they are often heuristic and suffer in adverse noise conditions. In this paper, we introduce the rectified binaural ratio as a new feature for sound source localization. We show that for Gaussian-process...
In this paper, we present a novel resource allocation (RA) algorithm for packet Universal Filtered Multi-Carrier (UFMC) BIC-based communications, the latter being a novel modulation format possibly envisaged to be applied in 5G wireless systems. Assuming the perfect knowledge of the channel and capitalizing on the specific UFMC signal waveform, the proposed RA strategy optimizes the coding rate and...
Sparse, non-negative signals occur in many applications. To recover such signals, estimation posed as non-negative least squares problems have proven to be fruitful. Efficient algorithms with high accuracy have been proposed, but many of them assume either perfect knowledge of the dictionary generating the signal, or attempts to explain deviations from this dictionary by attributing them to components...
In this paper a robust beamforming method is proposed, which can effectively overcome the influence of DOA(direction of arrival) mismatch. The proposed method exhibits the enhanced robustness of the beamformers based on analysis of linear constrained minimum variance beamformer. Then the support vector regression (SVR) algorithm is applied to the robust beamforming, which is based on the principle...
Improving the execution time and the numerical complexity of the well-known kurtosis-based maximization method, the RobustICA, is investigated in this paper. A Newton-based scheme is proposed and compared to the conventional RobustICA method. A new implementation using the nonlinear Conjugate Gradient one is investigated also. Regarding the Newton approach, an exact computation of the Hessian of the...
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