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In order to enhance the performance of the existing beamformer-based direction-of-arrival (DOA) estimation methods, a novel DOA estimation method based on the sparse and low-rank decomposition of the sample covariance matrix is proposed. First, the sample covariance matrix is divided into the covariance matrix of the desired signal and interference as well as that of noise. The first component is...
The histogram algorithm based on sound intensity having been widely used to estimate the azimuths of underwater acoustic targets. The advantage of this algorithm is that all we need is a single vector hydrophone to distinguish multiple targets' azimuths. The histogram approach acquiesces in that the acoustic pressure is perfectly correlated with the particle velocity. However, the sound field excited...
In this paper, an improved joint processing algorithm based on Estimation of Signal Parameters via Rotational Invariance Technique(ESPRIT), which can efficiently combine acoustic pressure and analytic velocity, is proposed to estimate azimuth angle. This method can be applied in acoustic vector sensor array (AVSA) of any formation. A novel cross-covariance matrix of acoustic pressure and analytic...
The direction-of-arrival (DOA) estimation for the long-distance underwater acoustic sources usually suffers from low levels of signal-to-noise ratio (SNR) and insufficient snapshot data. Therefore, a novel signal self-nulling based DOA estimation algorithm is proposed. First, assume that the angular sector, where the desired signal is located, is known. Then, the beampattern of the minimum variance...
In recent years emerging ride-on-demand services (eg., Uber or Didi) are penetrating into the market of traditional taxi service. In these new services mobile devices are a key enabler: they serve as the intermediary between passengers/drivers and the service provider, tracking the locations and behavior of both passengers and drivers. On the other hand, the use of mobile devices also help us to capture...
Nowadays the estimation of crowd density and people counting is a great focus under public security affairs in surveillance. A scheme for crowd counting estimation based on linear regression function is proposed in this paper. In the proposed scheme, the Light Effect Suppression Model (LESM), which effectively reduces the sensitivity to illumination change, is applied to extract the foreground. Besides...
Significant wave height (SWH) is one of the major ocean altimetry products. This paper proposes a fast algorithm in retrieving the SWH from altimeter waveform. The idea is to differentiate the echo waveform and acquire a Gaussian-shape waveform. Then the standard deviation of the Gaussian function is computed directly and the standard deviation of the scatter probability density function (hence, SWH)...
Over the past decades, many phase unwrapping algorithms have been developed and formulated for overcoming the problem of phase ambiguity. In this paper, a novel ambiguity reduced phase unwrapping method is proposed, which unwraps the linear combined phases instead of the instantaneous phases, and thus substantially reduces the degrees of ambiguity. It turns out that the ambiguity-reduce phase unwrapping...
With increasing interest in the effect of postural changes on arterial blood pressure and vascular properties, it is important to understand effects of pressure-dependent arterial compliance. This study investigates effects of pressure-dependent compliance on pulse wave velocity (PWVar), pressure wave shape, and transmission characteristics in an arterial model of the human arm from heart to radial...
Peer-to-Peer (P2P) applications have become increasingly popular in recent few years, which bring new challenges to network management and traffic engineering (TE). As basic input information, P2P traffic matrices are of significant importance for TE. Due to excessively high cost of direct measurement, a lot of studies aim at modeling and estimating general traffic matrices, but few focus on P2P traffic...
In this paper, we propose a unified framework to examine the effect of SNR mismatch on the performance of turbo algorithms, such as turbo equalization and turbo decoding. The proposed framework is based on a general model for a biased estimate of the signal-to-noise ratio (SNR) of the channel. It is shown how the estimation model can unify previously SNR mismatch models, which become special cases...
Very high analog-to-digital (A/D) sampling rate is a key problem to be solved in a ultra-wideband (UWB) communication system. To reduce the A/D sampling rate, a novel low sampling rate receiver based on nonuniform sampling in the frequency domain is proposed. The incoming signal is divided into several subchannels, and signals at some subchannels are sampled at nonuniform sampling rates in the analog-to-digital...
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