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In radar systems, detection performance is always related to target models and background environments. In time diversity systems, the probability of detection is shown to be sensitive to the degree of correlation among the target echoes. In this paper, we derive exact expressions for the probabilities of false alarm and detection of a pulse-to-pulse partially correlated target with 2K degrees of...
In this paper, we analyze the performance of some permutation tests (PTs) under a correlated K-distributed clutter model and nonfluctuating and Swerling II target models. Also, we compare the PTs results against their parametric counterparts under the same conditions. We analyze the detector performances in terms of detection probability (Pd) versus signal-to-clutter ratio (SCR) for different parameter...
Multiple clock cycle hardware implementation (MCI) of a flexible system for space/spatial-frequency signal analysis is proposed. Designed special purpose hardware can realize almost all commonly used two-dimensional space/spatial-frequency distributions (2-D S/SFDs) based on the 2-D Short-time Fourier transformation (2-D STFT) elements. The flexibility and the ability of sharing functional kernel,...
This contribution analyzes the integration of the sphere decoder (SD) in a complete field-programmable gate array (FPGA)-based real-time multiple input-multiple output (MIMO) platform. The algorithm achieves the performance of the maximum likelihood detector (MLD) with reduced complexity. However, its non-deterministic complexity, depending on the noise level and the channel conditions, hinders its...
In this paper we present a novel method for multiframe blind deblurring of noisy images. It is based on minimization of the energy criterion produced in the frequency domain using a recursive gradient-projection algorithm. For filtering and regularization we use the local polynomial approximation (LPA) of both the image and blur operators, and paradigm of the intersection of confidence intervals (ICI)...
Automated crystal orientation measurement (ACOM) in the scanning electron microscope (SEM) is a standard technique of texture analysis (pattern recognition) that is used in materials science. The measurement is carried out by interpreting backscatter Kikuchi patterns, in particular by the extraction of the position of so-called Kikuchi bands, i.e. pairs of parallel lines. Their detection strongly...
We address the problem of jointly optimizing linear transmit and receive filters for a multi-user MIMO system, under the assumption that all users have individual Minimum-Mean-Square-Error (MMSE) requirements. Each user can perform spatial multiplexing with several data streams (layers). All users and layers are coupled by interference, so the choice of filters is intricately interwoven with the power...
The problem of multiuser scheduling and beamforming with partial channel state information at the transmitter (CSIT) is considered here in the particular context of opportunistic beamforming. We consider a random multiuser beamforming scheme and show how long-term statistical information of users' channels can be efficiently combined with short-term SINR feedback to increase system performance substantially...
A very concise comparison technique for objective image quality assessment is described. The method is based on a angular edge coeherence measure defined by local image expansion into a set of harmonic angular functions. Using the angular edge coherence it is possible to estimate the relative quality of a reproduced image with respect to the original one comparing only the values of a single statistical...
This paper introduces one of the image transform methods using M-channel paraunitary filterbanks (PUFBs) based on Householder matirx. First, redundant parameters of PUFB are eliminated by using the fact that they can be factorized into Givens rotation matices. Next, we propose an eliminating redundant parameters method based on Householder matrix using relationship between Givens rotation and Householder...
H.264/MPEG-4 AVC is the latest video-coding standard jointly developed by VCEG (Video Coding Experts Group of ITU-T and MPEG (Moving Picture Experts Group) of ISO/IEC. It uses state of the art video signals algorithms providing enhanced efficiency if compared with previous standards.
Transformed codebooks are often obtained by a transformation of a codebook, potentially optimum for a particular set of statistical conditions, to best match the statistical environment at hand. The procedure, though suboptimal, has recently been suggested for feedback MISO systems because of their simplicity and effectiveness. We first consider in this paper the analysis of a general vector quantizer...
Spatial transforms and fuzzy pattern classification with unimodal potential functions are established in signal processing. They have proved to be excellent tools in feature extraction and classification. In this paper we present a concept on an image processing and classification scheme for a print-to-edge registration application. The application describes the position detection of objects in banknotes...
In the field of computer vision, specifically for applications aiming at the accurate 3D reconstruction of either natural or hand-made objects, only a few methods are able to recover the shape of transparent objects. Among these, polarimetric imagery has already proved its ability to deal with such objects. In this paper, after a short presentation of the theoretical background leading to the proposed...
An alternative mechanism for audio masking is postulated. This mechanism is derived as a solution to the classic problem of representing a signal as a linear combination of basis functions which are only approximately orthogonal and hence are prone to leakage. This mechanism involves augmenting each basis function or filter with an auxiliary filter. In this combined detection/estimation process the...
The second-order blind identification (SOBI) algorithm for separation of stationary sources was proved to be useful in many biomedical applications. This paper revisits the weights-adjusted variant of SOBI, known as WASOBI, which is asymptotically optimal (in separating Gaussian parametric processes), yet prohibitively computationally demanding for more than 2–3 sources. A computationally feasible...
Audio compression has progressively gained higher importance in the Internet thanks to massive amount of multimedia services on it. This new services require coders adapted to that new environment. Therefore, new generation coders use more complex models focused on features which make possible its use for audio streaming over the Internet, mainly low bit rate, scalability and robustness. In our case,...
In mobile multiple-access communications, not only the location of active users, but also their number varies with time. In typical analyses, multiuser detection theory has been developed under the assumption that the number of active users is constant and known at the receiver, and coincides with the maximum number of users entitled to access the system. This assumption is often overly pessimistic,...
Antique photographic prints are subject to fading due to the action of time and of diverse chemical agents. A method for automated virtual restoration of digital images obtained from scanned photographic prints is proposed in this paper. The effects of film grain noise are also taken into consideration. Experimental results on archive photographic material show the performances of the proposed technique.
A Sensor node localization algorithm for indoor quasi-static sensor environments using spatial domain quasi-maximum likelihood (QML) estimation is presented. A time of arrival (TOA) based algorithm is used to arrive at the “pseudo” range estimates from the base stations to the sensor nodes. The localization algorithm uses spatial domain quasi-maximum likelihood estimation to determine the actual sensor...
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