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In this paper we present a frame by frame steganalysis scheme for digital video sequences based on average filtering of frame. The goal of steganalysis is to detect and/or estimate potentially hidden information from observed data with little or no knowledge about steganography algorithm and/or its parameters. Our blind scheme is successful in detecting hidden information of antipodal nature.
In this paper, we present an approach to estimate fractal complexity of discrete time signal waveforms based on computation of area bounded by sample points of the signal at different time resolutions. The slope of best straight line fit to the graph of log(Ark/ rk2) versus log(1/rk) is estimated, where Ark is the area computed at different time resolutions and rk time resolutions at which the area...
Based on the modeling frequency hopping spread spectrum signal it can be shown that parametric methods of line spectral analysis is well suited for detection and estimation of low probability of intercept frequency hopping signals if the issues of order and time localization are resolved. The detection and estimation problem becomes more complex if frequency hopping is adaptive in nature. An algorithm...
Orthogonal Frequency Division Multiple Access (OFDMA) gains increasing attention for broadband, high data rate fixed/mobile communications. As the basic modulation technique in OFDMA is orthogonal frequency division multiplexing (OFDM), it is severely affected by carrier frequency offset (CFO). The CFO causes loss of orthogonality among the subcarriers. In this paper, we propose a method for joint...
In this work, we have studied the effectiveness of recently proposed warp factor estimation method based on correlation between the pitch frequency and the warp factor for speaker normalization. Our study shows that estimation of warp factors using maximum a posteriori criterion by exploiting the statistics from the pitch based warp factor estimation approach results in 12.5% relative improvement...
This paper represents the estimation of frequency which is an important power system parameter by several variant of recursive techniques. Estimation of frequency is not new as found in the literature such as Discrete Fourier Transformation, Least Mean Square Technique etc. In this paper we have implemented Recursive least square (RLS) and Extended Least square (ELS) for estimation of frequency. These...
Signal to noise ratio (SNR) estimation is an important problem in many communication systems. SNR often needs to be estimated in the presence of unknown transmitted data symbols in a non data aided (NDA) manner. In this paper we derive a methodology to calculate the Cramer-Rao lower bound (CRLB) of NDA SNR estimation in an additive white Gaussian noise (AWGN) channel for any symmetric constellation...
Non-stationary signal modeling is a well addressed problem in the literature. Many methods have been proposed to model non-stationary signals such as time varying linear prediction and AM-FM modeling, the later being more popular. Estimation techniques to determine the AM-FM components of narrow-band signal, such as Hilbert transform, DESA1, DESA2, auditory processing approach, ZC approach, etc.,...
This paper presents a new subspace-based direction of arrival (DOA) estimation method based on the concept of well known propagator method (PM) and its noise subspace being invariant to power of the sources. With the objective of increasing the resolution, this paper introduces a new matrix on which partitioning is done and PM is employed. The proposed method has higher resolution capabilities than...
Adequate grasping force estimation and slip detection is a vital problem in wider applications of robots and manipulators in industries as well as in our everyday life. In this paper, a new methodology for slip detection during grasping by robot grippers/end-effectors using tactile sensor has been presented. During the object slippage, the tactile sensor in touch with the object surface travels along...
A variable step size (VSS) learning rate control algorithm based on echo leakage factor is proposed for controlling the adaptation of time-domain ldquocircular leaky normalized least-mean squarerdquo (CLNLMS) algorithm used in acoustic echo cancellation (AEC). The proposed control algorithm provides higher step size during initial convergence to speedup the convergence rate and reduces the step size...
The present study proposes two alternate model structures to represent exponentially damped sinusoids and proposes a novel method of estimating the parameters of the damped sinusoids by combining Hankel singular value decomposition (HSVD) with the extended complex Kalman filter (ECKF). The ECKF is capable of estimating the parameters and can effectively track the variations of damping constants and...
Coherent detection techniques require the channel information for the symbol detection and such techniques are reported to have better performance than the non coherent ones. Method of Least Squares (LS) is a popular technique for performing channel estimation. The LS Estimation method requires the channel to be constant through out the estimation period. In reality, the wireless channel is time varying...
Heterogeneous cluster is a reasonable extension of conventional PC clusters, while it is a difficult target for optimization. Although load imbalance can be alleviated by invoking multiple processes on fast nodes (without modification of source code), the optimal process allocation is not obvious. The preceding studies reported that practical estimation is possible by constructing the execution-time...
Ultra-Wideband (UWB) communication system provides high accurate localization due to the high multi-path resolution capacity. For Ultra-Wideband (UWB) Localization systems, time-based schemes namely Time of Arrival (TOA) and Time Difference of Arrival (TDOA) provide very good accuracy due to the high time resolution (large bandwidth) of UWB signals. Due to the inherent suitability and accuracy of...
In distributed multisensor fusion, local estimates may have to be communicated to a distant central processor. Hence, the communication channel noise is an important factor to the fusion algorithm. Optimal linear methods can be applied when channel noise is supposed to be Gaussian. In practice, the channel noise is not Gaussian and usually modeled by a contaminated Gaussian distribution. A two-stage...
Motion estimation and compensation is the most computationally complex module of video coder. In this paper, an innovative algorithm is proposed for a further complexity reduction of the motion estimation (ME) module of video coder by employing motion detection prior to motion compensation. A dynamic motion detection (DMD) module can be added to the video coder in order to decide whether the current...
In this paper, we address the estimation of carrier frequency offset (CFO) in orthogonal frequency division multiplexing (OFDM) based multiple input multiple output (MIMO) communication systems. One of the novelties of the proposed approach is the judicious combination of two methods so as to reduce the bandwidth overhead and computational complexity without compromising the CFO estimation range....
The directional protection of bus-bars using time-frequency transform such as S-transform is presented in the paper. S-transform is used to estimates the phase and amplitude of the fault current signals during fault situations. The difference in phase angle between positive sequence component of the current during fault and pre-fault conditions distinguishes internal faults (bus-bar faults) from external...
Sparse multi-path channels (MPC) are often encountered in several wireless communications. Exploiting the sparse property of MPC, several estimation methods have been proposed in recent years. Unlike the previous methods based on either dense MPC or sparse MPC models, we propose a novel MPC estimation method based on a generalized hybrid MPC model. The existed least squares (LS) and sparse component...
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