This paper is concerned with the distributed fusion Kalman filtering problem for networked systems with communication constraints. A dimensionality reduction strategy and a uniform quantization strategy are introduced to reduce communication traffic. To overcome the unboundedness of estimates/measurements in unstable systems, it is proposed to quantize the innovations that are sent to the fusion center

Entropy has been widely applied in system identification in the last decade. In this paper, a novel stochastic gradient algorithm based on minimum Shannon entropy is proposed. Though needing less computation than the mean square error algorithm, the traditional stochastic gradient algorithm converges relatively slowly. To make the convergence faster, a multi-error method and a forgetting factor are

In adaptive filters, variable step-size-based algorithms have demonstrated better performance than conventional least mean square (LMS) and normalized LMS (NLMS) algorithms in terms of convergence speed, mean square error (MSE), and signal-to-noise ratio (SNR) improvement. Recently, adaptive filters have been recommended to be implemented on field programmable gate array (FPGA) devices due to their

Signal modeling is an important technique in many engineering applications. This paper is concerned about signal modeling problem for the sine multi-frequency signals or periodic signals. In terms of different characteristics between the signal output and the signal parameters, a separable modeling scheme is presented for estimating the signal parameters. In order to seize the real-time information

This paper aims to propose an effective steerable directional Laplacian regularizer for image denoising. A steerable inhomogeneous directional Laplacian associated with an efficient contextual indicator is presented and taken as the diffusion flux to formulate the desired steerable directional Laplacian regularizer. With the contextual indicator for contextual discontinuities, the steerable directional

An optimized color image watermarking algorithm with stationary wavelet transform and singular value decomposition has been proposed in this work. The algorithm uses two watermarks to address the issues of copyright protection and tamper localization. A gray-scale image watermark is embedded in the transform domain of the green plane of the cover image to address the issue of copyright protection.

Approximate computing is a striking approach to design area-efficient low-power datapath units for fault buoyant applications. This brief presents the design of a novel 4: 2 approximate compressor that generates no error in the carry signal. The proposed compressor is employed for partial product (PP) compression in two variants of Dadda multiplier to see its effectiveness in error-resilient image

\(\varDelta \varSigma \) analog-to-digital converters (ADCs) are largely used in sensor acquisition applications. In the last few years, standalone \(\varDelta \varSigma \) modulators have become increasingly available as off-the-shelf parts. To build a complete ADC, a standalone modulator has to be paired with some advanced elaboration unit, such as a field programmable gate array (FPGA) or a digital

We address the problem of signal denoising and pattern recognition in processing batch-mode time-series data by combining linear time-invariant filters, orthogonal multiresolution representations, and sparsity-based methods. We propose a novel approach to designing higher-order zero-phase low-pass, high-pass, and band-pass infinite impulse response filters as matrices, using spectral transformation

A method for assigning characteristic functions on rational functions is presented herein. In systems with rational characteristic loci, input–output decoupling and commutative compensator design are possible. In this method, unlike previous research, which used the approximation method in a specific frequency range, a perturbation is created in the transfer function such that a new transfer function

In this paper, a new array configuration termed as Spread Orthogonal Loop and Dipole (SOLD) array is presented for estimating direction and polarization parameters of multiple incident signals. In the SOLD array configuration, the spacings of any two adjacent SOLD antennas are set to be mutual primes with respect to a half-wavelength. Moreover, the loop is separated far away from the dipole within

This paper introduces a simulated grounded inductor (SGI) circuit realization based on two terminal active devices, namely negative impedance converters. The proposed SGI contains a minimum number of passive components when compared to its two terminal active device-based realization counterparts in the literature. It includes a grounded capacitor that is an advantage in integrated circuit process

In this paper, we propose a novel low-complexity scheme to extract cyclic features of wideband signals from sub-Nyquist samples as Nyquist rates push contemporary analog-to-digital converters to their performance limits. Due to the sparse spectrum occupancy in wideband, sub-Nyquist sampling is performed and cyclostationary feature extraction is achieved at baseband to identify the modulation scheme

This paper proposes a new approach to investigate the problem of designing sampled-data controller for master–slave synchronization of chaotic Lur’e systems with time delay. Compared with existing methods, this method can make full use of the information of actual sampling pattern. To reflect more realistic the information on both the intervals e(t) to \(e(t_{k})\) and e(t) to \(e(t_{k+1})\), a novel

Watermarking of digital images is a well-known technique that is widely used for securing image contents. A successful watermarking method must be accurate, reversible, resilient, and robust against various attacks. In this paper, we propose a reversible and robust color image watermarking method. A new set of multi-channel fractional-order polar harmonic transforms and their geometric invariants have

The problem of 3D digital object invariability is encountered in image processing, especially in pattern classification/recognition. The 3D object should be correctly recognized regardless of its particular position and orientation in the scene. This paper proposes a new method to extract 3D Charlier moment invariants to translation and scaling (3DCMITS). These descriptors are extracted directly from

The finite-rate-of-innovation (FRI) sampling frame has drawn a great deal of attention in many applications. In this paper, a novel sub-Nyquist FRI-based sampling and reconstruction method in linear canonical transform (LCT) domain is proposed. First, a new, compact-support sampling kernel is designed to acquire sub-Nyquist samples in time domain, which can be viewed as anti-aliasing prefilter in LCT

Direction of arrival (DOA) estimation has paramount importance in array signal processing tasks. A practical issue regarding DOA estimation is the uncertainty in gain/phase of some of the sensor elements. In this paper, we focus on the 2-dimensional DOA (2D-DOA) estimation in the presence of gain/phase uncertainty. We propose a grid-based modeling for the 2D-DOA estimation of the uniform rectangular

Direct acoustic feature-based speaking rate estimation is useful in applications including pronunciation assessment, dysarthria detection and automatic speech recognition. Most of the existing works on speaking rate estimation have steps which are heuristically designed. In contrast to the existing works, in this work a data-driven approach with convolutional neural network-bidirectional long short-term

This paper proposes a novel method of image enhancement via energy curve equalization (ECE). Histogram equalization (HE) appears to be the most straightforward method for image contrast enhancement. Many modifications are already recommended to overcome the confines of HE. The computation of the histogram does not consider the spatial correlations among the surrounding pixels. The current method utilizes

This paper presents a modified minimal realization technique to reduce single input single output (SISO) systems from higher-order SISO systems. The reduction process is based on restructuring the Hankel matrix, which consists of two major elements, i.e., Time Moments and Markov parameters. The system transformation is executed to reduce the order of the system by maintaining the desired system properties

In this paper, speech enhancement is carried out using a modified nonlocal means adaptive filter, and an FPGA prototype is proposed for its implementation. Nonlocal means (NLM) adaptive filtering has been a widely used approach for denoising image and electrocardiogram signals. The temporal and spectral characteristics of the speech signal vary with time. Consequently, NLM filtering is ineffective

This paper presents an improved 8 × 8-bit Booth multiplier with reduced power, delay and area. The major operations that consume power and are responsible for larger critical path delays in Booth multiplication are partial product array generation (PPAG), partial product array compression (PPAC) and partial product array addition (PPAA), for the generation of the final product. So, in our proposed

The implementation of reverse converter is one of the most important elements influencing the performance of a residue number system. In this research, we propose an efficient high-speed and low-area reverse converter for moduli set \(\{ 2^{4n} ,2^{2n} + 1,2^{n} + 1,2^{n} - 1\}\). Due to the form of the moduli set, we have implemented the proposed reverse converter using Chinese remainder theorem and

This paper presents an implementation of a reconfigurable digital down converter (DDC) that can translate high sample rate to lower sample rate signal on field-programmable gate array (FPGA) platform using polyphase filtering. The proposed DDC consists of a polyphase mixer, a cascaded integrator comb (CIC) filter, and a finite impulse response (FIR) filter. The polyphase mixer reduces computational

This paper proposes a new sequence-based approach to resolve the stability problems found in switched systems with unstable subsystems. In existing approaches, the sequence information of switching subsystems is seldom exploited. By exploiting the sequence information, threshold values can be less restrictive and more appropriate for the situation. We study two cases in this paper: (a) all subsystems

Sound field reconstruction technology is used to provide accurate primary reference signals for active noise control systems by reconstructing the interior sound field. Traditionally, time-domain noise signal-based reconstruction modeling has certain deficiencies, such as large data volume, noise reconstruction model complexity and considerable time consumption. Hence, a novel Signal compression optimisation-based

In this paper, we discuss the problem of model order reduction for positive real systems based on balancing methods. The mixed gramian balanced truncation (MGBT) method, which is a modification of the positive real balanced truncation (PRBT) method, focuses on solving one Lyapunov equation and one Riccati equation resulting in less computational effort compared to PRBT requiring solving two Riccati

Approximate computing is gaining grip as a computing paradigm for computer vision, data analytics, and image/signal processing applications. In the era of real-time applications, approximate computing plays a significant role. In many computers including digital signal processors (DSP) and a microprocessor, adders are the main element for the implementation of signal processing applications and digital

Sinusoidal model and chirp model are the two fundamental models in digital signal processing. Recently, a chirp-like model was introduced by Grover et al. (International conference on computing, power and communication technologies, IEEE, pp. 1095–1100, 2018). A chirp-like model is a generalization of a sinusoidal model and provides an alternative to a chirp model. We derive, in this paper, the asymptotic

An on-chip nanopower RC relaxation oscillator is developed in a 180-nm standard CMOS process, consuming 300 nW while running at 10 kHz. Employing a frequency compensation scheme that reduces the frequency drift introduced by comparator offset and delay, the proposed oscillator achieves a significant low temperature coefficient. Furthermore, a supply regulation structure is used to reduce the frequency

Speech emotional content estimation is still a challenge for building robust human–machine interaction systems. Accuracy of emotion estimation depends upon the corpus used for training and the acoustic features employed for modelling the speech signal. Generally, emotion estimation is computationally expensive, and hence, there is a need of developing alternative techniques. In this paper, a low complexity

In this work, we propose a 2\(^7\)-1, 20-Gb/s, low-power, charge-steering, half-rate pseudorandom bit sequence (PRBS) generator in 1.2 V, 65 nm CMOS. At the target data rate, the proposed charge-steering implementation has the lowest power consumption of 0.2 mW/Gb/s compared to the current-mode PRBS generator implementations, thanks to the discrete nature of the charge-steering latch circuit topology

In this paper, we propose a low-complexity and high-speed VLSI architecture design methodology for complex square root computation using COordinate Rotation DIgital Computer (CORDIC). The proposed methodology is independent of angle computation in the CORDIC unlike the state-of-the-art methodologies. The proposed methodology is modelled in VHDL and synthesized under the TSMC 45-nm CMOS technology @

The fractional Fourier transform (FrFT) is a generalization of the usual Fourier transform. The aim of this paper is to show the compression of sound signal in FrFT domain and to prove the qualitative and quantitative uncertainty principles for the FrFT. The first of these results consists the Hardy’s and an \(L^p-L^q\) version of Miyachi’s theorems for the FrFT, which estimates of decay of two fractional

Many classic chirp signal processing algorithms may show significant performance degradation when the signal-to-noise ratio (SNR) is low. To address this problem, this paper proposes a pre-filtering method in time-domain based on deep learning. Different from traditional signal filtering methods, the proposed denoising convolutional neural network (DCNN) is trained to recover the pure signal from the

This article presents a high-performance hybrid full adder (HPHFA) designed with static CMOS logic and pass transistor logic to achieve better power delay product (PDP). The circuit was implemented using cadence virtuoso tool on gpdk 90 nm and 45 nm CMOS process technologies. Further, the structure has been extended to 32 bits to test the performance of HPHFA in higher-order circuitry. The proposed

A required step to realize blind source separation of a signal is to determine the number of sources building up the mixture. Generally, the assumption of equal number of sources and mixtures is imposed which becomes invalid in single-channel mixtures. Therefore, in order to apply conventional solutions, a single-channel mixture signal can be converted into a pseudo-multi-channel signal. The empirical

We consider the design of constant-modulus waveforms for wideband multiple-input multiple-output radar. The aim is to match a desired transmit beampattern. To tackle the non-convex design problem, we develop an iterative algorithm, which is based on cyclic optimization and majorization–minimization. We prove that the sequence of the objective values of the proposed algorithm has guaranteed convergence

In recent years, reversible circuits have attracted the attention of many researchers. Their applications include the design of low-power digital circuits, the design of computational circuits in quantum computers and DNA-based calculations. In this paper, an effective 5 × 5 reversible block, called new block (NB), is first proposed, and then, using the proposed reversible block, a novel reversible

A new source coding is proposed for secure and robust speech communications. The method is based on the combination of compressed sensing and split-multistage vector quantization. The proposed codec is integrated in an end-to-end communication system, and its performance is investigated in real mobile communication conditions. Channel compensation techniques are considered to mitigate the Rayleigh

In this paper, an analytical model of a closed-loop frequency-locked loop (FLL) based on a two-stage voltage-controlled oscillator (VCO) is proposed. Switch capacitor technology is used to accelerate the conversion speed of the frequency-to-voltage converter for reducing the locking time. The VCO is reduced to the minimum two-stage delay ring structure for outputting high-frequency signals with less

The problem of global asymptotic stability (GAS) of two-dimensional (2-D) digital filters based on the Fornasini-Marchesini second local state-space (FMSLSS) model with saturation arithmetic is studied in this paper. A novel GAS criterion for the 2-D digital filter is presented. The obtained criterion is compared with several previously reported criteria.

A 160 MHz bandwidth 90° active RC–CR phase shifter with integrated on-line amplitude locked loop (ALL) calibration targeted to 802.11ac 5 GHz wireless local area network (WLAN) applications is presented in this paper. The quadrature phase shifter is a key component for transceivers employing the Hartley image rejection architecture. The passive RC–CR phase shifter generates the required two quadrature

The irrational coefficients of orthogonal wavelet filters require a large amount of hardware for their implementation. This results in huge memory requirement, increased power dissipation and reduction in speed of operation. This paper presents a new class of multiplier free db3 orthogonal wavelet filter bank with significantly reduced power dissipation, adders and shifters. In this paper, dyadic filter

This paper studies commutativity of sixth-order differential systems with zero and nonzero initial conditions (ICs). Given a sixth-order differential system \(A\), we find its commutative pair, that is a new differential system \(B\) of order \(m \le 6\); the obtained result will be used to show the input–output equivalency between the cascaded-connected systems \(AB\) and \(BA\). Necessary and sufficient

Research and development of speech technology applications in low-resource languages (LRL) are challenging due to the non-availability of proper speech corpus. Especially, for most of the Indian languages, the amount and type of data found in different digital sources are sparse and prior works are too few to serve the purpose of large-scale development needs. This paper illustrates the creation process

This paper investigates observer design for a class of one-sided Lipschitz descriptor systems with time-varying delay and uncertain parameters. In order to provide a general framework for large-scale systems, the paper considers uncertainties, nonlinearities, disturbance and time-varying delay at both output and state. By constructing Lyapunov–Krasovskii functional, and using the one-sided Lipschitz

Motion artifact is widely present in exercise electrocardiogram (ECG) signal, which is an important factor affecting the accuracy of QRS complex detection. A simple-fast QRS detection algorithm based on energy segmentation is proposed, which is suitable for exercise ECG measured by the wearable monitoring device. The proposed method mainly consists of four parts: the 15–25 Hz band-pass filter, the

Under the framework of compressed sensing theory, the greedy algorithm achieves good reconstruction performance with known signal sparsity. However, unknown sparsity of sparse signals in practical applications brings obstacles for signal reconstruction. Specifically, the conventional sparsity adaptive adjustment algorithm takes long time to finish the reconstruction, and the accuracy of reconstruction

The i-vector/probabilistic linear discriminant analysis (PLDA) framework has been popularly used in the field of speaker verification for a long time. Lately, the introduction of online i-vectors and its integration with dynamic time warping template matching technique have significantly improved the performance of text-dependent speaker verification system. The PLDA model learns to discriminate among

In this paper, the design problem of fault detection filter for a class of networked control system subject to Markov jump parameters, randomly occurring uncertainties, sensor faults and packet dropouts by using state feedback control is investigated. The fault detection filter is used as an optimal residual generator that generates the residual signal and also guarantees the sensitivity of residual

The forward and inverse DCT has many applications in digital signal processing area, but, due to its high arithmetic complexity, it is necessary to find efficient software implementations or even to find VLSI implementations for them. Existing fast algorithms for IDCT or DCT have a SFG graph that is not very regular and modular and, even more importantly, the topology of the interconnection network

The aim of this paper is to introduce a novel similarity measure using fractional-order derivative for patch comparison in low-rank image denoising approach. Recently, several outstanding low-rank image denoising algorithms have been proposed. However, these methods have limitations in the sense that certain irrelevant patches can be selected during patch comparison. These undesired patches affect

Kernel least mean square (KLMS) algorithm is a popular method for time series online prediction. It has the advantages of good robustness, low computational complexity, model simplicity and online learning ability. Unfortunately, as input data grows, the dictionary size increases and the computational complexity raises significantly. In addition, how to improve the adaptability in time-varying environments

Graph filtering has recently attracted significant attention in signal processing. This study proposes an adaptive graph filtering method with intra-patch pixel smoothing (AWGF-PS) to improve the quality of denoised images. A detailed coefficient shrinkage algorithm is provided for the graph filter, which makes the noisy component in each graph frequency band adaptively shrink with its component significance

Sparse arrays can increase the array aperture and degrees of freedom through the construction of either sum or difference co-arrays or both. In order to exploit the advantages of sparse arrays while estimating directions of arrival (DOAs) of a mixture of circular and non-circular signals, in this paper, a gridless DOA estimation method is proposed by employing a recently introduced enhanced nested

In this work, a new class of stochastic gradient algorithm is developed based on fractional calculus. Unlike the existing algorithms, the concept of complex fractional gradient is introduced by employing Caputo’s fractional derivative which results in a fractional steepest descent algorithm and a fractional-order complex LMS (FoCLMS) algorithm. We demonstrate that with the Caputo’s fractional gradient

A new voltage mode, carbon nanotube field-effect transistor (CNTFET) based multiple input single output active only biquadratic filter (AOBF), is presented. The proposed AOBF employs simple and compact single ended transconductance elements, voltage-controlled resistor (VCR) and varactor. The proposed AOBF provides band-pass filter, band-reject filter, all-pass filter, high-pass filter and low-pass

The finite-time control is considered for reaction–diffusion systems (RDSs) under a designed spatial sampled-data controller (SSDC). Firstly, an SSDC is designed and the finite-time stability is investigated for RDSs, based on the designed controller. In terms on Lyapunov functional method and inequality techniques, a sufficient condition is obtained to ensure the finite-time stability. Then, uncertain