Vinay Kumar Deolia

Abstract: This paper presents a robust sliding mode controller for a class of unknown nonlinear discrete-time systems in the presence of fixed time delay. A neural-network approximation and the Lyapunov-Krasovskii functional theory into the sliding-mode technique is used and a neural-network based sliding mode control scheme is proposed. Because of the novality of Chebyshev Neural Networks (CNNs), that it requires much less computation time as compare to multi layer neural network (MLNN), is preferred to approximate the unknown system functions. By means of linear matrix inequalities, a sufficient condition is derived to ensure the asymptotic stability such that the sliding mode dynamics is restricted to the defined sliding surface. The proposed sliding mode control technique guarantees the system state trajectory to the designed sliding surface. Finally, simulation results illustrate the main characteristics and performance of the proposed approach.

Abstract: In one's day to day life; internet is growing and became an important part. Digital content can easily be downloaded, copied or edited. Digital content can be secured by various ways. Digital Watermarking is one of the methods for the protection of Digital Content. Digital Watermarking is a method by which data can be secured by hiding data in any image which can work as a carrier image. The carrier image is also known as cover image. Watermarking is an interactive method to protect and identify the digital data. It permits various types of watermarks to be hidden in digital data e.g. image, audio and video. In this work, watermarking has been done using LSB technique, DCT transform and DWT transform. These techniques are compared on the basis of peak signal to noise ratio (PSNR) and normalized correlation (NC). Parameters are compared for various noises like Gaussian noise, Poisson noise, Salt and Pepper noise and Speckle noise.

Abstract: Control of flow rate in industrial plants is an essential and crucial task, which is usually achieved by pneumatic control valves in industries. Use of these valves often incorporates nonlinear and uncertain dynamics in the control loop on account of its input-output characteristics, which may result in degradation of control loop performance. To address this concern, a robust and improved fractional order parallel control structure (FOPCS) for flow control is proposed in this paper. The proposed FOPCS is an extension of parallel control structure (PCS) with the help of fractional order calculus, to enhance the robustness in the control loop without compromising with control performance. Also, a global optimization technique, backtracking search algorithm was further employed to critically tune the parameters of control structures. This was done in order to obtain an optimized and enhanced performance from the control loop. Extensive runtime studies on a laboratory scale plant, using advanced data acquisition facilities, were carried out to showcase the effectiveness of developed FOPCS. Proposed FOPCS is thoroughly assessed in terms of servo, regulatory and robustness performance. A quantitative comparison of FOPCS with PCS is also made on the basis of integral of absolute error, integral of absolute rate of controller output and their algebraic summation. All the conducted experimental studies suggested that proposed FOPCS was able to address the issues pertaining to uncertain and nonlinear behaviour of pneumatic control valve in the flow control loop.

Abstract: This paper proposes the adaptive back stepping controller for a class of nonlinear discrete-time systems in strict-feedback form with unknown dead-zone using neural networks. The control design is attained by introducing the dead-zone nonlinearity and using it in the controller design with back stepping technique. A dead-zone inverse is developed to compensate the dead-zone effect in nonlinear systems. In this scheme, Chebyshev Neural Network (CNN) is used to approximate the unknown nonlinear functions and also used to compensate the dead-zone nonlinearity. New weight updates laws are derived to guarantee uniform ultimate boundedness (UUB) for all signals in closed loop system.

Abstract: This paper characterizes a design analysis of low power (LP) and low voltage (LV) optimized low noise amplifier (LNA) for wide band applications. With review discussion on design challenges of LP and LV, a new biasing metric has been introduced for radio frequency analog circuit. The proposed LNA consists of two stages, the first stage is a current reuse topology, in which a combination of PMOS transistor stack on top of NMOS transistor has been used with series inductive peaking in the feed-back loop. It helps a lot to achieve the target of LP and LV, while the second stage is a mutually coupled CS stage, used for wideband matching to enhance the bandwidth and noise figure (NF). For optimization of passive component parameters of proposed LNA, particle swarm optimization (PSO) algorithm has been used. All the simulations have been done for a range of frequency 0–35 GHz in Cadence Virtuoso software 45-nm CMOS technology. The results quoted 18.57 dB maximum voltage gain, 2.4 dB NF, 17.1 dB S11, 16.6 dB S21, at frequency 25.4 GHz with 0.8 V, 1.6 mW broad band LNA.

Abstract: Reactive matching is extended to wide bandwidths using the impedance property of LC-ladder filters. In this paper, we present a systematic method to design wideband low-noise amplifiers. An SiGe amplifier with on-chip matching network spanning 3-10 GHz delivers 21-dB peak gain, 2.5-dB noise figure, and -1-dBm input IP3 at 5 GHz, with a 10-mA bias current.

Abstract: In this paper, an adaptive fuzzy optimal control design is addressed for a class of unknown nonlinear discrete-time systems. The controlled systems are in a strict-feedback frame and contain unknown functions and nonsymmetric dead-zone. For this class of systems, the control objective is to design a controller, which not only guarantees the stability of the systems, but achieves the optimal control performance as well. This immediately brings about the difficulties in the controller design. To this end, the fuzzy logic systems are employed to approximate the unknown functions in the systems. Based on the utility functions and the critic designs, and by applying the backsteppping design technique, a reinforcement learning algorithm is used to develop an optimal control signal. The adaptation auxiliary signal for unknown dead-zone parameters is established to compensate for the effect of nonsymmetric dead-zone on the control performance, and the updating laws are obtained based on the gradient descent rule. The stability of the control systems can be proved based on the difference Lyapunov function method. The feasibility of the proposed control approach is further demonstrated via two simulation examples.

Abstract: In the paper, an adaptive tracking control design is studied for a class of nonlinear discrete-time systems with dead-zone input. The considered systems are of the nonaffine pure-feedback form and the dead-zone input appears nonlinearly in the systems. The contributions of the paper are that: 1) it is for the first time to investigate the control problem for this class of discrete-time systems with dead-zone; 2) there are major difficulties for stabilizing such systems and in order to overcome the difficulties, the systems are transformed into an n -step-ahead predictor but nonaffine function is still existent; and 3) an adaptive compensative term is constructed to compensate for the parameters of the dead-zone. The neural networks are used to approximate the unknown functions in the transformed systems. Based on the Lyapunov theory, it is proven that all the signals in the closed-loop system are semi-globally uniformly ultimately bounded and the tracking error converges to a small neighborhood of zero. Two simulation examples are provided to verify the effectiveness of the control approach in the paper.

Abstract: This expanded and thoroughly revised edition of Thomas H. Lee's acclaimed guide to the design of gigahertz RF integrated circuits features a completely new chapter on the principles of wireless systems. The chapters on low-noise amplifiers, oscillators and phase noise have been significantly expanded as well. The chapter on architectures now contains several examples of complete chip designs that bring together all the various theoretical and practical elements involved in producing a prototype chip. First Edition Hb (1998): 0-521-63061-4 First Edition Pb (1998); 0-521-63922-0