Electrical and Electronics

Edge truncated slot Aperture microstrip patch antenna for dual frequency operation is investigated in this paper. A simple microstrip edge fed has been used to feed the antenna and a quarter wave length transformers is used for impedance matching. The size of the antenna is reduced by 25.4% when compare to conventional square patch antenna. Design concepts with feeding methods are given along with simulated results. The antenna is showing a gain of 5.9db and a return loss of less than -10dB with VSWR<2 at both resonating frequencies.

This paper presents a multiple description coding method for HD image. The proposed method is bases on the SPIHT algorithm which provides high image compression ratio. The algorithm based on wavelet transforms and Wavelet-based compression provides multi-resolution hierarchical characteristics. This proposed method also uses poly phase sampling technique to generate multiple descriptions. The technique reduces the transmission error and memory required for storing HD images. The proposed method proved higher performances in terms of PSNR when compared to the standard SPIHT. The graph of PSNR versus BER is given in the experimental results.

Over the last three decades of the 20th century, gross domestic product per capita, exponential growth in mobile technology and population growth were the main drivers of increases in global warming and climate change. Industrial revolution and electronics, information and communication technology products have altered the landscape of modern society in countless ways, in office, at home and on mobility. However, they have created and added a new source of heat generation and emission into environment due to consumer electronics products. In spite of recent studies indicating possible threats to global climate, there is no long term data available on the amount of heat generated, emitted and dissipated into environment by cell phones. The aim of this research work is to experimentally measure the heat generated by cell phones during on(sleep/Idle) mode, Rx and Tx modes. The experiments were conducted using specially fabricated four decimal digit temperature measurement test instrument. Population and cell phones projections for India, China, USA and the whole world were also included in this research work for 2050. An attempt is made to indicate amount of heat generated, emitted and dissipated into environment by India, China, USA and entire world by cellular mobiles at present and projections for 2050.

A new model of fractal geometry for microstrip patch antenna is presented in this paper. The current fractal structure is implemented on patch aperture by placing slots in a systematic order. A commercial substrate material of RT-duroid is chosen with dielectric constant of 2.2 and loss tangent of 0.009. The dimension of the patch aperture is 56.7X42.9 mm. The simulated results show that the antenna is resonating at 2.6 GHz and 2.8 GHz, which comes under Wi-Fi application and a very good performance, is observed with respect to impedance bandwidth return loss, field distributions and radiation pattern.

Array patterns depends on type of elements, spacing between the elements and length of the array etc., conventionally elements are spaced at ?/2 in an array. However, in this paper we are made to generate the normalized radiation patterns for different spacing and different types of elements. It has been possible to control the radiation pattern by controlling the spacing between the elements. The arrays considered contain non-identical elements with non-uniform spacing. The results are useful for design of arrays to produce low side lobes for EMI suppression.

This paper investigtaes a comparative evaluation of carrier-based pulsewidth modulation (CB-PWM) methods devoted to the control of a B3-VSI, also known delta inverter, feeding an open-loop induction motor (IM) drives. Four CB-PWM methods namely: (i) sinusoidal PWM (SPWM), (ii) third-harmonic injection PWM (THI-PWM), (iii) optimal PWM (OPT-PWM), and (iv) space-vector PWM (SV-PWM) are analytically presented in order to control a delta inverter. The performance of the CB-PWM methods under consideration are firstly presented and therefore their control performances are analyzed and compared based on simulation and experimental results. The comparison is achieved by an investigation of the total and partial harmonic distortion ratios of the IM stator phase currents.

This research paper portrays the automatic energy management system. Solar energy is used as alternate renewable energy and the energy obtained from solar energy can be directly utilized as dc supply for handling dc machines. The DC power is further converted to AC with the help of inverter. This process takes place automatically with the help of advanced microcontroller. The microcontroller is programmed in such a way to detect the kind of power supply needed for machines (i.e.) whether AC or DC supply. If there is no need of power supply to the machines solar energy can be directly stored in the battery for later use. This technique is applicable for both in residential and industries purpose. For the implementation of the system PIC microcontroller is used and simulation is done by Keil C µ Vision 4 software is applied for different mode of operations. In order to reduce the bus bars and wastage of power, this system provides a solution to operate efficiently into different modes. The result of our research idea will be done in Keil C software.

In this paper we propose a new approach of processing speech signal which is degraded by the reverberant components. This method is based on the analysis of short [2ms] segment of data to enhance the region of the speech signal and analyzing the speech components without degradation due to reverberation, using various methods [FFT, DCT& DWT] and comparison of their results.

In the field of simulation work, it could proceed to an extent that, simulate with arbitrary values of the passive component and the voltage sources. The simulation results recorded various strategic points in the circuit indicate and validate the fact that the circuit is working in the expected lines with regard to the energy transfer in the expected lines with regard to the energy transfer in the tank circuit and sustenance in DC transient Analysis. Also in this proposed experimental work, it is observed that for an arbitrary load, the voltage obtained is agreeing with the theoretically computed DC-Voltage levels. The scope of the work can be extended to the actual calculation of the passives, the initial voltages across the capacitors and inductors. In addition to the exciting DC levels of the sources employed. The small signal analysis can also be done with due regard to the desired behavioural properties of switching devices used.

Transmission line protection is an important issue in power system engineering because 85 to 87% of power system faults are occurring in transmission lines. This paper presents a novel technique to detect and classify the different operating conditions in high voltage transmission lines to contribute quick and reliable operation of protection schemes. Discrimination among different operating conditions of transmission lines is achieved by combining wavelet transforms with support vector machine. MATLAB(7.3) / Simulink is used to simulate different operating conditions in high voltage transmission lines. The fault conditions considered are single phase to ground fault, line to line fault, double line to ground fault and three phase short circuit conditions. The circuit breaker operation and capacitor switching are the non-fault operating conditions. The discrete wavelet transforsms (DWT) are applied for analysis of simulated three phase current signals, because of its ability to extract information from the transient signal, simultaneously both in time and frequency domain. The wavelet family chosen is Daubechies, filter used – DB2, resolution level -3.The data sets which are obtained from the DWT are used for training and testing the support vector machine (SVM). In this proposed scheme SVM is used as classifier. It has the ability to detect and classify the given operating condition whether it is a fault or non-fault operating condition. It is concluded that this scheme discriminates the six different operating conditions considered in a very clear manner.