Electrical and Electronics

In this paper, a three layer Small single feed multiband microstrip antenna loaded with slit and two perpendicular shorting posts, is presented. Wide band frequency of operation demonstrated by single geometry, for broadening the bandwidth gap-coupled multi-resonator loaded on the patch, the simulation of proposed design antenna has done by MOM IE3DTM Simulator. The geometry of a single probe fed rectangular microstrip antenna has textured by slit loading and two orthogonal shorting pin on the top layer patch. We have also textured the size of the antenna. This proposed antenna is used for GSM, satellite and wireless communication in, L Band. Achieved 63% reduction of geometrical area of the antenna for L –Band, achieved 57% -10dB impedance bandwidth of L Band.

A dual-band characteristic of multilayer aperture coupled microstrip log-periodic dipole antenna is studied. Further loading of patches is performed and its effects are investigated. It is a probe fed antenna for impedance matching with 50? coaxial cable. This antenna works well in the frequency range 4.3 GHz to 8.5 GHz. It is basically a low cost, light weight medium gain antenna, which is used for wireless communication. The multilayer microstrip antenna structure involves addition of multiple layers one over the other. When a microstrip antenna is stacked with a superstrate dielectric layer, its properties like resonance frequency, gain and bandwidth are changed, which may affect the system performance. With proper choice of the thickness of substrate and superstrate layers, significant increase in bandwidth and return loss can be achieved for practical applications. This structure uses stacked configuration of three different substrates. One dielectric substrate as a feeding plane, one dielectric substrate as aperture plane and a dielectric substrate as a LPDA. The simulated antenna yields -29.16 dB return loss with 33% bandwidth with a size of 24x26x6mm3. The proposed antennas present an excellent candidate for compact and low-cost microwave integrated systems.

A Broadband multilayer antenna for C-Band applications is presented in this paper. The proposed antenna is composed of a FR-4 and air gap Dielectric material, two square slots, two L-Slot, and a Radom. By introducing the two parts, the impedance bandwidth of the antenna can be significantly enhanced. Analysis done with and without ground plane. Simulation results show that the proposed antenna can operate from 3.2GHz to 4.8 GHz with low VSWRs ? 2. Stable antenna gain (dB) is also achieved over the entire operating frequency band. Furthermore, the size of the proposed antenna is very compact, which is only at the centre of the operating frequency band.

Here, a equilateral triangular shaped circular feed network is designed. This circular feed network can radiate in eight different directions. This radiation is depending on four inputs ports which are excited. It can cover wide area within upper hemisphere. This antenna is designed in such a way that it is useful for any applicable GHz ISM band frequency and utilizes a suspended FR4 substrate. For this antenna we used positive microstrip elements, so that it will make easy to manufacture.

This paper describes the sensor nodes and its hardware constraints. This paper throws light over the energy issues of the sensor nodes while transmitting and receiving data over the distances and effects of attenuation due to several environmental parameters. This paper also gives the comparative analysis of received power at different heights of transmitter antenna.

The power dissipation in a system-level attributes to buses is increasing in VLSI circuits. Therefore reduce of power consumption in switching activity at the I/O ports can save significant save of power. Change of voltage level on the wires significant power consumptions. As the technology scaled down, the increased wire aspect ratio (height/width) reduce the spacing between individual bus wires. This resulted in the domination of coupling capacitance. There are so many techniques have been proposed to reduce the coupling activity along with the self-switching activity. Initially, Bus invert method can be applied to encode buses without prior knowledge of data statistics. Another encoding technique called “Sequence Switch Coding for low-power data transmission” (SSC) was proposed by Myungchul Yoon to minimize Self Transition activity in buses. Among the Bus Invert method and Sequence Switch Coding, the Bus Invert method has gained popularity because of its better energy reduction (upto25.45%). However, both Bus Inver and SSC bus encoding techniques reduce only self transitions and do not consider the effect of coupling transitions. Therefore, it is important to minimize the power dissipation and cross talk delay by minimizing the both self transitions and coupling transitions on bus for the fast and safe VLSI circuits. A new technique isintroduced by doing some modifications to existing SSC technique given by Myungchul Yoon et.al, to reduce the energy dissipation and delay on DSM bus through encoding the data on the bus.

The four quadrant analog multiplier proposed by Rathor and Bhattacharya is reanalysed and modified in a different way for simple and low cost multiplication applications without using any reference waveforms. Verification of the feasibility of the circuit configuration is established by way of test results.

This paper proposes a review of the main uniqueness and parameters of photovoltaic (PV) cell. A photovoltaic (PV) cell converts the solar energy into the electrical energy by the photovoltaic effect. The heat does not participate constructively in this process. Heat actually limits the performance of p-n layers, and the presence of excess heat is a sign of deterioration in a PV cell. Most solar cells are built from silicon, and the presence of impurities influences their performance. The losses occurring in the field operation of a PV cell have to be considered in order to calculate precisely its real electric power output. The PV module model is simulated using Matlab. The reviewed model is based on previous studies and previous models. Finally, the model has been compared with experimental data of a commercial PV module USP5-6V.

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.

Increasing need for energy and limited fossil resources, increasing environmental pollution resulting from the burning of these resources, the effects of global warming and the greenhouse effects, acid rain and the need to balance the propagation of CO2, all call for the necessity of saving fossil resources and increased attention to the use of renewable energy sources. Wind energy is one of the main types of renewable energies that have always attracted the human mind so that man is always thinking of using this energy in the industry. The human had been used wind to move boats and sailing ships and windmills. In the current situation with regard to the above mentioned terms and economic justification of wind energy compared to other energy sources, wind energy seems to be vital and essential. This article firstly provides an introduction to the field installation locations of wind turbines in the power system and then various methods for predicting wind speed and power of wind farms are expressed. After that Modeling of wind powerhouses are explained. Finally, wind powerhouse modeling methods are fully described and the equations of each model are given.