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In the present paper a moderate area programmable memory built-in-self-test (BIST) architecture supporting multiple algorithm loading is proposed. The entire BIST operation is made possible with a cheap low cost tester used for initial loading. The loaded data is decoded and executed by the BIST architecture at high speed since there is no interruption from the tester. This avoids costly high speed interfaces during the execution of the BIST. The proposed BIST architecture can execute all March like algorithms. It supports normal, preset, retention and repair modes of operation. Repair facility is value addition to the proposed design. The proposed programmable BIST architecture is very flexible and cost effective.

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The massive expansion of mobile communications over the recent years has meant that telecommunications companies continually need to increase the capacity and coverage of their networks to keep up with demand . This has required more base station antennas to be erected, resulting in increased costs and visual pollution. Smart antenna systems have gained increased interest as they promise to provide significant increases in system capacity and performance, and greater coverage, meaning less base stations are needed to cover the same area compared to conventional antennas. The increase in demand for fast data transmission rates in today's society leads to greater inter-symbol interference (ISI) in the received signal, due to multipath propagation. Adaptive equalizers can be used to periodically estimate the communication channel and then perform equalization to reduce the effects of ISI. Smart antennas have promised to provide significant increases in system capacity and performance in wireless communication systems[1]. In turn, this leads to increased revenue for the telecommunications companies and also a reduction in dropped and blocked calls. Other benefits include greater coverage, meaning less base stations are needed to cover the same area compared to conventional antennas. For these reasons, smart antennas have gained greater interest over the recent years.

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Grid computing enables transparent access to shared and/or idle computing, storage, and network resources anywhere, anytime, to any grid user with guaranteed Quality of Service (QoS). Wireless grids extend the capability of grid computing to wireless devices. The number of users using laptops, PDAs, cell phones, and other wireless devices is increasing leading to more networked wireless devices, and creating a vast collective potential of unexploited resources. Wireless grid computing with its model of coordinated resource sharing may provide a way to utilize such resources that are normally distributed throughout a grid. Grid Computing will be the major area of focus in the future days. We may have Gridnet in the future as we have Internet today. In this survey paper, we tried to cover the entire spectrum of wireless grids: wireless grid computing, its architectures, challenges, communication paradigms, applications, and different standards related to grids.

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This paper carries out the mathematical analyses and implements linear restoration filters such as Inverse filter, Pseudo Inverse filter, Wiener filter, Constrained Least square filter. Linear filters are used to restore images that are blurred by spatial invariant degradation model and degraded by additive noise. The performance of each filter is considered based on the statistical parameter of the restored image. The analysis is carried out for each filter over a range of noise and blur. The filter transfer function is optimized to get a nearest estimate to the original image. The performance of each filter is compared and conclusions are presented.

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The paper describes the phase locked loop (PLL) in detail. Emphasis is on Digital Phase Locked loops (DPLL) and All-Digital Phase Locked Loops (ADPLL). Important parameters of the PLLs are described. Different sub-blocks of DPLL and ADPLL are described and discussed in detail. An example design of ADPLL is also discussed. Digital and All Digital PLLs are gaining popularity because of their ease of implementation in FPGA's and ASIC's.

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It is known that a parallel combination of a current source and a resistance can be replaced by a series combination of a voltage source and a resistance and vice versa according to the source transformation theorem. Thus, the source transformation gives only one current to voltage or voltage to current equivalent circuit. In this short paper, we show that there is a large number of current to voltage, voltage to current, current to current and voltage to voltage source transformations possible under certain given terminal condition. This result is not given in the text books.

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This paper is an attempt to present the work done on "design and development of a chip for automatically controlling unmanned railway crossing" which is a part of the series of our work named D-MANAV (Digital Manav). In order to develop a prototype, the design has been implemented on a Complex Programmable Logic Device (CPLD), which is reconfigurable. Timing and resource utilization details of the CPLD implementation are also discussed in the paper. D-Manav is designed in confluence with the economy of developing nations.

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This paper presents two pulse shapes. One pulse, obtained by amplitude modulating the Gaussian pulse by a modified sine pulse, offers much less intersymbol interference (ISI) than that offered by the Gaussian pulse modulated in amplitude by a sine pulse. The other pulse, obtained by convolving the modified sinusoidal frequency shift keying (MSFSK) pulse with a square pulse, requires lesser bandwidth than that required by the pulse, obtained by convolving the sinusoidal frequency shift keying (SFSK) pulse with a square pulse. The power density spectra of the proposed pulses are much narrower than those offered by the aforesaid pulses.

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This paper presents a pulse shape that is generated from error functions. For typical values of the parameters associated with the error functions, the proposed pulse resembles a Gaussian pulse. The mathematical analysis of the proposed pulse and its application in generating a trapezoidal pulse with smooth transitions for leading and trailing edges and variable width are presented.

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A simple derivation is given of a closed form formula for the computation of the coefficients of Chebyshev polynomials, which, as is well known, are required for the design of equal ripple filters. A modification of the formula is also given for facilitating fast computation.

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Conventional Kalman filter having constant velocity model (KFcv), conventional Kalman filter having constant acceleration model (KFca) and Interacting Multiple Model Kalman filter (IMMKF) having constant velocity & constant acceleration models were implemented and their performance was studied. Overall performance of IMMKF was better than the other two. The performance of IMMKF with different process noise variance, measurement noise variance and model transition matrix was explored. It was concluded that Ql and Q2 higher than their true would give better performance. The measurement noise variance R lesser than the true value gives improved results. The diagonal elements of model transition matrix derived from sojourn time shows superior performance. Results showed that, IMMKF exhibits overall better performance and was more suitable for tracking maneuvering targets than conventional Kalman filters.

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Group connections of three phase transformers are very important with respect to transformer operation in practice. It has been our experience as teachers while dealing with the topic for more than two decades that students often get confused mainly because they try to find out some sort of correlation between mechanical placement of windings and the corresponding voltage phasors. This confusion has a root in three phase A or Y voltages, where the mechanical positioning of windings and related phasors assume the same pattern. In this paper, group connections are 'revisited' starting from the basic principle of voltage induction and corresponding polarities via a down-to-earth approach.

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It is shown that the 'shadow' filter, introduced recently by Lakys and Fabre, is capable of achieving not only a constant bandwidth band-pass filter, but also several other interesting characteristics depending upon the choice of the desired output port and the port from which feedback signal is derived. Two such characteristics are illustrated in this paper, namely constant centre frequency, variable Q, and constant value of the product of centre frequency and Q. A problem is also posed for further investigation. Finally, a suggestion is made for the design of a simple but interesting experiment for undergraduate students, using only resistors, capacitors and op amps, which illustrates the basic concepts of filters and what the shadow technique can do to improve their quality.

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Connection of large wind generation to the power system has been resulted poor power quality and poor stability margins. After a severe disturbance occurrence characteristic of fixed speed induction generators, the instability in wind farms based on FSIG is severally created by the extreme reactive power absorption. This phenomenon is a result of rotor slip of FSIG increase during the fault, and consequently, the consumption of reactive power is increased. This requires that methods to improve power quality and stability for such systems. This paper investigates how a PSS and UPQC mitigate the speed oscillation and voltage fluctuations are created by faults in grid. The simulation results are carried out by PSCAD/EMTDC software and it demonstrate that power quality and the stability margin can be improved significantly for wind farms by UPQC.

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The matrix approach is extremely simple and systematic compared to the Miller's equivalent approach. It is a general approach and the conventional loop and node methods are special cases when there are no controlled sources. It explains how a reciprocal network is converted into a non-reciprocal one due to the presence of controlled sources. It not only gives the exact values for forward gain and input admittance but also gives exact values for reverse gain and output admittance without taking any special precaution.

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