This paper deals with multiple-input multiple-output (MIMO) broadband wireless communication systems, employing orthogonal frequency-division multiplexing (OFDM). In order to exploit the benefits of OFDM in highly frequency-selective channels, without any significant increase in receiver complexity, a channel shortening prefilter is inserted at the receiver. The main aim of inserting channel shorteners is to shorten the channel so that the main energy of the composite channel is concentrated within a duration smaller than the guard interval inserted while transmission. Thus by including channel shortening equalizers at the receiver the inter symbol interference or the inter block interference can be suppressed. The new approach proposed in this thesis is zero padding approach with Eigen decomposition approach. The advantages of the proposed approaches include immunity to delay spread, resistance to frequency selective fading and simple equalization. This shortening design is a blind one, i.e., a priori knowledge of the MIMO channel impulse response to be shortened is not required, and can be carried out in closed-form.

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Digital watermarking is a process for modifying physical or electronic media to embed a machine-readable code into the media. The media may be modified such that the embedded code is imperceptible or nearly imperceptible to the user, yet may be detected through an automated detection process. Watermarking is the art of imperceptibly embedding a message into a work. More than 700 years ago in Fabriano (Italy), paper watermarks appeared in handmade paper, in order to identify its provenance, format, and quality. In this context, the watermark is a kind of invisible signature that allows identifying the creator or the owner of a document, and to detect possible copyright violations, and especially non-authorized copying [1]. More recently, different watermarking techniques and strategies have been proposed in order to solve a number of problems, ranging from the detection of content manipulations, to information hiding (steganography), to document usage tracing. In particular, the insertion of multiple watermarks to trace a document during its lifecycle is a very interesting and challenging application [1]. The main property of the proposed method is that it allows the insertion of multiple watermarks by different users, who sequentially come into play one after the other and do not need any extra information besides the public keys. This characteristic makes the present approach more attractive than previously available solutions.

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In this paper, the metal clad optical waveguide polarizer have been analysed and presented. The metal's that were used are Gallium Arsenide and Aluminium for the cladding purpose of comparison and analysis. It was found that the variation between TE mode and TM mode when Gallium Arsenide is used as the cladding is less as compared to Aluminium. This is due to the metal cladding itself will cause a cut-off region in the polarizer. Gallium arsenide may have fewer modes compared to aluminium and which resulted in the variation of the graphs between the two metals used. We have also shown that there is a slight drop of the TM to TE loss ratio when the buffer layer thickness is increased. It was also found that the high extinction ratio results in the high and linear attenuation in the fiber.

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Multi-Target Tracking for Sensor Networks using Ant Colony Optimization is proposed in this paper. The proposed approach uses ant colony optimization technique that composed of both dynamic and mobile nodes. While mobile nodes are used for optimizing the target tracking, dynamic nodes ensure the total coverage of the network. As a result, the performance of the Wireless Sensor Networks with multi-target tracking on mobility nodes will improve. While improving the performance of the wireless sensor networks, automatically minimum distance will be travelled by the nodes, thereby decreasing the energy consumption of the mobility nodes. This is achieved by selecting the optimal path by searching each path of the existing network. The software should check whether any chance of collision and if it is happening, then how to avoid it by providing a minimum delay for finding the optimal path. For finding the prediction of each node to reach the optimal path different methods should be applied, like k-means and random selection. The experimental results show that Object tracking with prediction mechanism is much better than without prediction mechanism.

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OFDM is one of the multicarrier modulation technique used in various communication systems. The major problem one faces while implementing this system is the high peak to average power .For an efficient OFDM system this PAPR should be low. In this paper a hybrid PAPR (peak to average power ratio) reduction technique for the OFDM (orthogonal frequency division multiplexing) signal which combines a multiple symbol representations method with a signal clipping method is proposed. In multiple symbol representations alternative signaling points are used to represent one symbol and PAPR is further reduced with the clipping scheme. The performance of the hybrid scheme is compared with the partial transmit sequence which is one of the other PAPR reduction scheme. In partial transmit sequence the input data is divided in to disjoint blocks transformed in to time domain sequence and rotated by phase factors. Theoretical analysis and simulation results validate that the proposed scheme has the ability to provide large PAPR reduction, low bit error rate. Performance analysis is also done with the partial transmit sequence scheme.

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Fuel cell stacks containing hundreds of individual cells are capable of generating high voltage and current values needed for transportation, commercial, residential, portable and industrial power applications. Although majority of hydrogen produced today comes from reformulated natural gas generated through a process that creates a significant amount of carbon dioxide, fuel cell is still a viable energy source for the future electrical power applications. One of the hard cases of the fuel-cell power systems is proper monitoring, instrumentation and data acquisition of system parameters such as fuel flow into the system, AC and DC voltage values, load current, humidity, power, pressure, temperature, fuel utilization, overall system efficiency, noise, etc. Fuel cell test systems must precisely monitor and control the aforementioned hundreds of measurements in real-time. It is necessary to have an instrumentation system which is able to monitor and control fuel cell operation under varying conditions and accurately get information relating to real-time performance and operational characteristics to calculate fuel cell efficiency correctly. Instrumentation and interface systems must also provide flexible data acquisition, monitoring, and control capability to precisely control fuel cell operation. Therefore, a typical fuel cell test system requires high-resolution, high-voltage input, isolation, and waveform acquisition capability. The objective of this applied research project is design and implementation of a high-resolution data acquisition and interface module for a 500 W Hydrogen fuel cell power station using LabVIEW ™ PDS v8.20 software and field point based data acquisition modules.

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The multiplication is major arithmetic operation in signal processing and in ALU's .The multiplier uses look-up-table (LUT) as memory for their computations. However, we do not find any significant work on LUT optimization for memory-based multiplication. A new approach to LUT design was presented, where only the odd multiple storage (OMS) scheme. In addition to that the antisymmetric product coding (APC) approach, the LUT size is reduced to half and provides a reduction. When APC approach is combined with the OMS technique, the two's complement operations could be simplified since the input address and LUT output could always be transformed into odd integers, and thus reduces the LUT size to one fourth of the conventional LUT. The proposed LUT multipliers for word size L=W=5 bits are coded in VHDL and synthesized in Xilinx 14.2. It is found that the proposed LUT-based multiplier involves comparable area and time complexity for a word size of 5-bits.

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This article presents a review of the applications of Analytic Hierarchy Process (AHP). AHP is a multiple criteria decision-making tool that has been used in almost all the applications related with decision-making. Decisions involve many intangibles that need to be traded off. The Analytic Hierarchy Process (AHP) is a theory of measurement through pairwise comparisons and relies on the judgements of experts to derive priority scales. It is these scales that measure intangibles in relative terms. The comparisons are made using a scale of absolute judgements that represents how much more; one element dominates another with respect to a given attribute. The judgements may be inconsistent, and how to measure inconsistency and improve the judgements, when possible to obtain better consistency is a concern of the AHP. The derived priority scales are synthesised by multiplying them by the priority of their parent nodes and adding for all such nodes. An illustration is also included.

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In this paper, the spinning reserve (SR) capacity in a power system is considered to be flexible. The expected energy not served (EENS) is calculated by the equivalent energy approach. Based on the reliability evaluation of the generation system, a clearing model of the spinning reserve market is proposed to determine the optimal reserve capacity and simultaneously clear the spinning reserve market. The spinning reserve model for flexible spinning reserve is discussed on both uniform-price and pay-as-bid auction mechanisms. The results show that the flexible spinning reserve model is more beneficial than the fixed spinning reserve model and increases the social benefit of the system. For case studies reliability test system (RTS 96) is used in this paper.

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Multiple Input and Multiple Output (MIMO) and Orthogonal Frequency Division Multiplexing (OFDM) system have the potential to achieve very high capacity depending on the propagation environment. The objective of this paper is the adaptive resource allocation in MIMOOFDM system using the waterfilling algorithm. Water filling solution is implemented for allocating the power in order to increase the channel capacity. The total system capacity is maximised subject to the constraints on total power, signal to noise ratio, and proportional fairness. Channel is assumed as a flat fading channel and the comparison is made for different 2x2, 2x3, 3x2 and 4x4 MIMO-OFDM systems using waterfilling algorithm with allocated power. Also in order to prove that the MIMOOFDM with waterfilling algorithm provides the best performance a comparison with various SISO - OFDM is done.

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Orthogonal Frequency Division Multiplexing (OFDM) is an emerging field of research in the field of 4G broadband wireless communications due to its robustness against multipath fading and relatively simple implementation. Peak to Average Power Ratio (PAPR) is the limiting factor for an OFDM system as it consists of large number of independent subcarriers as a result of which the amplitude of such a signal can have high peak values which degrades the system performance. Such a signal when amplified by a Power Amplifier without processing results spectral regrowth and intermodulation among subcarrier. Hence this non linearity destroys the orthogonally of the OFDM signal and introduces out-of-band radiation and in band distortions causing significant performance degradation. The clipping and filtering method is analysed which is an efficient and simple method to reduce the PAPR. We have shown the effects of clipping and filtering on the performance of OFDM, including the power spectral density, the crest factor, and the bit-error rate.

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The proposed study is to develop an active suspension system to increase the comfort for the passenger by reducing the body acceleration. The dynamic quarter car suspension system is considered for mathematical modelling and simulation is carried using MATLAB SIMULINK. The present suspension system is controlled by Proportional- Integral -Derivative controller. The system performance is analysed using the single speed bump road surface and the effectiveness is evaluated with active and passive controlled systems.

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A supply planning for two-level assembly systems under lead-time uncertainties is considered. It is supposed that the demand for the finished product and its due date are known. It is assumed also that the component lead-time at each level is a random discrete variable. The objective is to find the release dates for the components at level two in order to minimize the expected component holding costs and to maximize the customer service level for the finished product. A multi objective approach is considered and numerical results are reported.

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A three phase three-level pulse width modulation (PWM) switched voltage source inverter with zero neutral point potential is designed. It consists of three single-phase inverter modules and each module is composed of a switched voltage source and inverter switches. The major advantage is that the peak value of the phase output voltage is twice as high as that of the conventional neutral-pointclamped PWM inverter. Thus, the proposed inverter is suitable for applications with low voltage sources such as batteries, fuel cells, or solar cells. Furthermore, three-level output waveforms of the inverter can be achieved without the switch voltage unbalance problem. Since the average neutral point potential of the inverter is zero, a common ground between the input stage and the output stage is possible. Therefore, it can be applied to a transformer-less power conditioning system. The SVS inverter is tested by a PSIM simulation and hardware is implemented and verified.

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In today's world of e-commerce, credit card payment is the most popular and most important mean of payment due to fast technology. As the usage of credit card has increased the number of fraud transaction is also increasing. Credit card fraud is very serious and growing problem throughout the world. This paper represents the survey of various fraud detection techniques through which fraud can be detected. Although there are serious fraud detection technology exits based on data mining, knowledge discovery but they are not capable to detect the fraud at a time when fraudulent transaction are in progress so two techniques Neural Network and Hidden Markov Model(HMM) are capable to detect the fraudulent transaction is in progress. HMM categorizes card holder profile as low, medium, and high spending on their spending behavior. A set of probability is assigned to each cardholder for amount of transaction. The amount of incoming transaction is matched with cardholder previous transaction, if it is justified a predefined threshold value then a transaction is considered as a legitimate else it is considered as a fraud.

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ARM introduced the Advanced Microcontroller Bus Architecture (AMBA) 4.0 specifications in March 2010, which includes Advanced extensible Interface (AXI) 4.0. AMBA bus protocol has become the de facto standard SoC bus. That means more and more existing IPs must be able to communicate with AMBA 4.0 bus. Based on AMBA 4.0 bus, we designed an Intellectual Property (IP) core of Advanced Peripheral Bus (APB) Bridge, which translates the AXI4.0-lite transactions into APB 4.0 transactions. The bridge provides an interface between the high-performance AXI bus and low-power APB domain.

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In this paper an effective direct torque control (DTC) for a 5-phase induction motor with sinusoidal distributed windings is developed. First by coordinate transformation, the converter/motor models are represented by two independent equivalent d-q circuit models; and the 5- phase VSI input are decoupled into the torque producing and non-torque producing harmonics sets. Then with the torque production component of the induction motor model, the space vector modulation (SVM) can be applied to the fivephase induction motor DTC control, resulting in considerable torque ripple reduction over the lookup table method. Based on the decoupled system model, the current distortion issue due to lack of back EMF for certain harmonics is analysed. Two equally effective SVM schemes with the harmonic cancellation effect are introduced to solve this problem. To analyse the DTC control torque ripple, an insightful perspective (also applicable to 3-phase analysis) is introduced to predict the torque ripple pattern evolution with changing motor speed and stator flux angular position. Therefore the switching sequence for lowest torque ripple can be determined and rearranged online.

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