Kishore Kulat

Robust Algorithms for DOA Estimation and Adaptive Beamforming for Smart Antenna Application

This paper presents a tool for the modelling, analysis and simulation of direction-of-arrival (DOA) estimation and adaptive beamforming needed in the design of smart antenna arrays for wireless mobile communications. In this paper performance of adaptive beamforming algorithm has been studied for two different DOA estimation algorithms namely MUSIC & MVDR. MUSIC estimates the number of incident signals on the array and their directions of arrival. It also gives the direction of arrival of desired signal. The Minimum Variance Distortion less Response (MVDR) is a very well known algorithm to obtain the optimum weight vector, which maximizes the output signal to noise and interference ratio (SNIR) of multiple antennas. The LMS algorithm, which has been simulated, is a simple yet efficient technique for robust adaptive beamforming. The LMS algorithm recursively computes and updates the weight vector. It has been observed that LMS algorithm gives the response for the two different DOA estimation algorithms MUSIC & MVDR depending upon the DOA estimations.As the signals are randomly generated the response of LMS algorithm differ for some cases of DOA estimations using MUSIC & MVDR otherwise it gives same response for both the algorithms. The algorithms have been simulated in MATLAB 7.4 version. A simulation tool with a graphical user interface, which implements these algorithms, is developed. Results of numerical simulation are useful for the design of smart antennas systems with optimal performance.

SDR design for cognitive radio

Software Defined Radio (SDR) is one of possibilities to realize the structure of device with a high mobility, flexibility and reconfigurability. This technology can provide the seamless shifting between existed air-interface standards. Extending the flexibility further, a system capable to sense the spectrum space available for communication and adapt to it is Cognitive Radio. Obviously SDR in Cognitive Radio should be configured not only to independent standards, protocols and services but also to the extensively dynamic nature of bandwidth allocation. Moreover this need of dynamic allocation of Spectrum space is a must to cater to its increased demand. Cognitive radio is envisioned as the ultimate system that can sense, adapt and learn from the environment in which it operates. Sensing the available bandwidth an SDR (Software defined radio) in a Cognitive System, tunes the circuits in the System for transferring data at optimum data rates, permissible by the space available. So it is a must for the SDR to accordingly add processing circuits to maintain the System performance at variable working frequencies. This paper discusses the critical issue of designing the SDR for the Cognitive radio and also presents some useful results obtained to configure the SDR for higher bandwidth available in Cognitive Radio. Results of Frequency Hopping Spread Spectrum (FHSS) implementation, Codec Algorithm modifications, and decoder iterations variation and performance improvement using OQPSK are depicted in the paper.

Environmental Monitoring Using Wireless Sensors: A Simulation Approach

Environmental monitoring is an area of significant research in the field of wireless sensor networks. It has the potential to reveal fine-grained, dynamic changes in monitored variables of an outdoor landscape. A network of sensor nodes spread across a field has the capacity to provide temporal and spatial data regarding the properties of the environment. For example, sensor networks could provide precise information about crops with respect to the soil quality and water content, enabling better irrigation schedules, pesticide usage and enhancing environment protection. The current paper presents a snapshot of sensor network, which can be deployed to monitor vital properties like temperature, relative humidity & soil moisture and then report them through a routing tree to a base station for further analysis. The minimum delay scheduling algorithm is discussed & compared with V-blast algorithm. It has been observed that the later one gives the precise results to monitor an environment. The importance of monitoring our physical environment has never been higher. Many groups - from agricultural operators to natural resource developers to biological researchers to homeland security - all need to make reliable, sensitive measurements in remote or dispersed locations. Some of the harshest and most demanding applications are- irrigation management ,harvest timing ,bio-remediation and containment, water quality measurement and control . In this paper, the parameter that we have taken is environmental temperature.

A Significance of VLSI Techniques for Low Power Real Time Systems

In microelectronics design, power consumption, speed of operation, are crucial constraints. Propagation delay of circuit component has an impact on such factors. Pipelining and parallel processing strategies are utilized for desirable propagation delays and hence for clock and throughput variation respectively. To some extent variation in propagation delay is responsible for power consumption reduction. In this paper, pipelining and parallel processing concepts are analyzed with reference to task scheduling in real time system. Power consumption and speed of operation issues of such systems are analyzed.

Algorithmic Trading (AT) - Framework for Futuristic Intelligent Human Interaction with Small Investors

Algorithmic trading has become more popular with large institutional investors these days. Big investment giants and top corporate notches are taking undue advantage of these algorithms over small investors. The one of the most critical factor which is limiting small investors to use these algorithms is lack of interactive user interface. This paper proposes a framework for intelligent interaction of these trading algorithms with the user which maintains required user adaptability, modeling and knowledge sharing in the coming future. Further the paper discuss about the various trading algorithms, their areas of concern and its likely impact on the market presently and in coming future. The full text of the article is not available in the cache. Kindly refer the IJCA digital library at www.ijcaonline.org for the complete article. In case, you face problems while downloading the full-text, please send a mail to editor at editor@ijcaonline.org

Video encoding techniques based on 3D-DWT

This paper deals with the application of Spatial and Temporal DWT (Discrete Wavelet transform) on the videos. Here we will discuss about three mechanisms and their performance on videos at increased DWT level. In any video processing algorithm, memory is the major criteria. In these three mechanisms dynamic (automatic) DWT level selection and manual level selection is implemented. Here we will also discuss about implementation of different DWT level in spatial and temporal domain. In this paper Haar wavelet is taken as the reference as it has its inherent properties and ease of implementation.

Lifetime Maximization in Wireless Sensor Network Using Cross Layer Design: A Design Review

In our paper we consider the comparison performance of wireless sensor network to optimize the event detection and TDMA schemes using cross layer interaction. We consider the accuracy and lifetime of WSN because accuracy and lifetime are the important parameters of wireless sensor network because working of system depends upon it. Lifetime maximization relates with various factors such as throughput, end to end delay, lifetime parameter such as time, output, packet delivery rates, no. of nodes, nodes efficiency, operating frequency to operate and relate each parameter. It is very difficult to study and compare all the above parameters simultaneously in the Wireless Sensor Network. So throughput is end to end delay or packet delivery of nodes can be verified any improvement in one of the parameter so that it can optimized the operation capability of the whole wireless network. Depending upon the no. of nodes corresponding hoping is developed. Routing through no. of hopes can disturbed the lifetime of WSN.

Design Overview Of Processor Based Implantable Pacemaker

Implantable pacemaker is a battery operated real time embedded system, which includes software/hardware codesign strategy. As it is placed within the heart by surgery, battery life is an important constraint to extend device lifetime. In this paper, pacemaker’s functionalities like basic pacing, pulse width, refractory period in VOO mode has been realized using ultralow power processor MSP 430F1611 and IAR workbench. Software related instruction level instantaneous current is measured and Current/Energy performance, battery longevity is tested. It is verified that, change in pure cost and interinstruction cost (current/Energy) varies from 2.0 to 3.0 %. This methodology seems to be an innovative concept in software related energy estimation of such power critical real time system.

BER performance maintenance at high data rates in cognitive radio

Increased demand on the usable Spectrum and its current underutilization by the licensed users has given birth to dynamic spectrum allocation technology. This booming technology of dynamic spectrum allocation, popularly known as cognitive radio has setup new horizons in the field, to explore and to work on. Cognitive radio is envisioned as the ultimate system that can sense, adapt and learn from the environment in which it operates. Sensing the higher bandwidth an SDR (Software defined radio) in a Cognitive System, tunes the circuits in the System for transferring data at higher data rates. At such increased data rates the BER (Bit Error Rate) performance may degrade. So it is a must for the SDR to accordingly add processing circuits to maintain the BER. One such option has been explored and worked on. It is by using the FHSS (Frequency Hopping Spread Spectrum technique) that one can maintain the BER performance at increased data rates. Earlier work includes the use of higher bandwidth available for increasing the coding bits and thereby making the data more secure. In other words availability of higher bandwidth in Cognitive radio can be utilized either to increase the actual data rate (Yet maintain the BER) or to improve the BER performance & maintain the original data rate. Results of FHSS implementation by Matlab M-file programming and improved BER performance by adaptive coder both have been depicted in the paper. In fact present paper is an outcome of the doctoral research on Error Control Coding for performance improvement in BER.

Comparative analysis of video compression mechanisms using 3D-DWT with EZW

In this paper, two compression mechanisms based on 3D-Discrete Wavelet Transform (DWT) and 2D Embedded Zero Wavelet (EZW) are compared depending on the mathematical parameters Peak Signal-to-Noise Ratio (PSNR) and compression ratio(CR). In this paper, we are using Haar wavelet decomposition for compression, as it has shown improved compression in recent years when used with the techniques like EZW, SPIHT etc. Haar wavelet is chosen because of its ease of implementation and inherent properties and EZW is chosen for compression. We apply EZW frame-by-frame on the encoded video as it is meant for 2D-data only. Here we are adding the extra blocks for video encoding and decoding before and after the existing compression technique i.e., EZW. So, these mechanisms are very easy to implement by just adding the extra blocks of encoding and decoding.