A B C D E F G H I J K L M N O P Q R S T U V W X Y Z All
Lakshmanan, M.
- Design of Enhanced Cross-Layer Handoff Management Protocol for Next Generation Wireless Systems
Authors
1 School of Electrical Sciences of VIT University, Vellore–632014, Tamil Nadu, IN
2 School of Electrical Sciences of VIT University, Vellore – 632014, Tamil Nadu, IN
Source
Networking and Communication Engineering, Vol 1, No 5 (2009), Pagination: 193-199Abstract
In Next-generation wireless systems (NGWS), different wireless network is integrated and each of the networks is optimized for some specific services to provide ubiquitous communications to the mobile users. It is an important and challenging issue to support seamless handoff management in this integrated architecture. This paper deals about design of enhanced cross-layer handoff management protocol HMP) and is developed to support seamless intra and intersystem handoff management in NGWS. Cross-layer handoff management protocol uses mobile’s speed and handoff signaling delay information to enhance the handoff performance of Mobile IP in terms of probability of false handoff initiation and probability of handoff failure. Firt, thehandoff performance of Mobile IP is analyzed with respect to its sensitivity to the link layer (Layer 2) and network layer (Layer 3)parameters. Then enhanced cross-layer handoff management architecture is developed using the insights learnt from the analysis.Finally, simulation results show that CHMP significantly enhances the performance of both intra and intersystem handoffs independent of mobile terminal velocity and network handoff latency.
Keywords
HMP, Link Layer, Mobile IP, Network Layer and NGWS.- Frequency Domain Equalization for Single Carrier Wireless Systems
Authors
1 School of Electrical Sciences of VIT University, Vellore–632014, TamilNadu, IN
Source
Networking and Communication Engineering, Vol 1, No 4 (2009), Pagination: 177-183Abstract
Computational complexity and error propagation phenomenon are important drawbacks of existing Decision Feedback Equalizers (DFE) for dispersive channels. A new Iterative Block DFE (IBDFE) is considered where the equalization is performed iteratively on blocks of received signal in the frequency domain i.e. both signal processing and filter design are in frequency domain. Thus computational complexity is reduced and error propagation is limited to one block. The feed forward and feedback filters of DFE are designed with the minimization of Mean Square Error (MSE) at detector input as the parameter for effective detection. Two design methods have been solved and simulated for a Rayleigh fading channel. Channel is assumed to be time in-variant during one block of data (128 symbols) transmission. In the first method, the hard detected data are used as the input to the feedback, and filters are designed according to the correlation between detected and transmitted data. In the second method, the feedback signal is directly designed from soft detection of the equalized signal at the previous iteration. Estimates of the parameters involved in the FF and FB filters are also solved and used to evaluate the filter coefficients. From simulation, it was found that the IBDFE as claimed in the research literature performs better than the time domain DFE.
Keywords
DFE, IBDFE, OFDM and Raleigh Fading Channel.- Waves and Oscillations in Nature:An Introduction
Authors
1 Centre for Nonlinear Dynamics, Bharathidasan University, Tiruchirappalli 620 024, IN
Source
Current Science, Vol 110, No 12 (2016), Pagination: 2306-2307Abstract
Natural phenomena are dominated by the occurrence of oscillations and waves, whether it is light propagation, water wave disturbance, magneto hydrodynamics or plasma oscillations. There are many common features encompassing wave propagation and oscillatory behaviours in these diverse systems.- Spectrum Sharing and Inter Cell Interference Mitigation in Wireless Cellular Networks
Authors
1 School of Electronics Engineering, VIT University, Vellore - 632014, Tamil Nadu, IN
2 Department of ECE, Rajalakshmi Engineering College, Chennai - 602105, Tamil Nadu, IN
Source
Indian Journal of Science and Technology, Vol 9, No 35 (2016), Pagination:Abstract
Objective: Spectrum shortage and Inter Cell Interference (ICI) are two factors which limits the performance of wireless cellular networks. Methods/Analysis: One of the popular methods is Soft Frequency Reuse which effectively controls the spectrum management and reduces the ICI for wireless networks. In conventional static Soft Frequency Reuse (SFR) scheme, transmission power in cell and allocation of subcarriers are fixed during the system deployment, which affects the performance of system. Findings: This paper focuses Intercell Resource Allocation algorithm, which is dynamic in nature and optimizes both subcarrier and transmission power for cellular network. Novelty/Improvement: Intercell Resource Allocation algorithm result in greater improvement in data rate and system capacity.Keywords
Intercell Interference (ICI), Long-Term Evolution (LTE), LTE-Advanced (LTE-A), Soft Frequency Reuse (SFR), Spectrum Management.- Energy Control in 4G Networks
Authors
1 School of Electronics Engineering, VIT University, Vellore - 632014, Tamil Nadu, IN
2 Department of ECE, Rajalakshmi Engineering College, Chennai- 602105, Tamil Nadu, IN
Source
Indian Journal of Science and Technology, Vol 9, No 35 (2016), Pagination:Abstract
Objective: The design of wireless networks mainly focuses on resource allocation and energy efficient schemes to meet the increasing demands. Methods/Analysis: In this paper, we proposed an algorithm for Resource block (RB) allocation and Transmit power control in Long term evolution (LTE) downlink heterogeneous networks. Findings: Energy efficiency is increased by increasing the number of smaller cells. To satisfy the required user throughput energy efficiency is minimized and suitable resource block allocation is maximized. Novelty/Improvement: In the proposed power control algorithm, user is allowed to select minimum powers to reduce power of Evolved NodeB (eNB).Keywords
Energy efficiency (EE), LTE, Macro (MeNB), Resource Block (RB), Small eNodeB (SeNB).- Anjan Kundu (1953–2016)
Authors
1 Centre for Nonlinear Dynamics, Bharathidasan University, Tiruchirappalli 620 024, IN
2 Saha Institute of Nuclear Physics, Kolkata 700 064, IN
Source
Current Science, Vol 112, No 04 (2017), Pagination: 865-866Abstract
On 31 December 2016, India lost one of its finest mathematical physicists, Professor Anjan Kundu, who breathed his last during a visit to Bengaluru.- A Data Envelopment Analysis Approach to Performance Efficiency of Intellectual Capital – Case of Titan Company Limited#
Authors
1 DJ Academy for Managerial Excellence, Coimbatore – 641032, Tamil Nadu, IN
2 DJ Academy for Managerial Excellence, Coimbatore - 641032, Tamil Nadu, IN
Source
SDMIMD Journal of Management, Vol 9, No 1 (2018), Pagination: 1-8Abstract
The purpose of this paper is to value the Performance efficiency of Intellectual Capital (IC) on Financial performance indicators of Titan Company Limited. Data required for analysis were collected from the Annual reports of the company for a period of twenty years. This study uses a DEA – CCR – Output Model which consist of intellectual capital indices as input and financial performance measures as output. Results of the efficiency analysis reveals that of the 20 years studied, only 6 years (2007, 2011, 2012, 2013, 2015, and 2016) were found to be the best performing years in terms of harnessing the goodness of intellectual capital. Some years were very close to perfect efficiency score of one, but the rest of the years showed very poor utilisation of intellectual capital to impact financial performance.
Keywords
Intellectual Capital Efficiency, VAICTM, Value Addition, DEA, Efficiency Scores, Efficiency Frontier.References
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Authors
1 Centre for Nonlinear Dynamics, Bharathidasan University, Tiruchirappalli 620024, IN
Source
Current Science, Vol 115, No 5 (2018), Pagination: 992-993Abstract
On 11 August 2018, the country lost one of the most promising and dynamic upcoming researchers. Kuppuswamy Porsezian, Professor of Physics, Pondicherry Central University, breathed his last at Apollo Hospitals, Chennai due to an unexpected and sudden liver condition at the rather young age of 55. He was destined to achieve greater heights in science but nature snatched him quite unexpectedly leaving his loving family, colleagues, students and a large circle of friends in India and abroad in great despair.- Dynamical Modelling and Analysis of COVID-19 in India
Authors
1 Centre for Nonlinear Science and Engineering, School of Electrical and Electronics Engineering, SASTRA Deemed University, Thanjavur 613 401, IN
2 Department of Nonlinear Dynamics, School of Physics, Bharathidasan University, Tiruchirappalli 620 014, IN
Source
Current Science, Vol 120, No 8 (2021), Pagination: 1342-1349Abstract
We consider the pandemic spreading of COVID-19 in India after the outbreak of the coronavirus in Wuhan city, China. We estimate the transmission rate of the initial infecting individuals of COVID-19 in India using officially reported data at the early stage of the epidemic with the help of the susceptible (S), exposed (E), infected (I), and removed (R) population model, the so-called SEIR dynamical model. Numerical analysis and model verification are performed to calibrate the system parameters with official public information about the number of people infected, and then to evaluate several COVID-19 scenarios potentially applicable to India. Our findings provide an estimation of the number of infected individuals in the pandemic period of timeline, and also demonstrate the importance of governmental and individual efforts to control the effects and time of the pandemic-related critical situations. We also give special emphasis to individual reactions in the containment process.Keywords
Containment Process, COVID-19 Pandemic, Dynamical Modelling, Numerical Analysis.References
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