International Journal of Computer and Applications

This document provides updates to IEEE Std 802.16's MIB for the MAC, PHY and asso- ciated management procedures in order to accommodate recent extensions to the standard.

IEEE Standard for Local and Metropolitan Area Networks Part 16: Air Interface for Fixed Broadband Wireless Access Systems Draft Amendment: Management Information Base Extensions

Advances in wireless communication technologies, such as wearable and implantable biosensors, along with recent developments in the embedded computing area are enabling the design, development, and implementation of body area networks. This class of networks is paving the way for the deployment of innovative healthcare monitoring applications. In the past few years, much of the research in the area of body area networks has focused on issues related to wireless sensor designs, sensor miniaturization, low-power sensor circuitry, signal processing, and communications protocols. In this paper, we present an overview of body area networks, and a discussion of BAN communications types and their related issues. We provide a detailed investigation of sensor devices, physical layer, data link layer, and radio technology aspects of BAN research. We also present a taxonomy of BAN projects that have been introduced/proposed to date. Finally, we highlight some of the design challenges and open issues that still need to be addressed to make BANs truly ubiquitous for a wide range of applications.

Body Area Networks: A Survey

The problem of idle listening is one of the most significant sources of energy consumption in wireless sensor nodes, and many techniques have been proposed based on duty cycling to reduce this cost. In this paper, we present a new asynchronous duty cycle MAC protocol, called Receiver-Initiated MAC (RI-MAC), that uses receiver-initiated data transmission in order to efficiently and effectively operate over a wide range of traffic loads. RI-MAC attempts to minimize the time a sender and its intended receiver occupy the wireless medium to find a rendezvous time for exchanging data, while still decoupling the sender and receiver's duty cycle schedules. We show the performance of RI-MAC through detailed ns-2 simulation and through measurements of an implementation in TinyOS in a testbed of MICAz motes. Compared to the prior asynchronous duty cycling approach of X-MAC, RI-MAC achieves higher throughput, packet delivery ratio, and power efficiency under a wide range of traffic loads. Especially when there are contending flows, such as bursty traffic or transmissions from hidden nodes, RI-MAC significantly improves throughput and packet delivery ratio. Even under light traffic load for which X-MAC is optimized, RI-MAC achieves the same high performance in terms of packet delivery ratio and latency while maintaining comparable power efficiency.

/pdf/ri-mac-a-receiver-initiated-asynchronous-duty-cycle-mac-4rb0jcbw11.pdf

RI-MAC: a receiver-initiated asynchronous duty cycle MAC protocol for dynamic traffic loads in wireless sensor networks

http://www.inf.ufes.br/~zegonc/material/Redes%20de%20Sensores%20sem%20Fio/MAC%20in%20WSN.pdf

Medium access control in wireless sensor networks

ABSTRACT OFDM-based Radio on Free space optical (RoFSO) system gained attention of technocrats and researchers due to high data rates, license-free spectrum and ease of installation among the others. However, it is noteworthy to mention that turbulence-induced fading and pointing error are the major challenges of RoFSO system. Although various literatures include pointing error and/or turbulence induced fading to present different performance measures of RoFSO system, none of them includes all the turbulence condition from weak to strong. In contrary, Double Generalized Gamma (DGG) distribution shows perfect fit over the entire range of turbulence conditions from weak to strong. This research work presents various closed form expressions of BER for M-QAM and K-PSK schemes over DGG distribution under weak, moderate and strong turbulence conditions for the system with and without pointing error. Furthermore, as DGG distribution includes different fading channels such as Double Weibull and Gamma-gamma distribution as its special case. Therefore, we reproduce BER of M-QAM and K-PSK modulation schemes with and without pointing error over Double Weibull and Gamma-gamma fading channels. Simulation shows that irrespective of severity of turbulence, pointing error and/or increase in the order of modulation scheme deteriorate the system performance.

ABER of M-QAM and K-PSK modulations over double-GG fading channel

One of the methods to solve the problem of spectrum demand is spectrum sharing and can be achieved using Cognitive Radio (CR) network. The problem in CR network is physical layer security. The physical layer security can be improved using relays in the secondary network. There are two types of relay slection schemes which are Single Relay Selection (SRS) and Multiple Relay Selection (MRS) schemes. In SRS and MRS schemes, the coordination between primary and secondary network is lost due to mutual interference which results in imperfect Channel State Information (CSI). In this paper,Transmit Antenna Selection (TAS) scheme in MIMO CR network has been proposed for improving the physical layer security compared to SRS and MRS schemes in CR network. The physical layer security is analyzed through Security Reliability Tradeoff (SRT) in terms of Outage Probability (OP) and Intercept Probability (IP) for SRS, MRS and TAS schemes. Simulation results show that SRT performance of TAS scheme in MIMO CR network is better than SRS and MRS schemes.

Transmit antenna selection in MIMO Cognitive Radio networks

A novel analytical model for interference estimation in CR‐enabled femtocells

As more than 50% of voice and more than 70% data applications starts from indoor. Therefore, Femtocells which is an indoor deployment has been presented as one of the important technologies to achieve the requirement of ever-growing data rate. However, spectrum scarcity has been always regarded as most challenging issue of wireless communication. This paper proposes an approach to utilize the given spectrum using fractional order of Fractional Fourier Transform (FrFT) in turn to increase the spectrum efficiency. ITU-R model and COST-231 model have been used for analysis of the proposed system. Results have been simulated in Matalab-14.

M. K. Lakshmanan

Papers

ABER of M-QAM and K-PSK modulations over double-GG fading channel

Transmit antenna selection in MIMO Cognitive Radio networks

A novel analytical model for interference estimation in CR‐enabled femtocells

Capacity Enhancement of Femtocell

Performance Investigation of Molecular Nano Communication Over Channels Under Dynamic Scenarios