Simulation Analysis of Tree and Mesh Topologies in Zigbee Network

Manpreet,Jyoteesh Malhotra 보안공학연구지원센터 2015 International Journal of Grid and Distributed Comp Vol.8 No.1

Recently wireless sensor Network (WSN) and wireless personal area network (WPAN) has gained lot of interest from the research community because of its diverse applications of controlling, monitoring and automation of home, offices or any rescue area. Zigbee based on IEEE 802.15.4 standard is key enabling technology for the success of both WSN and WPAN. Zigbee has some inherent powerful characteristics like very low power consumption, localization and low cost that has drawn the attention of research community recently. Along with merits come the challenges for the success of Zigbee based networks at various layers of the network model. Network topologies in Zigbee are to be selected based on applications and performance requirements. So this paper investigates the performance of Zigbee for tree and mesh topologies. In doing so parameters like MAC throughput, MAC load, MAC delay, end to end delay have been evaluated through extensive simulations using OPNET. The intricate behavior of these topologies in Zigbee shows optimum bounds of performance for these topologies have been computed in this work

Effect of Fading on Performance of VANET in Realistic Scenarios Using NCTUns6.0

Richa Sharma,Jyoteesh Malhotra,Komal Sharma 보안공학연구지원센터 2015 International Journal of Future Generation Communi Vol.8 No.1

Road safety and increasing transport efficiency are the important goals for intelligent transport system (ITS). Vehicular Ad hoc Network is such a network which can help to achieve these goals. VANET routing is a crucial task for reliable communication among vehicles. The impact of fading on network throughput and packet drop is explored in this paper. Interesting results show the performance evaluation of without fading environment and Rayleigh fading in different scenarios. NCTUns 6.0 (National Chiao Tung University Network Simulator) is used to justify our results that is a GUI based open source platform for vehicular Ad-Hoc network. Various performance issues are also surveyed with the help of this simulator.

An Efficient Design of a DC-Block Band Pass Filter for the L-Band

Avneet Kaur,Jyoteesh Malhotra 한국전기전자재료학회 2017 Transactions on Electrical and Electronic Material Vol.18 No.2

In this paper, three DC Block designs are presented which efficiently meet the need of modern-day compactsizewireless communication systems. As one of the important parts of a complete system design, the proposedmicrostrip-based DC block with coupled transmission lines efficiently attenuates unwanted frequencies that causedamage to the system. The compact-sized DC block structures are created by incorporating an extended coupled-linesection with a radial stub, an enveloped coupled-line section, and using alternate up-down meandering techniques. The structures are analyzed for the L-Band using a high-resistive silicon substrate. At a resonating frequency of 1.575GHz, the designed DC Block structures have a return loss better than -10 dB, an insertion loss of around -1 dB, andalso possess wide pass-band characteristics.

A Survey on Rate Adaptation Algorithms for Effective Resource Utilization in LTE Advanced

Diksha Duggal,Jyoteesh Malhotra 보안공학연구지원센터 2015 International Journal of Future Generation Communi Vol.8 No.3

LTE Advanced has brought revolution in the field of wireless communication technology by providing high data rates of up to 1Gbps. There is a need of increased data rates these days that may support the delivery of richer mobile multimedia contents to the end users. Rate adaptation is one of the key enabling technology in the success of LTE Advanced that has cited attraction of academia and research communities in recent years. Rate adaptation is the determination of the optimal data transmission rate most suitable for current prevailing wireless channel conditions. To maximize the performance of wireless devices, it is important to select the best appropriate rate hence rate adaptation algorithms (RAA’s) are required. This work includes a comprehensive survey on various types of RAA’s in LTE-A for effective resource utilization. Depending on the channel conditions various performance parameters such as throughput, power consumption and latency have been studied. It has been observed from the literature survey that many proposals have been published on LTE-A. Sill there is a need of research to be carried in LTE-A as this technology is not fully matured so open issues and future scope are also raised in this work.

Error Rate Performance Investigations of MIMO Transmission Modes through Nakagami-m Fading Channels

Rachna Mahey,Jyoteesh Malhotra 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.8

In the field of wireless communication systems, the use of multiple antennas at the transmitter and receiver side has gained a huge popularity over the past few decades, due to its tremendous performance enhancing capabilities. Such systems are known as MIMO (Multiple-Input Multiple-Output) systems and can be classified into three main categories; Spatial Multiplexing, Spatial Diversity and Beam forming techniques. The objective of this paper is to evaluate the error rate performance of MIMO transmission modes through Nakagami-m fading channels. The ZF (Zero Forcing), MMSE (Minimum Mean-Square-Error) channel equalization algorithm; STTC (Space Time Trellis Codes), OSTBC (Orthogonal Space Time Block Codes), MRC (Maximal Ratio Combining) and Beamforming methods are analyzed. The QPSK modulation technique is used to evaluate the bit error rate (BER) performances under different SNR scenarios. The results described in this paper suggest considerable improvement in the system performance by incorporating different MIMO techniques in order to improve the wireless transmission link quality.

Review on Security Issues and Attacks in Wireless Sensor Networks

Lovepreet kaur,Jyoteesh Malhotra 보안공학연구지원센터 2015 International Journal of Future Generation Communi Vol.8 No.4

Wireless sensor network is a collection of sensor nodes with limited processor and limited memory unit embedded in it. Sensor networks are used in wide range of applications such as Environment monitoring, health, industrial control units, military applications and many more. This paper defines the security requirements and various attacks on sensor network. This paper also review proposed security mechanisms for WSN.

Simulative Investigations for Robust Frequency Estimation Technique in OFDM System

Kussum Bhagat,Jyoteesh Malhotra 보안공학연구지원센터 2015 International Journal of Future Generation Communi Vol.8 No.4

OFDM (Orthogonal Frequency Division Multiplexing) is a promising technique for 4G and 3GPP LTE system in terms of providing the higher data rate and efficient use of bandwidth. But OFDM suffers from ISI and ICI interferences in wireless and fading environment. There is a loss of certain amount of data because of these interferences, thus synchronization is required. It is important to estimate and correct the start of OFDM symbol efficiently to reduce timing and frequency offset errors. The paper mainly focus on the CFO problem present in OFDM system, describes the effect of CFO in OFDM system and provides the estimation techniques for CFO in time domain and frequency domain. The simulation results are performed for the CFO estimation technique with different values of CFO and then results has been compared.

Performance Evaluation of MAC Aware QOS Provisioned Hybrid Routing over VANET

Aarja Kaur,Jyoteesh Malhotra 보안공학연구지원센터 2015 International Journal of Future Generation Communi Vol.8 No.5

A vehicular ad-hoc network adopts some attributes of MANET and provides communication between high speed vehicles. VANET based communication can be classified into three categories i.e. Vehicle to Vehicle (V2V), Vehicle to Infrastructure and Hybrid which combines both V2V and V2I schemes. VANET has the potential of achieving goals of intelligent transport system (ITS) increasing road safety and transport efficiency. VANET though being a sub-class of MANET has distinguishing features that make routing in VANET a baffling problem. Timely and accurate information dissemination is the primary concern. QoS guaranteed routing with minimum packet collisions will increase the efficiency and throughput of the channel. Back-off algorithms are used to reduce the number of collisions when nodes try to access the channel simultaneously. In this paper, we deployed a back-off method called Modified Back-off algorithm (MBA) in the MAC layer of IEEE 802.11p. The simulations are carried out using NS-2 in order to study the behavior of hybrid routing protocol, ZRP with two different back-off mechanisms utilized at the MAC layer. Evaluations are done using Nakagami propagation model with different vehicle densities and packet sizes. The performance is investigated in terms of throughput, packet delivery ratio, routing load and end to end delay.

Range Free Localization Techniques for Randomly Deployed WSN-A Survey

Ravneet Kaur,Jyoteesh Malhotra 보안공학연구지원센터 2015 International Journal of Grid and Distributed Comp Vol.8 No.6

Recent advancements in MEMSs technology, VLSI and wireless private area networks have contributed in developing enormous interest in wireless sensor networks by both academia and research community. WSN is formed by large number of small, cheap and low energy sensors that work together in monitoring region. These sensors sense, collect and forward data within the network through wireless medium. WSN find its application in many areas such as object tracking, disaster relief and smart environments etc. Most of these applications need location awareness of sensor nodes to estimate the place of origin of events. The task of determining physical coordinates of sensor nodes within the network is known as localization. Localization has always remained a challenge in successful implementation of WSN and so, it is a hotspot of research. Localization techniques are broadly categorized as Range based techniques and Range-free techniques based on their dependency on range measurements. Because of constraints on cost, energy, computation complexity and infrastructure requirements, range free localization techniques are given importance in recent research works. Considering the latest trends in localization, a thorough analysis for major range free techniques is done in this paper and accordingly their pros and cons are highlighted. As the existing range free techniques are not fully efficient so, open issues are also raised to give directions to future research.

RF-MEMS-Based DPDT Switch on Silicon Substrate for Ku-Band Space-Borne Applications

Harsimran Singh,Jyoteesh Malhotra 한국전기전자재료학회 2017 Transactions on Electrical and Electronic Material Vol.18 No.1

A RF-MEMS (radio-frequency microelectromechanical-system) based DPDT (double pole double throw) switch forthe Ku band has been designed and analyzed for this article. The switch topology is based on the FG-CPW (finiteground-coplanar waveguide) configuration of a microstrip-transmission line. An FEM-based multiphysics solver isused for the evaluation of the spring constant, stress distribution, and pull-in voltage regarding the requirementsof the switch-beam unit. The electromagnetic performance of the switch is investigated for a 675 μm thick siliconsubstrate. For the operational frequency of 14.5 GHz, an insertion loss better than -0.3 dB, a return loss better than -40dB, and input/output- and output-port isolations better than -35 dB are achieved for the switching unit.