In order to meet the ever increasing demand for larger transmission bandwidth, wireless network based on radio-over-fiber technologies is a very beneficial solution. The IEEE 802.11a standards using Orthogonal Frequency Division Multiplexing (OFDM) can provide data rates up to 54Mbps which makes good for high speed communications in wireless local area networks. In this paper, ...

In the present paper wireless sensor network for hierarchical network protocol of LEACH and HEED this is theory concept that how to data gathering. The authors’ protocol aims to dynamically change the data Gathering period according to the Gathering quality. The timing scheme will find the minimum Gathering period that satisfies the sink’s request. This ...

Orthogonal Frequency Division Multiplexing (OFDM) is a modulation schema that due to the high spectral efficiency and the simplicity of the receiver implementation is the most common system for using in broadband communication systems. Although OFDM has been used in numerous wireless communication systems, but two of the main problems that are needed to be ...

Radio Frequency IDentification technology (RFID) is a non-contact intelligent identification system, its main advantage lies in the wide range of recognition, information capacity, security, excellent resistance to abrasion, reusable. It can take place of the traditional bar code recognition technology, and be applied to the area of modern intelligence logistics management. This paper introduces the ...

Pseudo Noise sequences (PN) are widely used in telecommunications and for measurement purposes. In this paper, cross correlation results of PN family codes: Gold, Kasami sequences are shown. PN sequences have random like properties that help in reducing the correlation among speech samples. In Spread Spectrum CDMA system each user is assigned a pseudo noise ...

As the nodes are rely on batteries or exhaustive energy sources for power and drop out within an ad hoc network, since energy sources have a limited lifetime. As the power availability is one of the most important constraints for the operation of the ad hoc network. In this paper, the authors present performance evaluation ...

Reducing the energy consumption of available resources is still a problem to be solved in Wireless Sensor Networks (WSNs). Many types of existing routing protocols are developed to save power consumption. In these protocols, cluster-based routing protocols are found to be more energy efficient. A cluster head is selected to aggregate the data received from ...

Back in the days of wireline telephony, when all phone calls went over the Public Switched Telephony Network (PSTN), businesses would purchase “trunks” -dedicated lines or a bundle of circuits – from their service provider. Back in the days of wireline telephony, when all phone calls went over the Public Switched Telephony Network (PSTN), businesses ...

Touch input has been extensively studied. The influence of display orientation on users’ performance and satisfaction, however, is not well understood. In an experiment, the authors manipulate the orientation of multi-touch surfaces to study how 16 participants tap and drag. To analyze if and when participants switch hands or interact bimanually, they track the hands ...

Peak-to-Average Power Ratio (PAPR) is an important parameter for the analysis of Orthogonal Frequency Division Multiplexing (OFDM) signals. CCDF curves are known to have great importance in the study of signal performance on the basis of power level. This paper presents the CCDF performance of the OFDM signal with different number of carriers. Simulation is ...

A new wireless sensor networking technology, DASH7 uses the ISO/IEC 18000-7 standard for active RFID. It operates in the 433 MHz unlicensed spectrum. DASH7 provides many advantages over other wireless technologies such as multi-year battery life, dynamic range of up to 2 Km (potentially farther) etc.DASH7 is the name of the technology promoted by the ...

This research proposes a new efficient load balancing algorithm which applies to the local Domain Name Service (DNS) server for web based applications and services to ease the sudden increase in demand for the services. Owing to the existing load balancing algorithms still experience server’s resource congestion and slow connection to the system resulted by ...

In this paper, the authors propose a composite right/left handed double periodic transmission line structure with both inductance and capacitance loaded. The structure exhibits leaky wave radiation and hence can be considered for Leaky Wave Antenna (LWA) applications. They have theoretically obtained dispersion characteristics using singular perturbation method. Also, the radiation efficiency has been obtained ...

Passwords are a known weak link and continue to be exploited at alarming rates. From simple phishing schemes to sophisticated, targeted phishing attacks, gaining access to a user’s password is an easy and prolific attack. Regulatory agencies agree and are setting increasingly rigorous requirements for strongly authenticating users. Multi-factor authentication is no longer optional for ...

Location based personalized recommendation has been introduced for the purpose of providing a mobile user with interesting information by distinguishing they preference and location. In most cases, mobile user usually does not provide all attributes of their preference or query. In extreme case, especially when mobile user is moving, the user even does not provide ...