Dynamic Approach To Enhance Performance Of Orthogonal Frequency Division Multiplexing(OFDM) In A Wireless Communication Network
Journal Title: International Journal of Advanced Computer Science & Applications - Year 2011, Vol 2, Issue 2
Abstract
In the mobile radio environment, signals are usually impaired by fading and multipath delay phenomenon. This work modeled and simulates OFDM in a wireless environment, it also illustrates adaptive modulation and coding over a dispersive multipath fading channel whereby simulation varies the result dynamically. Dynamic approach entails adopting probabilistic approach to determining channel allocation; First an OFDM network environment is modeled to get a clear picture of the OFDM concept. Next disturbances such as noise are deliberately introduced into systems that are both OFDM modulated and non-OFDM modulated to see how the system reacts. This enables comparison of the effect of noise on OFDM signals and non-OFDM modulated signals. Finally efforts are made using digital encoding schemes such as QAM and DPSK to reduce the effects of such disturbances on the transmitted signals. In the mobile radio environment, signals are usually impaired by fading and multipath delay phenomenon. In such channels, severe fading of the signal amplitude and inter-symbol-interference (ISI) due to the frequency electivity of the channel cause an unacceptable degradation of error performance. Orthogonal frequency division multiplexing (OFDM) is an efficient scheme to mitigate the effect of multipath channel.
Authors and Affiliations
James Agajo , Isaac O. Avazi Omeiza , Idigo Victor Eze , Okhaifoh Joseph
QoS Analysis to Optimize the Indoor Network IEEE 802.11 at UNTELS
This paper arose from the need to improve mobility and connectivity to network users of the Universidad Nacional Tecnológica de Lima Sur and the problems that arise on the quality of services (QoS) such as signal intermi...
Comparative Study of Data Sending Methods for XML and JSON Models
Data exchange between different devices and applications has become a necessity nowadays. Data is no longer stored locally on the device, but in the cloud. In order to communicate with the cloud and exchange data, web se...
Towards Securing Medical Documents from Insider Attacks
Medical organizations have sensitive health related documents. Unauthorized access attempts for these should not only be prevented but also detected in order to ensure correct treatment of the patients and to capture the...
A Novel Approach for Submission of Tasks to a Data Center in a Virtualized Cloud Computing Environment
The submission of tasks to a data center plays a crucial role to achieve the services like scheduling, processing in a cloud computing environment. Energy consumption of a data center must be considered for task processi...
RC4 stream cipher and possible attacks on WEP
In this paper we analyze and present some weaknesses and possible attacks on the RC4 stream cipher which were published in many journals. We review some advantages and disadvantages which come from several authors,...