1,585 research outputs found
Cross Layer Aware Adaptive MAC based on Knowledge Based Reasoning for Cognitive Radio Computer Networks
In this paper we are proposing a new concept in MAC layer protocol design for
Cognitive radio by combining information held by physical layer and MAC layer
with analytical engine based on knowledge based reasoning approach. In the
proposed system a cross layer information regarding signal to interference and
noise ratio (SINR) and received power are analyzed with help of knowledge based
reasoning system to determine minimum power to transmit and size of contention
window, to minimize backoff, collision, save power and drop packets. The
performance analysis of the proposed protocol indicates improvement in power
saving, lowering backoff and significant decrease in number of drop packets.
The simulation environment was implement using OMNET++ discrete simulation tool
with Mobilty framework and MiXiM simulation library.Comment: 8 page
Medium Access Control Protocols for Ad-Hoc Wireless Networks: A Survey
Studies of ad hoc wireless networks are a relatively new field gaining more popularity for various new applications. In these networks, the Medium Access Control (MAC) protocols are responsible for coordinating the access from active nodes. These protocols are of significant importance since the wireless communication channel is inherently prone to errors and unique problems such as the hidden-terminal problem, the exposed-terminal problem, and signal fading effects. Although a lot of research has been conducted on MAC protocols, the various issues involved have mostly been presented in isolation of each other. We therefore make an attempt to present a comprehensive survey of major schemes, integrating various related issues and challenges with a view to providing a big-picture outlook to this vast area. We present a classification of MAC protocols and their brief description, based on their operating principles and underlying features. In conclusion, we present a brief summary of key ideas and a general direction for future work
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