Abstract: In this paper an approach is proposed considering the Transmission Rate Adaptation for all 802.11 supporting a collection of transmission rates with reliable decoding of a higher rate demands at higher link quality for power optimized communication. Recent advances in physical layer technologies, e.g., ultra wideband (UWB), multiple-input and multiple-output (MIMO), and cognitive radio (CR), have made profound impact on wireless networks. In this work, CR is considered which a revolution in radio technology is. CR is enabled by recent advances in RF design, signal processing, and communication software.

Keywords: Wireless Network, Cognitive Radio, Network Layer, Link Layer, Physical Layer, BER, SNR.