Design and implementation of a hardware-constrained Cognitive radio MAC protocol

Cognitive radio (CR) is a new wireless communication method that can sense local spare spectra. Then it communicates with each other using sensed available spare spectra. In a CR network, a medium access control (MAC) layer configuration determines a common set of channels to facilitate communication among participating nodes. Because spare spectra change dynamically according to time and locations, available spare channels of the number and the identity of each node are changing any time in a multi-hop network consisting of CR nodes. In this paper, we present a novel dynamic hop reservation multiple access protocol based on the original one. Moreover, the MAC system is designed using Verilog HDL and implemented using ALTERA Excalibur ARM EPXA4F672C3 (FPGA). It can access and quit channels efficiently without any common channel.