Implementation of a channel selection algorithm using cognitive radios

Abstract

With the increase of wireless devices, the wireless spectrum is becoming overloaded causing users to experience delays and performance degradation. Typically, a device will start transmitting data on a frequency and continue transmitting on that frequency regardless of the channel being overloaded or not. Some smarter devices such as routers are able to sense when their channel is becoming overloaded by observing delays and amount of devices transmitting on that frequency. Spectrum analyzers are usually very expensive and usually do not provide many functionalities other than analysis. Utilizing newer alternatives for sensing the spectrum such as Software Defined Radios (SDR) can address frequency allocation problems and allow users to decide the best frequency to use for communication. A promising SDR such as GNU Radio will be covered in this thesis, as well as the hardware components needed for its functionality. In this thesis, a cognitive radio approach is taken in designing a channel selection algorithm by scanning and monitoring the wireless spectrum on IEEE 802.11 b/g through the use of GNU Radio and USRP. Tests are performed as a proof of concept and to help future research with the use of cognitive radios.