Multivariable algorithm for dynamic channel selection in cognitive radio networks

Abstract

The spectral handoff is important in cognitive wireless networks to ensure an adequate quality of service and performance for secondary user communications. This work presents a multivariable algorithm for dynamic channel selection used in cognitive wireless networks. The channel selection is based on the fuzzy analytical hierarchical process (FAHP) method. The selected criteria for choosing the best backup channel are probability of channel availability, estimated channel time availability, signal to noise plus interference ratio, and bandwidth. These criteria are determined by means of a customized Delphi Method and using the FAHP technique; the corresponding weight and significance is calculated for two applications classified as best effort (BE) and real time (RT). The insertion of the fuzzy logic in the AHP algorithm allows better handling of inaccurate information because, as shown the results, consider more options to evaluate in contrast to a conventional AHP. As a difference with related work, the performance of our proposed FAHP method was validated with captured data in experiments realized at the GSM frequency band (824-849 MHz). This is due to the challenge of finding white spaces to communicate in this frequency band. This band represents more disputes in accessing spectral opportunities than other radio frequency (RF) bands because of the high demand for mobile phone communications. The proposed FAHP algorithm has a practical computational complexity and provides an effective frequency-channel selection. This proposed FAHP algorithm presents a new methodology to select and classify the variables based on a modified version of the Delphi method. The results of the proposed method were contrasted numerically with other three methods.

Cognitive Radio-Modulation and Demodulation

“…Software radio performs the above functions at the transmitter side and is shown in figure. It identify the available transmission channels [8,12], determines the suitable channel modulation, examine the propagation path, and steers it's transmit beam in the right direction. And also, it determines the appropriate power level, and then transmits in an advanced application.…”

Time triggered handoff schemes in cognitive radio networks: A survey

“…Nevertheless, sometimes SUs with no multimedia services have to stay in a waiting queue for long durations, which increases the overall waiting time. Different from [112], the algorithm presented in [20] combines the analytical hierarchy process (AHP) [22] and technique for order of preference by similarity to ideal solution (TOPSIS) [21] to perform a handoff decision. AHP evaluates the decision criteria for the selection of best target channel while TOPSIS evaluates all available channels and arrange them from best to worst.…”

Multi Channel Selection using Distributed Mutual Exclusion and Multi-criteria Decision in Cognitive Radio Networks

“…In Hernandez et al (2015) and Drissi et al (2017), a combination between fuzzy logic and AHP method for network selection are proposed. Hernandez et al (2015) present an algorithm based on four variables which are probability of channel availability, estimated channel time availability, SNR and bandwidth. It provides an efficient method for selecting channels.…”