Abstract:
Resources available for operation in cognitive radio networks (CRN) are generally limited, making it imperative for efficient
resource allocation (RA) models to be designed for them. However, in most RA designs, a significant limiting factor to the RA’s
productivity has hitherto been mostly ignored, the fact that different users or user categories do have different delay tolerance
profiles. To address this, in this paper, an appropriate RA model for heterogeneous CRN with delay considerations is developed
and analysed. In themodel, the demands of users are first categorised and then, based on the distances of users fromthe controlling
secondary user base station and with the assumption that the users are mobile, the user demands are placed in different queues
having different service capacities and the resulting network is analysed using queueing theory. Furthermore, to achieve optimality
in the RA process, an important concept is introduced whereby some demands fromone queue aremoved to another queue where
they have a better chance of enhanced service, thereby giving rise to the possibility of an improvement in the overall performance
of the network. The performance results obtained from the analysis, particularly the blocking probability and network throughput,
show that the queueing model incorporated into the RA process can help in achieving optimality for the heterogeneous CRN with
buffered data.
