In this paper, we investigate the idea of using cognitive radio to reuse locally unused spectrum for communications. We consider a multiband/wideband system with two users in which the primary (licensed) user and the secondary (cognitive) user wish to communicate to the base station, subject to mutual interference. We introduce the notion of the virtual noise-threshold which represents a proxy for the primary user to allow cognitive communications. We determine, under the assumption that the primary user is oblivious to the presence of the cognitive user the acceptable interference level within a given quality of service. We also give an interesting way in the paper to acquire the primary user's side information. The proposed strategy is proved to be the optimal one that achieves the maximum rate for each of the two users under the constraint that the secondary user maintains a guarantee of service to the primary user when cognitive communication is considered.
Optimal power allocation for cognitive radio based on a virtual noise threshold
CWNETS 2007, 1st International Workshop on Cognitive Wireless Networks, August 14, 2007, Vancouver, Canada
Systèmes de Communication
© ACM, 2007. This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version was published in CWNETS 2007, 1st International Workshop on Cognitive Wireless Networks, August 14, 2007, Vancouver, Canada http://dx.doi.org/10.1145/1577382.1577386
PERMALINK : https://www.eurecom.fr/publication/2343