A Two-Step Schedule Resource Allocation Algorithm in Cognitive OFDMA Systems

In this paper, we provide a new resource management algorithm with delay constraints in cognitive OFDMA Systems. Our objective is to give priority to the high real-time cognitive user in the allocation of the channel in the first scheduling slot, maximize multiple cognitive users' weighted rate sum by jointly adjusting their frequency and power resource, under the constraints of multiple primary users' interference powers. Let cognitive users with high delay demanding avoid to participate in the high complexity competition of the channel or easier to get more bandwidth, in which cognitive users have a bigger transmission rate. So it can be faster to access to the channel which means it cost less time to prepare to transmission or has a faster rate. The results show that you can effectively prevent the ineffective resource allocation because of the delay, thus, optimize network transmission.