A comparison of MIMO system with a SIMO reveals that the MIMO system need

In this paper, we present a novel and computationally efficient water filling algorithm for multiuser in cognitive radio network (CRN). This algorithm is based on the multiuser water filling theorem and persuades the subcarrier allocation for a multiple access system. This approach exaggerates the total bit rate under the constraints of user-individual power budgets. Acquiring Energy Efficiency (EE) is very troublesome for wireless communication systems exclusively for CRN. The analysis here is with the mean EE maximization problem for secondary user (SU) with both primary user (PU) and SUs. The solution to the problem starts by examining both the peak and mean transmit power constraints for the SUs and outage probability constraint for the PUs. The problem here is nontrivial. The results attest that the efficiency of the system is enhanced with the proposed water filling algorithm and also it has been observed that the outage probability is reduced. Further, there is enhancement in the capacity of a MIMO system.