Users Scheduling and Power Allocation Algorithm for MIMO-OFDMA Green Cognitive Radio Systems

With growing of wireless systems integration, the role that plays green communication platforms are becoming more essential for reducing energy consumption. By proposing a based sub-optimal green energy-efficient algorithm to solve issue of low computational, this paper investigates the effect of users scheduling and power allocation scheme for MIMO-OFDMA green cognitive radio network The problem is formulated as a mixed-integer non-convex optimization problem, in which the objective is to maximize the energy efficiency, enabling Green Communication, under the constraints of the per-user power budget and primary system’s QoS requirements. Taking account of the mixed-integer and non-convexity nature of the problem, we propose a sub-optimal energy-efficient algorithm through two successive steps. The first step schedules the subcarriers among the SUs based on IA while the second step iteratively allocates the power based on Dinkelbach’s method. Through numerical result, the proposed algorithm is revealed to achieve significant improvement in the energy efficiency compared to the traditional spectrum-efficient algorithm.