Dynamic spectrum access for multi-radio access technology, multi-operator autonomous small cell communication systems

The autonomous deployment of small Access Points (APs), commonly referred to as small cells, provides an economically feasible network densification solution to increase the capacity of cellular communication systems. However, having a small number of users with a single operator and typically employing a single Radio Access Technology (RAT) results in suboptimal spectrum utilization at small cells. To improve the performance and spectrum utilization at small cells, this paper presents a Dynamic Spectrum Access (DSA) framework that provides small cells with secondary access to spectrum primarily assigned to other RATs and operators. To avoid the shortcomings of spectrum sensing, APs broadcast spectrum occupancy information to facilitate secondary spectrum access. System-level simulations, performed for a setup of two operators employing two RATs, show substantial performance gains when implementing the proposed DSA framework.