Transmission Protocol Design in Cognitive Cellular Heterogeneous Networks
Yinglei Teng, Ying Wang, Ya’nan Xiao, Mei Na Song · 2016
The cellular heterogeneous networks (CHNs) are of great interest for the great potential of improving the network capacity by employing low-power, easy- deployment short-range mini-base stations (BSs). To cope with the challenge of inter-layer/inner-layer interference environment in such heterogeneous architecture, we introduce cognitive Radio (CR) in CHNs, and named it as CR Enabled cellular heterogeneous networks (CCHNs). However, the transmission protocol deign is crucial for the implement of CCHSs. For one thing, the division of sensing and access phase is vital for the sensing accuracy and spectrum efficiency; For another, the power spend on the spectrum sensing cuts the transmission power allocation budget. In this paper, such coupled problem is solved by a Bi-level optimization method, by which the joint problem is decoupled to the upper level power allocation subproblem and lower level slot partition subproblem. Simulation results show that the proposed algorithm achieves the optimal jointing optimization of spectrum sensing and access, which alleviates the inter-layer interference between heterogeneous cells and improve the performance of entire network.