Control region protection in LTE-A networks

The protection of downlink control signals in an LTE-Advanced (LTE-A) system is the objective of this paper. For this purpose, we develop a method, known as dynamic and autonomous control region assignment (DACRA), which is applicable to uncoordinated and (possibly) dense wireless networks. The proposed method mainly exploits the carrier aggregation and cross-carrier scheduling properties inherent to LTE-A networks. It is designed such that each base station (BS) proactively protects the control signals reserved for its own user equipments (UEs). Additionally, the interference protection does not coincide with an intolerable and unnecessary reduction in the attainable spatial reuse of radio resources. This is achieved by smartly defining two classes of resources depending on their foreseen usage by a BS and assigning them to different use cases according to the prevailing interference conditions. The effectiveness of our proposal is corroborated via systemlevel simulations which reveal that outage ratios of UEs are significantly decreased without increasing the complexity at UEs and BSs.