Spectrum Map Empowered Resource Management for QoS Guarantees in Multi-Tier Cellular Networks

Deploying picocells overlaying Macrocells as the second tier has been regarded as a promising approach to enhance the spectrum efficiency and thus high data rate services, but only if cross-tier interference can be effectively controlled. Since both tiers shall support considerable numbers of users, interference mitigation by centralized/collaborated radio resource allocation among two tiers is infeasible. The cognitive radio is consequently a potential technology for autonomous interference mitigation. However, the obstacle of applying cognitive radio to the picocell is an unacceptable amount of feedback of channel sensing results from users. To tackle this critical challenge, we propose the spectrum map resource management (SMRM) for picocells. By compressive sensing, the SMRM constructs the spectrum map indicating the radio resource availability on any given location by only leveraging a small portion of users to perform channel sensing. Through the concept of effective capacity, the SMRM then controls available resource of the picocell to practice the critical guarantees of quality-of-service in picocells, and thus future multi-tier cellular networks.