Inter-System Handover Parameter Auto-Tuning in a Joint-RRM Scenario

In this paper, an auto-tuning scheme based on a fuzzy logic controller (FLC) is proposed for a standard inter-system handover (IS-HO) algorithm. A heterogeneous network scenario is considered, comprising GSM and UMTS radio access technologies. FLC modifies IS-HO parameters to perform load sharing between technologies based on network congestion statistics. To validate the proposed scheme, a system-level simulator with a joint radio resource management (JRRM) module has been developed. FLC adaptation capabilities are checked through changes in the time-space traffic distribution in a realistic scenario. Results show that call blocking rates can be significantly reduced, while keeping connection quality almost unaltered, at the expense of increasing network signaling load.