Varying handover parameters at a specific cell edge and observing the effects of this in order to locate a coverage hole

摘要

A cell edge coverage hole detection method based on collecting (S10) radio link failure, RLF, statistics provided by multiple UE reports at the handover stage. At a cell edge, the handover point varies for each UE due to the differences in parameter settings and measurement values, giving a statistical distribution of the exact handover point. In the method, RLF reports are grouped by connectivity pattern and a specific cell edge is identified for closer investigation (S20). Hysteresis and/or offsets are varied for UEs at the cell edge (handover parameters are varied) and subsequent RLF reports are monitored for changes in tendencies of event sequences (S30). If RLF persists for most of the UEs, the method infers from this (S40, S60) the existence of a coverage hole. In LTE, the requirement for accurate UE location information is optional in the latest releases and therefore the invention aims to provide an automated coverage hole detection method which does not rely on location information. [Fig.13]