Inter-System Handover and Coverage Detection for 3G/WLAN Cooperation-Invited Paper-

摘要

Future wireless communication systems willfeature by a high degree of interoperability for whichsystem integration is commonly regarded as an importantaspect. To allow for smooth network migration, VerticalHandover (VHO) thereby is one of the key enablingtechnologies. Within this paper, VHO simulations arepresented and analytically verified to demonstratemaintenance of services in a patchy WLAN environment.To allow for optimized VHO triggering, an intelligentconcept referred to as Hybrid Information System ispresented. Anyway, prior to taking sophisticated handoverdecisions, knowledge on alternatively available systemsneeds to be present. This entails the initial detection ofcomplementary systems, which directs the systemintegration aspect to the problem of coverage detection.The present paper copes with this problem by proposing anew algorithm, referred to as Centre of Gravity. Thealgorithm evaluates densities of location relatedmeasurement reports whereby special attention is put oninherent positioning errors.