Guided tour of handoff steering for bandwidth in indoor venues

With the advancement and development for more than two decades, WiFi has become an indispensable infrastructure in most of indoor venues. Indoor localization using this pre-existing infrastructure has been studied in the literature and is proven practically feasible, which mostly relies on WiFi fingerprints and the corresponding radiomap database. Since the radiomap essentially tells which APs are available and how strong their signals are at positions in the venue, this information can usefully utilized to 'steer' to a better AP for the purpose of increasing the user throughput, which we call Guided Tour of Handoff Steering (GUT) in this paper. This steering is not much different from a conventional handoff, but it does not need an expensive scanning process owing to the radiomap, thus some additional handoffs are allowed than conventional handoffs. This leads to higher throughput, because a client can switch to a better AP whenever available. Based on an extensive experiment in a large-scale indoor venue of 119,685m2 with 1,734 APs, it is observed that GUT achieves as much as 84% higher throughput, but the number of handoffs increases only a few. This result supports that the handoff steering is not as expensive as the conventional handoff in terms of latency and traffic.