**4.1 Bus navigation using embedded Wi-Fi and a smartphone application**

Urban Bus Navigator (UBN) is a system infrastructure that connects passengers' mobile smartphones with Wi-Fi-enabled busses, gaining real-time information about the journey and transport situations of passengers [4]. A key feature of UBN is a semantic bus ride detection that identifies the concrete bus and route the passenger is riding on, providing continuous, just-in-time dynamic rerouting and end-to-end guidance for bus passengers. Technical tests indicate the feasibility of semantic bus ride detection, while user tests revealed recommendations for effective user support with micro-navigation. The system elements include semantic bus ride detection using a Wi-Fi-based recognition system and a dynamic trip tracking. The semantic bus ride detection combined with the phone's GPS is used to monitor the passenger's trip progress. Deviations are immediately recognized and trigger replanning the trip, resulting a new set of navigation instructions for the passenger. The architecture is composed of Wi-Fi for proximity detection of busses by the passenger's mobile phone, a smartphone application for trip planning using macronavigation, a context-aware trip hints using micro-navigation, context sensing, bus ride recognition, and trip tracking.
