I'm doing a project on college bus management. Whenever the bus is at a minimum distance of 5 km(say) away from the student whom the bus has to pickup, it should send him an alert message that the bus will reach his stop with in few minutes so that the student becomes aware of the bus coming and wouldn't miss the bus. This also saves time of students who wait for long for the bus. So I need information regarding the sensor that detects the registered users within the range of 5 km(say) and sends them an alert message.
This document was generated from the following discussion: Range detecting sensors