Why does the BlipTrack™ Bluetooth sensor have 3 radios?
By using 3 antennas, of which 2 points in each direction along the road and the third is a round emitting antenna, we are able to detect when queue is building up in a single point. This is done as a combination of checking the vehicles time spend in the coverage area combined with the vehicles direction, which is detected by the 2 directional antennas.
Queue Warning done by a single Bluetooth sensor
If the Bluetooth sensor is having only one radio you are not able to detect driving direction in the point and you would not know in which direction the queue is building up.
Queue warning can then be done by using 2 sensors, but that’s more expensive and the response time will be slower.
Higher detection rate
By using 3 radios there are 3 times as high chance for detecting a Bluetooth device, it’s as simple as that. And by having 2 directional antennas and one omnidirectional antenna, we are covering an area more than 3 times as large as a single radio solution.
This means we have the vehicles within range more than 3 times as long and our chances of detecting a Bluetooth device is more than 3 times higher, compared to a single radio solution.
A combination of the two above arguments results in BlipTrack™ Bluetooth Traffic sensors having an unmatched performance when it comes to detection rates, compared to single radio solutions, where detection rates can be as low as 50%. In fact our detection rate at Highways is as high as 96% of the measurable devices and in areas with slower traffic, we are close to 100% of the discoverable Bluetooth devices.
Especially in Origin/Destinations analysis, a high detection rate is desirable: Experience shows that app. 25% of all vehicles have a Bluetooth device that can be detected. If you Bluetooth sensor only detects 50% of these, your penetration figure will be 12,5% and the traffic splits up in 2 directions with a 60/40 split, now your penetration figure will be 7,5% and 5% and the next sensor will pick up 50% which means 3,75% and 2,5%. Soon you Origin/Destination analysis will lose its credibility.
