For further information about monitorization of shopping and street activity, please read the "Smartphone detection" section in the Meshlium datasheet:
For further information about vehicle traffic monitoring, please read the "Smartphone detection" section in the Meshlium datasheet:
The new Meshlium Xtreme allows to detect iPhone and Android devices and in general any device which works with WiFi or Bluetooth interfaces.
These devices can be detected without the need of being connected to an specific Access Point, enabling the detection of any Smartphone, laptop or handsfree device which comes into the coverage area of Meshlium.
The idea is to be able to measure the amount of people and cars which are present in a certain point at a specific time, allowing the study of the evolution of the traffic congestion of pedestrians and vehicles.
Users have to do nothing to be detected as the WiFi and Bluetooth radios integrated in their Smartphones (Mobile, Hand and Cell Phones) periodically send a "hellow!" message telling about their presence.
The information read from each user contains:
The coverage areas may be modified by changing the power transmission of the radio interfaces allowing the creation of different scanning zones from a few meters (in order to study an specific point) to dozens of meters (to study the whole street or even the entire floor of a shopping mall).
Example of information monitored by the WiFi Scanner:
|53482||2012-04-24 09:11:26||D8:2A:7E:10:1E:63||libelium_wsn1||60||Nokia Corporation|
Example of information monitored by the Bluetooth Scanner:
|45400||2012-05-16 16:18:12||00:26:7E:5F:3C:18||myCar||-72||Handsfree||PARROT SA|
|78005||2012-04-20 12:59:27||D8:2A:7E:0E:C3:10||Tropic||-85||Smartphone||Nokia Corporation|
Applications related to Shopping and Street activities:
The Vehicle Traffic Monitoring is also another important application as understanding the flow and congestion of vehicular traffic is essential for efficient road systems in cities. Smooth vehicle flows reduce journey times, reduce emissions and save energy. Similarly the efficient flow of pedestrians in an airport, stadium or shopping centre saves time and can make the difference between a good and a bad visit. Monitoring traffic - whether road vehicles or people - is useful for operators of roads, attractions and transport hubs.
Applications for Vehicle Traffic Detection:
The monitoring system can also be used to calculate the average speed of the vehicles which transit over a roadway by taking the time mark at two different points.
Do the users need to have an specific app installed or interact somehow to be detected?
No, the scan is performed silently, Meshlium just detects the "beacon frames" originated by the WiFi and Bluetooth radios integrated in the Smartphones. Users just need to have at least one of the two wireless interfaces turned on.
How do we differentiate if the Bluetooth device detected is a car’s hands-free or an Smartphone?
In the scanning process each Bluetooth device gives its “Class of Device” (CoD) attribute which allows to identify the type of service it gives. We can differentiate easily the CoD’s generated by the car’s handsfree from the people’s phone ones.
How do I control the inquiry area?
In the Bluetooth inquiry there are seven different power levels which go from -27dBm to +3dBm in order to set different coverage zones from 10 to 50m. In both WiFi and Bluetooth radios these zones can also be increased or decreased by using a different antenna for the module as it counts with an standard N-Male connector. The default antenna which comes with the scanning modules is an omnidirectional antenna with a gain of 5dBi.
How do I calculate the distance of any of the devices detected?
In the inquiry process we receive the MAC address of the Bluetooth device along with the Received Signal Strength Indicator (RSSI) which gives us the quality of the transmission with each device. RSSI values usually go from -40dBm (nearest nodes) to -90dBm (farthest ones). In the tests performed devices at a distance of 10m reported -50dBm as average, while the ones situated at 50m gave us an average of -75dBm.
What about privacy?
The anonymous nature of this technique is due to the use of MAC addresses as identifiers. MAC addresses are not associated with any specific user account or mobile phone number not even to any specific vehicle. Additionally, the “inquiry mode” (visibility) can be turned off so people have always chosen if their device will or won't be detectable.
How do the Bluetooth, WiFi and ZigBee radios coexist without causing interferences with each other?
WiFi, ZigBee and Bluetooth work in the 2.4GHz frequency band (2.400 - 2.480MHz), however, the Bluetooth radio integrated in Meshlium uses an algorithm called Adaptive Frequency Hopping (AFH) which improves the common algorithm used by Bluetooth (FHSS) and enables the Bluetooth radio to dynamically identify channels already in use by ZigBee and WiFi devices and to avoid them.