Wi-Fi Sensors

Small, reliable Wi-Fi sensors with ethernet, Wi-Fi, and cellular backhaul that are easy to deploy.

BlueZoo’s Wi-Fi sensors are small, low-cost, low-power devices, each with an integrated Wi-Fi radio that listens passively for Wi-Fi probes emitted spontaneously by mobile phones.   The sensors can also be deployed as a firmware application on platforms with Wi-Fi radios.  BlueZoo’s strategy is to deploy an increasingly larger share of our sensors as firmware running on platforms like smoke detectors, security systems, smart doorbells, and HVAC controls.  

BlueZoo offers two sensor types:  One is suitable for mounting on a ceiling or wall.  Another is modular with exposed USB and SMA connectors for optional components.  Both are fanless.  


The ceiling-mount BlueZoo sensor (8″ in diameter) is white and communicates with BlueZoo cloud systems via ethernet, Wi-Fi, or cellular backhaul.  Ethernet network interface cards and Wi-Fi radios are standard.  

An optional Vodafone modem inside the enclosure provides cellular backhaul.  Data rates are low because of the efficient compression and transmission of communications.  

The enclosure with cellular modem weighs 12 ounces.

The ceiling-mount sensor is powered via PoE (802.3af) and consumes less than 5W.  PoE is an attractive for low-power devices like our sensors because running ethernet cables (cat-5, cat-5e, or cat-6) is generally far less expensive than running line-voltage wires (120v or 240v) with their attendant safety requirements.

The sensor includes an embedded omni-directional Wi-Fi antenna.

The modular sensor (2.2 x 2.2 x 0.9″) is black can be powered either via a micro-USB connector or via PoE (802.3af).  It integrates Ethernet and Wi-Fi backhaul to the cloud.  Backhaul via a cellular modem is optional.

The sensor contains an omni-directional antenna to detect probes from mobile phones, but is also available with external antenna connectors.  

A version with SMA connectors permits external antennas to be connected either directly or via a coax cable. 

External antennas are useful for two purposes. When the sensor is mounted inside a Faraday cage and the embedded antenna does not have adequate reception, an external antenna may be suitable.  

External antennas can be higher gain omni-directional antennas or can be directional antennas, useful for restricting the target detection zone of the sensor.    


Directional antennas, like the one shown to the left, typically define cone-shaped detection zones.  Common  are 90-degree detection cones.

Directional antennas allow sensors to detect people in smaller spaces, such as in front of a specific display in a store or in a corner of a restaurant.  


Wi-Fi sensors are superior to optical sensor in many applications, including when a large area (up to 30,000 sq feet) must be measured, when obstructions prevent the practical use of optical sensors, or when thousands of people must be counted.

As shown to the right, different materials impact propagation of  Wi-Fi signals to different extents.


Because Wi-Fi- and ethernet-connected BlueZoo sensors are generally deployed behind firewalls, they are inaccessible from the internet.  The BlueZoo sensors reach out to BlueZoo cloud servers over an encrypted channel to deliver data and to check for firmware updates.

BlueZoo puts a light load on backhaul connectivity, sending highly compressed data.  The volume of data will vary with the number of mobile phones in the detection zone.  

Get started today

Reach out to us — we’re here to help.

People counter sensor