WITTRA FAQ

PRODUCT INTRODUCTION

What data do the WiTTRA Sense 360 provide?

  • Out of the box, the standard WiTTRA Sense 360 Tag includes:

    • Accelerometer – Moving/Stationary
    • Magnetometer – Magnetic orientation/compass direction
    • Gyroscope – Rotation (optional, contact Wittra)
    • Location –  Based on radio signal strength to nearest Mesh Routers, plus time-of-flight based trilateration (configurable)
    • Internal Tag temperature (which will approximately mirror the surrounding air temperature with some lag, because the Tag is sealed).
  • Wittra also has an  External Click-on Sensor (for the above Tag) which provides:

    • Ambient light level
    • External air temperature
    • Humidity
    • Air pressure.
  • The customer (via the data streamed in the cloud API) can use the sensors to derive Tilt, Fall, Shock and other movement related metrics as well as the environmental and location measurements.  

Do the sensors provide GPS coordinates?

  • The WiTTRA Sense 360 does not contain an independent GPS module.
  • The cloud portal will show the position of the WiTTRA Sense 360 on a map (with a user defined floorplan or site plan for visualization) within the network coverage area the client creates during installation. The coordinates are available from the cloud API ( Latitude/Longitude).
  • GPS technology is not a competitor to Wittra.  GPS offers outdoor positioning only whereas Wittra offers out and indoor positioning, plus a large range of sensor data.
  • GPS is of course a global location system for outdoor use, however it comes with high costs and high current consumption. If you are looking to monitor and track an asset indoors, GPS is not a fit[WT1] [MOU2] . GPS does not work reliably in buildings, areas of high interference, indoor/outdoor transitions etc., whereas the Wittra solution covers all environments in one technology deployment.

What does the software look like and how does it interact with the system?

  • The Wittra Management platform allows users to securely onboard and mange network and sensor devices, visualise position and sensor data, troubleshoot the system and set up APIs for export of data.
  • Alerts and notifications can be customized to your needs and are based on:

    • Interval = by time
    • Event based = by defined event (e.g. How long is something moving).
  • API Integrations allow data export (push data to a  third party URL or REST API queries).
  • Go to www.console.wittra.se

How easy is the system to set up? 

  • Very easy, most initial setups can be up and running within a few hours, and easily expanded within a few days.
  • The process is easy and straightforward if you follow the published guidelines. There are extensive instructions online in the Wittra portal, as well as videos available.
  • Go to https://docs.wittra.io

What is the reliability of the system? Are there intermittent failures? 

  • This is the strength of the Wittra technology.  When properly installed it is extremely reliable. The Radio Mesh technology used in the Wittra network means that the system is continuously looking for the best signal path from the WiTTRA Sense 360 to the Gateway. This allows it to overcome interference, radio black spots and dynamically changing environments.
  • The reliability usually comes down to how well the network is planned and installed:

    • Use the setup tool in the portal to check the quality of each radio link in the mesh.
    • Make sure the Mesh Routers have a permanent power source.
    • Make sure the gateway has a reliable Mains power source, and a solid Ethernet connection to the internet.
TECHNOLOGY

What is Wittra’s core technology?

  • We use  6LowPAN (6LoWPAN is an acronym for IPv6 over Low -Power Wireless Personal Area Networks.)  This is a Sub GHz radio mesh radio network. We choose sub-GHz to allow for long signal hops, low power consumption, and good penetration through building structures.
  • The Wittra Mesh Routers will form the mesh network. The Wittra network is self-forming and self-healing (if one router fails, the network will reroute the signal to another WiTTRA Sense 360).  This eliminates challenges with lost data packets. 
  • Wittra also employs frequency hopping as a robust solution against interference. Each device will listen to a channel before communicating;  if the channel has interference, the device will find a clear channel instead. This can be considered a “polite” solution to allow other users in these bands.
  • Future proof architecture allows for over-the-air firmware updates as the technology moves forward. 

What is the Range of a Wittra network? 

  • Range is dependent on placement within the environment and the type of environment. Adding more routers and gateways can increase range significantly, as well as ensuring that Mesh Routers are installed at least 2 metres above ground level.
  • You should be able to achieve  approximately 500m radius for the Gateway, and 300m per Mesh Router in open air, with line of sight between the devices.
  • When devices are installed indoors it is then a question of how many walls or floors there are in the direct path from WiTTRA Sense 360 to one or more Mesh Routers that will determine achievable distance. Every object the radio wave passes through attenuates the signal a little. Large metallic objects block the signal, so this should be taken into account during installation.
  • If the positioning feature is required then we recommend Mesh Routers are spaced every 30 to 100 metres horizontally in a grid pattern, if possible. Vertically, you can expect reliable connection through 2 floors of reinforced concrete.
  • Currently our positioning is only in 2D (per floor level). For 3D positioning it is recommended that the UWB Click-on module is used on Mesh Routers and Sense 360 Tags.

Does the position of the Mesh Router matter?

  • Yes the position of the Mesh Routers is important, especially if the use case is asset tracking (positioning).
  • Ideally the Mesh Routers are actually installed around the boundaries of the area or zone where positioning needs to be done. This will give the most accurate results in the calculated position of the WiTTRA Sense 360 relative to the (minimum of three) Mesh Routers.
  • If the distance between Mesh Routers is more than about 30 metres indoors (due to being placed around the zone boundaries) we would recommend one or more additional mesh routers are placed towards the middle of the zone (if positioning is required).

Can you package the Gateway to attain a higher IP rating (currently IP51)?

  • Yes the Gateway can be fitted with a waterproof antenna connector as a factory option.
  • An antenna cable can be used in theory; however due to FCC rules about preventing customers from using high gain antennas we cannot explicitly allow this option in North America.

What is the operating voltage and power consumption?

  • The Gateway uses a 12-Volt DC power supply (included in the kit). Current consumption is about 1 Amp, depending on what tasks the Gateway is doing.
  • The Mesh Routers require an Input power during charge: 5V, 100mA. Average current consumption during normal operation: 8mA

Can you track an asset sensor if it has left the network area?

  • Not at this point in time. This is a forthcoming functionality later this year that will include a few options:

    • The ability to cover a much wider area (using MIOTY).
    • A GPS module which can offload position data through the MIOTY network (available through third party vendors, see the Mioty Alliance website).

Can you track assets that are mobile?

  • Yes we can position mobile assets within the site boundaries. We do not market this as a true RTLS (Real Time Location System) since we do not update the position in real time; however we can provide location updates down to 20 second intervals, depending on how many mobile tags are in the network.
  • Of course frequent position updates will affect achievable battery run-time (after which the WiTTRA Sense 360 battery will need charging via the micro-USB interface). Alternatively, a plug-in external battery pack can be used to triple the capacity of the on-board battery.

How accurate is the positioning?

  • Wittra can deliver positioning accuracy of less than 1 metre, depending on the device and system configuration and site conditions. Using only sub-GHz mesh you can expect 1 – 7 metres, and with the UWB click-on you can achieve 0.5 metres accuracy.
  • That is one of the functions of the Mesh Routers / Positioning Beacons (included in the kit). A WiTTRA Sense 360 needs to be able to communicate with a minimum of three Mesh Routers or Positioning Beacons to enable the positioning function to work with good accuracy.
  • hat is one of the functions of the Mesh Routers (included in the kit). A WiTTRA Sense 360 needs to be able to communicate with a minimum of three mesh routers to enable the positioning function to work with a high degree of accuracy (<1m)
  • Thus for such a use case, proper site planning is important, in terms of ensuring correct Mesh Router / Positioning Beacon placement to achieve proper coverage for accurate positioning.

How is positioning calculated?

  • There are two approaches to positioning:

    • RSSI (Received Signal Strength Indicator) - signal strength from tag to 3 or more mesh routers. 
    • TOF (Time of Flight) – This is a significant step-up from signal strength.  This will measure the time the radio signal takes from tag to mesh router. The benefit is a less dense network is required for positioning (i.e. greater distance between Mesh Routers).

Would each remote site need additional extenders/repeaters to track assets at each location?

  • Yes, each site requires its own set of Gateways and routers. However, once a tag enters the new location (site), it begins sending data automatically, provided it has a valid PAN ID.  The new site gateway will recognize and register the tag seamlessly, similar to a “roaming” capability.
OPERATIONAL NOTES

What is the level of support available?

  • First level sales, marketing and technical support will be provided on CET (9AM-5PM CET).  Product and Technical escalations will require approximately 24 hours for response from the European HQ.
  • However, end customers will typically use an SI (System Integrator) or platform provider so primary support would come from them.
  • We remain responsible for all aspects of our hardware and APIs giving support to SI and platform providers.
  • Wittra also offers expanded technical support plans based on the size of client deployment.

Do all products have the proper up-to-date standards and certifications required for North America?

  • Yes, most products are FCC certified for operation within North America (USA and Canada).