Manual

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7. Advanced system settings and optimization
Start using advanced settings only when you know what you are doing
If you ran into troubles, connect the beacon or modem to the PC via USB and
use the DEFAULT button. It will upload “factory settings” to the board while
keeping the device address untracked
7.1 How to place beacons
Avoid placing beacons on long sound-conducting objects
This is a very rare but may happen in some special circumstances.
The best practice is to place beacons (stationary and mobile) in places that would
not result in the transfer of ultrasound energy from the beacon’s board/case
directly to the place it is attached via a medium other than air. For example, solid
attachment of a beacon to a long horizontal metal tube may result in the following:
• Sound emitted from the beacon propagates directly to the metal tube.
• Propagation losses inside metal are much smaller than in the air
Moreover, the tube may act as a low-loss waveguide.
• If the tube is solid enough and long enough, there may be a weird effect
where the receiving beacon receives the signal sooner than expected,
i.e., sooner than the distance divided by the speed of sound in air. That
happens because the speed of sound in metal is much higher than the
speed of sound in the air. The ultrasound signal may even look stronger
than the real signal propagated through the air due to the lower amount
of losses of ultrasonic in metal than in the air
• It is good practice to place beacons on something relatively soft or
something that does not conduct sound
Place beacons in a way that provides the proper ultrasonic coverage. It
must be one beacon in the line of sight of minimum 2 beacons. Try to locate
them under ceilings to avoid shadows, walls etc.
• Optimal settings for stationary beacons in small and big rooms
Use 30–50 ultrasonic pulses for larger places and the default 5 pulses for
smaller places.
• Optimal settings for noisy environment