User's Manual

Document MV0319P.N
© Xsens Technologies B.V.
MVN User Manual
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MTw's across the wireless network to within 10 microseconds, achieving 'wired like' system
performance. The Awinda protocol is developed such that no data is ever lost. If individual packets are
missed, there is some room to contain data temporarily. This buffered data is then retransmitted. If these
packets become lost (for example if the subject wearing the hardware is outside of the radio transmission
range and for a prolonged period – meaning the buffer becomes full) then it is still possible to retrace
the missing data due to the use of SDI. Retransmitted data is used during reprocessing, for this reason
Awinda data can appear better – smoother and more accurate after reprocessing.
19.12.1 Choosing a Radio Channel for MVN Awinda
Figure 69: Overview of channels operating around 2.4GHz; for ease of channel selection
Figure 69 provides an overview of the allowed channels for operating MVN Awinda. The Awinda protocol is based
on the IEEE 802.15.4, around 2.4 GHz. The bottom row of the figure shows the channels on the 2.4GHz, the top
row shows how WiFi channels use the spectrum. This should indicate to the user that the best channels to use
when you know which channel WiFi is on. When in an environment where WiFi is also expected to be in prevalent
use, but you are not sure which channels, try Channels 11, 15, 20 or 25. Bluetooth uses the entire spectrum
around 2.4 GHz, but will (try to) avoid channels in use by other systems including Awinda channels.