Good afternoon Leo, how are you?
I am developing a project with the DW1000, when they are stopped they communicate perfectly.
However, when I put the module inside the vehicle and ride the vehicle around 20km / h the modules do not communicate, they lose package.
Do you know the best setting for modules to communicate at speeds above 20km / h?
thank you
Hi Pedro,
I’m not aware of your radio configuration (Datarate, Channel, PRF , Preamable etcc), so please have a look at the white papet attached.
I also advice you to read the IC user manaual section 9.5 Node density and air utilisation and APS016.
In general , one should use high datarate (6.8Mb/s or 850Mb/s) , a frequency (update rate) matching the requirement. (Eg 20km/h is 5.6m/s. So 10 hz gives you an update every ~0.6m)
TB001 Max DW1000 Speed.pdf (195.7 KB)
Regards
Leo
One other thing to take into account, if you are using TWR then when is the range actually measured? If calculating position based on TWR to a number of fixed points then keep in mind that you could well have moved between the measurements.
If you use TDoA then this problem goes away.
I’ve not had any issues with speeds over 100 km/h. As DecaLeo said we are using high data rates and doing everything else possible to keep packet times to a minimum. If nothing else this decreases the distance you move during the ranging process and helps keep errors and uncertainties to a minimum.
Using double sided two way ranging (DS-TWR), the position reported is the average position of when the 3 packets are sent. For example, if a tag moves 10 cm between first and last packet, and the turn around times are symmetric, then the reported position will be a 5 cm shift from first packet position.
High bit rates and short preambles increase speed tolerance well above typical needs. You can make it work even up to jet airliner speeds if you want, but there’s no practical need for that.
Using short turn around times reduces the movement between packets and also reduces the clock drift errors, so good all around.
Mike Ciholas, President, Ciholas, Inc
3700 Bell Road, Newburgh, IN 47630 USA
mikec@ciholas.com
+1 812 962 9408