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Re: only two tags range at the same time with TDMA
Posted: Sun Sep 25, 2016 1:00 pm
by justinleeyang
hi,
a issue, 26 means 480 slots, but how to calculate it?
I see the comment about "since the timer is running at ~64GHZ".
Re: only two tags range at the same time with TDMA
Posted: Sun Sep 25, 2016 1:42 pm
by arnaud
In theory you would calculate the frame frequency with 64GHz / 2^(n+m):
- n the number of bit per slot
- m the number of bit to encode the slot ID (2^m slot per frame).
And the slot frequency with 64GHz / 2^n.
The bug here is that 64e9 / 2^26 = 953Hz, the double! I have a +1 in most of these time calculation I think this is the source of the bug. 27 should have been the correct value.
By the way, is it working properly at 480Hz slot rate?
Re: only two tags range at the same time with TDMA
Posted: Mon Sep 26, 2016 2:17 am
by justinleeyang
hi, arnaud:
thanks your reply! I have understanded your method, 480 slots no problem, and I will add more tag to test.
Re: only two tags range at the same time with TDMA
Posted: Mon Sep 26, 2016 6:48 am
by arnaud
Thanks for testing! I will test as well and fix the implementation.
We are having a demo at Maker Faire Berlin at the end of the week and it is really nice to find that now: we only have 2x2m to fly autonomously and having twice as much ranging will certainly help!
Re: only two tags range at the same time with TDMA
Posted: Mon Sep 26, 2016 7:37 am
by justinleeyang
Good luck for you, and wish that I will join the Maker Faire next year.