the Decawave DW1000 datasheet rev. 2.18 has on the front page
“Extended communications range up to 290 m @ 110 kbps 10% PER minimises required infrastructure in RTLS”
And the DWM1001Dev System overview states
"The DWM1001 range is up to 60 meters (point to point) for the best antenna orientation and with ideal line of sight conditions.
Our initial experiments with DWM1000 give OATS range of around 60m for blink messages with acceptable SNR.
Nothing like the 200+ meters claimed by the chip datasheet
Can anybody explain the discrepancy?
The key point is the @ 110 kbps.
If you want lots of range then you either need to run at a lower data rate or a higher transmit power.
Assuming your power is fixed by the regulatory requirements then there are a number of different things you can do to increase range, other than changing the antenna they all come at a cost of decreased throughput. Data rate is the simplest and most effective one of these options.
A higher gain antenna means you need to drop the transmit power but the extra sensitivity on the receive side does buy you some range.
The Channel used will also influence the range with CH2 being superior to CH5 (dwm1001) for example.
Is the channel dependency purely due to antenna gains and free space path loss at the different frequencies or is there some other effect coming into play?
Good answer. Been reading around since I posted, and can’t fault the logic.
It turns out that the DWM1000 has a default TX (really low) power setting, not the recommended one, nor can I find a pre-tested calibration figure for the module. Given that the antenna is already attached and that TX power calibration requires specialist equipment, that is a little bit disappointing.
Perhaps Decawave have an appnote showing nominal ranges at a variety of (legal) settings for the DWM modules? Would save an awful lot of repetitious testing…
I think the answer to channel dependency is (mostly) in APS017 “Maximising Range in DW1000 based systems.”
Hope that helps.