Nordic Distance Measurements

[franck]

Hello, 

How much time takes the Nordic Distance Measurements in MCPD mode with IFFT on nrf52832 ?

Any limitaion on moving objects except that this measurement works well on short distance ?

Thanks 

Franck

 

[Simonr]

Hi Franck

We haven't tested a maximum on our end, but we think 10 should be possible to achieve. Did you disable high precision as well, as the "normal" precision mode should be much faster. You can also try to lower the advertising interval.

One measurement with high precision mode disabled should take ~16ms, so getting 10 measurements should in theory be possible if the delay from advertising to measurement isn't too long. Meaning you shouldn't do a bunch of other stuff over BLE as well that might increase discovery time or take up time on the radio for example.

For the measurement, there is an `nrf_dm_get_duration_us` api, that gives you the duration of the data collection for a given configuration, plus NRF_DM_PROC_EXECUTE_DURATION_OVERHEAD_US, which is the duration of the (non-high-precision) algorithms.

One try you could probably do is to run multiple rangings back-to-back and don't go via the syncing step using the advertiser/scanner, if you are interested in ranging a single device.

Best regards,

Simon

[franck]

Hello Simon, yes I'm using a nrf52832 so high precision is disabled (as not supported if I'm correct). This is great that if 10 is achievable, right now haven't managed to get more than 5-6/s

"One try you could probably do is to run multiple rangings back-to-back and don't go via the syncing step using the advertiser/scanner, if you are interested in ranging a single device."

-> this was my previous question, to get one synchronisation then call dm_request_add with same parameter everytime I get the result callback  "Is this possible to call continuously dm_request_add on both devices everytime a timeout or a sucess result is returned ??" 

Will check nrf_dm_get_duration_us api to see how long time is returned

Best regards

Franck

[Simonr]

Hi Franck

We haven't tested doing multiple rangings back-to-back without the syncing step, but our developer suggested trying this for ranging a single device.

Best regards,

Simon