can i scan 10000 beacons having advertising interval 10 secon

[Nag]

Hi,

is it possible to scan 10000 beacon having adv interval of 10 seconds. is their any maths or formul we can do ?

i have set nrf52 to scan continuesly,   

[run_ar]

Hi,

If we had perfect randomization this would be plausible. However the advertisements are not perfectly random so not sure if 10000 beacons would work. In addition the scanner does not scan for 100% of the time as it would need some time to process the packets.

The easiest model would be to calculate the on air time of the packet you would like to transmit. i.e. 240µs for 30 bytes. Assume perfect randomization and 100% scanning and calculate the probability of receiving the packets based on that. This will give you the best case scenario, so you can see if its plausible.

[Nag]

i am using ready made beacon from third party, which again is using nrf, i can't control transmit time.

what if i scan for 30 minutes, though beacon will advertise at 10 seconds . is their any chance with some logic that i would be able to get all cards, i don't have to capture all advertisement but just have to  get atleast one  once from each beacon in 30 minutes

[run_ar]

So as I said. Calculation based on a perfect randomization of advertisement packets shows that this is plausible. However this is the best case. Unfortunately, there is no way of guaranteeing you will receive packets from all the advertiser. You could increase your chances if you have three scanners, one for each channel. I also assume you won't have active scanners, only passive and no scan responses.

What is the use case for this? What is the density of these advertisers, are they all within close proximity of each other?

[Nag]

yes, we are going track asset which will me more than 20k with in area of 500 meter. though we will try to reduce congestion by lowering power of beacon and our observer. i think it can only be known practically, but just was trying to solve it therotically before going for so huge

[run_ar]

500meter is a long distance. If I assume perfect randomization and 20 000 units in close proximity, 10 second advertisement interval, the probability of receiving a successful 30byte packet is ~61.9% (78.7% with 10k units). With 20 re-transmits it's  almost 100% probability of receiving a packet from each advertiser using a perfect scanner.

In your advantage you have a large area so you will not have all the 20k units nearby, probably not 10k either.

In your disadvantage you do not have perfect randomization, and you do not have a 100% duty cycle scanner. But I would say this is plausible and that you should try. And it would be interesting to get a report on your findings.

[Nag]

ok thanks, its great, will surely go forward will let all know the result