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Comment by anitil | Hacker News Reader

I'm surprised that these things transmit at around 1Hz, I thought it'd be on the order of every 10 seconds to a minute. Given that I assume a lot of beacon devices are running on a coin cell battery I would have thought it would be slower. Or is that particular only to this device?

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1hz seems slow to me. A company that I worked at was designing robust industrial, apple airtag/tiles with a specific application 8 or 9 years ago.

BLE operates on a very crowded frequency. WiFi, Bluetooth, etc are all on the same frequency and spamming out thousands of packets constantly.

We had to triple our broadcast frequency and period in order to reliably detect a beacon within 5 seconds of a phone being in range.

We settled on 200ms frequency and broadcast for 15ms.

Our decide had a 10 year battery life on a couple coin batteries…

I find it very intriguing you landed on 200ms, considering the default beacon rate of the majority of WiFi access points is 100ms. Clients do not like going much longer before you start dropping beacons and discoverability tanks... which is shown in your results. Genuinely fascinating.

That answers my question perfectly, thankyou!

>We had to triple our broadcast frequency

What do you mean by this ?

I think they meant triple how often they broadcast, not using a radio frequency x3 higher on the spectrum.

1 Hz is slow. Apple's iBeacon standard specifies 10 Hz, for instance. Also, every packet is transmitted on three different channels, so there is actually quite a lot of traffic generated.

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