bluetooth - iOS: Connecting to BLE device when 20+ such devices are in the room? -



bluetooth - iOS: Connecting to BLE device when 20+ such devices are in the room? -

i'm developing ios app connects type of ble device, i'm writing code in room has 20+ such devices sitting around, powered up. consistently find in morning, can connect personal device fine, day wears on, becomes impossible connect device, if 20+ other devices have woken somehow , blocking signal. no 1 using of these devices; they're sitting on tables. known bug? apple working on it?

are devices advertising? if advertising 20ms hard hear all. there "only" 3 advertising channels share between devices. connection happens on same channels (the peripheral listens after it's own advertising hear if want connect).

it has nil apple corebluetooth. in experience corebluetooth can handle around 20 devices after connection has succeeded , activity has moved traffic channels.

1) seek using slower advertising interval. should work okay if app in foreground. 2) utilize ble sniffer (ti usb dongle fine) , see if connections fail on protocol level, not corebluetooth's fault. 3) advertise fast interval when needed or really need fast discovery.

as rule of thumb apple needs 55 advertisements in background mode see device when it's 1 visible. if need around 1.1second discovery might need 20ms advertisement interval, else utilize 100ms or more (see apple advertising interval guidelines exact number optimise discovery) 100ms gives much more capacity , not bad discovery. 1-2s gives much longer battery lifetime , found in 1-2 minutes if app in background. quite fine eyebeacons in malls or while might want 100-200ms in smaller areas.

ios bluetooth bluetooth-lowenergy

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