
Ask HN: how can WiFi captive portal web pages affect iOS hardware keyboards? - walterbell
There are many reports [1] of this unsolved issue: external iOS keyboard (bluetooth or smart connector) works until authentication to some WiFi captive portals.<p>Theoretically speaking, how is this possible? Could a wifi access point send incorrect management frames that affect the hardware chip that handles both WiFi and Bluetooth on iDevices? Why would that affect non-bluetooth keyboards that are physically attached via Smart Connector?<p>[1] https:&#x2F;&#x2F;discussions.apple.com&#x2F;thread&#x2F;8075772
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PaulHoule
2.4 GHz WiFi can interfere with Bluetooth transmissions since they use the
same frequencies. It's particularly bad when the two transceivers are located
close together or share the same antenna.

There is a bag of tricks for dealing with this such as separating
transmissions in time, cancelling out the transmitted waveform that bounces
back to the receiver (really works, enables full-duplex communication,) etc.

Certain devices might not play well with coexistence mechanisms and thus cause
problems.

