This paper discusses the conflict that has arisen as a result of wifi and bluetooth operating on very similar bandwidths. They are close enough that they can often interfere with each other when used in closer proximity. While both experience interference as a result of this clash, bluetooth is far less succeptable. At most ranges between competing devices, bluetooth is relatively unaffected, but at ranges near 2cm severely dampens all bluetooth throughput. To get around this bluetooth has developed adaptive frequency hopping. Doing this they send test packets to detect congested frequencies and change paths to avoid collision. Wifi does not have this. But at close ranges it is a problem for both parties.
Techniques are being developed currently to allow bluetooth and wifi devices to exist in very close proximity. The most readily occurring of which was having the device, at driver level, control which was being broadcast. That way one radio device will be shut down while the other is broadcasting. This limits throughput however.
The paper did not contain a great deal of relevance to our project, as we are dealing with interactions of bluetooth devices at range, not optimizing hardware level issues. It was, however, interesting to note that bluetooth and wifi compete at all. It was a fact previously unknown to me.
http://www.edn.com/article/470440-WiFi_and_Bluetooth_fight_for_bandwidth.php
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