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Broadcom Chips To Enable Packet Traffic Arbitration for 2.4GHz Co-Existence. The problem is what you could call intra-device interference, i.e. that experienced by devices that host more than one radio. The typical example in consumer electronics would be devices that support both WiFi and Bluetooth. PTA is a recommendation, not a standard, so implementations vary in the details of how to use PTA. The most common form of it uses 3 signals, usually called REQUEST, PRIORITY and GRANT.