See USPTO Appl. No. 12/700,098
Photography Bay has uncovered a patent for what appears to be radio based flash triggers from Canon.
It's an obvious evolution and much needed feature in todays DSLRs.
The patent application tells us that Canon’s proposed wireless flash system is based off of the IEEE 802.15.4 standard, which is more commonly known as a wireless standard applied for low-rate wireless personal area networks operating at 2.4GHz, 915MHz and 868MHz. The 802.15.4 standard is the basis for the likes of the ZigBee specification, which these little chip antennas use to garner an impressive range of 300 feet (using the 2.4GHz band).
This is not a whole lot different in concept from the good ole 802.11 WiFi; however, power management, critical latency and cost are key concerns in the 802.15.4 standard, which makes it a seemingly ideal fit for something like TTL flash radio communication.