Wireless Ethernet could become a standard feature of smart phones in the next two years if Bluetooth specialist CSR PLC gets its way. The company has packed a triple-mode a/b/g Wi-Fi adapter into a single ultra-small chip, complete with multiple antennae ready for 802.11n MIMO.
"Bluetooth will stay around for audio and for when you're on the road," said James Collier, CSR's chief technical officer and co-founder. "But we feel Wi-Fi will emerge too, for example to work with commercial access points." He added that emerging smart phone applications such as video streaming, uploading high-resolution camera-phone images, voice-over-IP and rich email could all require the extra speed of Wi-Fi.
CSR's CEO John Hodgson expects the percentage of phones with Wi-Fi to reach the low teens by mid 2006. "That's still 100m phones a year," he pointed out.
Called UniFi, the CSR chip is 6mm square and contains all the logic needed for Wi-Fi, including a hardware MAC with its own TCP/IP stack. Collier says one of his customers, ALPS, will use UniFi to build a complete double-sided Wi-Fi module just 8mm square – several times smaller than the modules used in PDAs today, for example.
CSR has chosen not to integrate Wi-Fi and Bluetooth onto the same chip. Although having the two share a single radio might look attractive, they will generally occupy different channels and switching from one to the other would disrupt a Bluetooth voice connection, Collier said.
The downside of Wi-Fi is its power consumption, with UniFi needing 300mW to stream data at 54Mbps (megabits per second). "Bluetooth is ubiquitous and has broader appeal than Wi-Fi, it's also a third of the cost and has much lower power consumption," Collier said, noting also that UniFi will cost around two- or three-times as much as Bluetooth.
He warns that there is a challenge though, and it's that Wi-Fi needs to become easier to use, with standard interfaces replacing device-specific drivers. "Wi-Fi is not seamless yet, and that's got to be sorted out before it will take off on phones. The best thing Bluetooth has done is come up with service profiles and we intend to continue that with Wi-Fi, so you won't need drivers anymore."