SAN FRANCISCO, Calif. The cost of the latest Wi-Fi and Bluetooth links are headed south, and WiMax may come to a cellphone near you soon. Those were some of the conclusions from an afternoon session on wireless networks at the International Solid State Circuits Conference here Tuesday (Feb. 5).
Atheros Communications hit a twofer with integrated 802.11n and Bluetooth devices described at ISSCC. In other wireless developments, STMicroelectronics disclosed early work toward bringing Wi-Fi and WiMax into the cellphone.
"We are very proud of the die size of this chip," said Masoud Zagari, director of analog engineering at Atheros who delivered a paper on an integrated .11n chip.
Zagari claimed the paper was the first published report of a .11n chip with integrated radio and baseband, although other vendors are preparing similar parts, he said. The 130nm device measures just 32 mm-squared.
The chip, expected to ship soon, implements a 2x2 MIMO channel architecture and delivers throughput of about 205 Mbits/second. Eventually, vendors will be able to craft four-channel .11n parts that hit data rates up to 600 Mbits/second, he said.
More integration is also part of the road map for next-generation Wi-Fi chips, as low-noise amplifiers, power amplifiers and harmonic filters move on chip eventually.
Separately, Atheros also delivered a paper on an integrated Bluetooth 2.1 chip. Its die size is 9.2mm-squared, shaving a square millimeter off the smallest chips announced by Broadcom Corp. at last year's ISSCC.
"We picked analog architectures for the smallest die area," said Dave Weber, an analog design manager who presented the paper. "A few pennies are the difference that makes your profit margin in Bluetooth these days," he added.
For its part, STM described early research prototypes on the road to creating a single chip that will bring .11n and WiMax into a cellphone. In separate papers, STM described transmitter and receiver blocks that handle both networks in the 2.4 GHz band.
The company is just two weeks away from taping out a follow-on research prototype chip that puts the Wi-Fi/WiMax transceiver and synthesizer on a single die. All the parts are on a 65nm process, but commercial versions may be in a finer geometry.
The separate receiver, transmitter and synthesizer blocks now dissipate about 270 mW total. But that will fall as the blocks are brought on to a single die and go through a process shrink, said Andras Pozsgay, an RF R&D project leader at STM.
The chip delivers data rates up to a Mbit/s over a 10 MHz WiMax band. It could also be tailored to handle the LTE next-generation cellular standard since both LTE and WiMax use OFDM technology.
"There are a lot of cellular companies interested in WiMax these days including Motorola and Sprint," Pozsgay said.