
Body network spars with Bluetooth
Backers of the IEEE 802.15.6 effort say the standard could be completed this year and products based on it could ship in 2012. The specification promises a range of implementations roughly on par with Bluetooth bandwidth and range but at much lower power consumption and less interference.
GE aims to use the technology in a broad range of hospital patient monitors. Since 2008, it has lobbied the U.S. Federal Communications Commission to open up spectrum in the 2.4 GHz band for such devices, replacing today’s expensive and cumbersome wired links.
"Cables, cables, cables are what we see in the hospital today tethering patients to beds and machines and generating motion artifacts and false alarms," said David Davenport, an engineer in GE’s labs, speaking at an evening session at the International Solid State Circuits Conference here.
The FCC could rule on the spectrum use this year, opening the door to products in 2012. "The future looks very bright for smart bandages," said Davenport.
The 802.15.6 group is resolving about 100 technical comments on the second draft of its proposed standard. Companies including Broadcom, Texas Instruments and Toumaz Technology are interested in developing chips for the spec.
There’s no shortage of wireless options for health care systems. Wi-Fi and Zigbee proponents also have big initiatives in medical.
The Continua Health Alliance and the Wi-Fi Alliance announced Tuesday an agreement to work together to promote Wi-Fi in medical and fitness electronics and to conduct joint technical reviews to ensure interoperability. The Wi-Fi group is exploring whether it needs certification standards unique to medical and fitness products.
Continua, which sets standards for connected medical devices, has already adopted multiple wireless technologies including Bluetooth.
As for the 802.15.6 effort, Samsung’s mobile phone group has proposed one of three physical layers for the draft standard, targeting links between handsets. It uses an electric field similar to near-field communications to establish connections at 21 or 32 MHz that transmit from 164 Kbits/second to 1.3 Mbits/s of data up to three meters.
A separate narrowband PHY for 802.15.6 proposed by the MedWin Alliance–which includes GE, Philips, TI and Toumaz—targets mainly medical apps running anywhere from 100 Kbits/s to 1 Mbit/s. The PHY is geared for peak power consumption of less than three milliamps, said Anuj Batra, a senior member of TI’s technical staff, speaking at the ISSCC event..
The narrowband approach embraces slices of spectrum ranging from the 400 MHz MICS band to GE’s 2.4 GHz proposal. It supports as many as 64 BANs co-existing in a 36 square foot space, using constant symbol rates and differential PSK modulation to maximize data rates and simplify radio designs.
Japan’s National Institute of Information and Communications Technology sponsored work on a version of the 802.15.6 spec using ultrawideband technology. It will enable data rates of about 2 Mbits/s over three meters using 7.25 to 10 GHz UWB links, said Huan-Bang Li, a senior researcher in NICT’s medical group.
Once the standard is set, the MedWin Alliance is expected to work out a certification process. Despite its broad backing, the technology will be at least a year behind Bluetooth Low Energy which adopted its standard in July.
