The Institute of Electrical and Electronics Engineers (IEEE) adopted a dual-use home networking standard positioned both as a high-speed Bluetooth competitor and as a more efficient, more reliable alternative to WiFi for distributing standard-definition (SD) and high-definition (HD) digital video around the house.
The new 2.4GHz standard, dubbed 802.15.3, is designed to coexist with 2.4GHz WiFi and Bluetooth devices, so the standard’s authors expect networked homes to use WiFi for data networking and 802.15.3 for a separate A/V network.
The standard features a top raw data rate of 55Mbps at 50 meters (165 feet) but offers 22Mbps speed at 100 meters (330 feet). It automatically changes channels if a channel is already in use by another wireless device. All told, it specifies raw data rates of 11Mbps, 22Mbps, 33Mbps, 44Mbps and 55Mbps and links up to 245 wireless consumer devices in a home.
By the end of 2004, adapters could be available to convert USB2 and 1394 connections into wireless 802.15.3 connections, said Robert Heile, chairman of the IEEE’s 802.15 working group.
Like Bluetooth, the standard is battery-friendly, so it can be built into PDAs and other portable devices, Heile said. Unlike Bluetooth with its 1Mbps data rate, the new standard will support quick transfers of large files, including multimedia files, and be able to replace wired 1394 connections on digital camcorders. To extend battery life, the standard’s power output steps down from a maximum 125mW at 100 meters as devices get closer.
As a WiFi alternative, the new standard’s bandwidth efficiency and inherent quality of service solution makes it possible to simultaneously stream seven broadcast-definition digital programs at 6Mbps each, Heile said. Alternately, the standard supports two simultaneous 19.2Mbps high-definition video streams or one HD stream combined with multiple video and uncompressed-audio streams, he said.
Heile said the standard’s data rate is comparable to that of 54Mbps WiFi products (based either on the 2.4GHz 802.11g standard or the 5GHz 802.11a standard). However, he called the new standard “very efficient,” allowing for net throughput exceeding 45 Mbps. The two WiFi standard’s throughput drops to 29Mbps because of “ethernet overhead,” he said.