by Robert J. Wagman
Wireless is the next frontier, and its settlers are fighting with one another for space in their rush to stake a claim. For almost a decade the Federal Communications Commission (FCC) has tried to reserve a portion of the frequency spectrum to allow for the anticipated rapid expansion of wireless services. Now the agency finds itself caught in the middle of squabbles between proponents of different wireless technologies over who should get bandwidth priority.
The big winners were the makers of devices that use a technology known as HomeRF, or Home Radio Frequency, which enables the short-range transmission of digital voice and data between mobile devices and desktop devices. The FCC ruled that HomeRF could use up to 5MHz of the 2.4GHz radio band, up from the previously permissible 1MHz. This will allow for a significant increase in transmission speeds, from 2Mbps to 10Mbps, for the wireless transmission of data within 150 feet of RF-equipped devices such as laptops and PDAs. HomeRF uses a transmission method called “frequency hopping,” which means it continuously changes frequencies, making it difficult for unwanted guests to listen in.
But manufacturers of competing technology say that HomeRF will trample on their turf. “HomeRF is going to be hopping around in a broader spectrum, and that is going to cause interference all around the spectrum,” says Phil Bellanger, who heads the Wireless Ethernet Compatibility Alliance, composed of companies supporting a rival standard known as 802.11b. This technology, which uses direct sequence transmission and does not “hop,” allows for wireless connection speeds of up to 11Mbps.
The problem is that HomeRF, 802.11b, and other technologies like Bluetooth all share the same small area of the radio spectrum. As various devices using different technologies proliferate, some may interfere with one another, with the result that none will work correctly.
Prior to this decision by the FCC, there was a general movement within the industry to adopt 802.11b as the main wireless standard. It was believed that 802.11b advances would soon allow transmission speeds in excess of 20 Mbps. But HomeRF also supports voice, which 802.11b does not yet, and this was a major factor in the FCC decision.
In the past, the FCC has attempted to keep the area free for wireless users, but not regulate too closely. An FCC spokesman noted that proponents of 802.11b “are asking us to regulate a portion of the spectrum we have not in the past.” But if the FCC makes a decision that boosts one standard’s prospects over the other, businesses may never get the opportunity to choose the standard they prefer.