New metro WiFi product boasts greater coverage, bandwidth
- By William Jackson
- Jun 05, 2006
CHICAGO'With interest growing in municipal wireless networking, new schemes are being proposed to solve problems with range, bandwidth, scalability, mobility and complexity in current WiFi deployments.
Wavion Inc., an Israeli company with offices in San Jose, Calif., is touting what it calls the first metro-scale access points using multiple-input, multiple-output technology.
'We're not introducing a product at this time,' said marketing VP Alan Menezes. But the technology is being previewed this week at the Globalcomm telecom tradeshow.
Where traditional WiFi access points use two receiving antennas and a single antenna for transmitting, each Wavion access point will have six radios and antennas using complex signal processing to shape the transmission channels for maximum bandwidth and coverage.
'This is very intense computation,' said Wavion CTO Mati Wax. The computational overhead is handled by a proprietary chip set developed by Wavion.
WiFi technology covers the spectrum of the evolving 802.11 family of standards from the Institute of Electrical and Electronics Engineers. Client hardware equipped with WiFi chips can communicate wirelessly with access points wired into a LAN. For large-scale implementations such as municipal networks, the wireless network usually is extended through Mesh WiFi, in which access points act as routers and communicate with each other so each does not have to be wired directly into the LAN.
Although simple in concept, implementation is complicated by the limited range of each access point and the bandwidth consumed in multiple wireless hops back to the wired LAN. The holy grail of municipal networking is a solution that will solve these problems while leveraging the existing base of client-side WiFi equipment.
Cellular-type solutions with more powerful base stations have been proposed, and Motorola Inc. offers its Motomesh multiradio system. But each of the four radios in each Motomesh access point operates independently. Two of the radios use the company's proprietary Mesh Enabled Architecture rather than WiFi.
The six radios in each of Wavion's MIMO array access points will work together. The access point uses algorithms to shape the radio beam by weighting the signal of each antenna on a packet-by-packet basis. This should boost range and penetration, reducing the number of access points needed in most coverage areas. It boosts its scalability with a technology called space-division multiple access that creates virtual channels, sending up to four packets simultaneously to different clients over the same frequency.
As a result, Menezes says, 'we can provide 54 Mbps well beyond where conventional access points can even have a signal.'
At the same time, it could reduce the number of access points needed to cover a given area by up to two thirds. This could eliminate the need for meshing access points, thereby eliminating hops and reducing bandwidth consumption. Because each radio is WiFi, the system should work with existing 802.11a, b or g client equipment.
Menezes said Wavion hopes to release a commercial product this summer. The cost of each access point probably will be 20 to 40 percent more than conventional access points, but the company is betting that it can reduce the total number of access points needed and reduce the overall cost of a deployment.
William Jackson is a Maryland-based freelance writer.