RoamAD's so-far unique implementation of zone coverage with standard Wi-Fi used by Reach Wireless to offer service in Auckland's central business district: RoamAD uses 802.11b/g for their service and 802.11a for backhaul between points. They blanket an area by using as many as all of the legal, overlapping 802.11b/g channels with one card devoted to each channel in a chassis.
The VP of business development, Martin Levy, told me at 802.11 Planet last year that for their goals, of achieving a minimum of mid-300 Kbps throughout their zone, the interference across overlapping channels was unimportant compared to the additional, inexpensive coverage that their approach allowed.
The partner, Reach Wireless, will roll out RoamAD technology in all of the major markets in New Zealand. RoamAD hopes to sell its technology to cell carriers looking for major metropolitan coverage that can be offered at higher speeds but a fractional cost (with no licensing fees) as cellular broadband.