Two of the wave of newer metro-scale wireless equipment firms release news on deployments: Wavion, InspiAir, Go Networks, and Cohda Wireless are in the wave of startup vendors that came in being after BelAir, SkyPilot, Strix, and Tropos became established (but still startup) players. (Cisco and Motorola may have acquired and built metro-scale and mesh technology, but they're hardly startups.) These firms all employ techniques to allow greater range and greater spatial reuse of frequencies than the established players, typically via multiple antennas to allow beamforming and/or spatial multiplexing (unique data streams that follow disparate spatial paths using the same frequencies).
Wavion notes today that CONNX, a Maryland network operator, will deploy 120 of their APs. Their AllCoNet (Alleghany County Network)is one of the earliest municipal wireless networks, and the organization did rigorous testing of a host of mesh and metro-scale devices. The group claims that just 12 Wavion devices (with six transceivers and six antennas) cover a square mile. In most competing deployments, 25 to 50 APs are recommended, according to my many sources on this matter.
Wavion has said in the past that they plan to add SDMA, a method of beamforming a signal to specific clients in such a way that other clients on the same frequencies receive nearly zero energy, enabling simultaneous reuse of frequencies over space. That SDMA mode isn't yet out, and some engineers I've spoken to think that the current Wi-Fi MAC can't accommodate this mode. Wavion has acknowledged it's a challenge, but they believe it's got a solution.
Meanwhile, InspiAir, a company that boasts in its press release that it violates people's notions of the laws of physics, has formally unveiled a network covering Helsinki, Finland's central core. The network was biult with local firm Omni-Directional Communication Products (OCP). The firm says they've monkeyed with standard Wi-Fi to support dramatically higher areas of coverage with good throughput.
The press announcement says only 14 access points were required to cover the area in question, the size of which isn't defined, and thus that number provides no guidance in comparison to other systems. Update: Esme Vos has the details: It's a 4 sq. km (1.5 sq. mi) installation, but they told her only 2 APs are being used; their press release distinctly says 14. They also told her indoor coverage was hit or miss. If you're not attempting full indoor coverage, their competitors would also recommend a lower range of APs per square mile.
They note their APs use 60-degree sectorized antennas, offering 1.6 km reach in near-line-of-sight (nLOS) positioning. Their network operates at high 802.11b speeds--they suggest 6 Mbps--with fast 5 to 7 millisecond handoffs for mobile users. Service will run about €2 ($2.70) per day and €15 ($20) per month.