Unstrung's Dan Jones notes that, with this week's announcement by Stella Doradus of a solid state remote electrical tilt WiMax antenna, vendors and operators are anticipating interference issues before WiMax networks have even been deployed.

As a next step, Jones says, Stella Doradus plans to automate the process of beam-forming. "Already familiar to vendors in the wireless LAN market, beam-forming is used by vendors like Xirrus Inc. and the now-defunct Vivato, an early pioneer of Wi-Fi switching, with varying degrees of success," he writes.

Still, Yankee Group analyst Phil Marshall says beam-forming won't solve all of WiMax's interference concerns. "It's part of the answer, particularly if you're using your beam for coverage, but if you're using it for capacity -- with lots of sites working together -- it gets pretty hard to steer the beam around," he says.