The competition between LTE and mobile WiMax is getting pretty intense, considering LTE doesn't exist and mobile WiMax is not yet delivered.

But that is precisely why the technologies are at each other's throats. LTE is the anointed successor of the mobile operators' 3G systems, but the upstart WiMax has a lot of backers. And the hype has to start now, because it takes a long while to build a mobile network, and a lot of decisions will be made now, in this pre-delivery phase.

There's a very serious and refined hype war going on. And if the WiMax pitch is right, everyone benefits, because operators can choose between two essentially similar networks, driving down the prices of both. And users can choose between data-centric and voice-centric networks - and maybe get the best of both worlds.

At least, that's the view of Paul Senior, chief technology officer of Airspan. We spoke to him because he inadvertently started a storm last week, with reported comments about an FDD version of WiMax, which could release WiMax from its current spectrum ghetto - comments which the WiMax Forum clarified, saying it had no immediate FDD plans.

FDD is vitally important to create a mobile WiMax that can compete effectively with LTE, said Senior. But first, we asked him, who is right? Is there an FDD version of mobile Wimax on the way, or is the Forum right when it says it hasn't decided yet?

FDD WiMax is real enough to plan for

"Both of us are right, but we are talking about different aspects of the same thing," explained Senior. "It's complicated."

To build a mobile WiMax system, there has to be a standard, further refined with "profiles" that make sure implementations will interoperate. The more mature fixed WiMax standard already has both FDD and TDD options, certified by the Forum.