So what is mobile WiMax?

It is broadband Internet access delivered wirelessly to you wherever you are.

For starters, mobile WiMax will probably come from a PC card or a chip in your laptop that allows you to get Internet access. It's similar to Wi-Fi, except that the coverage will be more extensive.

Down the road, new uses are envisioned: WiMax chips installed in cars to provide navigation or cameras that come with the chips.

Speeds: It's expected that the service can deliver up to 20 to 30 megabits per second, a lot faster than DSL or cable, which runs from 1 to 8 megabits.

However, those speeds are possible only if few people are using the service. It's more likely the speeds will be about 2 to 3 Mbps. As demand for faster speeds grows, it can be increased.

Mo Shakouri, vice president of marketing at the WiMAX Forum, said mobile WiMax can reach 30 megabit speeds for each 10 MHz of spectrum. For perspective, Sprint and Clearwire have about 100 MHz, so they are could provide up to 300 megabits.

Cost: Based on what service providers say, they are expecting to charge more than rates for DSL or cable today because their service, they say, is more valuable.

Radio cost: One of the biggest reasons cellular chipsets have not been integrated into consumer-electronic devices more readily is they cost a lot. WiMax chipsets are supposed to be cheaper. Because they aren't much bigger than Wi-Fi chipsets today, the silicon expense should not be much higher.