WLAN for voice.

Does anyone ever research the possibility of using WLAN for voice and high rate data service? From the specs, if we have enough base coverage, we can achieve the same service as 3G or even better, but with much low cost. The 802.11a support higher data rate than any current 3G specs, the cost of internet connection is much low than the switching network, no licience fee for the frequency band. What is the reason that none of phone is developed with WLAN?

Next phone generations will use it, check for example this link,

http://www.wlan-forum.com/article.php?sid=89

I guess will be interesting for what you are asking about :).

What you propose has already been done on an experimental basis. Voice over IP has been applied to 802.11 systems and there are several commercial systems that use 802.11 for city wide systems. They have nodes around town that connect to the wired internet.

The overall problem is economic and limited frequency. In silicon valley there was a system in the 918 MHz band that used frequency hopping. They had nodes all over the area. They finally went bankrupt because the number of users did not generate enough funds to pay for the system operation.

The 802.11 sustems have much higher capacity and therefore can handle more users. They stand a chance of being economic. They also have their nodes connected by DSL to the internet at each node.