Let me expand a little more. Teh WLL system is nothing more than a FIXED MOBILE handset. But the user expectations are that it has a large keyboard and a large handset. The WLL phones were designed to take the incoming wireless signal and convert it to run your house, so if you plugged it into your house wiring, it can power the house just line any incoming line would. The extra circuitry to run the house or convert to standard analog phone interfaces for such things as FAX or modem (known as BORSCHT? functions) costs more than a regular handset and the battery costs more than a regular handset, but the size allows cheaper components and cheaper PC boards to be used, so they somewhat offset each other. Cost is about the same.
As far as the infrastructure is concerned, it does not know if your phone is a mobile or a WLL phone, EXCEPT in the system talbes where they assign resources for handoff. There your phone registers with it's ID and the BTS assumes that it is a fixed phone and therefore does not assign as much handoff resources to it as it would a mobile.
If you examine the capacity equations as presented by Dr. Viterbi in the 1995 era, you find that he had a term in there for the mobility. This took the capacity from 10x to 22x for WLL. Then if you add the 1xEV upgrade, then you get 40% on top of that.
So to reiterate, the BTS channel card where the CSM chip set is, is no differnt from teh regular one they would use for a entirely mobile system. The BTS controller and the system parameters however would have to be setup for WLL, or mobile, or a mixture of both. As far as teh CSM is concenred the signal strength, signal mod and demod would be exactly the same. The radio would be the same. Cost would be EXACTLY the same.As a matter of fact, if someone like Sprint were to go into WLL in a big way, all they would need is some software to upgrade their BTS controller and some software in teh switch. Not much else.
Hope this helps.
(Technically challenged this week from only having a 26k dialup line in Colorado..Where is my HDR link?) |
