ML: Now you really have me confused.
First you wrote:
As a result, both from common sense and technical point of view, the BTS wanna serve the user as the fastest as possible so that it can go on serve for the next user. To slow things down can only have your throughput and capacity suffering and that doesn't make any sense.
Now when it comes to the fixed network you say:
There's no need to support the peak rate, because that is not sustainable anyway. </I>
So it appears you want the Base Station to serve the subscriber unit as fast as possible, but are not concerned that the fixed network will lack the capability to serve the Base Station at the fastest possible rate???
As a matter of fact from Q's presentation it stated that about 1.2Mbps per sector. Then one T1 line will be able to handle it.
OK! That's 3 T1's per BTS per EV-DO carrier (3 sector cell)! $1800 per month per BSC in backhaul fees.
So let's say we run these in a dynamic network, and it's 6PM. People arrive home from work, and turn on the computer. Additional users are being added to the system, in addition to the after school crowd. So throughput to the user is being reduced (user notices the slow down in performance). At the same time, the network has cleared a FDD carrier from voice activity and will deploy an additional EV-DO carrier to add capacity and increase available bandwidth to existing data users and new users.
A second carrier becomes active! Now you need 6 T1's per 3 secton base station. Monthly lease is now $3600 per Base Station.
In a network of 2,200 Base Stations. The yearly cost associated with 3 additional T1's per Base Station is about 47 million.
It is far better and cheaper to moderate the user experience to 70-80kbs via the subscriber unit at all times, than provide them 500kbs when the system is empty, and only 70kbs when the system is full. No matter how many times you tell them. "Well, you are only paying for 70kbs!" They won't care. These customers are not technology geeks. All they know is that it used to be fast, and now it's slow and they will want "the problem" fixed! It's only human nature!
As a matter of fact, in initial deployment stage! You may only need to add one additional T1 per BSC with a 60-80kbs moderated service, and increase your backhaul commitments as usage grows on a subscriber basis.
In the above scenario, you could provide full time moderated 60-70kbs to allot more users, cheaper, with allot less complaints. Than providing them with higher data rates when the system is empty, and slowing the experience (to advertised levels) when the systems become full!
PCSTEL |
