Poor signal on some SM's - What is the actual effect?

Hi,

We are having some discussions about this. The general assumption is that bad signal SM's will affect the overall sector capacity/quality. 

I'm not buying it directly. TDD is time divided, meaning that each SM gets a predefined "time to speak", which means that if he has poor signal, he will not have the time to transmit/receive all the data he may want. He will experience lower troughput, and the sector will carry on just fine.

Am i wrong?

Enable proportional scheduling on the AP and then go to stats on proportional schedular and you can see the airtime effects of a lower modualtion on airtime.  You will see that one bad client is in fact eating up quite a bit of airtime as the radio tries to maintain their downlink speed.  Enabling proportional schedular on the SU will then lower their guaranteed speed to attempt to match the airtime to all customers.  I think in TDD it does prevent a single time slot from being eaten up from a bad connection but overall AP airtime gets eaten up with lower modulations.  We just enabled proportioanl scheduling on all clients in the last week or two and see it helping with overall AP performance when clients signals cause lower modulations.  You may not sdee issues on AP that have a low subscriber count but it becomes a significant impact when you have a large number of clients connected.  I wish epmp had a similar feature.