guys, what the hell does this question mean?(Bellamy, Digital telephony class)

[digme]

what is the effective S to I(signal to Interference ratio) of a single CDMA uplink channel operating at a distance that is twice as far from the base as 62 other channels?


Ok, i know it's english problem(forgive me, english is not my mothre tongue ) does the above question mean, there's 63 channels, and one of them(the person who is talking on this specific channel) is twice the distance away from the other 62 people that are communicating to the same tower? or something else? thanx

 

[LordMagnusKain]

it means that thedistance to 62 people from base is X while the distance to the 63 is X*2.

 

[Kostya17]

Kinda difficult to understand the question (especially since I went thru similar class ages ago )

I guess this problem tests your knowledge of "signal strenth" vs. "distance". The rule of thumb for this case is power=1/distance^2. #63 is twice as far as others, therefore the signal power will be 25% of what others get. Assuming the same noise level, the S/I will be 4 times worse.

I'm too lazy to convert that to db--you can do it yourself