Engineer, we have very big difficulties to understand each other.
>Perhaps you would take some time and understand what a near far
>problem is. there is NO signalling involved. It is a well known
>system limitation of CDMA. It is also present in wideband CDMA.
>the problem is that when you are moving, you must estimate the
>power contol from recived signal strength. Moving around and
>mutipath fading cause this estimate to be slightly innaccurate.
>If how ever you stay fixed, you estiamte is very good. So your
>power control is very good. If you have your power control
>estimate veyr good, then your power request to the basestation
>is exactly your theorectical limit and thus you use the minimum
>amount of power needed to complete your link. This power control >estimate is about 3dB, or a factor of two.
>
>GSM has no mechanism like this, as they must transmit full power all
>the time intot he chanel and when they use a time slot, they
>consume it fully.
What do you mean GSM has no mechanism like this, GSM has exactly this sort of function, where the strength of the signal is used to adjust the power on the handset and the base station. This power strength adjustment consumes very little capacity.
Secondly, there is a difference between a) transmission power, that you are talking about, and b) transmission capacity, that you should be talking about.
Thirdly, lets suppose, for argument's sake, that the power adjustment algorithm with CDMA1 is so heavy that it uses 50% of the capacity (that the WLL can utilize without that algorithm). Would it make WLL substantially cheaper? Nope.
- rajala
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