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To: waitwatchwander who wrote (15042)	9/16/1998 1:50:00 AM
From: Clarksterh	Read Replies (1) \| Respond to of 152472

Increasing power to stay connected: Within IS-95 this is not, in general, allowed. The whole purpose of the much talked about power control is to prevent this very scenario. No user is allowed to be transmitting such that the receiver is getting more power from them than from the other users. Having said that, excess power transmission capability could be useful under some of the conditions given by Maurice. For instance, if there is only one cell and a fixed amount of background noise then the users who could transmit more power would be able to stay in contact further out than the lesser powered users. And in the area of speculation - real knowledge requires models which I do not have access to - it is possible that it makes a difference if there is a failure mode for a CDMAOne cell system where the cells shrink away from one another due to too many users in neighboring cells causing noise (just as the conversations that you are not listening to at a party are noise), then the overpowered phones will be able to communicate further into the dead zones between cells. In the process they (these overpowered phones in aggragate)further increase the noise floor for users in other cells and enlarge the dead zones. But this cannot happen unless the system is first overloaded to such a degree that the cells develop dead zones - i.e. disparity in power transmission cannot cause a capacity problem but it may aggravate one. Clark PS Putting bigger batteries (e.g. D instead of AAA) in a phone will extend it's battery life, but not it's power output. First, all the batteries you mentioned have the same voltage (like water pressure). For this you should be grateful since a battery with a significantly higher voltage would just fry your phone. Second, in any case it is the electronics that determine the maximum power output. A good analogy is a car engine. Putting in significantly more energetic fuel will not make you car more powerful - in all likelihood your engine will self-destruct or just not function. To get more power you need to redesign the engine.

To: waitwatchwander who wrote (15042)	9/16/1998 3:12:00 AM
From: Ramus	Read Replies (3) \| Respond to of 152472

I think the question here is "how does turning up the RF output power increase the bandwidth?" When the output RF amplifier is operated linearly, that is, the output waveform is a replica(although greater amplitude) of the input waveform, then amplification without distortion is taking place. If you drive an amplifier too hard, so that the output waveform is distorted, this can produce distortion products. These are generally referred to as intermodulation distortion products. In digital systems these distortion products are usually measured as adjacent channel power, since if the channels are close together these products may fall within an adjacent channel and interfere with it. A measure of how well an amplifier linearly amplifies a digital modulation signal might be its Adjacent Channel Power Rejection or ACPR. So, if you overdrive a given amplifier it might produce more adjacent channel power...yes, turning up the power too much can further spread an already spread signal(CDMA)....and interfere with adjacent channels. It's true that increasing the power from a single mobile increases the overall noise floor for other users and decreases the capacity of the cell. But, it could also have the effect of increasing the noise floor in adjacent channels. W.

To: waitwatchwander who wrote (15042)	9/16/1998 9:50:00 AM
From: engineer	Respond to of 152472

I don't think the power is more, but the noise is more. The way CDMA works, the better you control closed loop power control and the better you approach true gaussian white noise, the better the CDMA signal works. If you don't do so good on making the IS-95 waverform, then you produce alot of in band spurious noise and this looks just like another CDMA phone which is SUPPOSED to look like GWN in the bandwidth. Suppose that your phone produced 25% extra noise, then each 4 phones like this would reduce the available calls on the system by one user! If your sector coverage was 30 users, then if they all used this type of phone, then you would get 25% less usage in the system (or 7-8 users less). Makes your air time minutes pricing plan go all out of control. Note that I simplified this alot, since hte noise does not add in a linear fashion, but compounds alot very fast. More like a 1% noise problem and a 1% error in power control can cause as much as a 10% loss in capacity. also if your filters are not good enough (i.e sharp enough to cut off the frequency range), then you spill over into the next band (Each CDMA signal frequency band is actually 1.25 MHz wide, holding 20-50 calls) and cause noise in the next band. The true CDMA waverform is a real test of perfection. You must do it right to get it to work. I have not seen a Korean phone spec in many months, so this is speculation as to what they really do.