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To: straight life who wrote (23693)	3/3/1999 10:04:00 AM
From: Clarksterh	Read Replies (1) \| Respond to of 152472

Straight Life - 75% less RF power for CDMA That's a pretty good guess. It is almost certainly less than TDMA systems, but probably more than 1/2 the power needed for TDMA. As for whether the spreading helps reduce the damage, I don't really know but I doubt it. The reason is that the effect on a material (tissue in this case) of one frequency compared to a very close neighboring frequency is normally pretty similar. There are some frequency specific effects, but most are not that strong a function of frequency. In order to see much difference you normally need to change the frequency by an amount which a significant fraction of the starting frequency. CDMAOne spreads the signal by much less than 1%. Hope this helps. Clark

To: straight life who wrote (23693)	3/3/1999 10:15:00 AM
From: engineer	Read Replies (2) \| Respond to of 152472

the RF characteristics of TDMA is such that it is a fixed signal at 700 mW, constant carrier mode. The CDMa phone ranges from 200 mW max power to less than 1 micro Watt close to the cell. The actual stuff falls off at about r**4, which means it gets lower by the radius to the 4th power. Some practical numbers....if the cell radius were say 10 miles and the max power at the edge were 200 mW, then by the time you get to 7 miles, it would be less than 100mW, by the time you get to 5 miles it is less than 10mW, and by the time you get to 2 miles, it runs at about 10 micro watts. From there on in the power will reach 1 uW fast. So if you were always less than half the distance to the cell site, the ratio of the CDMA average and the TDMA would be like 700/7 or about 100 times lower power, thus the .75% may be close. At full range it is like 28%, at close in it is like .000143%. If you wanted real close numbers set this up in excel and calculate it and plot it at various distances.