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Thanh
05-11-2003, 12:48 PM
Hello :)

Does anyone know how high is the output power of a CDMA phone..?

Like GSM, the 900 MHz is 2 watts max, 1800 MHz is 1 watt max.... how is CDMA 2000 1x??? (800 MHz)

Any information (in watts, not db, please) is highly appreciated!

Kind regards....
Thanh

Ericdog
09-01-2004, 02:32 PM
OK, I have a little info.

Firstly, dBm isnt so hard to work with, so I'll give you a quick run-down.

dBm is referenced to 1 milliwatt of power, so 0dBm=1 milliwatt (mW).

Every 10dB in the dBm scale is a factor of 10, so:

10dBm = 10 Milliwatts
20dBm = 100 Milliwatts
30dBm = 1 Watt

Also, every 3dB is a factor of 2, so:

13dBm = 20 Milliwatts.

Negative dBm are less than 1 Milliwatt, so:

-10dBm = 0.1 Milliwatts, or 100 uW (micro watts)..

Hope this helps with understanding dBm...

Now for the output power... I have field test turned on in my Nokia CDMA, I have seen the TX power up to about 28dBm, which would be just above 500 Milliwatts. The phone only went up this high when I was in a bad coverage area. In normal coverage, it was down to -20dBm (10uW) and below. It seems that at most times, the output power of the CDMA phone is very low. I will test the maximum output power if you want me to and advise you of the results.

Cheers,

TLD

Thanh
10-01-2004, 09:44 AM
Hello :)

Thank you very very much for explaining that to me :) Now i know why those flashing antennas won't work with CDMA phones..... and i have been told that mine current phone goes with 0.2 - 0.3 watts normally (it's a Sanyo). But still, someone else told me that it is just like GSM, 2 Watts :)

Well, seing the total talktime of mine phone before the battery goes flat, and how hot that battery gets when talking, i would assume it's somewhere near a gigawatt or so :)

Thanks a lot for the info! You don't need to test that explicit, i just wanted to know in general :)

Kind regards.....
your Thanh

Ericdog
10-01-2004, 10:10 AM
My pleasure.


Hello :)

Thank you very very much for explaining that to me :) Now i know why those flashing antennas won't work with CDMA phones..... and i have been told that mine current phone goes with 0.2 - 0.3 watts normally (it's a Sanyo). But still, someone else told me that it is just like GSM, 2 Watts :)

Well, seing the total talktime of mine phone before the battery goes flat, and how hot that battery gets when talking, i would assume it's somewhere near a gigawatt or so :)

Thanks a lot for the info! You don't need to test that explicit, i just wanted to know in general :)

Kind regards.....
your Thanh

superman
07-02-2004, 10:43 PM
u qute gsm with 2 watt 900mhz and 1 watt 1800 mhz
what I read somewhere is that 900 has 1 watt output and 1800/1900 uses 0.5 watt output pwr at the cell phone, so correct me if i am wrong, these specs can also be found in user manuals of dual band phones in the back under specs.