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Reg. Transmit & Receive power - RF Cafe Forums

Because of the high maintenance needed to monitor and filter spammers from the RF Cafe Forums, I decided that it would be best to just archive the pages to make all the good information posted in the past available for review. It is unfortunate that the scumbags of the world ruin an otherwise useful venue for people wanting to exchanged useful ideas and views. It seems that the more formal social media like Facebook pretty much dominate this kind of venue anymore anyway, so if you would like to post something on RF Cafe's Facebook page, please do.

Below are all of the forum threads, including all the responses to the original posts.

 Post subject: Reg. Transmit & Receive power
Posted: Fri Dec 22, 2006 7:27 am 

Joined: Fri Dec 22, 2006 6:44 am
Posts: 1
Location: INDIA
Can any one tell me the reson for changing the BTS transmit power in +ve value( dBm or Wtts) while the Mobile receiving power is -ve value.

look forward for your reply

 Post subject:
Posted: Thu Jan 11, 2007 1:19 pm 
User avatar

Joined: Thu Jan 11, 2007 12:59 pm
Posts: 16
Not sure if I understand you right, but I assume that you mean that output power is mentioned for an example as +20dBm, ie 100mW. A reciever will only recieve a fraction of this and according to the logarithmics it'll be for an example -60dBm, ie one millionth of a mW.

Some more information at www.producon.com/sm7ovk/dbformula.html


 Post subject:
Posted: Fri Jan 12, 2007 4:35 am 
User avatar

Joined: Fri Feb 17, 2006 12:07 pm
Posts: 268
Location: London UK
If the power at the input to a Black Box 2 port device is +N dBm and the attenuation through the Black Box is greater than N dB, then the output expressed as dBm will be a negative value, because you have used up all the +N decibels and the "Bank Account" goes into negative territory.

Your question, as Jens implies, was rather cryptic. Some more details would help us explain better.

Posted  11/12/2012
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