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justdream
2009-03-08, 11:58 PM
Guys, why signal strength is represented by negative powers? like: -77 dBm

mbo
2009-03-09, 12:11 AM
the response in the doc
BR:)

proy1_10
2009-03-09, 12:26 AM
Usually engineers are more interested to know how much is a magnitude more greater than other and become the dB who compares a magnitude respect the other one. If the magnitude measured is lower than the reference used the result is negative. I.e. if you compare 1uW vs. 1 mW result is -30 dB, and 30 dBmW are 1 dBW

Stantheman
2009-03-09, 05:38 AM
some Wiki info on the subject

http://en.wikipedia.org/wiki/Decibel

http://wapedia.mobi/en/dBm