- 31st January 2009, 02:15 #1
## dbc dbm

How to convert dBc to dBm? Thanks.

- 31st January 2009, 02:15

- 31st January 2009, 04:13 #2

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## dbc to dbm

dBm and dBc are completely different so there is no 'conversion' between the two.

dBm - indicates the power measurement relative to 1 milliwatt. 0 dBm means no change from 1 mW, i.e. a power of exactly 1 mW. 3 dBm means 3 dB greater than 0 dBm. dBm is the relative difference to a fixed reference power of 1 mW.

dBc — indicates the power relative to the power of the main carrier frequency; typically used to describe spurs, noise, channel crosstalk, and intermodal signals which may interfere with the carrier. dBc is the relative difference to an arbitrary reference power level, the power level of the carrier frequency.

- 31st January 2009, 13:33 #3

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## dbm dbc

well, you could convert between them for a specific application. If you had a spur that was -50 dBc, and the carrier was at +10 dBm, then the spur would also be at -40 dBm.

- 31st January 2009, 23:47 #4

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## dbm to dbc

Both of RealAEL and biff44 are right.dBm is compared with 1mW(dBm=10log(Power/1mW),and dBc is compared with carrier power(carrier(dBm)-power(dBm)).

- 31st January 2009, 23:47

- 1st February 2009, 01:49 #5

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## dbm to dbc conversion

I think RealAEL is wrong and biff44 is right.

- 1st February 2009, 11:12 #6

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## convert dbm to dbc

everything RealAEL said is correct. I just gave a numerical example to further clarify his point.

- 1st February 2009, 20:14 #7

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## dbc to dbm conversion

Update: I think RealAEL is wrong and biff44 is wrong.

- 1st February 2009, 20:46 #8

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## convert dbc to dbm

Originally Posted by**yendori**

May we share your knowledge ?

- 1st February 2009, 23:52 #9

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## dbc power

If you know that both are wrong, then I conclude that you own the truth. Right ?

May we share your knowledge ?

- 21st July 2010, 04:09 #10

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## How to convert dBc to dBm? Thanks.

I think RealAEL is right