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Simulators >> RF Simulators >> How to plot power in dBm using Calculator of Spectre
https://designers-guide.org/forum/YaBB.pl?num=1331020437

Message started by DoYouLinux on Mar 5^th, 2012, 11:53pm

Title: How to plot power in dBm using Calculator of Spectre
Post by DoYouLinux on Mar 5^th, 2012, 11:53pm

Hi all,

It seems easy, but I could not make it anyway.

As you might know already, in Cadence Spectre, we can plot the spectrum of a signal (say, output of an amplifier) using "dft" function of the Calculator. But, this gives the magnitude of the result in Volt. When I use "dBm" function, it gave me wrong calculation which did not correspond to the value of conversion from Volt to dBm. Also, I could not find the definition of the function "dBm" and also no specification for the reference resistance ...

Could anyone suggest me how to plot the spectrum in dBm on the Y axis please ??

Thanks a lot in advance :)

DYL

Title: Re: How to plot power in dBm using Calculator of Spectre
Post by weber8722 on Mar 6^th, 2012, 4:09am

I think dbm will take 50Ohms as reference. So if you want full control on Rref better use your own expression.