Re: ADS Harmonic Balance Noise calculation

Hello,

I actually simulate with the Harmonic Balance Solver from Agilent ADS.

I specified ONE MIXER with Noise Figure = 7.
All other devices in the circuit are specified as NO NOISE or NOISE OFF.

Anyway, it calculates different Noise Figures if there are Resistors included, although these resistors are not noisy.

Does somebody know what's wrong ?

Thanks. elektr0

Added after 1 hours 5 minutes:

Ok, sorry.

Problem solved, the resistors were noisy too.

Anyway, there is still some mystic stuff around the noise simulation.

If I use V_Noise Sources to achieve a specified noise floor at the input, I can also do Noise Analysis over a defined bandwith and get the noise floor at other nodes in the circuit.

When calculating NOISE FIGURE, the V_Noise sources seem to be misunderstood.
E.g. V_Noise=-60dBm/sqrt(Hz) leads to -63 dBm Noise Floor at the mixer output, if the mixer has Noise Figure=3.
Isnt it the wrong direction. It should be -57 dBm...?