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Simulators >> RF Simulators >> Temperature setting for noise simulation using sp
https://designers-guide.org/forum/YaBB.pl?num=1190112138

Message started by humble_student on Sep 18^th, 2007, 3:42am

Title: Temperature setting for noise simulation using sp
Post by humble_student on Sep 18^th, 2007, 3:42am

Hi,

I have some questions regarding the noise simulation when doiong the sp analysis.
Qn1 : When i am simulating for the noise parameters (NFmin, Rn...) using the sp analysis, the temperature setting for the analysis should be at 290K or 300K?
Qn2 : The noise temperature setting for the port should be set at what value (0, 290 or 300 Kelvin) ?

best regds,
humble_student

Title: Re: Temperature setting for noise simulation using
Post by pancho_hideboo on Sep 19^th, 2007, 4:20am

Hi.

First NF dependency on temperature is different in ADS and Cadence Spectre.

In sp analysis of ADS, temperature of port is 290K which can't be changed by user.
While in Spectre, user can set any tempereture value in port but it's default value is 290K.

For both ADS and Spectre, user can set any value as analysis temperature.

Assume NF simulation of pi-type resistor attenuator(17dB) with port tempereture is 100K and analysis temperature is 100K,
Spectre gives you 17dB as NF but ADS gives you completely different NF value.

You might think the temperature dependency of NF is reasonable in Spectre than in ADS.
But From NF definition, NF is defined as NF=1+Teff/T0, where T0 is reference temperature(=port temperature)
and Teff is equivalent noise temperature of DUT(=analysis temperature).
Standard T0 is 290K. So NF of ADS is matched to standard definition of NF.

My recommendations are following

Port temperature should be 290K or blank.
About analysis temeperature, there is only trivial difference between 290K and 300K.
You don't need to care about choosing 290K or 300K.

But if you compare NF results strictly between ADS and Spectre, you have to set 290K for both port and analysis temeperature.

Title: Re: Temperature setting for noise simulation using
Post by humble_student on Sep 19^th, 2007, 7:02pm

Dear pancho_hideboo,

Thanks for the detail informations.

regds,
humble_student

Title: Re: Temperature setting for noise simulation using
Post by pancho_hideboo on Sep 20^th, 2007, 8:27am

The following is wrong.
But From NF definition, NF is defined as NF=1+Teff/T0, where T0 is reference temperature
(=port temperature)
and Teff is equivalent noise temperature of DUT(=analysis temperature).

I correct this like following.
But From NF definition, NF is defined as NF=1+Te/T0, where T0 is reference temperature
(=port temperature)
and Te is equivalent noise temperature of DUT(Te is dependent on analysis temperature).