Why is the Noise Factor that I've counted inconsistent with the result of Pnoise?

Hi everyone,

I've simulated the noise factor of Mixer ne600p in rfExamples library with PSS+Pnoise. With the Noise Summary printed, I calculated the Noise Factor, which is (total noise at output - load noise at output)/(source noise at output), then Noise Figure can be abtained with 10*lg(Noise Factor). However, my result is very different from the Noise Figure of Pnoise.

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Noise Summary:

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Device    Param             Noise Contribution    % Of Total

/rif           rn                5.70677e-19           23.13     IF_OUTPUT_Port
/q57        rb                2.86098e-19           11.60    
/rf            rn                2.74587e-19           11.13     RF_INPUT_Port
/q56        rb                2.71557e-19           11.01    
/r45         rn                1.60586e-19           6.51     
/q57        ic                1.54208e-19           6.25     
/q56        ic                1.1156e-19            4.52     
/rl1         rn                1.03425e-19           4.19     
/r44        rn                8.357e-20             3.39     
/r46        rn                7.25826e-20           2.94     
/q56        ib                5.65173e-20           2.29     
/q58b     rb                5.51435e-20           2.23     
/q58a     rb                5.51435e-20           2.23     
/lo          rn                4.66997e-20           1.89     
/q58a     ic                4.14535e-20           1.68     
/q58b     ic                4.14535e-20           1.68     
/q58b     ib                1.98622e-20           0.81     
/q58a     ib                1.98622e-20           0.81     
/q56      re                1.28295e-20           0.52     
/q57      re                1.27064e-20           0.51     
/q57      ib                7.93188e-21           0.32     
/q58b     re                3.43834e-21           0.14     
/q58a     re                3.43834e-21           0.14     
/q58a     rc                9.14375e-22           0.04     
/q58b     rc                9.14375e-22           0.04     
/q57      rc                9.88927e-23           0.00     
/q56      fn                4.43245e-23           0.00     
/q56      rc                1.67595e-23           0.00     
/q58b     fn                3.9707e-24            0.00     
/q58a     fn                3.9707e-24            0.00     
/q57      fn                1.26023e-24           0.00     
/rl1      fn                0                     0.00     
/rif      ext_file_noise    0                     0.00     
/rf       ext_file_noise    0                     0.00     
/r46      fn                0                     0.00     
/r45      fn                0                     0.00     
/r44      fn                0                     0.00     
/lo       ext_file_noise    0                     0.00     
/lm       fn                0                     0.00     
/lm       rn                0                     0.00     
/ldc      fn                0                     0.00     
/ldc      rn                0                     0.00     
/L1       fn                0                     0.00     
/L1       rn                0                     0.00     
/L0       fn                0                     0.00     
/L0       rn                0                     0.00     

Spot Noise Summary (in V^2/Hz) at 80M Hz Sorted By Noise Contributors
Total Summarized Noise = 2.46733e-18
Total Input Referred Noise = 8.63267e-18
The above noise summary info is for pnoise data

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Total Noise at Output: No^2 = 2.46733e-18 V^2/Hz

Load Noise at Output: Nl^2 = 5.70677e-19 V^2/Hz

Source Noise at Output: Ns^2 =  2.74587e-19 V^2/Hz

Noise Factor: N = (No^2 - Nl^2)/(Ns^2) = 6.90729 

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However, according to the Noise Factor curve of Pnoise, noise factor @

80MHz is 43.11, which is very larger than 6.90729.

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There must be something wrong. Anyone can help me?

Thanks in advance!