Cascaded Noise Figure Calculator

Calculate system noise figure for up to 6 cascaded stages using the Friis formula.

Cascaded Noise Figure (Friis Formula)

Enter the gain and noise figure for each stage. Leave unused stages blank. For passive loss stages (filters, cables), enter negative gain and NF equal to the loss.

Stage	Gain (dB)	NF (dB)
1 (LNA)
2
3
4
5
6

Friis Formula:
F_total = F1 + (F2-1)/G1 + (F3-1)/(G1*G2) + …
T_e = 290 * (F – 1) K