or 3 cascaded amplifier stages, each with a noise figures of 3 dB andpower gain of 10dB, determine the total noise figure

To determine the total noise figure for 3 cascaded amplifier stages, each with a noise figure of 3 dB and power gain of 10 dB, we can use the Friis formula.

The Friis formula states that the total noise figure (F_total) is equal to the sum of the individual noise figures (F_i) divided by the power gain (G_i) of each stage minus 1, all multiplied by the power gain of the entire system (G_total).

In this case, we have 3 cascaded stages, so we can calculate the total noise figure as follows:

F_total = (F_1 + F_2 + F_3) / (G_1 * G_2 * G_3) - 1

Given that each stage has a noise figure of 3 dB and power gain of 10 dB, we can convert these values to linear scale:

F_i = 10^(F_dB/10) = 10^(3/10) = 1.995

G_i = 10^(G_dB/10) = 10^(10/10) = 10

Substituting these values into the formula, we get:

F_total = (1.995 + 1.995 + 1.995) / (10 * 10 * 10) - 1 = 5.985 / 1000 - 1 = 0.005985 - 1 = -0.994015

Therefore, the total noise figure for the 3 cascaded amplifier stages is approximately -0.994015 dB.