Any explanation would help

Collect the S-parameter data for the ZFL-500LN into a spreadsheet, and use that data to address the following questions.

1. Normalize the plot of adjusted |S21|² (GF) vs frequency with respect to the maximum and display it in a linear-linear plot.

2. At what frequency is the normalized GF = 0.5 (i.e., 50% down from 1.0 ?; no need to

interpolatejust find the frequency point that yields the closest to 50% down). Since the ZFL-500 it is a broadband LNA, this becomes the estimate of the bandwidth, Df, which you should state.

In many ways, amplifiers behave as filters with gain. The high-end rolloff of GF with frequency in broadband amplifiers can often be modeled as a low-pass filter. A very common low-pass filter characteristic is the Butterworth function: B(f) = [1 + (f/fC)²ⁿ ], where n is an integer and called the order of the filter.¹ For many broadband amplifiers, a good first guess is a second-order Butterworth response, n = 2.

3. Independent of n, what is fC ?

4. Calculate the 2^nd-order (n = 2) Butterworth function and add it to your normalized GF linear- linear plot. Comment on where in frequency the Butterworth response best fits the ZFL-500 data (i.e., low-, middle-, or high-frequency portions of the 10-2000 MHz frequency range).

5. A measure of the goodness of fit between the normalized GF curve and the Butterworth curve is given the expression:

=0

E(N) = (1/N) |_, | /

where | | denotes absolute value, GF,i and Bi are the forward normalized gain and Butterworth values at frequency i, and N is the number of frequency points. Calculate E(N) from i = 10.1 MHz to 1.0 GHz (N = 100), i = 10.1 MHz to 1.50 GHz (N = 150), and i = 10.1 MHz to 2.0 GHz (N = 200).

Which of the three E(N)s is the smallest, and by visual inspection of the curve in (d), provide a qualitative explanation why ?