Dear all,

I am measuring S21 response using Agilent VNA E5062A of a wireless channel by setting the sweep time to minimum to achieve a static channel. Does any one know the mathematical expression for the minimum sweep time? i understand it depends on no. of points , bandwidht as well as the IF filter setting, but i am not sure how do these factors relating to the minimum sweep time.

Thank you very much

I am measuring S21 response using Agilent VNA E5062A of a wireless channel by setting the sweep time to minimum to achieve a static channel. Does any one know the mathematical expression for the minimum sweep time? i understand it depends on no. of points , bandwidht as well as the IF filter setting, but i am not sure how do these factors relating to the minimum sweep time.

Thank you very much

But how does this no. of points and IF BW affect or relate to the minimum sweep time? is there any mathmatical expression?

I would recommend putting a quick program together that runs multiple sweeps with your setting and then dividing the overall time by the number of sweeps.

but this is the situaion:

for 1601pts, IFBW auto set to 3Khz (max for this VNA), min sweep time: 111.56ms, which is much less than the expression

(1/IFBW * NO. of pts)= 1/3000*1601 = 533.67 ms

for 801pts, min sweep time: 55.81ms, which is half of the 111.56ms, so it is believed that the min sweep time is inversely proportional to the NO. of pts, but still not sure how it relates to the IFBW and the exact mathmatical expression. I have sent email to the technique support in Singapore, they said they were not sure about this part as well.

:o Could anyone help me out? Thanks a million

The maximum IFBW of the E5062A is 30 kHz, not 3 kHz.

Then

a) 111.56ms / 1,601 pts = 69.7 microseconds / point

b) 1/IFBW = 1/30,000 = 33.3 microseconds / point

The difference between a) and b) is approx. 37 microseconds / point and it is an internal setup/meas overhead between a point and the next point for frequency change and so on. Generally, this overhead depends on actual measurement setting such as frequency interval, power setting, etc. So it's not written in a single formula. Also, the sweep time of the E5062A does not include display time, which is done independently.

I hope it helps to clarify your question.