2 port vector network analyzer

Hi all,

I want to test 2 parabolic dish (connected with feedhorn antenna) using 1 agilent vector network analyzer E5071B. I want to measure S11,S12,S21,S22. I have kept distance between the 2 dish about 1.5m. I am getting S11 and S22 about -12dB at the frequency between 2.3 to 2.4GHz. And S12 and S21 about -20dB.

I have a question.

1) Since I need to get the gain value in dBi, which value should I take? S11,S22,S12 or S21 to calculate.

2)How can I get an excel format graph from the S parameter images in the agilent vector network analyzer?


Plz reply me urgently.

Waiting for your reply. Very kind of you.



Thanx.

Regards,
Saran

You can not get dBi with network analyser.
You need to test the measurements in Antenna chamber.
Antenna is basically one port device and you can not apply as two port measurement with two antennas at some distance apart. radiation pattern determines the dBi not S-parameter.

Instead saving as picture you can save as csV format which can be opened by xls.

Hi All,

Since i'm using agilent vector network analyzer e5071b to test the antenna measurement, I need to test using parabolic dish(connected with feedhorn) using vna named above.

Can u tell me how to setup the dish antenna ? I think I can test s11 and s22 only.

Am I right? What I should I do if I want to test S12 and S21? How to setup the measurement?

Anyway, when i'm using Port 1 by connecting a dish antenna, I'm getting -10dB from S11 and I disconnect the cable and fixed to Port 2 to check S22 , I'm getting -10dB as well.



How to convert the S11 plot of the E5071B into excel format?


Plz reply urgently. Waiting for ur reply. Very kind of you.


Thank you.


Regards,
Saran

You read the manual for this NWA. I am sure that you will get answer

Hi Kspalla,

I got ur answer. Can u give me answer for other questions that i shoot to you.?

Very kind of you.


Waiting for your reply.


Regards,
Saran

I an not clear about the question/?
make simple sentences and pictures, or write a document on your test procedure and send me.

Hi kspalla,

Since i'm using agilent network analyzer e5071b to test the antenna measurement, I need to test using parabolic dish(connected with feedhorn) using network analyzer.

Can u tell me how to setup the dish antenna ? I think I can test s11 and s22 only.

Am I right? What should I do if I want to test S12 and S21?

Anyway, when i'm using Port 1 by connecting a dish antenna, I'm getting -10dB from S11 and I disconnect the cable and fixed to Port 2 to check S22 , I'm getting -10dB as well.



How to convert the S11 plot of the E5071B into excel format?


Plz reply urgently. Waiting for ur reply. Very kind of you.


Thank you.


Regards,
Saran

You can test S11 only there is no other test that you can do.
To the Q: How to convert the S11 plot of the E5071B into excel format?
Answer is present in second reply.

Hi kspalla,

Since i'm using agilent network analyzer e5071b to test the antenna measurement, I need to test using parabolic dish(connected with feedhorn) using network analyzer.

Can u tell me how to setup the dish antenna ? I think I can test s11 and s22 only.

Am I right? What should I do if I want to test S12 and S21?

Anyway, when i'm using Port 1 by connecting a dish antenna, I'm getting -10dB from S11 and I disconnect the cable and fixed to Port 2 to check S22 , I'm getting -10dB as well.



How to convert the S11 plot of the E5071B into excel format?


Plz reply urgently. Waiting for ur reply. Very kind of you.


Hi Kspalla,

Can I reconfirm with u again about the antenna measurement using agilent network analyzer? If I want to use 2 horn antenna to measure s parameters using agilent network analyzer since there are 2 port in the equipment. How to set-up it? Is there a way?

Or as u said, only S11 can be measured. U told me that can't set-up for S12,S21 using network analyzer. How else can I measure S12,S21? Give me some idea, plz.

Waiting for ur reply.

Thank you.


Regards,
Saran

Added after 30 minutes:

Hi kspalla,

Do u have skype id? Where r u from?


Waiting for your reply.


Thanx.

Regards,
Saran

I do not have skype ID, I am from Bangalore India

Added after 15 seconds:

you can PM me

I also want to know the answer about plootting VNA data in exel
I am using 8753D VNA and can save data (Data only/raw data/format data)and
can open in exel but how to interpret it
e.g. each row represents 2 values separated by comma
so what does represent 1 st row and what does 2nd row
I think frequency not included in that data so i can add that
but how to interpret for Y AXIS Data(Return loss in dB
reply me plz

A single-antenna method for traceable antenna gain measurement
Glimm, J.; Harms, R.; Munter, K.; Spitzer, M.; Pape, R.
Electromagnetic Compatibility, IEEE Transactions on
Volume 41, Issue 4, Nov 1999 Page(s):436 - 439
Digital Object Identifier 10.1109/15.809845
Summary:A simple method is introduced to measure the gain factor of a single preferably directional linearily polarized antenna in whatever distance. It requires only equipment for usual insertion loss measurement and the antenna itself in front of a totally reflecting surface simulating a second identical antenna as the image of the antenna to be calibrated. This speeds up such measurements considerably and, therefore, is very cost efficient. Its results can easily be made traceable to national standards

Added after 10 minutes:

Make certain the antennas are co-polarized, make certain you are in the far field for both antennas, you need to know how much power is at the antenna connector input, how much path loss between the two antennas. Subtract the path loss and power input from the S21, then divide the S21 in half. That should provide the antenna gain in dBi.

As for interpreting the S2P data, look at the entry for S2P data in wikipedia. The paragraph under "List format". Here is the link: http://en.wikipedia.org/wiki/Scattering_parameters
Good luck!