I would like to develope a program to download the frequency response of a filter (passband: 890-915MHz and 935-960MHz) from a HP8753D/E network analyzer to a PC via GPIB, and then generate the time domain response in the PC using IFFT. I have the following question:
1. Can I get frequency spectrum data from the NA via GPIB? Is the data good enough that I can generate time domain response from it (given that I have set the NA properly)?
2. If the answer of the previous question is YES, how fast can the NA send data to the PC? Since I want the time domain waveform to be updated every 0.5 second at least, the data rate has to be fast enough. I will be using the NI GPIB-USB-HS USB GPIB controller, which is claimed to have transfer rate of >1.8MB/s (IEEE 488.1), >7.2MB/s (HS488). But I think the bottleneck should be at the NA side.
3. Which development tools is the best in my case? I think LabVIEW and MATLAB are good choices but I am not sure if I can do IFFT in LabVIEW, as well as how hard to develope an application in MATLAB.
Since I dont know much about GPIB and IFFT..etc, I would appreciate it if anyone who have tackled similiar problems could give me some advice.
Re: Question about Network Analyzer-PC Interfacing Using GPI
Fenrir said:
1. Can I get frequency spectrum data from the NA via GPIB? Is the data good enough that I can generate time domain response from it (given that I have set the NA properly)?
Yes they are! Data sent via GP-IB contains Frequency points and the complex measurement.
2. If the answer of the previous question is YES, how fast can the NA send data to the PC? Since I want the time domain waveform to be updated every 0.5 second at least, the data rate has to be fast enough. I will be using the NI GPIB-USB-HS USB GPIB controller, which is claimed to have transfer rate of >1.8MB/s (IEEE 488.1), >7.2MB/s (HS488). But I think the bottleneck should be at the NA side.
The necessary time is dependent on many factors, the 1st is number of points. Usually time needed to transer data is seconds rater than tents of second.
In any cases trasfert rate is dominated by instrument, not by the board on PC.
Even the "slow" IEEE488.1 is many time faster than the typical transert rate of any instruments (less than 9600 bps).
3. Which development tools is the best in my case? I think LabVIEW and MATLAB are good choices but I am not sure if I can do IFFT in LabVIEW, as well as how hard to develope an application in MATLAB.
In the past i've a wrong idea to add to my VNA an offline time domain capability... of course it didn't work . For my opinion, the maximum obtainable, but decisely incomplete solution is a commercial software called SPview.