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Products => Test Equipment => Topic started by: freebil on September 18, 2016, 01:45:49 AM

Title: Vector network analyzer from rigol ds1054z
Post by: freebil on September 18, 2016, 01:45:49 AM
Hello. Is it possible to have the functionality of a network vector analyzer using a rigol ds1054z connecting to a pc writing code in matlab? So, is it possible to see vna functionality from matlab?
Title: Re: Vector network analyzer from rigol ds1054z
Post by: balu on September 18, 2016, 03:53:49 AM
Do you think about a configuration like this - see picture?
Title: Re: Vector network analyzer from rigol ds1054z
Post by: cncjerry on September 18, 2016, 04:03:24 AM
You can get scalar results that way but no phase, or at least, no accurate phase.

You can do this more simply by using the scope's FFT functionality with a broadband noise source.  You then put the scope in peak hold mode and use the noise source as the sweep generator.

Also, a directional coupler would be replaced with a reflection bridge which will give you SWR, definitely showing the tuning.  The coupler will also show the tuning but I never thought about the math required to get actual SWR using one.
Title: Re: Vector network analyzer from rigol ds1054z
Post by: hendorog on September 18, 2016, 08:14:01 AM
You can get scalar results that way but no phase, or at least, no accurate phase.

Also, a directional coupler would be replaced with a reflection bridge which will give you SWR, definitely showing the tuning.  The coupler will also show the tuning but I never thought about the math required to get actual SWR using one.

I think balu's design would work fine for both magnitude and phase - within the limitations of the device of course. Just need to zero out any offsets from the reference channel, and then any change in phase or magnitude has to be caused by the DUT.
Since the data will be in matlab then other more powerful calibrations can be done as well.

AFAIK there would be no difference between a coupler and a bridge, the maths is the same.

Title: Re: Vector network analyzer from rigol ds1054z
Post by: cncjerry on September 18, 2016, 11:06:30 AM
I was looking at Balu's method more closely and yes, I see now he is splitting the signal into two channels and you could see the phase delta between them.  I'll have to try that and compare it to a vna.
Title: Re: Vector network analyzer from rigol ds1054z
Post by: pascal_sweden on September 18, 2016, 08:32:57 PM
Is there software available for the setup described by Balu?

Does it support Siglent SDG1050 or SDG2040X as signal generator and DS1054Z as scope? :)