Using the SPECTRAN as a Simple Pulsed Radar

#1 · 24/08/2021, 11:34

Quote from brto on 24/08/2021, 11:34
I have a SPECTRAN V6 - RSA 2000X which I have been using for ESM work. And I have been using the Tx channel and signal generator block in RTSA to generate simple Tx signals for Rx testing. All works great and very impressive.

Is it possible to use the SPECTRAN to build a simple pulsed radar system?

Load an arbitrary radar waveform from an IQ file (e.g. LFM / NLFM) and send through the Tx Channel.

Sync up the Tx and Rx channels to the start of the pulse.

Repeat this single waveform at a fixed PRF.

Ideally I would like to control the waveform and the pulse timing in real-time to allow for changes to the pulse frequency / bandwidth / pulse width / PRF etc. But just repeating a single pulse at a fixed PRF and getting Tx and Rx synced would be great.

The questions I have are:

Can I load in an arbitrary waveform from an IQ data file into the SPECTRAN?

I see there is a Raster Image option mentioned in the link below? Do you have any examples / guidance on how to use this?

Do you intend to add the ability to load an IQ file directly: rather than via a raster image? This would be a powerful and flexible addition.

Raster Image (Load a JPG, PNG, BMP or TIFF and convert it to I/Q)

IQ Signal Generator – Aaronia SPECTRAN V6 Support Forum

How do I sync the Tx and Rx timing?

Is this achieved via the hardware TRG port? I couldn't find any information on what this port is or how to use it.

What is a suitable TRG signal: is it just a square wave / rising edge? Is there a minimum pulse width / power level?

If the Tx and Rx were not synced then I guess I could the couple the Tx signal into Rx2 and use it as a timing reference: and then sync up Rx1 and Rx2 (and hence Tx) in post processing. Assuming Rx1 and Rx2 are time synced.

Just wondering if the capability exists in hardware / software for use as a low cost radar platform and if any of your customers has done something similar. I would be happy to discuss further on email.

Many thanks in advance,

Brian

I have a SPECTRAN V6 - RSA 2000X which I have been using for ESM work. And I have been using the Tx channel and signal generator block in RTSA to generate simple Tx signals for Rx testing. All works great and very impressive.

Is it possible to use the SPECTRAN to build a simple pulsed radar system?

Load an arbitrary radar waveform from an IQ file (e.g. LFM / NLFM) and send through the Tx Channel.
Sync up the Tx and Rx channels to the start of the pulse.
Repeat this single waveform at a fixed PRF.

Ideally I would like to control the waveform and the pulse timing in real-time to allow for changes to the pulse frequency / bandwidth / pulse width / PRF etc. But just repeating a single pulse at a fixed PRF and getting Tx and Rx synced would be great.

The questions I have are:

Can I load in an arbitrary waveform from an IQ data file into the SPECTRAN?
- I see there is a Raster Image option mentioned in the link below? Do you have any examples / guidance on how to use this?
- Do you intend to add the ability to load an IQ file directly: rather than via a raster image? This would be a powerful and flexible addition.
- Raster Image (Load a JPG, PNG, BMP or TIFF and convert it to I/Q)
- IQ Signal Generator – Aaronia SPECTRAN V6 Support Forum
How do I sync the Tx and Rx timing?
- Is this achieved via the hardware TRG port? I couldn't find any information on what this port is or how to use it.
- What is a suitable TRG signal: is it just a square wave / rising edge? Is there a minimum pulse width / power level?

If the Tx and Rx were not synced then I guess I could the couple the Tx signal into Rx2 and use it as a timing reference: and then sync up Rx1 and Rx2 (and hence Tx) in post processing. Assuming Rx1 and Rx2 are time synced.

Just wondering if the capability exists in hardware / software for use as a low cost radar platform and if any of your customers has done something similar. I would be happy to discuss further on email.

Many thanks in advance,

Brian

#2 · 25/08/2021, 09:15

First of all you can use the File Reader or the File Source block to load/stream any IQ data to the Tx

Concerning the "hot connection" between Rx and Tx you for sure are looking for the new Stream Portal block which should do exactly the job your are looking for.

#3 · 26/08/2021, 11:39

Quote from DevSF on 26/08/2021, 11:39
Hi, looks like a nice project and in general this should be possible to do. As I know until now nobody has implemented a radar with the Spectran V6. But it is not a new idea, internally we are talking about that, as always it is a matter of priority. Currently we are using multiple third-party radar devices in our geolocation systems.

Can I load in an arbitrary waveform from an IQ data file into the SPECTRAN?

I see there is a Raster Image option mentioned in the link below? Do you have any examples / guidance on how to use this?

Do you intend to add the ability to load an IQ file directly: rather than via a raster image? This would be a powerful and flexible addition.

Raster Image (Load a JPG, PNG, BMP or TIFF and convert it to I/Q)

IQ Signal Generator – Aaronia SPECTRAN V6 Support Forum

There are different ways to feed the Spectran V6 with the Tx Pattern:

For your first tests the Pulse generator in the IQ Signal Generator block should be a good starting point.

You can replay a waveform from file with the File Reader or the File Source block as already mentioned from AdminTC.

You should also be able to read/generate and manipulate an IQ Pattern with the Script block. Or you manipulate the IQ Signal Generator with the Script block. This is quite flexible but much more work.

For the Raster Image I added an example in the IQ Signal Generator topic.

https://v6-forum.aaronia.de/forum/topic/iq-signal-generator/

It is also possible to load an 8k IQ Sample into the Spectran V6, played as loop, but not as single shot.

I added it to our todo list, but with low priority: “Read an IQ Pattern from file into the IQ Signal Generator”

How do I sync the Tx and Rx timing?

Is this achieved via the hardware TRG port? I couldn't find any information on what this port is or how to use it.

What is a suitable TRG signal: is it just a square wave / rising edge? Is there a minimum pulse width / power level?

If you use one Spectran V6 for Tx and Rx1, Rx2 the streams should be already synchronized. If you use two V6 controlled by one computer they are also synchronized but only within a view microseconds.

Because of other priorities we have still no implementation for the REF, TRG and PPM IO. This will come in future with firmware updates. If you use two V6 and you need more accuracy, please give us some feedback.

For more clock accuracy depending on your test results you might need to have the OCXO option.

Hi, looks like a nice project and in general this should be possible to do. As I know until now nobody has implemented a radar with the Spectran V6. But it is not a new idea, internally we are talking about that, as always it is a matter of priority. Currently we are using multiple third-party radar devices in our geolocation systems.

Can I load in an arbitrary waveform from an IQ data file into the SPECTRAN?
I see there is a Raster Image option mentioned in the link below? Do you have any examples / guidance on how to use this?
Do you intend to add the ability to load an IQ file directly: rather than via a raster image? This would be a powerful and flexible addition.
Raster Image (Load a JPG, PNG, BMP or TIFF and convert it to I/Q)
IQ Signal Generator – Aaronia SPECTRAN V6 Support Forum

There are different ways to feed the Spectran V6 with the Tx Pattern:

For your first tests the Pulse generator in the IQ Signal Generator block should be a good starting point.
You can replay a waveform from file with the File Reader or the File Source block as already mentioned from AdminTC.
You should also be able to read/generate and manipulate an IQ Pattern with the Script block. Or you manipulate the IQ Signal Generator with the Script block. This is quite flexible but much more work.
For the Raster Image I added an example in the IQ Signal Generator topic.

https://v6-forum.aaronia.de/forum/topic/iq-signal-generator/

It is also possible to load an 8k IQ Sample into the Spectran V6, played as loop, but not as single shot.

I added it to our todo list, but with low priority: “Read an IQ Pattern from file into the IQ Signal Generator”

How do I sync the Tx and Rx timing?
- Is this achieved via the hardware TRG port? I couldn't find any information on what this port is or how to use it.
- What is a suitable TRG signal: is it just a square wave / rising edge? Is there a minimum pulse width / power level?

If you use one Spectran V6 for Tx and Rx1, Rx2 the streams should be already synchronized. If you use two V6 controlled by one computer they are also synchronized but only within a view microseconds.

Because of other priorities we have still no implementation for the REF, TRG and PPM IO. This will come in future with firmware updates. If you use two V6 and you need more accuracy, please give us some feedback.

For more clock accuracy depending on your test results you might need to have the OCXO option.

#4 · 01/09/2021, 15:55

Many thanks to both of you: AdminTC and DevSF.

You have given me some good directions to try out next. I will try to stream IQ from file into TX as a start.

I will keep you posted as to progress and findings.

Best regards,

Brian