Hi Jeffro,
Spike can save I/Q recordings in Zero span for 60 seconds. It saves the I/Q data in a basic 16-bit complex short binary format with descriptor file.
If you want to re-transmit a waveform, then you will need another piece of equipment. In the test equipment industry, this would be a vector signal generator. We make one that goes up to 2.5GHz but can only playback patterns that are 2048 I/Q samples long (very short). Something like an SDR would be capable of transmitting a waveform, although you would likely need to do some minor programming to set this up. We are working on a 6GHz VSG which would have the playback capability you are looking for, but won’t be released until later this year.
60 seconds worth of waveform at 20MHz BW is a lot of data and for instruments that have a fixed sized pattern memory buffer, you may struggle to find one for cheap with this amount of memory. 60 seconds at 20MS/s I/Q is 4.8GB stored as 16-bit complex values.
Regards,
Andrew