Does anyone know whether I can use a GPSDO with an SDR to have very accurate timestamps of each I/Q sample? I don't just want the sampling to run at the correct phase, and without drift, I want a timestamp. Could be any SDR, but I'd prefer something reasonably priced (under $1000). Most SDRs will happily take the 10MHz reference clock, but are not be able to ingest or output time.
(I always thought RS422 for the PPS signal is a bit fishy, not sure how jitter-y those transceivers are. That said the hardware I've seen uses >25Mbaud high-speed transceivers [ISL3180, THVD1452], maybe those are fine in that regard.)
A modern 5G base station kinda does what you describe. All SDR these days anyway :)
On the other hand, BladeRF has an FPGA on board, perhaps it can ingest PPS. It will still be quite a bit if work to write for the FPGA, but at least I'll not have to design PCBs, which is way above my skill level.
If you have a device that can record multiple bands simultaneously, and preserve timing between them, then you may be able to record both your target band and the GPS band and then use software later to reconstruct the time out of the GPS recording.
See: https://www.rtl-sdr.com/rtl-sdr-tutorial-gps-decoding-plotti...