for passive sniffing, it looks like you can run the cheaper module at only $2k, which is approachable for researchers.. actually fully loaded price tag is $11k or $4k as you need GPSDO also.. but $4k is almost approachable I guess..
Amazingly, you can probably get a reasonable GPSDO from eBay for a couple hundred dollars. I was running an Ettus B210 off of an eBay GPSDO and had about a 1Hz frequency offset relative to an LTE tower at 1800MHz. Pretty cool!
Sadly not yet. I’m very intrigued though! At one point I was going to try setting up a similar project using a… BladeRF? I forget which open LTE project it was.
[edit to add] https://www.ettus.com/all-products/ub210-kit/