You can always make impedance measurements with a slotted line, 6-port reflectometer, or vector voltmeter if you don't have access to a VNA. My undergrad microwave professor had us learn on the slotted line before letting us touch the VNA.
I've got some steady-state 60GHz stuff I'd love to try (non-radar), but the equipment is prohibitively expensive.
Being able to analyze things with much less expensive, even if more labor intensive, tech would be welcome.