While researching for parts, I also found this one: https://www.amazon.com/dp/B07RR86PFC/
It goes up to 10GHz, and it operates on 5V. Would that also be an option, and possibly allow to get rid of the boost converter too?
Thanks OP. The detector itself has a Pulse response time of 6 ns/10 ns (fall/rise) but of course the whole system will always be slower. 1 s is a lot though, got probably nothing to do with the sampling done by the esp.
https://www.amazon.com/dp/B07FHZXTCZ?ref=ppx_yo2ov_dt_b_fed_...
Specifications: Working frequency: 1M--10000MHz Measurement power: -55dBm to -0dbm Output voltage: 0.33- -1.65V Detection slope: -22mv/dBm (typical value) Input impedance: 50Ω Supply voltage: 7-15V Size: as the picture Weight:7g