https://www.bellnw.com/manufacturer/Narda/NBM-550.htm?gclid=EAIaIQobChMInJG1h8H86AIVB9bACh3FuA_nEAsYASABEgJPM_D_BwE
Pretty expensive.. not very informed on this subject ...but believe will go up to 50ghz
hope this helps
Customer support service by UserEcho
https://www.bellnw.com/manufacturer/Narda/NBM-550.htm?gclid=EAIaIQobChMInJG1h8H86AIVB9bACh3FuA_nEAsYASABEgJPM_D_BwE
Pretty expensive.. not very informed on this subject ...but believe will go up to 50ghz
hope this helps