Map a US latitude/longitude to its FCC spectrum-licensing geographies — Cellular Market Area (CMA), Basic Trading Area (BTA), Major Trading Area (MTA), Partial Economic Area (PEA), and the BEA/EAG/MEA/REAG economic areas — plus the 2020 Census block FIPS, county, and block population. Keyless, public-domain (FCC). These market areas define spectrum-license boundaries (which CMA/BTA/PEA a point falls in) — distinct from ordinary geocoding, and not derivable by an LLM.