The ICAO Standard for the State AIP (from Annex 15) includes:
ENR 1.6.1 Primary radar
Description of primary radar services and procedures, including:
1) supplementary services;
2) the application of radar control service;
3) radar and air-ground communication failure procedures;
4) voice and CPDLC position reporting requirements; and
5) graphic portrayal of area of radar coverage.
The following sections include a similar Standard for SSR and ADS-B.
The US, although not adhering to the ICAO AIP structure, includes a graphical portrayal of the location of radar head sites at AIM, Section 5, fig 4-5-5.