| Main | 
| Number 
 | Title | Status | Questions | 
| P.531-16 (09/2025) 
 | Ionospheric propagation data and prediction methods required for the design of satellite networks and systems | In force (Main) 
 | N/A | 
| 
 | 
| Previous versions | 
| Number 
 | Title | Status | Questions | 
| P.531-12 (09/2013) 
 | Ionospheric propagation data and prediction methods required for the design of satellite services and systems Licence Agreement for NeQuick2 Software: Please read the copyright document carefully before downloading, copying or using the licenced software
 | Superseded 
 | N/A | 
| P.531-4 (05/97) 
 | Ionospheric propagation data and prediction methods required for the design of satellite services and systems | Superseded 
 | N/A | 
| P.531-14 (08/2019) 
 | Ionospheric propagation data and prediction methods required for the design of satellite networks and systems | Superseded 
 | 218/3 | 
| P.531-15 (08/2023) 
 | Ionospheric propagation data and prediction methods required for the design of satellite networks and systems | Superseded 
 | 218/3 | 
| P.531-11 (02/2012) 
 | Ionospheric propagation data and prediction methods required for the design of satellite services and systems | Superseded 
 | 218/3 | 
| P.531-13 (09/2016) 
 | Ionospheric propagation data and prediction methods required for the design of satellite services and systems Licence Agreement for NeQuick2 Software: Please read the copyright document carefully before downloading, copying or using the licenced software.
 | Superseded 
 | N/A | 
| P.531-10 (10/09) 
 | Ionospheric propagation data and prediction methods required for the design of satellite services and systems | Superseded 
 | 218/3 | 
| P.531-9 (02/07) 
 | Ionospheric propagation data and prediction methods required for the design of satellite services and systems | Superseded 
 | 218/3 | 
| P.531-7 (04/03) 
 | Ionospheric propagation data and prediction methods required for the design of satellite services and systems | Superseded 
 | N/A | 
| P.531-6 (02/01) 
 | Ionospheric propagation data and prediction methods required for the design for the design of satellite services and systems | Superseded 
 | 218/3 | 
| P.531-8 (03/05) 
 | Ionospheric propagation data and prediction methods required for the design of satellite services and systems | Superseded 
 | 218/3 | 
| P.531-5 (07/99) 
 | Ionospheric propagation data and prediction methods required for the design of satellite services and systems | Superseded 
 | N/A | 
| P.531-3 (08/94) 
 | Ionospheric effects influencing radio systems involving spacecraft | Superseded 
 | N/A |