BS ISO 16457:2022

What is ISO 16457 - IRI model and extensions to the plasmasphere about? 

ISO 16457 is a standard that covers IRI model and extensions to the plasmasphere, enabling precision and accuracy in navigational systems. 

ISO 16457 provides guidance to potential users for the specification of the global distribution of ionosphere densities and temperatures, as well as the total content of electrons in the height interval from 50 km to 1500 km. 

ISO 16457 includes and explains several options for a plasmaspheric extension of the model, embracing the geographical area between latitudes of 80°S and 80°N and longitudes of 0°E to 360°E, for any time of day, any day of year, and various solar and magnetic activity conditions. 

In ISO 16457, a brief introduction to ionospheric and plasmaspheric physics is given in Annex A. Annex B provides an overview of physical models, because they are important for understanding and modelling the physical processes that produce the ionospheric plasma. 

Who is ISO 16457 - IRI model and extensions to the plasmasphere for? 

ISO 16457 on IRI model and extensions to the plasmasphere applies to: 

• Space research companies 
• Space organizations 
• Aerospace industry 
• Research and development institutions
• Navigational satellite systems 
• Global positioning systems 
• Radio and television operators 
• Weather forecasters 

Why should you use ISO 16457 - IRI model and extensions to the plasmasphere? 

The ionosphere is the region of the Earth's atmosphere in the height interval from 50 km to 1500 km containing weakly ionized cold plasma. This model for the representation of the ionospheric and plasmaspheric plasma parameters is important to a wide spectrum of applications. Electromagnetic waves travelling through the ionized plasma in the Earth’s environment experience retardation and refraction effects. 

ISO 16457 provides users guidance on general considerations, applicability, model description, model content and inputs, and real-time IRI to mitigate losses of navigation signal phase and amplitude lock. 

ISO 16457 provides users guidance on plasmasphere extension of IRI model, including extrapolation of IRI profiles, GCPM, image/RPI plasmasphere model and IZMIRAN plasmasphere model to determine the monthly average behaviour of space plasma with improved accuracy. 

With obedience and compliance to ISO 16457, users can assess IRI models to reduce the precise positioning convergence time and mitigate problems with HF communications, HF direction finding, radar clutter and disruption in communication channels. 

What’s changed since the last update? 

BS ISO 16457:2022 supersedes BS ISO 16457:2014, which is now withdrawn. 

Changes in BS ISO 16457:2022 include: 

• Adding a description of the newly developed real-time IRI (Clause 9) 
• Replacing one of the plasmaspheric extension models (GPID) that is no longer available with the option to extrapolate the standard IRI to plasmaspheric altitudes 
• Providing more detail and newer references for the IMAGE/RPI and IZMIRAN plasmaspheric extensions of IRI