A Review of Mapping Functions for the Radio Path Delay in the Neutral Atmosphere, GT-PR-NMA-2152

We present a review of developed mapping functions used to map the radio wave propagation delay, caused by the neutral atmosphere, from the zenith direction to a given elevation angle or vice versa. Mapping functions exist for the total delay, the hydrostatic (sometimes incorrectly referred to as dry), and the wet delay.

Depending on the required accuracy for the application and if information on the state of the atmosphere is available we recommend to use different types of mapping functions.