Retrieval of the horizontal and vertical refractivity fields using GPS

An investigation has been conducted into resolving the refractivity fields in the troposphere using tomographic techniques. Slant delays have been obtained using a network of ground based GPS receivers and then input into the tomography software. Results are presented that verify the accuracy of the GPS zenith delay measurement for two sites in the UK. Further results show a preliminary two-dimensional vertical slice of the troposphere, which compares favourably with a corresponding radiosonde profile