Exponential model of radio refractive index over india

Based on the afternoon radio sonde data of twelve stations in India during the years 1956¿1960, exponential model of radio refractive index has been derived and its limitations are discussed. It is found that the exponential model holds good satisfactorily over inland stations of north and central India and mainly during winter over Assam and coastal regions of West Bengal and Gujarat. The agreement is rather poor over the coastal stations of the peninsular India.