Observations of Radio Refractivity Gradients in the Mekong Delta


  • C. A. Samson,

  • L. J. Maloney


Beyond-the-horizon 2-GHz radio paths in the Mekong Delta have shown large diurnal and seasonal propagation variations, which sometimes resulted in serious degradation of system performance. Measurements of refractivity gradients, in January and February 1970, using a high-resolution radiosonde technique showed a higher incidence of subrefraction than was indicated by the available climatological statistics. Low-based elevated layers with extreme superrefractive gradients were occasionally observed over wide areas.