Study of spatial characteristics of artificial field aligned scattering

Artificial field-aligned irregularities (AFAI) induced by ionospheric heating has the property of artificial field-aligned scattering (AFAS) to incident wave, which can be used in long distance VHF transmissions. According to the physical model of AFAS, a calculation model has been deduced for the available area supporting AFAS transmission for a given heating station. Simulation results show that the available area increase with decreasing inclination, what means a great advantage for mid- and low-latitude in AFAS transmissions. The results also show that, with the increasing height, the available area increase, decrease and have a maximum value while the inclination less than 66°, large than 71°, and between 66° and 71° respectively. These results can be used in selection of the heating location, terminals and parameters in AFAS transmission applications.