Interplanetary Scintillation of Radio Sources at Metre Wavelengths--II: Theory

Interplanetary scintillation is being used, in a survey of radio sources, to study angular structure in the range $$0^{\prime\prime}.1-1^{\prime\prime}$$ at a frequency of 81.5 MHz. The application of diffraction theory to scintillation at this frequency is discussed, and the diffracting parameters of the interplanetary medium are derived. The dependence of scintillation index on angular structure and receiver bandwidth is determined.