The structure of high-frequency ionospheric scatter signals

The paper reports measurements of amplitude distribution, lateral correlation, diversity effects and error rates of ionospheric scatter signals at a frequency near 70Mc/s. The results are discussed and it is concluded that a markedly non-Gaussian signal occurs at some times. The effects of signal structure are examined, and it is shown that the only effect is that some loss of diversity action would need to be included when deducing the performance of a link from the median signal and noise levels The signal/noise ratio required for various error rates in a non-diversity system is derived, together with information of use in estimating the feasibility of h.f. communication links. Some information on the diurnal variation of cosmic-noise intensity is given.