A study of ionospheric irregularities using a CW oblique incidence transmission

An account is given of measurements made of the phase path and the direction of arrival of a stable continuous-wave obliquely propagated signal, performed so as to study ionospheric irregularities. Use is made of the relationship, derived by Whitehead and Malek (1963), between group path and rate of change of phase with frequency. The carrier frequency was 3.399 MHz and the delta f determining the two sidebands was 2 kHz. The phase path variation was measured at the carrier frequency as was the amplitude and direction of arrival. The direction of arrival was measured using an Adcock type direction finder and the amplitude using the A3 method. The propagation path was approximately north-south and had a ground length of 102 km.