The effect of small amplitude wave irregularities on radio wave parameters

Wave irregularities in electron concentration are considered, noting that other irregularity structures can be thought of as a superposition of such irregularities. Under certain conditions, wave irregularities give rise to simple expressions for variations in the group and phase path, angle of arrival and Doppler shift of radio waves reflected from the ionosphere. The method developed is quite general, but multiplicative irregularities in particular are considered (at all heights the irregularity amplitude is a constant fraction of the background electron concentration). The irregularities have sufficiently small amplitude that only one ray is reflected close to normal incidence. The earth's magnetic field is neglected, which does not affect the general nature of the results.