The performance of directive aerials in complex u.h.f. fields

The paper describes an investigation, at frequencies of 580 and 904 Mc/s, of the apparent gains relative to a half-wavelength dipole of a number of directive aerials at a typical selection of receiving sites in urban and rural areas. It is shown that variations of the apparent gains occur, as a result of the complexity of the radio field patterns generally found at such sites, to an extent which may be significant in the estimation of the coverage of transmitters operating in the broadcasting bands IV and V.