directivity

Noun

directivity (countable and uncountable, plural directivities)

1. A measure of the performance of an antenna compared to an isotropic antenna; the ratio of the maximum value of radiation intensity to the average radiation intensity.
2. Anisotropy in the propagation of earthquake waves in the direction of rupture.
3. (rare) Directionality
   • For higher degrees, the spatial integration tends to produce a cancellation and a rapid loss of visibility, although less rapidly for velocity measurement than for luminosity measurement, on account of the directivity of the velocity vector.1991, COSPAR. Plenary Meeting, Jean-Louis Fellous, COSPAR., Global change and relevant space observations: proceedings of Symposium 1 of the COSPAR twenty-eighth Plenary Meeting held in The Hague...
   • First we renounced the directivity of the velocity measurement by using a hot point whose size is of order of the wire diameter [4]. Numerical simulations have shown that the probe then measures the velocity modulus [5].2012, Russell J. Donnelly, Katepalli R. Streenivasan, Flow at Ultra-High Reynolds and Rayleigh Numbers: A Status Report, Springer Science & Business Media, →ISBN, page 337