Automobile antenna - providing circular horizontal radiation diagram and using half wavelength slits in T or L configuration

摘要

The antenna is formed by 2 slits (11,12) within an electrically conductive horizontal body panel. e.g. the automobile roof. The slits (11,12) are arranged in a T or L configuration, with a given spacing between them, the supply points (15,16) of both slits (11,12) coupled is a coaxial cable section (14), to which a coaxial antenna cable (19) is coupled. Pref. each slit (11,12) has a length of half a wavelength, each slit (11,12) provided on the underside with a conductive housing having a greater length and a width equal to a quarter wavelength. ADVANTAGE - Improved circularly of horizontal radiation diagram.