Mobile telephone aerial formed on glass surface - consists of square element and adjacent rectangular strip of conductive material placed in or on car window

摘要

Aerial (19) has a conductive flat element (24), pref. approximately square, deposited on a surface (20) of the glass pane (15) and a ground strip (25), sepd. and insulated from the first element and pref. long and approximately rectangular, deposited adjacent. The first element (24) has a connection (28) and the ground strip connection (30) to a coaxial cable (26,27,29) attached to the telephone. The dimensions of the 2 elements (24,25) are selected to match the frequency range of the telephone n the band 800-960 MHz. The square element (24) pref. has an edge length (b) of about 1/4th of the wavelength of the centre of the band multiplied by a reduction factor, resulting in a size of 5.9 cm for the band 825-890 MHz. The groundstrip is pref. 3b wide its height less than b pref. about 1/4th, i.e. 17.5 cm wide and 1.4 cm high and the distance between the elements is pref. 0.5 cm for the above band. The connection point (28) is pref. placed in a corner close to the groundstrip and to the other connection (30). USE/ADVANTAGE - The aerial is less subject to damage than currently used whip or rod aerials. It creates no wind resistance and no wind noise during driving. Its transmission characteristics are very similar to those of conventional aerials, esp. for high energy transmissions. The aerial is omni directional and highly tolerant for non vertical transmission directions. The aerial does not decrease the visibility significantly due to its small size. It is inexpensive to mfr.