Patch antenna

Wherein the patch antenna is an antenna version which is particularly suitable for integration on printed circuit boards. The patch antenna is often made of a rectangular metal surface, the longitudinal side corresponds to a length of λ / 2. So that the metal surface acts as a resonator similarly to the dipole antennas.

The patch antenna may have a directional effect, in particular when it is combined with an underlying, serving as a metal reflector surface. A single element can then achieve a gain of approximately 10 dBi.

The wide bandwidth of a patch antenna is strongly dependent on the ratio of substrate thickness and wavelength, as well as of the effective dielectric constant of the system. The width of the patch affects the bandwidth also.

Other refinements, such as the use of the parasitic patches in a variety of substrate materials, the broadband and the directivity of the antenna can be improved.

If several patches arranged in an array in front of a metal surface, increase gain and directivity effect on ( Panel Antenna ).

A patch antenna can be fed in various ways, for example, by means of a microstrip line or slot coupling. The type of feeding influences the broadband and the feedpoint impedance of the antenna.

For very high frequency bands, a patch antenna is often applied as a layer structure on a ceramic carrier. Ceramic is a very good insulator and impervious to moisture. It also has a low dielectric loss angle.

The antenna type is used among other things in mobile phones, Wi-Fi and DECT cordless phones. A variant of the patch antenna, the PIF antenna.