Loop antenna for mobile handset and other applications

Abstract

There is disclosed a loop antenna for mobile handsets and other devices. The antenna comprises a dielectric substrate () having first and second opposed surfaces and a conductive track () formed on the substrate (). A feed point () and a grounding point () are provided adjacent to each other on the first surface of the substrate (), with the conductive track () extending in generally opposite directions from the feed point () and grounding point () respectively and winding around the substrate () to the second surface and passing along a path generally opposite to the path taken on the first surface of the dielectric substrate (). The conductive tracks () then connect to respective sides of a conductive arrangement () that extends into a central part of a loop formed by the conductive track () on the second surface of the dielectric substrate (). The conductive arrangement () comprises both inductive and capacitive elements. The antenna can be multi-moded and operate in several frequency bands. Alternatively, the loop antenna is fed parasitically by a monopole or a feeding loop. The parasitic loop antenna my alternatively comprise a conductive loading plate instead of the conductive arrangement.