Patent ID: 9030371
Filing Date: 2015-05-12
Classification: H01F,H01P,H01Q

Abstract:
1. An antenna device comprising: an antenna element; and an impedance converting circuit connected to the antenna element; wherein the impedance converting circuit includes a first inductance element and a second inductance element; the first inductance element and the second inductance element are transformer-coupled with each other such that an equivalent negative inductance is generated and the equivalent negative inductance suppresses an effective inductance of the antenna element; the impedance converting circuit is connected to the antenna element such that the equivalent negative inductance generated by the transformer-coupled first inductance element and second inductance element is connected to the antenna element in series; the antenna element is a monopole antenna element; the antenna device is configured to transmit and receive signals in a UHF band; and the first inductance element and the second inductance element include conductor patterns that are disposed in a laminate in which a plurality of dielectric layers are laminated on each other, and the first inductance element and the second inductance element are coupled to each other inside the laminate.