Tunable antenna with slot-based parasitic element

摘要

Electronic devices may be provided that contain wireless communications circuitry. The wireless communications circuitry may include radio-frequency transceiver circuitry and antenna structures. The antenna structures may form a dual arm inverted-F antenna. The antenna may have a resonating element formed from portions of a peripheral conductive electronic device housing member and may have an antenna ground that is separated from the antenna resonating element by a gap. A short circuit path may bridge the gap. An antenna feed may be coupled across the gap in parallel with the short circuit path. Low band tuning may be provided using an adjustable inductor that bridges the gap. The antenna may have a slot-based parasitic antenna resonating element with a slot formed between portions of the peripheral conductive electronic device housing member and the antenna ground. An adjustable capacitor may bridge the slot to provide high band tuning.

主权项

1. An electronic device antenna, comprising:
an antenna ground; an inverted-F antenna resonating element that has a resonating element arm that is separated from the antenna ground by a gap, wherein the inverted-F antenna resonating element comprises a metal electronic device housing structure; a slot-based parasitic antenna resonating element that is near-field coupled to the inverted-F antenna resonating element and that comprises a slot having a first edge defined by the metal device housing structure and an opposing second edge defined by the antenna ground; and an antenna feed having a positive antenna feed terminal coupled to the inverted-F antenna resonating element and a ground antenna feed terminal coupled to the antenna ground, wherein the slot-based parasitic antenna resonating element is not directly fed by the antenna feed.