Electronic device having isolated antenna structures

An electronic device, comprising:

• a housing having peripheral conductive structures and a planar conductive layer extending between first and second segments of the peripheral conductive structures;
• a first dielectric-filled gap in the peripheral conductive structures that separates the first segment from a third segment of the peripheral conductive structures;
• a second dielectric-filled gap in the peripheral conductive structures that separates the second segment from the third segment;
• a first antenna resonating element formed from at least the third segment of the peripheral conductive structures;
• an antenna ground formed from at least the planar conductive layer and the first and second segments of the peripheral conductive structures;
• an adjustable component coupled between the third segment of the peripheral conductive structures and the antenna ground;
• a dielectric substrate;
• and
• metal traces on the dielectric substrate that form a second antenna resonating element, wherein the second antenna resonating element includes a first portion that extends parallel to the first and second segments and that is coupled to a positive antenna feed terminal and a second portion that extends parallel to the first and second segments and that is interposed between the first dielectric-filled gap and the first portion.

An electronic device, comprising:

• a housing having peripheral conductive structures with first and second dielectric-filled gaps;
• a first antenna resonating element arm for a first antenna, wherein the first antenna resonating element arm has a first end at the first dielectric-filled gap and an opposing second end at the second dielectric-filled gap;
• a second antenna resonating element arm for a second antenna, wherein the second antenna resonating element arm has a first end coupled to a positive antenna feed terminal and a second end that opposes the first end, the second end of the second antenna resonating element arm being interposed between the first dielectric-filled gap and the first end of the second antenna resonating element arm;
• an antenna ground;
• a return path for the second antenna that is coupled between the second antenna resonating element arm and the antenna ground;
• and
• a capacitor interposed on the return path between the second antenna resonating element arm and the antenna ground.