Hybrid antenna system for wearable devices
An antenna system includes a loop conductor and non-loop conductor configured to provide respective loop and dipole antenna functionality. A signal feed mechanism connects to both conductors at a signal feed point for simultaneous signal transceiving. The non-loop conductor comprises two elongate arms with an offset feed point creating shorter and longer arms, where the longer arm has increased width via a loop-shaped portion. When incorporated in eyewear devices, the loop-shaped portion extends circumferentially along a lens holder to retain lenses. The conductors may be configured through a diplexer for different frequency domains, with the non-loop conductor serving as a GPS antenna and the loop conductor as a data communication antenna. The radiation patterns of the conductors may be substantially orthogonal when driven by the signal feed mechanism. The system provides integrated antenna and mechanical functionality in wearable devices.
1 . An antenna system comprising:
a loop conductor configured to provide loop antenna functionality;
a non-loop conductor configured to provide dipole antenna functionality; and
a signal feed mechanism connected in common to the loop conductor and the non-loop conductor at a signal feed point to transceive electrical signals simultaneously through both the loop conductor and the non-loop conductor,
wherein the non-loop conductor is provided by a dipole conductor that comprises two elongate arms connected at adjacent ends thereof to the signal feed point, the feed point being offset from a lengthwise center of the dipole conductor, such that the dipole conductor is offset-fed and comprises a shorter arm and a longer arm; and
wherein the longer arm of the dipole conductor has, for at least part of its length, an increased width relative to the shorter arm of the dipole conductor, the increased width of the longer arm being provided by a loop-shaped portion of the dipole conductor.
2 . The antenna system of claim 1 , in which the loop conductor and the non-loop conductor are shaped and positioned such that a radiation pattern of the loop conductor is substantially orthogonal to a radiation pattern of the non-loop conductor, when both the loop conductor and the non-loop conductor are driven by the signal feed mechanism.
3 . The antenna system of claim 2 , in which the shape and spatial arrangement of the loop conductor and the non-loop conductor are such that the loop conductor and the non-loop conductor radiate with different respective polarizations, when driven by the signal feed mechanism.
4 . The antenna system of claim 1 , wherein the antenna system is incorporated in an electronics-enabled eyewear device, the loop-shaped portion of the dipole conductor comprising a lens retainer extending circumferentially along a lens holder defined by a frame of the eyewear device, the lens retainer being disposable between a locked condition in which it retains a lens in the lens holder, and a released condition in which it permits removal and replacement of the lens.
5 . The antenna system of claim 1 , in which the dipole conductor comprises:
a main portion that lies substantially within a plane defined by the loop conductor, the feed point being located in the main portion; and
for at least one of the ends of the dipole conductor, an angled end portion that extends transversely relative to the plane of the loop conductor.
6 . The antenna system of claim 1 , further comprising a diplexer connected to the non-loop conductor and to the loop conductor to provide frequency-domain multiplexing based on respective frequency domains of the loop conductor and the non-loop conductor.
7 . The antenna system of claim 6 , wherein the respective conductors and the diplexer are configured such that the non-loop conductor serves as a GPS antenna, and the loop conductor serves as a data communication antenna, the frequency domain of the loop conductor being higher than the frequency domain of the non-loop conductor.
8 . A wearable device comprising:
a body;
onboard electronics carried by the body; and
an antenna system connected to the onboard electronics and housed by the body to provide wireless connectivity to the onboard electronics, the antenna system comprising:
a loop conductor configured to provide loop antenna functionality;
a non-loop conductor configured to provide dipole antenna functionality; and
a signal feed mechanism connected in common to the loop conductor and the non-loop conductor at a signal feed point to transceive electrical signals simultaneously through both the loop conductor and the non-loop conductor,
wherein the non-loop conductor is provided by a dipole conductor that comprises two elongate arms connected at adjacent ends thereof to the signal feed point, the feed point being offset from a lengthwise center of the dipole conductor, such that the dipole conductor is offset-fed and comprises a shorter arm and a longer arm; and
wherein the longer arm of the dipole conductor has, for at least part of its length, an increased width relative to the shorter arm of the dipole conductor, the increased width of the longer arm being provided by a loop-shaped portion of the dipole conductor.
9 . An eyewear device comprising:
an eyewear body configured for supporting one or more lenses within view of a user;
onboard electronics incorporated in the eyewear body; and
an antenna system housed in the eyewear body and connected to the onboard electronics to provide wireless connectivity to the onboard electronics, the antenna system comprising:
a loop conductor configured to provide loop antenna functionality;
a non-loop conductor configured to provide dipole antenna functionality; and
a signal feed mechanism connected in common to the loop conductor and the non-loop conductor at a signal feed point to transceive electrical signals simultaneously through both the loop conductor and the non-loop conductor,
wherein the non-loop conductor is provided by a dipole conductor that comprises two elongate arms connected at adjacent ends thereof to the signal feed point, the feed point being offset from a lengthwise center of the dipole conductor, such that the dipole conductor is offset-fed and comprises a shorter arm and a longer arm; and
wherein the longer arm of the dipole conductor has, for at least part of its length, an increased width relative to the shorter arm of the dipole conductor, the increased width of the longer arm being provided by a loop-shaped portion of the dipole conductor.
10 . The eyewear device of claim 9 , wherein the loop conductor extends in a loop circumferentially around one of the lenses held by the eyewear body.
11 . The eyewear device of claim 10 , wherein the loop conductor is provided by a lens retainer element configured for engagement with a radially outer periphery of a lens held by the eyewear device, thereby to retain the lens in position on the eyewear body, the lens retainer element being disposable between a locked condition in which it retains a lens on the eyewear body, and a released condition in which it permits removal and replacement of the lens.
12 . The eyewear device of claim 10 , wherein the dipole conductor is incorporated in the eyewear body to extend along at least a part of the eyewear body.
13 . The eyewear device of claim 12 , wherein the eyewear body comprises a frame that defines a pair of lens holders for supporting respective lenses, at least part of the dipole conductor being incorporated in the frame to extend laterally across at least part of the frame, the dipole conductor being substantially tangential relative to the loop conductor that extends circumferentially around one of the lens holders, wherein the loop-shaped portion of the dipole conductor extends circumferentially along the lens holder other than the lens holder associated with the loop conductor.
14 . The eyewear device of claim 12 , wherein the dipole conductor comprises:
a main portion that is incorporated in a lens-holding frame defined by the eyewear body, the main portion lying substantially within a plane defined by the loop conductor; and
for at least one of the ends of the dipole conductor, an angled end portion that extends transversely relative to the plane of the loop conductor.
15 . The eyewear device of claim 14 , wherein the angled end portion of the dipole conductor defines a temple portion that is incorporated in and extends along a temple connected to the frame for supporting the frame during wear, the temple portion, when the eyewear device is in a wearable configuration, extending transversely to the plane of the loop conductor.
16 . The eyewear device of claim 9 , further comprising a diplexer connected to the non-loop conductor and to the loop conductor to provide frequency-domain multiplexing based on respective frequency domains of the loop conductor and the non-loop conductor.
17 . The eyewear device of claim 16 , wherein the respective conductors and the diplexer are configured such that the non-loop conductor serves as a GPS antenna, and the loop conductor serves as a data communication antenna, the frequency domain of the loop conductor being higher than the frequency domain of the non-loop conductor.