User-wearable devices with primary and secondary radiator antennas

摘要

A user-wearable device include a wireless transceiver, a primary radiator antenna and a secondary radiator antenna. The primary radiator antenna produces a first radio frequency (RF) radiation pattern when driven by the wireless transceiver, wherein the first RF radiation pattern is at least partially circularly polarized. The secondary radiator antenna, which is spaced apart from the primary radiator antenna, is configured to modify the first RF radiation pattern produced by the primary radiator antenna to thereby produce a second RF radiation pattern having increased RF radiation in a specific direction (e.g., away from the user's/wearer's skin) compared to the first RF radiation pattern. Inclusion of both the primary radiator antenna and the secondary radiator antenna increases an overall antenna efficiency (e.g., by about 3 dB) in the specific direction compared to if only the primary radiator antenna was included.

主权项

1. A user-wearable device, comprising:
a printed circuit board (PCB); a wireless transceiver; a primary radiator antenna that produces a first radio frequency (RF) radiation pattern when driven by the wireless transceiver, said primary radiator antenna comprising an electrically conductive trace located on or in the PCB; and a secondary radiator antenna spaced apart from the primary radiator antenna, said secondary radiator antenna comprising an electrically conductive continuous loop spaced apart from the PCB, and said secondary radiator antenna configured to modify the first RF radiation pattern produced by the primary radiator antenna to thereby produce a second RF radiation pattern having increased RF radiation in a specific direction compared to the first RF radiation pattern.