Antenna impedance stabilization with stabilization load in second antenna circuitry

摘要

There are first and second antennas proximally disposed and configured to resonate within respective first and second frequency bands, which may overlap. An impedance stabilization circuitry is coupled to ground. There is a selective coupler (for example, diplexer, directional coupler, switch) interfacing the second antenna selectively with the impedance stabilization circuitry and with radio circuitry. The selective coupler comprises a first port coupled to the second antenna, a second port coupled to the impedance stabilization circuitry, and a third port configured to couple with radio circuitry that is configured to operate in the second frequency band. The selective coupler provides a predetermined impedance to signals within the first frequency band and a low insertion loss to signals within the second frequency band, thus providing a stable impedance for the first antenna's view of the second antenna.

主权项

1. An apparatus comprising:
a first antenna configured to resonate within a first frequency band; a second antenna disposed proximal to the first antenna and configured to resonate in a second frequency band; impedance stabilization circuitry configurable to stabilize the impedance seen by the first antenna in the direction of the second antenna; and a selective coupler configured to couple to the second antenna selectively with the impedance stabilization circuitry and with radio circuitry, the selective coupler comprising a first port configured to couple to the second antenna, a second port configured to couple to the impedance stabilization circuitry, and a third port configured to couple with radio circuitry, the radio circuitry configured to operate in the second frequency band; the selective coupler configured to provide a predetermined impedance via the impedance stabilization circuitry to signals within the first frequency band and to provide a low insertion loss to signals within the second frequency band.