RF SIGNAL PICKUP FROM AN ELECTRICALLY CONDUCTIVE SUBSTRATE UTILIZING PASSIVE SLITS
Embodiments of the present application relate generally to electronic hardware, computer software, wireless communications, network communications, wearable, hand-held, and portable computing devices for facilitating communication of information and presentation of media. An electrically conductive substrate (e.g., a metal or metal alloy) includes an antenna formed by a slot or opening formed in the substrate, and also includes at least one separate passive slot or opening (e.g., a passive slit) formed in the substrate. The antenna may be intentionally detuned from one or more target frequencies (e.g., 802.11, 2.4 GHz, 5 GHz) such that the antenna is not optimized (e.g., is not tuned) for the one or more target frequencies. One portion of the antenna may be electrically coupled with a ground potential. Another portion of the antenna may be electrically coupled with a RF receiver, transmitter, or transceiver. The antenna may be an active antenna, a passive antenna or both.
1 . A device, comprising:
a substrate of electrically conductive material including a plurality of separate apertures formed in the substrate,
one or more of the plurality of separate apertures comprises an antenna having length dimension that is substantially larger than a width dimension, an edge of the aperture along the length dimension is electrically coupled with a radio frequency (RF) receiver and an opposing edge of the aperture along the length dimension is electrically coupled with a ground potential,
the length dimension is selected to detune the antenna at a frequency that is lower than a target frequency to be detected by the RF receiver, the length dimension being longer than a wavelength of the target frequency divided by two, and
a different one or more of the plurality of separate apertures comprises a passive slit that is not electrically coupled with the RF receiver or the ground potential.
2 . The device of claim 1 , wherein the antenna has a vertical polarization.
3 . The device of claim 1 , wherein a dielectric material is disposed in one or more of the plurality of separate apertures.
4 . The device of claim 3 , wherein the dielectric material comprises air.
5 . The device of claim 1 , wherein the passive slit has a length and a width that are less than the length dimension and width dimension, respectively of the antenna.
6 . The device of claim 1 , wherein different dielectric materials are disposed in at least two of the plurality of separate apertures.
7 . The device of claim 1 , wherein the target frequency comprises a frequency or frequency range selected from the group consisting of 2.4 GHz, 2.4 GHz-2.48 GHz, from about 2.4 GHz to about 2.48 GHz, 5 GHz, military frequency bands, unlicensed frequency bands, cellular frequency bands, and licensed frequency bands.
8 . The device of claim 1 , wherein the target frequency is in a range from about 2.4 GHz to about 2.48 GHz and the antenna is detuned to a range from about 0.5 MHz to about 1 GHz.
9 . The device of claim 1 , wherein the ground potential is a selected one of ground (GND) or a chassis ground.
10 . The device of claim 1 , wherein the substrate of electrically conductive material comprises at least a portion of a chassis or enclosure of an electrical device or system.
11 . The device of claim 1 and further comprising:
a functional element, an esthetic element, or both, formed from an electrically non-conductive material and positioned in at least a portion of one or more the plurality of separate apertures.
12 . The device of claim 1 , wherein the substrate of electrically conductive material comprises a metal or a metal alloy.
13 . The device of claim 1 , wherein the substrate of electrically conductive material comprises a perforate material.
14 . The device of claim 1 and further comprising at least two passive slits.
15 . A multi-channel dual band wireless communication and radio frequency (RF) proximity detection system, comprising:
circuitry configured to implement a 2×2 Multiple-Input/Multiple-Output (MIMO) mode and a 1×2 MIMO mode, the circuitry configured to reversibly switch between the 2×2 MIMO mode and the 1×2 MIMO mode in response to a mode signal electrically coupled with a RF switch, the circuitry including
a first RF chain electrically coupled with the RF switch and configured, when the mode signal is set to the 2×2 MIMO mode, to be electrically coupled through the RF switch with a first dual band antenna and to transmit and receive first and second dual band RF signals using the first dual band antenna, and
configured, when the mode signal is set to the 1×2 MIMO mode, to be electrically coupled through the RF switch with a RF proximity detection antenna and to receive only, using the RF proximity detection antenna, a fifth RF signal, and
a second RF chain electrically coupled with a second dual band antenna and configured, when the mode signal is set to the 2×2 MIMO mode or the 1×2 MIMO mode, to transmit and receive third and fourth dual band RF signals using the first dual band antenna.
16 . The system of claim 15 , wherein the RF proximity detection antenna comprises a substrate of an electrically conductive material including a plurality of separate apertures formed in the substrate, one or more of the separate apertures comprise passive slits that are electrically decoupled from the RF switch, and another one or more of the separate apertures comprises an antenna having a length edge electrically coupled with the RF switch and an opposing length edge electrically coupled with a ground potential.
17 . The system of claim 16 , wherein the antenna includes dimensions configured to detune the antenna below a target frequency.
18 . The system of claim 15 , wherein the RF proximity detection antenna is configured to generate the second RF signal in response to an external wireless device that transmits the fifth RF signal and is placed directly on, in near field proximity to, or in very close near field proximity to the RF proximity detection antenna.
19 . A radio frequency (RF) device, comprising:
an integrated circuit (IC) having circuitry including
RF circuitry configured to implement a 2×2 Multiple-Input/Multiple-Output (MIMO) mode and a 1×2 MIMO mode, the RF circuitry configured to reversibly switch between the 2×2 MIMO mode and the 1×2 MIMO mode in response to a mode signal electrically coupled with a RF switch,
a first RF chain electrically coupled with the RF switch and configured, when the mode signal is set to the 2×2 MIMO mode, to be electrically coupled through the RF switch with an external first dual band antenna and to transmit and receive, using the external first dual band antenna, first and second dual band RF signals, and
the first RF chain configured, when the mode signal is set to the 1×2 MIMO mode, to be electrically coupled through the RF switch with an external RF proximity detection antenna, and to receive only, using the external RF proximity detection antenna, a fifth RF signal, and
a second RF chain electrically coupled with an external second dual band antenna and configured to transmit and receive third and fourth dual band RF signals in the 1×2 or 2×2 MIMO modes.
20 . The device of claim 19 , wherein the external RF proximity detection antenna comprises a substrate of an electrically conductive material including a plurality of separate apertures formed in the substrate, one or more of the separate apertures comprise passive slits that are electrically decoupled from the RF switch, and another one or more of the separate apertures comprises an antenna having a length edge electrically coupled with the RF switch and an opposing length edge electrically coupled with a ground potential.