Radio signal pickup from an electrically conductive substrate utilizing passive slits
View Patent ↗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, such as a sheet of metal or metal alloy, for example, includes an active 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 active antenna may be intentionally detuned from one or more target frequencies (e.g., 802.11, 2.4 GHz, 5 GHz) such that the active antenna is not optimized (e.g., is not tuned) for the one or more target frequencies. One portion of the active antenna may be electrically coupled with a ground potential. Another portion of the active antenna may be electrically coupled with a RF receiver, transmitter, or transceiver.
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 active 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 active 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
another of the 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, the RF receiver, the active antenna, and the passive slit being configured as a detection system, the detection system being configured to detect a signal having another frequency above the target frequency, the signal being generated by a device placed in close proximity to the detection system.
2. The device of claim 1 , wherein the active 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 active 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 active 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.