Self-powered reconfigurable intelligent surfaces with wireless power transfer
Provided herein are reconfigurable intelligent surfaces (RIS) including a surface, a source tile positioned on or proximate a first side of the surface and including a source power layer including a power amplifier and a transmitter coil configured to generate an electromagnetic field and a radio frequency (RF) layer configured to receive power from the source electromagnetic field, and a patch antenna grid for reflecting a RF signal, and a plurality of extender tiles positioned on or proximate the first side of the surface, the extender tiles each including an extender power layer including a passive transceiver coil for receiving the source electromagnetic field and relaying the source electromagnetic field as an extender electromagnetic field and an extender RF layer configured to receive power from the extender electromagnetic field, and an extender patch antenna grid for reflecting at least one of the RF signal or a second RF signal.
1. A reconfigurable intelligent surface (RIS) comprising:
a surface;
a source tile positioned on or proximate a first side of the surface and including:
a source power layer including a power amplifier and a transmitter coil configured to generate an electromagnetic field, and
a radio frequency (RF) layer configured to receive power from the source electromagnetic field, and a patch antenna grid for reflecting a RF signal; and
a plurality of extender tiles positioned on or proximate the first side of the surface, the extender tiles each including:
an extender power layer including a passive transceiver coil for receiving the source electromagnetic field and relaying the source electromagnetic field as an extender electromagnetic field, and
an extender RF layer configured to receive power from the extender electromagnetic field, and an extender patch antenna grid for reflecting at least one of the RF signal or a second RF signal,
wherein at least one of the RF layer and the extender RF layer further comprises:
a RF switch in electrical communication with each of the patch antenna grid and the extender patch antenna grid for varying an impedance of the patch antenna grid; or
a voltage rectifier; or
a DC-DC voltage converter; or
an integrated chip configured for controlling the battery; or
a combination thereof.
2. The RIS of claim 1 , wherein the patch antenna grid and the extender patch antenna grid each includes a plurality of patch antenna elements.
3. The RIS of claim 2 , wherein each patch antenna element is dimensioned at half a wavelength of a carrier frequency at each grid location.
4. The RIS of claim 2 , wherein each patch antenna element is spaced at half a wavelength of the carrier frequency at each grid location.
5. The RIS of claim 1 , wherein the magnetic resonance power amplifier is a Class-D amplifier operating at 6.78 MHz.
6. The RIS of claim 1 , wherein the transmitter coil includes a resonance PCB coil fabricated with FR-4 epoxy glass substrate as a 2-layer PCB in which two copper coils are placed at the RF and the power layers and connected as parallel.
7. The RIS of claim 1 , wherein:
the source tile is the only source tile positioned on or proximate the first side of the surface; and
the source tile is the only electrical source in electrical communication with the extender tiles.
8. The RIS of claim 1 , further comprising at least one additional source tile positioned on or proximate the first side of the surface.
9. The RIS of claim 1 , wherein at least one of the source electromagnetic field or the extender electromagnetic field is configured to transmit electrical power to one or more devices to be charged.
10. The RIS of claim 1 , wherein the RF layer is further configured to optionally receive power from a power source other than the source electromagnetic field.
11. A reconfigurable intelligent surface (RIS) comprising:
a surface;
a source tile positioned on or proximate a first side of the surface and including:
a source power layer including a power amplifier and a transmitter coil configured to generate an electromagnetic field, and
a radio frequency (RF) layer configured to receive power from the source electromagnetic field, and a patch antenna grid for reflecting a RF signal; and
a plurality of extender tiles positioned on or proximate the first side of the surface, the extender tiles each including:
an extender power layer including a passive transceiver coil for receiving the source electromagnetic field and relaying the source electromagnetic field as an extender electromagnetic field, and
an extender RF layer configured to receive power from the extender electromagnetic field, and an extender patch antenna grid for reflecting at least one of the RF signal or a second RF signal,
wherein at least one of the source power layer and the extender power layer includes:
a capacitor bank used to adjust impedance for forming power spots over the surface;
a low-power microcontroller for controlling configuration of resonators; or
a RF radio chip for sending and receiving messages between a respective source or extender tile and a power source; or
a combination thereof.
12. The RIS of claim 11 , wherein the RF radio chip is configured, by thread-based mesh networking, to create a resilient and low-power full-mesh network among the source tile and the extender tiles.
13. The RIS of claim 12 , wherein the resilient and low-power full-mesh network is configured to exchange control messages among the source tile and the extender tiles for real-time adjustment of coil impedances and coordination between RIS units.
14. The RIS of claim 13 , wherein the RF radio chip uses 6LowPAN and IEEE 802.15.4 for communication at 2.4 GHz frequency band.
15. A reconfigurable intelligent surface (RIS) comprising:
a surface;
a source tile positioned on or proximate a first side of the surface and including:
a source power layer including a power amplifier and a transmitter coil configured to generate an electromagnetic field, and
a radio frequency (RF) layer configured to receive power from the source electromagnetic field, and a patch antenna grid for reflecting a RF signal; and
a plurality of extender tiles positioned on or proximate the first side of the surface, the extender tiles each including:
an extender power layer including a passive transceiver coil for receiving the source electromagnetic field and relaying the source electromagnetic field as an extender electromagnetic field, and
an extender RF layer configured to receive power from the extender electromagnetic field, and an extender patch antenna grid for reflecting at least one of the RF signal or a second RF signal,
wherein:
the patch antenna grid further configured to alter at least one of a phase, an amplitude, or a directionality of the RF signal; and
the extender patch antenna grid further configured to alter at least one of a phase, an amplitude, or a directionality of the at least one of the RF signal or the second RF signal.
16. A reconfigurable intelligent surface (RIS) comprising:
a surface;
a source tile positioned on or proximate a first side of the surface and including:
a source power layer including a power amplifier and a transmitter coil configured to generate an electromagnetic field, and
a radio frequency (RF) layer configured to receive power from the source electromagnetic field, and a patch antenna grid for reflecting a RF signal; and
a plurality of extender tiles positioned on or proximate the first side of the surface, the extender tiles each including:
an extender power layer including a passive transceiver coil for receiving the source electromagnetic field and relaying the source electromagnetic field as an extender electromagnetic field, and
an extender RF layer configured to receive power from the extender electromagnetic field, and an extender patch antenna grid for reflecting at least one of the RF signal or a second RF signal,
wherein the RF signal and/or the second RF signal is a RF data signal.
17. The RIS of claim 16 , wherein the RF data signal is a mobile wireless signal.