Tunable cell for high-speed surface modulation
Aspects of the subject disclosure may include, for example, a group of controllable surface cells of an intelligent controllable surface, wherein the surface cells include input surfaces in communication with a waveguide and configured to receive an RF carrier signal via the waveguide. The controllable surface also includes a group of output surfaces and a group of control terminals in communication with the controllable surface cells and configured to receive an information signal. The intelligent controllable surface includes a group of controllable devices in communication with the control terminals, wherein the controllable devices are configured to control scattering parameters of the controllable surface cells responsive to the information signal to impress a direct modulation upon the RF carrier signal. Other embodiments are disclosed.
1 . A method, comprising:
guiding, via a waveguide or a transmission line, a radio frequency (RF) carrier signal towards an input surface of a first controllable surface cell of an intelligent controllable surface to obtain a guided RF carrier signal, wherein the waveguide or the transmission line directly couples a source of the RF carrier signal to the input surface of the first controllable surface cell, and wherein the first controllable surface cell comprises a first controllable device in communication with the input surface and an output surface;
obtaining a first information signal;
adjusting the first controllable device according to the first information signal to obtain a first controlled device, wherein a property of the first controllable surface cell is varied according to the first controlled device to obtain a first varied surface cell property;
modulating the guided RF carrier signal responsive to the first varied surface cell property to obtain a first modulated RF carrier signal; and
radiating the first modulated RF carrier signal via the output surface of the first controllable surface cell.
2 . The method of claim 1 , wherein the first varied surface cell property comprises a transmissivity property.
3 . The method of claim 2 , wherein variation of the transmissivity property produces a variation of at least one of an amplitude of the guided RF carrier signal, a phase of the guided RF carrier signal, or a combination thereof to obtain the first modulated RF signal.
4 . The method of claim 1 , wherein the first varied surface cell property comprises a reflectivity property.
5 . The method of claim 4 , wherein variation of the reflectivity property produces a variation of at least one of an amplitude or a phase of the guided RF carrier signal to obtain the first modulated RF signal.
6 . The method of claim 1 , wherein the first information signal comprises low-voltage differential signaling (LVDS).
7 . The method of claim 1 , wherein the RF carrier signal comprises a millimeter wave signal.
8 . The method of claim 1 , wherein adjusting the first controllable device further comprises tuning a tunable device.
9 . The method of claim 8 , wherein the tunable device comprises a passive semiconductor device, and wherein the tuning the tunable device further comprises adjusting one of a current, a voltage, or a combination thereof applied to the passive semiconductor device.
10 . The method of claim 8 , wherein the tuning the tunable device further comprises adjusting one of a current, a voltage, or a combination thereof applied to a varactor diode configured to tune a reactance of the first controllable surface cell responsive to the first information signal.
11 . The method of claim 1 , further comprising:
guiding the RF carrier signal towards an input surface of a second controllable surface cell comprising a second controllable device in communication with the input surface and an output surface;
providing a second control terminal in communication with the second controllable device, wherein the second control terminal is configured to receive a second information signal;
adjusting the second controllable device according to the second information signal to obtain a second controlled device, wherein a property of the second controllable surface cell is varied according to the second controlled device to obtain a second varied surface cell property;
modulating the RF carrier signal responsive to the second varied surface cell property to obtain a second modulated RF carrier signal; and
radiating the second modulated RF carrier signal via the output surface of the second controllable surface cell, wherein the output surface of the first controllable surface cell is adjacent to the second controllable surface cell.
12 . A device, comprising:
a radio frequency (RF) distributor configured to guide an RF carrier signal to obtain a guided RF carrier signal;
a plurality of controllable surface cells of an intelligent controllable surface comprising a plurality of input surfaces in communication with the RF distributor and exposed to the guided RF carrier signal and a plurality of output surfaces;
a plurality of tunable devices associated with the plurality of controllable surface cells, wherein the plurality of tunable devices is adapted to vary properties of the plurality of controllable surface cells;
a modulation controller in communication with the plurality of tunable devices, wherein the modulation controller is configured to modulate the guided RF carrier according to variation of the properties of the plurality of controllable surface cells to obtain a modulated RF carrier signal; and
a plurality of emitters in communication with the plurality of output surfaces, wherein the plurality of emitters is configured to radiate the modulated RF carrier signal.
13 . The device of claim 12 , wherein the plurality of controllable surface cells comprises a plurality of resonant structures.
14 . The device of claim 13 , wherein the plurality of tunable devices is configured to change resonant properties of the plurality of resonant structures in a predictable manner.
15 . The device of claim 12 , wherein the plurality of tunable devices comprises a plurality of varactor diodes configured to tune a plurality of reactance values of the plurality of controllable surface cells according to an information signal.
16 . The device of claim 12 , wherein the modulation controller is configured to modulate the guided RF carrier signal according to a direct modulation of the RF carrier signal.
17 . The device of claim 16 , wherein the direct modulation comprises one of an on-off-keying (OOK) modulation or a binary phase shift keying (BPSK) modulation.
18 . The device of claim 17 , the RF carrier signal comprises a millimeter wave carrier signal.
19 . An intelligent controllable surface, comprising:
a plurality of controllable surface cells of an intelligent controllable surface comprising a plurality of input surfaces in communication with a waveguide, the input surfaces configured to receive an RF carrier signal via the waveguide, and a plurality of output surfaces;
a plurality of control terminals in communication with the plurality of controllable surface cells, wherein the plurality of control terminals is configured to receive an information signal; and
a plurality of controllable devices in communication with the plurality of control terminals, wherein the plurality of controllable devices is configured to control scattering parameters of the plurality of controllable surface cells responsive to the information signal, wherein the scattering parameters impress a direct modulation upon the RF carrier signal to obtain a first modulated RF carrier signal.
20 . The intelligent controllable surface of claim 19 , wherein the scattering parameters comprise a reflective property and a transmissive property, and
wherein the plurality of controllable devices further comprises:
a first group of controllable devices configured to impress a first direct modulation upon the RF carrier according to the reflective property; and
a second group of controllable devices configured to impress a second direct modulation upon the RF carrier according to the transmissive property.