Distributed wireless charging system and method
A distributed wireless radio frequency-based charging system includes hardware and software platforms. The hardware platform includes adaptive energy harvesters and programmable energy transmitters. The software platform manages the hardware profiles, resources (e.g., energy waveforms and transmission powers), schedules the beams of the energy transmitters, and switches between modes of wireless charging and data access point. This allows the energy transmitters to be configured adaptively based on the ambient energy availability, energy needs and number of energy-requesting devices in the network. Under the software control, the energy transmitters can cooperatively form focused beams of energy and power for transmission to energy harvesters in the energy-receiving devices, such as sensors, Internet of Things (IoT) enabled appliances, and mobile/wearable equipment. The energy harvesters can utilize the energy contained within the transmitted beams, as well as ambient RF sources, for directly powering their operation or charging a battery/capacitor for subsequent use.
1. A method for distributed wireless charging, comprising:
in a network comprising at least two spatially distributed energy transmitters, a plurality of energy receiving target devices, and a controller comprising one or more processors and memory, and machine readable instructions stored in the memory executable by the one or more processors, the steps of, at the controller:
receiving a communication from at least one energy receiving target device or from one of the energy transmitters comprising a need for energy by one or more of the energy receiving target devices;
transmitting to the at least two energy transmitters, instructions for wireless transmission of radio frequency (RF) energy from the at least two energy transmitters to form constructive interference at an identified energy receiving target device, wherein the at least two energy transmitters are operative to coordinate adjustment of one or more of a frequency, a phase, and a time of transmission of the RF energy to form constructive energy beams at the identified energy receiving target device; and
transmitting, to at least one of the energy transmitters, configuration commands to switch between an energy transmission mode and an active data communication mode, including an identification of the energy transmitter to switch modes, a schedule of switching modes, a duration in each mode, and a wireless data communication protocol for use in the active data communication mode;
wherein each of the energy transmitters comprises a software-defined radio operable to provide phase and frequency synchronizations and configurable by communications from the controller, and an antenna in communication with the software-defined radio, and each of the energy transmitters is switchable between the energy transmission mode and the active data communication mode using the wireless data communication protocol for the network;
wherein each of the energy transmitters further includes a command manager module, in communication with the software-defined radio, operative to receive and process commands from the controller.
2. The method of claim 1 , wherein each of the energy transmitters further includes a data manager module operative to exchange digital data packets with the controller and others of the energy transmitters and the energy receiving target devices according to the wireless data communication protocol when in the active data communication mode.
3. The method of claim 1 , wherein one or more of the energy transmitters further comprise a data access point or a gateway for the network.
4. The method of claim 1 , wherein the schedule of switching modes of the configuration commands transmitted by the controller to each of the energy transmitters, when combined with the configuration commands transmitted configured to each other of the energy transmitters, apportions energy transmission from the energy transmitters between multiple energy receiving target devices based on at least one of current energy levels of each energy receiving target device, a number of the energy receiving target devices, a location of the energy receiving target devices, and an estimated future energy demand.
5. An energy transmitter device comprising:
a software-defined radio operable to provide phase and frequency synchronizations;
an antenna in communication with the software-defined radio; and
a command manager module, in communication with the software-defined radio, operative to receive and process commands from an external controller, wherein the device is operative as a data access point or a gateway for a network;
wherein the device is switchable between the energy transmission mode and the active data communication mode using a wireless data communication protocol for the network;
an energy wave manager operative to adjust one or more of a frequency, a phase, and a time of transmission of RF energy to form constructive energy beams at an energy harvesting target device and is operative to optimize constructive interference at the energy harvesting target device in response to the feedback, by iteratively adjusting one or more of frequency, phase, or timing of the RF energy when in the energy transmission mode.
6. The device of claim 5 , further comprising:
a data manager module operative to exchange digital data packets with the external controller and other external energy transmitters devices, according to the wireless data communication protocol when in the active data communication mode.
7. The device of claim 5 , wherein, in the energy transmission mode, the command manager module is configured to receive commands from the external controller including a schedule of switching modes, the schedule configured to apportion energy transmission from the device between multiple energy receiving target devices based on at least one of current energy levels of each energy receiving target device, a number of the energy receiving target devices, a location of the energy receiving target devices, and an estimated future energy demand.
8. The device of claim 5 , further comprising at least two transceivers for operation simultaneously in the energy transmission mode and active data communications mode.