Computer system for maximizing wireless energy harvesting using intelligent reflecting surface and method thereof

Patent metadata

Field	Value
Publication number	US-2023307948-A1
Application number	US-202217810478-A
Country	US
Kind code	A1
Filing date	Jul 1, 2022
Priority date	Mar 28, 2022
Publication date	Sep 28, 2023
Grant date	—

Abstract

The present disclosure relates to a computer system for maximizing wireless energy harvesting using an intelligent reflection surface and a method thereof. A multi-path channel including a direct channel through which power is directed from an ET apparatus toward an EU apparatus and a reflection channel through which the power is directed from the ET apparatus toward the EU apparatus after being reflected by an IRS apparatus may be implemented. The computer system may be designed to maximize a gain of the multi-path channel in order to maximize the harvested power.

First claim

1 . A computer system for wireless power transfer, comprising:
an energy transfer (ET) apparatus configured to transmit power as a wireless signal; an energy user (EU) apparatus configured to harvest power from a received signal; and an intelligent reflection surface (IRS) apparatus configured to reflect the signal from the ET apparatus to the EU apparatus, wherein in the computer system, a multi-path channel comprising a direct channel through which the power is directed from the ET apparatus toward the EU apparatus and a reflection channel through which the power is directed from the ET apparatus toward the EU apparatus after being reflected by the IRS apparatus is implemented, and wherein the computer system is designed to maximize a gain of the multi-path channel in order to maximize the harvested power.

2 . The method of claim 1 , wherein a transmission waveform of the transmitted signal is designed so that the transmitted signal is matched with the multi-path channel and peak amplitude is periodically generated from the received signal.

3 . The computer system of claim 2 , wherein the transmission waveform is designed based on a channel impulse response of the multi-path channel in a time domain.

4 . The computer system of claim 3 , wherein the transmission waveform is designed by disposing a channel impulse response of the multi-path channel in reverse order of time and performing conjugate-complex on the channel impulse response.

5 . The computer system of claim 2 , wherein the EU apparatus comprises an energy harvester output power of which is exponentially increased with respect to the power of the received signal, and harvests the output power, and
wherein the harvested power is maximized as the peak amplitude periodically occurs from the received signal.

6 . The computer system of claim 1 , wherein a reflection phase change value of the IRS apparatus is designed so that a phase of the reflection channel is aligned with a phase of the direct channel.

7 . The computer system of claim 6 , wherein a gain of the multi-path channel is increased as a phase difference between the phase of the reflection channel and the phase of the direct channel becomes small.

8 . The computer system of claim 6 , wherein amplitude of a peak component in the received signal is increased as the phase of the reflection channel and the phase of the direct channel are aligned, so that the gain of the multi-path channel is maximized.

9 . The computer system of claim 8 , wherein the ET apparatus comprises a plurality of transmission antennas.
wherein the IRS apparatus comprises a plurality of passive elements, and wherein the peak component of the received signal is represented in a form of a matrix vector product of a vector comprising an effective channel matrix between the transmission antennas and the EU apparatus and reflection coefficient vectors of the passive elements.

10 . The computer system of claim 9 , wherein the reflection coefficient vector is set by using a phase component of a dominant right singular vector of the effective channel matrix through singular vector decomposition.

11 . The computer system of claim 9 , wherein if the direct channel and the reflection channel are narrowband channels in the multi-path channel, a transmission waveform of the transmitted signal is modified into active beamforming of the ET apparatus, and the reflection coefficient vector be modified into passive beamforming of the IRS apparatus.

12 . A method of a computer system for wireless power transfer, the method comprising:
transmitting, by an energy transfer (ET) apparatus, power as a wireless signal; reflecting, by an intelligent reflection surface (IRS) apparatus, the signal from the ET apparatus; and harvesting, by an energy user (EU) apparatus, power from at least one of the ET apparatus or the IRS apparatus based on a received signal, wherein in the computer system, a multi-path channel comprising a direct channel through which the power is directed from the ET apparatus toward the EU apparatus and a reflection channel through which the power is directed from the ET apparatus toward the EU apparatus after being reflected by the IRS apparatus is implemented, and wherein the computer system is designed to maximize a gain of the multi-path channel in order to maximize the harvested power.

13 . The method of claim 12 , wherein a transmission waveform of the transmitted signal is designed so that the transmitted signal is matched with the multi-path channel and peak amplitude is periodically generated from the received signal.

14 . The method of claim 13 , wherein the transmission waveform is designed based on a channel impulse response of the multi-path channel in a time domain.

15 . The method of claim 14 , wherein the transmission waveform is designed by disposing a channel impulse response of the multi-path channel in reverse order of time and performing conjugate-complex on the channel impulse response.

16 . The method of claim 13 , wherein the EU apparatus comprises an energy harvester output power of which is exponentially increased with respect to the power of the received signal, and harvests the output power, and
wherein the harvested power is maximized as the peak amplitude periodically occurs from the received signal.

17 . The method of claim 12 , wherein a reflection phase change value of the IRS apparatus is designed so that a phase of the reflection channel is aligned with a phase of the direct channel.

18 . The method of claim 17 , wherein a gain of the multi-path channel is increased as a phase difference between the phase of the reflection channel and the phase of the direct channel becomes small.

19 . The method of claim 17 , wherein amplitude of a peak component in the received signal is increased as the phase of the reflection channel and the phase of the direct channel are aligned, so that the gain of the multi-path channel is maximized.

20 . The method of claim 19 , wherein the ET apparatus comprises a plurality of transmission antennas.
wherein the IRS apparatus comprises a plurality of passive elements, and wherein the peak component of the received signal is represented in a form of a matrix vector product of a vector comprising an effective channel matrix between the transmission antennas and the EU apparatus and reflection coefficient vectors of the passive elements.

Assignees

• Korea Advanced Inst Sci & Tech

Inventors

• Park Hyuncheol
• Hwang Min Young

Classifications

• H02J50/001 Primary

  Energy harvesting or scavenging · CPC title

• H02J50/40

  using two or more transmitting or receiving devices (H02J50/50 takes precedence) · CPC title

• H02J50/20 Primary

  using microwaves or radio frequency waves · CPC title