US 12,424,879 B2
Efficient transfer of power in a wireless power transfer system
Gang Zou, Lund (SE)
Assigned to Telefonaktiebolaget LM Ericsson (publ), Stockholm (SE)
Appl. No. 18/849,795
Filed by Telefonaktiebolaget LM Ericsson (publ), Stockholm (SE)
PCT Filed Feb. 24, 2023, PCT No. PCT/EP2023/054705
§ 371(c)(1), (2) Date Sep. 23, 2024,
PCT Pub. No. WO2023/180006, PCT Pub. Date Sep. 28, 2023.
Claims priority of application No. 2230088-3 (SE), filed on Mar. 24, 2022.
Prior Publication US 2025/0219453 A1, Jul. 3, 2025
Int. Cl. H02J 50/20 (2016.01); H02J 50/80 (2016.01)
CPC H02J 50/20 (2016.02) [H02J 50/80 (2016.02)] 9 Claims
OG exemplary drawing
 
1. A method of wirelessly transferring power by means of radiative coupling from a wireless power transmitter (WPTx) to a wireless power receiver (WPRx), the method being performed by the WPTx and comprising:
obtaining a set of conversion efficiency/input power relationships by, for each one of a plurality of different waveform types, obtaining for said each one of the different waveform types, a relationship between input signal power at the WPRx and efficiency of radiofrequency-to-direct current (RF-to-DC) conversion of the input signal power by the WPRx;
obtaining a prediction that indicates at what received signal power level a received transmission of power from the WPTx will be at the WPRx;
using the prediction of received signal power at the WPRx and the set of conversion efficiency/input power relationships to identify which one or more of the different waveform types satisfies a predetermined selection criterion and selecting one of the one or more identified waveform types; and
transmitting, from the WPTx, a wireless power transfer signal having the selected waveform type,
wherein the plurality of different waveforms types comprises:
a multi-tone signal having a constant phase distribution; and
a multi-tone signal having a random phase distribution.