Method for charging electronic devices through radio frequency power transmission, radio frequency charging pad and storage medium

Abstract

The method includes detecting, via a wireless communication component of a near-field charging pad, that a receiver is within a threshold distance of the pad. In response to detecting that the receiver is within the threshold distance of the pad, the method includes determining whether the wireless power receiver has been placed on the pad. Based on determining that the receiver has been placed on the pad, the method includes selectively transmitting, by corresponding antenna elements included in a plurality of antenna regions, corresponding test power transfer signals having a first set of transmission characteristics until it is determined that a specific power transfer parameter associated with the transmission of the corresponding test power transfer signal by at least one specific antenna region of the plurality of antenna regions satisfies a power transfer criterion. Upon determining that the specific power transfer parameter satisfies the power transfer criterion, the method also includes transmitting, using at least one specific antenna region, a plurality of additional power transfer signals to the receiver, wherein each of the plurality of power transfer signals is transmitted with a second set of transmission characteristics that is different from the first set of transmission characteristics.

Description

Technical Field

[0001] Embodiments herein relate generally to antennas, software, and devices used in wireless power transfer systems, and more particularly to near-field radio frequency charging pads with adaptive loads to efficiently charge electronic devices at any location on the pad. Background Art

[0002] Conventional charging pads utilize induction coils to generate a magnetic field for charging a device. A user must typically place the device in a specific location on the charging pad and cannot move the device to a different location on the pad without interrupting or terminating charging of the device. For many users, this results in a frustrating experience because they may not be able to position the device in the correct location on the pad to begin charging the user's device.

[0003] Conventional charging pads also utilize components that are distributed across multiple different integrated circuits. This configuration results in processing delays that cause these charging pads to operate slower than users of these pads desire (e.g., wireless charging and adjustments made during wireless charging take longer). Summary of the invention

[0004] Therefore, there is a need for a wireless charging system (e.g., a radio frequency charging pad) that solves the problems identified above. To this end, a radio frequency charging pad is described herein that includes components that are efficiently arranged on a single integrated circuit, and the single integrated circuit manages the antenna of the radio frequency charging pad by selectively or sequentially activating antenna areas (e.g., one or more antennas or unit cell antennas grouped together, also referred to herein as antenna groups, of the radio frequency charging pad) to locate efficient antenna areas for transmitting wireless power to a receiver device located on the surface of the radio frequency charging pad. Such a system and method of using the same help eliminate user dissatisfaction with conventional charging pads. For example, by monitoring the energy transmitted while selectively activating antenna areas, such a system and method of using the same help eliminate wasted radio frequency power transmissions by ensuring that energy transmission is maximized at any point in time and at any location where a device may be placed on the radio frequency charging pad, thereby eliminating wasted transmissions that may not be efficiently received.

[0005] In the following description, reference is made to a radio frequency charging pad that includes various antenna regions. For the purposes of this description, an antenna region includes one or more transmit antennas of the radio frequency charging pad and may be controlled by a control integrated circuit (e.g., Figures 1A to 1B The RF power transmitter integrated circuit 160 of the present invention is individually addressed to each antenna area to allow each antenna area to be selectively activated to determine which antenna area can most efficiently transmit wireless power to the receiver. The RF charging pad is also interchangeably referred to herein as a near field charging pad, or more simply a charging pad.

[0006] (A1) In some embodiments, the method is performed at a near-field charging pad, wherein the near-field charging pad includes a wireless communication component (e.g., Figure 1A communication component 204), a plurality of antenna regions (eg, Figure 1B ), and one or more processors (e.g., Figure 1B and Figure 2A The method includes: detecting, via a wireless communication component, that the wireless power receiver is within a threshold distance of a near-field charging pad, and in response to detecting that the wireless power receiver is within the threshold distance of the near-field charging pad, determining whether the wireless power receiver has been placed on the near-field charging pad. The method further includes: selectively transmitting, by corresponding antenna elements included in a plurality of antenna regions, corresponding test power transfer signals having a first set of transmission characteristics in accordance with determining that the wireless power receiver has been placed on the near-field charging pad, until it is determined that a specific power transfer parameter associated with the transmission of the corresponding test power transfer signal by at least one specific antenna region of the plurality of antenna regions satisfies a power transfer criterion. The method further includes: transmitting, using the at least one specific antenna region, a plurality of additional power transfer signals to the wireless power receiver when the specific power transfer parameter is determined by the one or more processors to satisfy the power transfer criterion, wherein each of the plurality of additional power transfer signals is transmitted with a second set of transmission characteristics different from the first set of transmission characteristics.

[0007] (A2) In some embodiments of the method of A1, determining whether the wireless power receiver has been placed on the surface of the near-field charging pad includes: (i) using each of the multiple antenna areas to transmit the test power transfer signal, (ii) monitoring the amount of reflected power at the near-field charging pad when transmitting the test power transfer signal, and (iii) when the amount of reflected power meets a device detection threshold, determining that the wireless power receiver has been placed on the near-field charging pad.

[0008] (A3) In some embodiments of the method of A2, the amount of reflected power is measured at each antenna area of ​​the plurality of antenna areas.

[0009] (A4) In some embodiments of the method of any one of A2 to A3, the device detection threshold is established during a calibration process of the near-field charging pad.

[0010] (A5) In some embodiments of the method of A4, the device detection threshold is specific to the type of device coupled to the wireless power receiver, and the device detection threshold is selected by the one or more processors after detecting that the wireless power receiver is close to a near-field charging pad (for example, the wireless power receiver sends an information packet to the near-field charging pad, and the information packet includes information identifying the type of device coupled to the wireless power receiver).

[0011] (A6) In some embodiments of the method of any one of A1 to A5, each antenna area among the multiple antenna areas is used to perform selective transmission of a corresponding test power transmission signal. In addition, the method further includes: before determining that the power transfer parameters associated with the transmission of the corresponding test power transmission signal by at least one specific antenna area among the multiple antenna areas meet the power transfer criteria: (i) based on the transmission of each antenna area, updating the corresponding power transfer parameters associated with the transmission of the corresponding test power transmission signal by each corresponding antenna area, and (ii) based on the corresponding power transfer parameters associated with each antenna area, selecting two or more antenna areas including the at least one specific antenna area to transmit wireless power to the wireless power receiver.

[0012] (A7) In some embodiments of the method of A6, the method further includes: using each of the two or more antenna regions to transmit an additional test power transfer signal having a first set of transmission characteristics. In addition, determining that a specific power transfer parameter satisfies the power transfer criteria includes: determining that the specific power transfer parameter indicates that the specific antenna region is transmitting wireless power to the wireless power receiver more efficiently than other antenna regions in the two or more antenna regions.

[0013] (A8) In some embodiments of the method of any one of A6 to A7, determining that a specific power transfer parameter satisfies a power transfer standard also includes: determining that the specific power transfer parameter indicates that a first threshold power amount is transmitted to the wireless power receiver through the at least one specific antenna area, and the at least one specific antenna area is the only antenna area among the two or more antenna areas having a corresponding power transfer parameter indicating that the first threshold power amount is transmitted to the wireless power receiver.

[0014] (A9) In some embodiments of the method of any one of A6 to A8, determining that the specific power transfer parameters satisfy the power transfer criteria also includes determining that (i) no antenna region is transmitting the first threshold power amount to the wireless power receiver, and (ii) additional power transfer parameters associated with additional antenna regions of the two or more antenna regions satisfy the power transfer criteria. Additionally, the specific power transfer parameters indicate that a first power amount transmitted by the specific antenna region to the wireless power receiver is greater than a second threshold power amount and less than the first threshold power amount, and the additional power transfer parameters indicate that a second power amount transmitted by the additional antenna region to the wireless power receiver is greater than the second threshold power amount and less than the first threshold power amount.

[0015] (A10) In some embodiments of the method of A9, both the specific antenna group and the additional antenna group are used to simultaneously transmit additional multiple power transfer signals to provide power to the wireless power receiver.

[0016] (A11) In some embodiments of the method of any one of A1 to A10, information used to determine the power transfer parameter is provided by the wireless power receiver to the near-field charging pad via the wireless communication component of the near-field charging pad.

[0017] (A12) In some embodiments of the method of any one of A1 to A11, the second set of transmission characteristics is determined by adjusting at least one characteristic of the first set of transmission characteristics to increase the amount of power transmitted by a particular antenna group to the wireless power receiver.

[0018] (A13) In some embodiments of the method of A12, the at least one adjusted characteristic is a frequency or an impedance value.

[0019] (A14) In some embodiments of the method of any one of A1 to A13, when transmitting additional multiple power transfer signals, at least one characteristic in the second set of transmission characteristics is adjusted based on information received from the wireless power receiver, wherein the information is used to determine the power level wirelessly transmitted from the near-field charging pad to the wireless power receiver.

[0020] (A15) In some embodiments of the method of any of A1 to A14, the one or more processors are components of a single integrated circuit for controlling the operation of the near field charging pad. For example, any of the methods described herein is managed by a single integrated circuit, such as Figure 1B An example of a radio frequency (RF) power transmitter integrated circuit 160 is shown in FIG.

[0021] (A16) In some embodiments of the method of any one of items A1 to A15, each respective power transfer metric corresponds to an amount of power received by the wireless power receiver based on transmission of a respective test power transfer signal by a respective antenna group of the plurality of antenna groups.

[0022] (A17) In some embodiments of the method of any one of A1 to A16, the method further includes: before transmitting the test power transfer signal, determining that the wireless power receiver is authorized to receive wirelessly transmitted power from the near-field charging pad.

[0023] (A18) In another aspect, a near-field charging pad is provided. In some embodiments, the near-field charging pad includes a wireless communication component, a plurality of antenna regions each including at least one antenna element, one or more processors, and a memory storing one or more programs, wherein the one or more programs, when executed by the one or more processors, cause the near-field charging pad to perform the method described in any one of A1 to A17.

[0024] (A19) On the other hand, a near-field charging pad is provided, and the near-field charging pad includes a device for performing the method described in any one of A1 to A17.

[0025] (A20) In another aspect, a non-transitory computer-readable storage medium is provided. The non-transitory computer-readable storage medium stores executable instructions, which, when executed by a near-field charging pad (including a wireless communication component and a plurality of antenna regions each including at least one antenna element) using one or more processors / cores, cause the near-field charging pad to perform the method described in any one of A1 to A17.

[0026] As described above, there is also a need for a transmitter chip that includes components for managing wireless power transmission, all integrated on a single integrated circuit. Such a transmitter chip and method of using the same can help eliminate user dissatisfaction with conventional charging pads. By including all components on a single chip (as shown in the following reference Figure 1A and Figure 1B As discussed in more detail herein, such transmitter chips are able to manage operations at the transmitter chip more efficiently and quickly (and with lower latency), thereby helping to improve user satisfaction with charging pads managed by these transmitter chips.

[0027] (B1) In some embodiments, a transmitter chip includes: (i) a processing unit configured to control the operation of an integrated circuit; (ii) a power converter operably coupled to the processing unit and configured to convert an input current into radio frequency energy; (iii) a waveform generator operably coupled to the processing unit and configured to generate a plurality of power transmission signals using radio frequency energy; (iv) a first interface coupling the integrated circuit and a plurality of power amplifiers external to the integrated circuit; and (v) a second interface different from the first interface coupling the integrated circuit and a wireless communication component. The processing unit is further configured to: (i) receive an indication via the second interface that a wireless power receiver is within a transmission range of a near-field charging pad controlled by the transmitter chip, and (ii) in response to receiving the indication, provide at least some of the plurality of power transmission signals to at least one of the plurality of power amplifiers via the first interface.

[0028] (B2) In some embodiments of the transmitter chip of B1, the processing unit includes a CPU, a ROM, a RAM, and an encryption block (e.g., Figure 1B CPU subsystem 170).

[0029] (B3) In some embodiments of the transmitter chip of any one of B1 to B2, the input current is direct current. Alternatively, in some embodiments, the input current is alternating current. In these embodiments, the power converter is a radio frequency DC-DC converter or a radio frequency AC-AC converter, respectively.

[0030] (B4) In some embodiments of the transmitter chip of any of B1 to B3, the wireless communication component is a Bluetooth or Wi-Fi radio configured to receive communication signals from a device placed on the surface of the near-field charging pad.

[0031] To help solve the above problems and thereby provide a charging pad that meets the needs of users, the antenna area may include adaptive antenna elements (e.g., Figure 1B The antenna area 290 of the RF charging pad 100, each antenna area may include the following reference FIG. 3A to FIG. 6E and Figure 8 One or more of the antennas 120 described above) enable the charging pad to charge a device placed anywhere on the pad.

[0032] According to some embodiments, the antenna area of ​​the radio frequency (RF) charging pad described herein may include one or more antenna elements that communicate with the one or more processors and are used to transmit radio frequency signals to a radio frequency receiver of an electronic device. In some embodiments, each corresponding antenna element includes: (i) a conductive line that forms a meander line pattern; (ii) a first terminal that is at a first end of the conductive line and is used to receive a current flowing through the conductive line at a frequency controlled by the one or more processors; and (iii) a second terminal different from the first terminal, the second terminal is at a second end of the conductive line, and the second terminal is coupled to a component controlled by the at least one processor and allows the impedance value at the second terminal to be modified. In some embodiments, the at least one processor is configured to adaptively adjust the frequency and / or impedance value to optimize the amount of energy (energy amount) transmitted from the one or more antenna elements to the radio frequency receiver of the electronic device.

[0033] There is a need for a wireless charging system (e.g., a radio frequency charging pad) that includes adaptive antenna elements that can adjust energy transfer characteristics (e.g., impedance and frequency of the conductive lines of the corresponding antenna elements) so that the charging pad can charge a device placed anywhere on the pad. In some embodiments, these charging pads include one or more processors that monitor energy transfer from a transmitting antenna element (also referred to herein as a radio frequency antenna element or antenna element) and to a receiver of an electronic device to be charged, and the one or more processors optimize the energy transfer characteristics to maximize energy transfer at any location on the charging pad. Some embodiments may also include a feedback loop for reporting the received power at the receiver to the one or more processors.

[0034] (C1) According to some embodiments, a radio frequency (RF) charging pad is provided. The RF charging pad includes: at least one processor, the at least one processor is used to monitor the amount of energy transmitted from the RF charging pad to the RF receiver of the electronic device. The RF charging pad also includes: one or more antenna elements, the one or more antenna elements communicate with the one or more processors and are used to transmit radio frequency signals to the RF receiver of the electronic device. In some embodiments, each corresponding antenna element includes: (i) a conductive line, the conductive line forming a meander line pattern; (ii) a first terminal, the first terminal is at a first end of the conductive line and is used to receive a current flowing through the conductive line at a frequency controlled by the one or more processors; and (iii) a second terminal different from the first terminal, the second terminal is at a second end of the conductive line, and the second terminal is coupled to a component controlled by the at least one processor and allows the impedance value at the second terminal to be modified. In some embodiments, the at least one processor is configured to adaptively adjust the frequency and / or impedance value to optimize the amount of energy transmitted from the one or more antenna elements to the RF receiver of the electronic device.

[0035] (C2) According to some embodiments, a method for charging an electronic device via radio frequency (RF) power transmission is also provided. The method includes: providing a transmitter including at least one RF antenna. The method also includes: transmitting one or more RF signals via the at least one RF antenna, and monitoring the amount of energy transmitted from the at least one RF antenna to the RF receiver via the one or more RF signals. The method further includes: adaptively adjusting the characteristics of the transmitter to optimize the amount of energy transmitted from the at least one RF antenna to the RF receiver. In some embodiments, the characteristics are selected from the group consisting of: (i) the frequency of the one or more RF signals, (ii) the impedance of the transmitter, and (iii) a combination of (i) and (ii). In some embodiments, the at least one RF antenna is part of an RF antenna array.

[0036] (C3) According to some embodiments, a radio frequency (RF) charging pad is provided. The RF charging pad includes: one or more processors, the one or more processors being used to monitor the amount of energy transmitted from the RF charging pad to an RF receiver of an electronic device. The RF charging pad also includes: one or more transmitting antenna elements, the one or more transmitting antenna elements being configured to communicate with the one or more processors and to transmit RF signals to the RF receiver of the electronic device. In some embodiments, each respective antenna element includes: (i) a conductive line, the conductive line forming a meander line pattern; (ii) an input terminal, the input terminal being at a first end of the conductive line and being used to receive a current flowing through the conductive line at a frequency controlled by the one or more processors; and (iii) a plurality of adaptive load terminals different from the input terminal and different from each other, the plurality of adaptive load terminals being at a plurality of positions on the conductive line, each respective adaptive load terminal of the plurality of adaptive load terminals being coupled to a respective component configured to be controlled by the one or more processors and configured to allow modification of a respective impedance value at the respective adaptive load terminal. In some embodiments, the one or more processors are configured to adaptively adjust at least one of the frequency and the corresponding impedance value at one or more of the plurality of adaptive load terminals to optimize the amount of energy transmitted from the one or more transmitting antenna elements to the RF receiver of the electronic device.

[0037] (C4) According to some embodiments, a method for charging an electronic device by radio frequency (RF) power transmission is also provided. The method includes: providing a charging pad including a transmitter, the transmitter including one or more radio frequency antennas. In some embodiments, each radio frequency antenna includes: (i) a conductive line, the conductive line forming a meander line pattern; (ii) an input terminal, the input terminal is at a first end of the conductive line and is used to receive a current flowing through the conductive line at a frequency controlled by one or more processors; and (iii) a plurality of adaptive load terminals different from the input terminal and different from each other, the plurality of adaptive load terminals are at multiple positions of the conductive line, and each corresponding adaptive load terminal of the plurality of adaptive load terminals is coupled to a corresponding component configured to be controlled by the one or more processors and allows modification of a corresponding impedance value at the corresponding adaptive load terminal. The method also includes: transmitting one or more radio frequency signals via the one or more radio frequency antennas, and monitoring the amount of energy transmitted from the one or more radio frequency antennas to the radio frequency receiver via the one or more radio frequency signals. The method further includes: using the one or more processors of the transmitter to adaptively adjust the characteristics of the transmitter to optimize the amount of energy transmitted from the one or more radio frequency antennas to the radio frequency receiver. In some embodiments, the characteristic is selected from the group consisting of: (i) frequency of the one or more RF signals, (ii) impedance of the transmitter, and (iii) a combination of (i) and (ii). In some embodiments, the impedance of the transmitter is adaptively adjusted using the one or more processors of the transmitter at corresponding one or more adaptive load terminals of the plurality of adaptive load terminals of the one or more RF antennas.

[0038] (C5) According to some embodiments, a non-transitory computer-readable storage medium is provided. The non-transitory computer-readable storage medium includes executable instructions that, when executed by one or more processors coupled to a radio frequency (RF) charging pad including one or more transmitting antenna elements, cause the one or more processors to: monitor the amount of energy transmitted from the RF charging pad to an RF receiver of an electronic device; and communicate with the one or more transmitting antenna elements for transmitting RF signals to the RF receiver of the electronic device. In some embodiments, each respective transmitting antenna element includes: a conductive line, the conductive line forming a meander line pattern; an input terminal, the input terminal at a first end of the conductive line and for receiving a current flowing through the conductive line at a frequency controlled by the one or more processors; and a plurality of adaptive load terminals different from the input terminal and different from each other, the plurality of adaptive load terminals at a plurality of positions on the conductive line, each respective adaptive load terminal of the plurality of adaptive load terminals being coupled to a respective component configured to be controlled by the one or more processors and configured to allow modification of a respective impedance value at each respective adaptive load terminal. Furthermore, the one or more processors further adaptively adjust at least one of the frequency and the corresponding impedance value at one or more of the plurality of adaptive load terminals to optimize the amount of energy transmitted from the one or more transmitting antenna elements to the RF receiver of the electronic device.

[0039] (C6) In some embodiments of any one of items C1 to C5, the frequency is in a first frequency band, and at least one of the one or more transmitting antenna elements is configured to operate in a second frequency band based on adaptive adjustment by the one or more processors of corresponding impedance values ​​at one or more of the multiple adaptive load terminals of the at least one transmitting antenna element.

[0040] (C7) In some embodiments of any one of C1 to C6, the RF charging pad includes an input circuit coupled to the one or more processors and configured to provide current to the input terminal at the first end of the conductive wire, wherein the one or more processors are configured to adaptively adjust the frequency by instructing the input circuit to generate a current having a new frequency different from the frequency.

[0041] (C8) In some embodiments of any one of C1 to C7, the one or more processors are configured to adaptively adjust the frequency by instructing the feeding element to generate current having a plurality of different frequencies determined using predetermined increments.

[0042] (C9) In some embodiments of any one of C1 to C8, a corresponding conductive line for at least one of the one or more transmitting antenna elements has a corresponding meander line pattern, and the corresponding meander line pattern allows the at least one transmitting antenna element to efficiently transmit radio frequency signals having the frequency and / or the new frequency, at least two adjacent segments of the corresponding conductive line having the corresponding meander line pattern have different geometric dimensions relative to each other, and when the at least one transmitting antenna element is configured to transmit radio frequency signals having the frequency and / or the new frequency, the corresponding conductive line has a length that remains the same.

[0043] (C10) In some embodiments of any one of C1 to C9, at least one of the one or more transmitting antenna elements has a first segment and a second segment, the first segment includes the input terminal, and the at least one transmitting antenna element is configured to: operate at the frequency when the first segment is not coupled to the second segment, and operate at the new frequency when the first segment is coupled to the second segment; and the one or more processors are configured to couple the first segment to the second segment and simultaneously instruct the feed element to generate a current having the new frequency different from the frequency.

[0044] (C11) In some embodiments of any one of items C1 to C10, the one or more processors are configured to: adaptively adjust the frequency and / or corresponding impedance value associated with a first transmitting antenna element of the one or more transmitting antenna elements so that the first transmitting antenna element operates in a first frequency band; and adaptively adjust the frequency and / or corresponding impedance value associated with a second transmitting antenna element of the one or more transmitting antenna elements so that the second transmitting antenna element operates in a second frequency band, wherein the first frequency band is different from the second frequency band.

[0045] (C12) In some embodiments of any one of C1 to C11, the electronic device is placed in contact with or close to a top surface of the RF charging pad.

[0046] (C13) In some embodiments of any one of items C1 to C12, the corresponding component is a mechanical relay coupled to the corresponding adaptive load terminal for switching the corresponding adaptive load terminal between an open circuit state and a short circuit state, and the impedance value is adaptively adjusted at the corresponding adaptive load terminal of the corresponding transmitting antenna element by opening or closing the mechanical relay to switch between an open circuit or a short circuit, respectively.

[0047] (C14) In some embodiments of any one of C1 to C13, the corresponding component is an application specific integrated circuit (ASIC), and the corresponding impedance value is adaptively adjusted by the ASIC within a range of values.

[0048] (C15) In some embodiments of any one of C1 to C14, the one or more processors are configured to: adaptively adjust the frequency and / or the corresponding impedance value at one or more of the multiple adaptive load terminals to determine the relative maximum amount of energy transmitted to the RF receiver of the electronic device, and once the maximum amount of energy is determined, cause each of the one or more transmitting antenna elements to transmit a RF signal at a corresponding frequency and using a corresponding impedance value that results in the maximum amount of energy transmitted to the RF receiver.

[0049] (C16) In some embodiments of any one of C1 to C15, the one or more processors monitor the amount of energy transmitted to the RF receiver based at least in part on information received from the electronic device, wherein the information identifies the energy received from the RF signal at the RF receiver.

[0050] (C17) In some embodiments of any one of C1 to C16, the information identifying the received energy received from the electronic device is sent using a wireless communication protocol.

[0051] (C18) In some embodiments of any one of C1 to C17, the wireless communication protocol is Bluetooth Low Energy (BLE).

[0052] (C19) In some embodiments of any one of C1 to C18, the one or more processors monitor the amount of energy delivered based at least in part on the amount of energy detected at the corresponding adaptive load terminal.

[0053] Thus, a wireless charging system configured according to the principles described herein is capable of charging an electronic device anywhere it is placed on a radio frequency charging pad and avoids wasting energy by ensuring that energy transfer is constantly optimized.

[0054] In addition, a wireless charging system configured according to the principles described herein is capable of charging different electronic devices tuned to different frequencies or frequency bands on the same charging transmitter. In some embodiments, a transmitter with a single antenna element can operate at multiple frequencies or frequency bands at the same time or at different times. In some embodiments, a transmitter with multiple antenna elements can operate at multiple frequencies or frequency bands at the same time. This allows for greater flexibility in the type and size of antennas included in the receiving device.

[0055] Note that the above embodiments may be combined with any other embodiments described herein. The features and advantages described in the specification are not all inclusive, and in particular, many additional features and advantages will be apparent to those of ordinary skill in the art based on the drawings, description, and claims. In addition, it should be noted that the language used in the specification is primarily selected for readability and instructional purposes, and is not intended to define or restrict the subject matter of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Therefore, the present disclosure can be understood in more detail and a more specific description can be obtained by referring to the features of various embodiments, some of which are illustrated in the accompanying drawings. However, the drawings only illustrate the relevant features of the present disclosure and are therefore not to be considered limiting, as the description may admit other effective features.

[0057] Figure 1A is a block diagram of a radio frequency wireless power transfer system according to some embodiments.

[0058] Figure 1B is a block diagram illustrating components of an example RF charging pad including an RF power transmitter integrated circuit and an antenna area according to some embodiments.

[0059] Figure 2A is a block diagram illustrating an example radio frequency charging pad in accordance with some embodiments.

[0060] Figure 2B is a block diagram illustrating an example receiver device in accordance with some embodiments.

[0061] Figure 3A is a high-level block diagram of a radio frequency charging pad according to some embodiments.

[0062] Figures 3B to 3C is a high-level block diagram illustrating a portion of a radio frequency charging pad according to some embodiments.

[0063] Figure 3D is a block diagram of a simplified circuit illustrating energy flow within a portion of an antenna element that is transmitting a radio frequency signal in accordance with some embodiments.

[0064] Figure 4 is a schematic diagram of a transmit antenna element having two terminals according to some embodiments.

[0065] Figure 5 is a flow chart of a method for charging an electronic device via radio frequency (RF) power transfer.

[0066] Figures 6A to 6E is a schematic diagram illustrating various configurations of a single antenna element within a radio frequency charging pad according to some embodiments.

[0067] Figures 7A to 7D is a schematic diagram of an antenna element for a radio frequency receiver according to some embodiments.

[0068] Figure 8 is a schematic diagram of a radio frequency charging pad having multiple transmit antenna elements (or unit cells) according to some embodiments.

[0069] Figures 9A to 9B is a flow chart illustrating a method 900 of selectively activating one or more antenna regions in a near field charging pad in accordance with some embodiments.

[0070] Fig.10 is an overview showing a process for selectively activating one or more antenna regions in a near field charging pad in accordance with some embodiments.

[0071] Figures 11A to 11E is a flow chart illustrating aspects of selectively activating one or more antenna regions in a near field charging pad in accordance with some embodiments.

[0072] Fig.12 is a schematic diagram of a transmit antenna element with multiple adaptive loads of a radio frequency charging pad according to some embodiments.

[0073] Fig.13 is a flow chart of a method for charging an electronic device through radio frequency (RF) power transfer using at least one radio frequency antenna having a plurality of adaptive loads according to some embodiments.

[0074] Figures 14A to 14D is a schematic diagram illustrating various configurations of a single antenna element that may operate at multiple frequencies or bands within a radio frequency charging pad in accordance with some embodiments.

[0075] Fig.15 is a diagram illustrating an example configuration of a single antenna element that can operate at multiple frequencies or frequency bands by adjusting the length of the antenna element in accordance with some embodiments.

[0076] As a matter of practice, the various features illustrated in the drawings may not be drawn to scale. Therefore, the sizes of the various features may be arbitrarily enlarged or reduced for clarity. In addition, some drawings may not depict all components of a given system, method, or device. Finally, throughout the specification and drawings, the same reference numerals may be used to represent the same features. DETAILED DESCRIPTION

[0077] Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings. In the following detailed description, many specific details are set forth in order to provide a comprehensive understanding of the described embodiments. However, it will be apparent to one of ordinary skill in the art that the described embodiments may be practiced without these specific details. In other examples, well-known methods, procedures, components, circuits, and networks are not described in detail to prevent unnecessary obscurity of the various aspects of the embodiments.

[0078] Figure 1A is a block diagram of a radio frequency wireless power transmission system according to some embodiments. In some embodiments, the radio frequency wireless power transmission system 150 includes a radio frequency charging pad 100 (also referred to herein as a near field (NF) charging pad 100 or a radio frequency charging pad 100). In some embodiments, the radio frequency charging pad 100 includes a radio frequency power transmitter integrated circuit 160 (described in more detail below). In some embodiments, the following reference Figure 2A The RF charging pad 100 discussed in more detail includes one or more communication components 204 (e.g., wireless communication components such as WI-FI or Bluetooth radios). In some embodiments, the RF charging pad 100 is also connected to one or more power amplifier units 108-1, ... 108-N to control the one or more power amplifier units in driving the external TX antenna array 210 (e.g., Figure 2A In some embodiments, the RF power is controlled and modulated at the RF charging pad 100 via the switching circuit system so that the RF wireless power transmission system can send RF power to one or more wireless receiving devices via the TX antenna array 210. Example power amplifier units are described below with reference to Figure 3A Further detailed discussion.

[0079] In some embodiments, the communication component(s) 204 enable communication between the RF charging pad 100 and one or more communication networks. In some embodiments, the communication component(s) 204 are capable of communicating data using any of a variety of custom or standard wireless protocols (e.g., IEEE 802.15.4, Wi-Fi, ZigBee, 6LoWPAN, Thread, Z-Wave, Bluetooth Smart, ISA100.11a, WirelessHART, MiWi, etc.), custom or standard wired protocols (e.g., Ethernet, HomePlug, etc.), and / or any other suitable communication protocols including those not yet developed as of the filing date of this document.

[0080] Figure 1B1 is a block diagram of an RF power transmitter integrated circuit 160 ("IC") according to some embodiments. In some embodiments, the IC 160 includes a CPU subsystem 170, an external device control interface, an RF subsection for DC to RF power conversion, and analog and digital control interfaces interconnected via an interconnect component such as a bus or interconnect fabric block 171. In some embodiments, the CPU subsystem 170 includes a microprocessor unit (CPU) 202 with an associated read-only memory (ROM) 172 for controlling the RF power via a digital control interface (e.g., I 2 C port) boots the device program to an external flash memory (FLASH) that contains the program that is loaded into the CPU subsystem random access memory (RAM) 174 (e.g., Figure 2A In some embodiments, the CPU subsystem 170 also includes an encryption module or block 176 for authenticating and protecting communication exchanges with external devices, such as wireless power receivers intended to receive wirelessly delivered power from the RF charging pad 100.

[0081] In some embodiments, executable instructions running on a CPU (such as in Figure 2A The CPU subsystem 170 includes a memory 206 (shown in the memory 206 in FIG. 1 and described below) for managing the operation of the RF charging pad 100 and controlling external devices through control interfaces (e.g., SPI control interface 175) and other analog and digital interfaces included in the RF power transmitter integrated circuit 160. In some embodiments, the CPU subsystem also manages the operation of the RF sub-portion of the RF power transmitter integrated circuit 160, including the RF local oscillator (LO) 177 and the RF transmitter (TX) 178. In some embodiments, the RF local oscillator 177 is adjusted based on instructions from the CPU subsystem 170 and is thereby set to different desired operating frequencies, while the RF transmitter converts, amplifies, and modulates the RF output as desired to generate a feasible RF power level.

[0082] In some embodiments, the RF power transmitter integrated circuit 160 provides a feasible RF power level (e.g., via the RF transmitter 178) to an optional beamforming integrated circuit (IC) 109, which then provides a phase-shifted signal to one or more power amplifiers 108. In some embodiments, the beamforming integrated circuit 109 is used to ensure that a power transfer signal transmitted to a specific wireless power receiver using two or more antennas 210 (e.g., each antenna 210 may be associated with a different antenna region 290 or each antenna may belong to a single antenna region 290) is transmitted with appropriate characteristics (e.g., phase) to ensure that the power transmitted to the specific wireless power receiver is maximized (e.g., the power transfer signal arrives at the specific wireless power receiver in phase). In some embodiments, the beamforming integrated circuit 109 forms part of the RF power transmitter integrated circuit 160.

[0083] In some embodiments, the RF power transmitter integrated circuit 160 provides feasible RF power levels directly to one or more power amplifiers 108 (e.g., via the RF transmitter 178) and does not use the beamforming integrated circuit 109 (or bypasses the beamforming integrated circuit if no phase shift is required, such as when only a single antenna 210 is used to transmit a power transfer signal to a wireless power receiver).

[0084] In some embodiments, one or more power amplifiers 108 then provide RF signals to the antenna regions 290 for transmission to wireless power receivers that are authorized to receive the wirelessly delivered power from the RF charging pad 100. In some embodiments, each antenna region 290 is coupled to a corresponding PA 108 (e.g., antenna region 290-1 is coupled to PA 108-1, and antenna region 290-N is coupled to PA 108-N). In some embodiments, multiple antenna regions are each coupled to the same set of PAs 108 (e.g., all PAs 108 are coupled to each antenna region 290). Various arrangements and couplings of PAs 108 to antenna regions 290 allow the RF charging pad 100 to sequentially or selectively activate different antenna regions in order to determine the most efficient antenna region 290 for transmitting wireless power to a wireless power receiver (as described below with reference to FIG. 1 ). FIG. 9A to FIG. 9B , Fig.10 and FIG. 11A to FIG. 11E In some embodiments, the one or more power amplifiers 108 also communicate with the CPU subsystem 170 to allow the CPU 202 to measure the output power provided by the PA 108 to the antenna area of ​​the RF charging pad 100.

[0085] Figure 1BIt is also shown that in some embodiments, the antenna area 290 of the RF charging pad 100 may include one or more antennas 210A to 210N. In some embodiments, each of the multiple antenna areas includes one or more antennas 210 (e.g., antenna area 290-1 includes one antenna 210-A, and antenna area 290-N includes multiple antennas 210). In some embodiments, the multiple antennas included in each antenna area are dynamically defined based on various parameters (such as the location of the wireless power receiver on the RF charging pad 100). In some embodiments, the antenna area may include one or more of the meandering line antennas described in more detail below. In some embodiments, each antenna area 290 may include different types of antennas (e.g., meandering line antennas and loop antennas), while in other embodiments, each antenna area 290 may include a single antenna of the same type (e.g., all antenna areas 290 include a meandering line antenna), and in some other embodiments, the antenna area may include some antenna areas including single antennas of the same type and some antenna areas including different types of antennas. The antenna areas are also described in further detail below.

[0086] In some embodiments, the RF charging pad 100 may also include a temperature monitoring circuit that communicates with the CPU subsystem 170 to ensure that the RF charging pad 100 is maintained within an acceptable temperature range. For example, if it is determined that the RF charging pad 100 has reached a threshold temperature, the operation of the RF charging pad 100 may be temporarily suspended until the RF charging pad 100 drops below the threshold temperature.

[0087] By including the RF power transmitter circuit 160 ( Figure 1B ) shown, such transmitter chips are able to manage operations at the transmitter chips more efficiently and quickly (and with lower latency), thereby helping to improve user satisfaction with charging pads managed by these transmitter chips. For example, the RF power transmitter circuit 160 is cheaper to construct, has a smaller physical footprint, and is easier to install. In addition, and as described below with reference Figure 2A As explained in more detail, the RF power transmitter circuit 160 may also include a security element module 234 (e.g., included in Figure 1B ), the security element module 234 and the security element module 282 ( Figure 2B ) or receiver 104 to ensure that only authorized receivers can receive data from the RF charging pad 100 ( Figure 1B ) receives power transmitted wirelessly.

[0088] Figure 2A1 is a block diagram illustrating certain components of the RF charging pad 100 according to some embodiments. In some embodiments, the RF charging pad 100 includes an RF power transmitter integrated circuit 160 (and components included in the power transmitter integrated circuit, such as those described above with reference to FIG. Figure 1A to Figure 1B those described above), memory 206 (which may be included as part of the RF power transmitter integrated circuit 160, such as non-volatile memory 206 as part of the CPU subsystem 170), and one or more communication buses 208 for interconnecting these components (sometimes referred to as a chipset). In some embodiments, the RF charging pad 100 includes one or more sensors 212 (discussed below). In some embodiments, the RF charging pad 100 includes one or more output devices, such as one or more indicator lights, a sound card, a speaker, and a small display for displaying text messages and error codes. In some embodiments, the RF charging pad 100 includes a location detection device for determining the location of the RF charging pad 100, such as a GPS (global positioning satellite) or other geo-location receiver.

[0089] In some embodiments, the one or more sensors 212 include one or more thermal radiation sensors, ambient temperature sensors, humidity sensors, IR sensors, occupancy sensors (e.g., RFID sensors), ambient light sensors, motion detectors, accelerometers, and / or gyroscopes.

[0090] Memory 206 includes high-speed random access memory, such as DRAM, SRAM, DDR SRAM, or other random access solid-state memory devices; and optionally, includes non-volatile memory, such as one or more magnetic disk storage devices, one or more optical disk storage devices, one or more flash memory devices, or one or more other non-volatile solid-state storage devices. Memory 206 or alternatively non-volatile memory within memory 206 includes non-transitory computer-readable storage media. In some embodiments, memory 206 or non-transitory computer-readable storage media of memory 206 stores the following programs, modules, and data structures, or subsets or supersets thereof:

[0091] Operational logic 216, including processes for handling various basic system services and for performing hardware-related tasks; Communication module 218, for coupling to and / or communicating with remote devices (e.g., remote sensors, transmitters, receivers, servers, mapped storage, etc.) in conjunction with wireless communication component(s) 204;

[0092] A sensor module 220 for obtaining and processing sensor data (e.g., in conjunction with sensor(s) 212) to determine, for example, the presence, velocity, and / or location of objects in the vicinity of the RF charging pad 100;

[0093] A power waveform generation module 222 for generating and transmitting a power transfer signal (e.g., in conjunction with antenna regions 290 and antennas 210 included in the antenna regions, respectively), including but not limited to forming (a plurality of) energy pockets at a given location. The power waveform generation module 222 may also be used to modify the transmission characteristics for transmitting a power transfer signal through a single antenna region; and

[0094] Database 224, including but not limited to:

[0095] o sensor information 226 for storing and managing data received, detected, and / or transmitted by one or more sensors (e.g., sensor 212 and / or one or more remote sensors);

[0096] o device settings 228 for storing operating settings for the RF charging pad 100 and / or one or more remote devices;

[0097] o Communication protocol information 230 for storing and managing protocols for one or more protocols (e.g., custom or standard wireless protocols, such as ZigBee, Z-Wave, etc., and / or custom or standard wired protocols, such as Ethernet)

[0098] information; and

[0099] o Mapping data 232 for storing and managing mapping data (e.g., mapping one or more transmission fields); • Secure element module 234 for determining whether the wireless power receiver is authorized to receive wirelessly delivered power from the RF charging pad 100; and

[0100] Antenna region selection and tuning module 237 for coordinating the process of transmitting a test power transfer signal using various antenna regions to determine which antenna region or regions should be used to wirelessly transfer power to each wireless power receiver (see below for reference) FIG. 9A to FIG. 9B , Fig.10 ,and FIG. 11A to FIG. 11E explained in more detail).

[0101] Each of the above-identified elements (e.g., modules stored in the memory 206 of the RF charging pad 100) is optionally stored in one or more of the aforementioned memory devices and corresponds to a set of instructions for performing the above-identified (multiple) functions. The above-identified modules or programs (e.g., instruction sets) need not be implemented as independent software programs, processes, or modules, and thus various subsets of these modules are optionally combined or otherwise rearranged in various embodiments. In some embodiments, the memory 206 optionally stores a subset of the above-identified modules and data structures.

[0102] Figure 2B 1 is a block diagram illustrating a representative receiver device 104 (sometimes also referred to as a receiver, power receiver, or wireless power receiver) according to some embodiments. In some embodiments, the receiver device 104 includes one or more processing units 252 (e.g., a CPU, ASIC, FPGA, microprocessor, etc.), one or more communication components 254, memory 256, (multiple) antennas 260, power harvesting circuitry 259, and one or more communication buses 258 for interconnecting these components (sometimes referred to as a chipset). In some embodiments, the receiver device 104 includes one or more sensors 262, such as those described above with reference to FIG. Figure 2A One or more sensors 212 described. In some embodiments, the receiver device 104 includes an energy storage device 261 for storing energy harvested via the power harvesting circuit system 259. In various embodiments, the energy storage device 261 includes one or more batteries, one or more capacitors, one or more inductors, etc.

[0103] In some embodiments, the power harvesting circuit system 259 includes one or more rectifier circuits and / or one or more power converters. In some embodiments, the power harvesting circuit system 259 includes one or more components (e.g., power converters) configured to convert energy from power waves and / or energy bags into electrical energy (e.g., electricity). In some embodiments, the power harvesting circuit system 259 is further configured to provide power to a coupled electronic device (such as a laptop or phone). In some embodiments, providing power to the coupled electronic device includes converting the electrical energy from an AC form to a DC form (e.g., usable by the electronic device).

[0104] In some embodiments, antenna(s) 260 include one or more of the meander line antennas described in further detail below.

[0105] In some embodiments, the receiver device 104 includes one or more output devices, such as one or more indicator lights, a sound card, a speaker, a small display for displaying text messages and error codes, etc. In some embodiments, the receiver device 104 includes a location detection device for determining the location of the receiver device 103, such as a GPS (global positioning satellite) or other geo-location receiver.

[0106] In various embodiments, the one or more sensors 262 include one or more thermal radiation sensors, ambient temperature sensors, humidity sensors, IR sensors, occupancy sensors (e.g., RFID sensors), ambient light sensors, motion detectors, accelerometers, and / or gyroscopes.

[0107] The communication component(s) 254 enable communication between the receiver 104 and one or more communication networks. In some embodiments, the communication component(s) 254 are capable of communicating data using any of a variety of custom or standard wireless protocols (e.g., IEEE 802.15.4, Wi-Fi, ZigBee, 6LoWPAN, Thread, Z-Wave, Bluetooth Smart, ISA100.11a, WirelessHART, MiWi, etc.), custom or standard wired protocols (e.g., Ethernet, HomePlug, etc.), and / or any other suitable communication protocols, including those not yet developed as of the filing date of this document.

[0108] The communication component(s) 254 include, for example, hardware capable of communicating data using any of a variety of custom or standard wireless protocols (e.g., IEEE802.15.4, Wi-Fi, ZigBee, 6LoWPAN, Thread, Z-Wave, Bluetooth Smart, ISA100.11a, WirelessHART, MiWi, etc.), and / or any of a variety of custom or standard wired protocols (e.g., Ethernet, HomePlug, etc.), or any other suitable communication protocol, including communication protocols that have not yet been developed as of the date of filing of this document.

[0109] Memory 256 includes high-speed random access memory, such as DRAM, SRAM, DDR SRAM, or other random access solid-state memory devices; and optionally, includes non-volatile memory, such as one or more magnetic disk storage devices, one or more optical disk storage devices, one or more flash memory devices, or one or more other non-volatile solid-state storage devices. Memory 256, or alternatively non-volatile memory within memory 256, includes non-transitory computer-readable storage media. In some embodiments, memory 256 or non-transitory computer-readable storage media of memory 256 stores the following programs, modules, and data structures, or subsets or supersets thereof:

[0110] Operational logic 266, including processes for handling various basic system services and for performing hardware-related tasks; Communication module 268, for coupling to and / or communicating with remote devices (e.g., remote sensors, transmitters, receivers, servers, mapped storage, etc.) in conjunction with communication component(s) 254;

[0111] A sensor module 270 for obtaining and processing sensor data (e.g., in conjunction with sensor(s) 262) to, for example, determine the presence, velocity, and / or location of the receiver 103, the RF charging pad 100, or an object near the receiver 103;

[0112] a wireless power receiving module 272 for receiving (e.g., in conjunction with antenna(s) 260 and / or power harvesting circuitry 259) energy from power waves and / or energy bags; optionally, converting (e.g., in conjunction with power harvesting circuitry 259) energy (e.g., to direct current); transmitting energy to a coupled electronic device; and optionally storing energy (e.g., in conjunction with energy storage device 261); and

[0113] Database 274, including but not limited to:

[0114] o sensor information 276 for storing and managing data received, detected, and / or transmitted by one or more sensors (e.g., sensor 262 and / or one or more remote sensors);

[0115] o Device settings 278 for storing the receiver 103, coupled electronic devices, and / or one or more remote

[0116] the operational settings of the equipment; and

[0117] o Communication protocol information 280 for storing and managing protocols for one or more protocols (e.g., custom or standard wireless protocols, such as ZigBee, Z-Wave, etc., and / or custom or standard wired protocols, such as Ethernet)

[0118] information; and

[0119] A secure element module 282 for providing identification information to the RF charging pad 100 (eg, the RF charging pad 100 uses the identification information to determine whether the wireless power receiver 104 is authorized to receive wirelessly transferred power).

[0120] Each of the above identified elements (e.g., modules stored in the memory 256 of the receiver 104) is optionally stored in one or more of the aforementioned memory devices and corresponds to an instruction set for performing the above (multiple) functions. The modules or programs (e.g., instruction sets) identified above do not need to be implemented as independent software programs, processes, or modules, and therefore various subsets of these modules are optionally combined or otherwise rearranged in various embodiments. In some embodiments, the memory 256 optionally stores a subset of the above identified modules and data structures. In addition, the memory 256 optionally stores additional modules and data structures not described above, such as an identification module for identifying the device type of the connected device (e.g., the device type of the electronic device coupled to the receiver 104).

[0121] Now go to FIG. 3A to FIG. 8, show an embodiment of an RF charging pad 100 that includes components (e.g., load picks) for modifying the impedance value at each antenna of the RF charging pad 100, and a description of an antenna including a conductive line forming a meander line pattern is also provided with reference to these figures.

[0122] like Figure 3A As shown in , some embodiments include a radio frequency charging pad 100 that includes a load pick-off 106 for allowing modification of impedance values ​​at each antenna of the radio frequency charging pad 100. In some embodiments, the radio frequency charging pad 100 includes one or more antenna elements, each of which is powered / fed at a first end by a corresponding power amplifier switch circuit 103 and powered / fed at a second end by a corresponding adaptive load terminal 102 (hereinafter referred to as FIG. 3B to FIG. 3C Provides additional details and description of one or more antenna elements).

[0123] In some embodiments, the RF charging pad 100 also includes (or is in communication with) a central processing unit 110 (also referred to herein as a processor 110). In some embodiments, the processor 110 is a component of a single integrated circuit responsible for managing the operation of the RF charging pad 100, such as a processor 110. Figure 1B 1 and is included and is a component of the CPU 202 illustrated in FIG. 1 and is included and is a component of the RF power transmitter integrated circuit 160. In some embodiments, the processor 110 is configured to control the RF signal frequency and control the impedance value at each adaptive load terminal 102 (e.g., by communicating with a load pickoff or adaptive load 106, which may be an application specific integrated circuit (ASIC) or a variable resistor for generating various impedance values). In some embodiments, the load pickoff 106 is an electromechanical switch that is placed in an open circuit state or a short circuit state.

[0124] In some embodiments, an electronic device (e.g., a device that includes receiver 104 as an internal or externally connected component, such as a remote device placed on top of charging pad 100, which may be integrated into the housing of a streaming device or projector) uses energy transmitted from one or more RF antenna elements of charging pad 100 to receiver 104 to charge a battery and / or directly power the electronic device.

[0125] In some embodiments, the RF charging pad 100 is configured with a Figure 3AThe RF charging pad 100 includes more than one input terminal for receiving power from a power amplifier (PA) 108 in the RF charging pad, and more than one output terminal or adaptive load terminal 102. In some embodiments, the adaptive load terminal 102 at a specific area of ​​the RF charging pad 100 (e.g., an area including antenna elements located below where an electronic device to be charged (with an internal or externally connected RF receiver 104) is placed on the charging pad) is optimized to maximize the power received by the receiver 104. For example, the CPU 110, upon receiving an indication that an electronic device with an internal or externally connected RF receiver 104 has been placed on the pad 100 in a specific area 105 (the area 105 includes a group of antenna elements), can adjust the group of antenna elements to maximize the power delivered to the RF receiver 104. Adjusting the group of antenna elements can include: the CPU 110 instructing the load picker 106 to try various impedance values ​​for the adaptive load terminal 102 associated with the group of antenna elements. For example, the impedance value of a particular conductive line at an antenna element is given by a complex value Z=A+jB (where A is the real part of the impedance value and B is the imaginary part, such as 0+j0, 1000+j0, 0+50j, or 25+j75, etc.), and the load picker adjusts the impedance value to maximize the amount of energy transferred from the group of antenna elements to the RF receiver 104. In some embodiments, adjusting the group of antenna elements also includes or alternatively includes: the CPU 110 causes the group of antenna elements to transmit RF signals at various frequencies until a frequency is found at which the maximum amount of energy is transferred to the RF receiver 104. In some embodiments, adjusting the impedance value and / or the frequency at which the group of antenna elements transmits causes a change in the amount of energy transferred to the RF receiver 104. In this way, a maximized amount of energy delivered to the RF receiver 104 (e.g., to deliver at least 75% of the energy transmitted by the antenna elements of the pad 100 to the receiver 104, and in some embodiments, adjusting the impedance value and / or frequency may allow the receiver 104 to receive up to 98% of the transmitted energy) may be received at any particular point on the pad 100 where the RF receiver 104 may be placed.

[0126] In some embodiments, the input circuitry including power amplifier 108 may additionally include a device that can change the frequency of the input signal or a device that can operate at multiple frequencies simultaneously, such as an oscillator or a frequency modulator.

[0127] In some embodiments, the CPU 110 determines that the maximum amount of energy is being delivered to the RF receiver 104 when the amount of energy delivered to the RF receiver 104 exceeds a predetermined threshold (e.g., 75% or more of the transmitted energy is received, such as up to 98%), or by testing transmissions having multiple impedance values ​​and / or frequency values ​​and then by selecting the impedance and frequency combination that results in the maximum energy being delivered to the RF receiver 104 (as described with reference to the adaptive scheme below).

[0128] In some embodiments, an adaptive scheme is employed to adaptively adjust the impedance value and / or the frequency of the RF signal(s) transmitted from the RF antenna(s) 120 of the charging pad 100 in order to determine which combinations of frequency and impedance result in maximum energy transfer to the RF receiver 104. For example, a processor 110 coupled to the charging pad 100 may determine which combinations of frequency and impedance result in maximum energy transfer to the RF receiver 104 at a given location of the RF charging pad 100 (e.g., an area or region of the RF charging pad 100 that includes one or more RF antenna elements for transmitting RF signals, such as Figure 3A Different frequencies (i.e., within the allowed range of one or more operating frequencies) are tried in the area 105) in an attempt to adaptively optimize for better performance. For example, a simple optimization causes each load terminal to be open / disconnected or closed / shorted to ground (in an embodiment where relays are used to switch between these states), and the RF antennas in the area may also be caused to transmit at various frequencies. In some embodiments, for each combination of relay state (open or short) and frequency, the energy transmitted to the receiver 104 is monitored and compared to the energy transmitted when other combinations are used. The combination that maximizes the energy transmitted to the receiver 104 is selected and used to continue transmitting one or more RF signals to the receiver 104. In some embodiments, the above adaptive scheme is used as a reference for the following FIG. 9A to FIG. 9B , Fig.10 and FIG. 11A to FIG. 11E A portion of the described method is performed to help maximize the amount of energy transferred by the RF charging pad 100 to the receiver 104 .

[0129] As another example, if the pad 100 transmits RF waves using five frequencies in the ISM band, and the load pickoff 106 is an electromechanical relay for switching between an open circuit state and a short circuit state, employing an adaptive scheme would involve trying 10 combinations of frequency and impedance values ​​for each antenna element 120 or for a region of antenna elements 120 and selecting the combination that results in the best performance (i.e., the combination that results in the maximum power received at the receiver 104 or the maximum power transmitted from the pad 100 to the RF receiver 104).

[0130] The Industrial, Scientific and Medical radio band (ISM band) refers to a group of radio frequency bands or portions of the radio spectrum that are internationally reserved for radio frequency (RF) energy intended for scientific, medical and industrial requirements rather than for communications. In some embodiments, all ISM bands (e.g., 40 MHz, 900 MHz, 2.4 GHz, 5.8 GHz, 24 GHz, 60 GHz, 122 GHz, and 245 GHz) may be employed as part of an adaptive scheme. As a specific example, if the charging pad 100 operates in the 5.8 GHz band, employing an adaptive scheme would include transmitting a radio frequency signal and then adjusting the frequency in predetermined increments (e.g., 50 MHz increments resulting in a frequency of 5.75 GHz, 5.755 GHz, 5.76 GHz, etc.). In some embodiments, the predetermined increments may be 5 MHz, 10 MHz, 15 MHz, 20 MHz, 50 MHz increments, or any other suitable increments.

[0131] In some embodiments, the antenna element 120 of the pad 100 can be configured to operate in two different frequency bands, for example, a first frequency band having a center frequency of 915 MHz and a second frequency band having a center frequency of 5.8 GHz. In these embodiments, employing an adaptive scheme can include transmitting a radio frequency signal and then adjusting the frequency by a first predetermined increment until a first threshold of the first frequency band is reached, and then adjusting the frequency by a second predetermined increment (which may or may not be the same as the first predetermined increment) until a second threshold of the second frequency band is reached. For example, the antenna element 120 can be configured to transmit at 902 MHz, 915 MHz, 928 MHz (within the first frequency band) and then at 5.795 GHz, 5.8 GHz, and 5.805 GHz (within the second frequency band). Reference is made below to FIG. 14A to FIG. 14D and Fig.15 Additional details are provided regarding antenna elements capable of operating at multiple frequencies.

[0132] Now turn to FIG. 3B to FIG. 3C , illustrates a high-level block diagram showing a portion of a radio frequency charging pad in accordance with some embodiments.

[0133] Figure 3B A single transmitter antenna 120 is shown (which may be part of an antenna region including one such antenna 120 or an antenna array, which together form Figure 3A 100 ). In some embodiments, transmitter antenna 120 is also referred to as transmitter antenna element 120 . In some cases, a radio frequency receiving unit / antenna (RX) (or a device including receiving unit 104 as an internal or external connection component) is placed on top of a portion of pad 100 that includes transmitter antenna 120 (which includes conductive wires forming a meander line arrangement, such as Figure 3Bshown).

[0134] In some embodiments, the receiver 104 is not in direct contact with the metallic conductive lines of a single transmitter antenna 120 and is coupled only to the transmitter antenna 120 (ie, in a near-field region).

[0135] In some embodiments, the transmitter antenna 120 has a Figure 3B is marked as 121 (which can be Figure 3A of the terminals 102) and 123 (which can be connected to Figure 3A In some embodiments, the adaptive load is typically formed as a complex impedance, which may have a real part and an imaginary part (i.e., a complex adaptive load may be formed using active devices (e.g., an integrated circuit or chip made of transistors) or passive devices (formed by inductors / capacitors and resistors)). In some embodiments, the complex impedance is given by the formula Z=A+jB (e.g., 0+j0, 100+j0, 0+50j, etc.), as discussed above.

[0136] In some embodiments, the receiver 104 may also be considered a third terminal. To eliminate energy waste, the receiver 104 should be configured to absorb a maximum amount (e.g., 75% or more, such as 98%) of the inductive power traveling from the terminal 123 and toward the terminal 121. In some embodiments, the processor 110 is connected to the receiver 104 via a feedback loop (e.g., by exchanging messages using a short-range communication protocol, such as by exchanging messages via Bluetooth Low Energy (BLE)). In some alternative embodiments, the feedback loop from the receiver back to the CPU at the transmitter may use the same frequency band as the power transfer signal transmitted by the pad 100, rather than using a separate communication protocol and / or a different frequency band.

[0137] In some embodiments, the feedback loop and the messages exchanged may be used to indicate the amount of energy received, or may alternatively or additionally indicate an increase or decrease in the amount of energy received compared to a previous measurement. In some embodiments, the processor 110 monitors the amount of energy received by the receiver 104 at certain points in time, and controls / optimizes the adaptive load to maximize the power transmitted from the terminal 123 to the terminal 121. In some embodiments, monitoring the amount of energy transmitted includes one or both of the following: (i) receiving information from the receiver 104 (or a component of the electronic device in which the receiver 104 is located) indicating the amount of energy received by the receiver 104 at a certain point in time, and (ii) monitoring the amount of energy remaining in the conductive line at the terminal 121 (rather than having been absorbed by the receiver 104). In some embodiments, both monitoring techniques are used, while in other embodiments, one or the other of these monitoring techniques is used.

[0138] In some embodiments, receiver 104 (i.e., an electronic device that includes receiver 104 as an internal or external connection component) can be placed anywhere on top of charging pad 100 (i.e., partially or completely covering the conductive lines that form the meander pattern on the corresponding antenna element 120), and processor 110 will continue to monitor the amount of energy transmitted and make the necessary adjustments (e.g., to impedance and / or frequency) to maximize the energy transmitted to receiver 104.

[0139] To help explain the operation of the charging pad 100 and the antenna element 120 included therein, Figure 3B The transmitting antenna element 120 shown in FIG. 1 is divided into two parts: 1) part 125 starts from the terminal 123 of the antenna element 120 and extends to the edge of the receiver 104; and 2) part 127 is formed by the remaining part of the transmitting antenna element 120 and the terminal 121. Figure 3C The blocks are described in more detail. It should be understood that portions 125 and 127 are functional representations for purposes of illustration, and they are not intended to dictate a particular implementation of dividing the antenna element into separate portions.

[0140] Now turn to Figure 3C , a block diagram of transmitter antenna 120 is shown. In some embodiments, the effective impedance value (Z) starting from the point dividing portions 125 and 127 and ending at the connection of transmitter antenna 120 with adaptive load 106 (e.g., terminal 121) is 有效 ) will vary based on the location of receiver 104 on transmitter antenna 120 and based on the selected load provided by adaptive load 106 at terminal 121. In some embodiments, the selected load is provided by adaptive load 106 (in combination with Figure 3A The processor 110) is optimized to tune Z 有效, in such a way that the energy transferred between terminal 123 and receiver 104 is maximized (for example, 75% or more, such as 98%, of the energy emitted by the antenna element of pad 100 is received by RF receiver 104), while the energy transfer from terminal 123 to terminal 121 can also be kept to a minimum (for example, less than 25%, including as little as 2%, of the energy emitted by the antenna element of pad 100 that is not received by RF receiver 104 and ultimately reaches terminal 121 or is ultimately reflected back).

[0141] In an embodiment using an electromechanical switch (e.g., a mechanical relay) to switch between an open state and a short state, for a particular antenna element 120, moving the switch from the open state to the short state (e.g., shorted to a ground plane) results in an impedance value Z at the corresponding terminal 121 of the particular antenna element 120 being 0. 有效 In some embodiments, the impedance value of the above reference Figure 3A The frequency adaptation scheme discussed is used to test various combinations of impedance values ​​and RF signal frequencies in order to maximize the transmission to the RF receiver (e.g. FIG. 3A to FIG. 3C Receiver 104). In some embodiments, an integrated circuit (IC or chip) may be used instead of an electromechanical switch as the adaptive load 106. In such an embodiment, the adaptive load 106 is configured to adjust the impedance value along a range of values ​​(such as between 0 and infinity). In some embodiments, the IC may be formed of adaptive / reconfigurable RF active and / or passive elements (e.g., transistors and transmission lines) that are controlled by the firmware of the IC (and / or firmware executed on the CPU 110 that controls the operation of the IC). In some embodiments, the IC is generated and controlled by the firmware and based on information from the feedback loop (referenced above). Figure 3A The impedance of the RF power transmitter integrated circuit 160 (discussed above) can be changed to cover any load value selected from the Smith chart (or the IC can be designed to produce certain loads covering the values ​​that form part of the Smith chart). In some embodiments, this IC is different from the RF power transmitter integrated circuit 160 (discussed above) that is used to manage the overall operation of the pad 100. Figure 1B), and this other IC also communicates with the RF power transmitter integrated circuit 160 to allow the circuit 160 to control the adjustment of the impedance value. The Smith chart can be sampled and stored in a memory accessible by the processor 110 (e.g., as a lookup table), and the processor 110 can use the stored Smith chart to perform a lookup to determine the impedance values ​​to be tested. For example, the integrated circuit can be configured to select a predetermined number of complex values ​​of impedance values ​​(e.g., 5j to 10j, 100+0j, or 0+50j, etc.) to test in conjunction with various RF transmission frequencies in order to locate a combination of values ​​that optimizes the energy transferred to the receiver 104 (examples of maximizing energy transfer are discussed above).

[0142] In some other embodiments, having Figure 1B A transmitter or charging pad having more than one antenna element 120 with one adaptive load 106 can be configured to operate simultaneously in two or more different frequency bands, respectively. For example, the first antenna element operates at a first frequency or frequency band, the second antenna element operates at a second frequency or frequency band, the third antenna element operates at a third frequency or frequency band, and the fourth antenna element operates at a fourth frequency or frequency band, and the four frequency bands are different from each other. Therefore, a transmitter having two or more antenna elements 120 can be used as a multi-band transmitter.

[0143] Figure 3D is a block diagram of a simplified circuit illustrating energy flow within a portion of an antenna element that is transmitting a radio frequency signal, according to some embodiments. Figure 3D The reference numerals in Part 1 and Part 2 refer to Figure 3B and Figure 3C Of the parts illustrated in the figure, in particular, part 1 corresponds to part 125, and part 2 corresponds to part 127.

[0144] like Figure 3D As shown, the effective impedance (Z 有效 ) consists of a portion of the conductive line after the receiver 104 (which, in some embodiments, forms a meander pattern as discussed in more detail below) and an adaptive load (at Figure 3B and Figure 3C In some embodiments, the tuning load Z is optimized. 有效 , so that the energy transmitted from the PA to the receiver 104 is maximized; and the energy remaining in the conductive line is minimized when it reaches the adaptive load (as discussed above).

[0145] Figure 4 is a schematic diagram of an antenna element with two terminals according to some embodiments. Figure 4As shown, the input terminal or first terminal of the antenna element 120 (reference FIG. 3B to FIG. 3D Also described as terminal 123) is connected to the power amplifier 108, and the output terminal or second terminal (referenced above) FIG. 3B to FIG. 3D The antenna element 120 is also depicted as terminal 121) connected to a load pickoff 106 that allows for configuration of an adaptive load. In other words, in some embodiments, the antenna element 120 is fed by the power amplifier 108 from the first terminal, and the antenna element 120 is also terminated at the second terminal, at an adaptive load (e.g., a mechanical relay that switches between a short circuit state and an open circuit state).

[0146] In some embodiments, the charging pad 100 ( Figure 3A ) is made of a single or multiple layer copper antenna element 120 having conductive lines forming a meander line pattern. In some embodiments, each of these layers has a solid ground plane as one of its layers (eg, the bottom layer). Figure 4 The transmit antenna element shown in FIG. 5 shows and labels an example of a solid ground plane.

[0147] In some embodiments, the RF charging pad 100 (and the various antenna elements 120 included therein) is embedded in a consumer electronic device, such as a projector, a laptop computer, or a digital media player (such as a networked streaming media player connected to a television set to view streaming television programs and other content, such as a ROKU device). For example, by embedding the RF charging pad 100 in a consumer electronic device, a user can simply connect a peripheral device (such as a remote device of a projector or streaming media player (e.g., a remote device of a projector or streaming media player includes a corresponding receiver 104, such as 7A to 7D The example structure of the receiver 104 shown in the figure is placed on top of a projector or streaming media player, and the charging pad 100 included therein will be able to transmit energy to the receiver 104 connected internally or externally to a remote device, and then the receiver 104 will collect the energy to charge the remote device.

[0148] In some embodiments, the RF charging pad 100 can be included as a stand-alone charging device in a USB dongle on which the device to be charged is placed. In some embodiments, the antenna element 120 can be placed near the top surface, side surface, and / or bottom surface of the USB dongle so that the device to be charged can be placed in various positions in contact with the USB dongle (e.g., a head mounted device being charged may be located on top of, below, or suspended above the USB dongle and will still be able to receive RF transmissions from the embedded RF charging pad 100).

[0149] In some embodiments, the RF charging pad 100 is integrated into furniture such as tables, chairs, countertops, etc., allowing users to easily charge their devices (e.g., devices including corresponding receivers 104 as internal or external connection components) by simply placing the devices on top of the surface including the integrated RF charging pad 100.

[0150] Now go to Figure 5 , a flow chart of a method 500 for charging an electronic device via radio frequency (RF) power transfer is provided. Initially, a transmitter is provided 502, the transmitter comprising at least one RF antenna (e.g., FIG. 3B to FIG. 3D and Figure 4 In some embodiments, an array of RF antenna elements 120 are arranged adjacent to each other in a single plane, in a stack, or in a combination thereof, thereby forming the RF charging pad 100. In some embodiments, the RF antenna elements 120 each include an antenna input terminal (e.g., as described above with reference to FIG. 1 ). Figure 4 The first terminal 123 discussed above) and the antenna output terminal (eg, Figure 4 The second terminal 121 discussed).

[0151] In some embodiments, a receiver (e.g., FIG. 3A to FIG. 3D 104). The receiver also includes one or more RF antennas for receiving RF signals 310. In some embodiments, the receiver includes at least one rectenna that converts 318 the one or more RF signals into usable power to charge a device that includes the receiver 104 as an internal or external connection component. In use, the receiver 104 is placed 506 within a near-field RF distance from at least one antenna. For example, the receiver can be placed on top of at least one RF antenna or on top of a surface adjacent to at least one RF antenna, such as a surface of the charging pad 100.

[0152] One or more RF signals are then transmitted 508 via at least one RF antenna. The system is then monitored 512 / 514 to determine the amount of energy transmitted from the at least one antenna to the RF receiver via the one or more RF signals (also as discussed above). In some embodiments, this monitoring 512 occurs at the transmitter, while in other embodiments, monitoring 514 occurs at the receiver, which sends data back to the transmitter via a return channel (e.g., via a wireless data connection using WIFI or Bluetooth). In some embodiments, the transmitter and receiver exchange messages via the return channel, and these messages may indicate the energy transmitted and / or received in order to inform the adjustments made at step 516.

[0153] In some embodiments, a characteristic of the transmitter is adaptively adjusted at step 516 in an attempt to optimize the amount of energy delivered from the at least one RF antenna to the receiver. In some embodiments, this characteristic is the frequency of the one or more RF signals and / or the impedance of the transmitter. In some embodiments, the impedance of the transmitter is the impedance of an adjustable load. Also in some embodiments, at least one processor is further configured to control the impedance of the adaptive load. Additional details and examples regarding impedance and frequency adjustment are provided above.

[0154] In some embodiments, the transmitter includes a power input configured to be electrically coupled to a power source, and at least one processor (e.g., FIG. 3A to FIG. 3B In some embodiments, the at least one processor is further configured to control a frequency of at least one signal sent to the antenna.

[0155] In some embodiments, the transmitter further includes a power amplifier (eg, Figure 3A , Figure 3B , Figure 3D and Figure 4 Some embodiments further include a PA 108 electrically coupled to an antenna output terminal (eg, FIG. 3A to FIG. 3C and Figure 4 In some embodiments, the at least one processor dynamically adjusts the impedance of the adaptive load based on the monitored amount of energy transmitted from the at least one antenna to the RF receiver. In some embodiments, the at least one processor simultaneously controls the frequency of at least one signal sent to the antenna.

[0156] In some embodiments, each radio frequency antenna of the transmitter includes: a conductive wire forming a meander line pattern; a first terminal (e.g., terminal 123) at a first end of the conductive wire, the first terminal being used to receive a current flowing through the conductive wire at a frequency controlled by one or more processors; and a second terminal (e.g., terminal 121) at a second end of the conductive wire that is different from the first terminal, the second terminal being coupled to a component (e.g., adaptive load 106) controlled by one or more processors and allowing the impedance value of the conductive wire to be modified. In some embodiments, the conductive wire is arranged on or within a first antenna layer of a multilayer substrate. Also in some embodiments, the second antenna is arranged on or within a second antenna layer of a multilayer substrate. Finally, some embodiments also provide a ground plane arranged on or within a ground plane layer of a multilayer substrate.

[0157] In some embodiments, the above reference Figure 5 The method described is combined with the following references FIG. 9A to FIG. 9B, Fig.10 and FIG. 11A to FIG. 11E The method described herein is performed. For example, an operation of modifying / adjusting impedance values ​​is performed after determining which antenna areas ("determined antenna areas") are used to transmit wireless power to a receiver, and then adjusting the impedance values ​​at the determined antenna areas to ensure that a maximum amount of power is wirelessly transmitted to the receiver through the antennas within the determined antenna areas.

[0158] Figures 6A to 6E is a schematic diagram showing various configurations of a single antenna element within a radio frequency charging pad according to some embodiments. FIG. 6A to FIG. 6E As shown, the RF charging pad 100 ( Figure 3A ) may include antenna elements 120 made using different structures.

[0159] For example, FIG. 6A to FIG. 6B 1 shows an example of a structure of an antenna element 120 including multiple layers, each layer including conductive wires formed into a meander line pattern. The conductive wires at each corresponding layer may have the same ( Figure 6B ) or different ( Fig. 6A ) width (or length, or trace gauge, or pattern, spacing between each trace, etc.). In some embodiments, the meander line pattern can be designed to have variable length and / or width at different locations of the pad 100 (or a single antenna element 120), and the meander line pattern can be printed on more than one substrate of a single antenna element 120 or pad 100. These configurations of the meander line pattern allow for greater freedom, and therefore more complex antenna structures can be constructed, which allow for wider operating bandwidths and / or coupling ranges for individual antenna elements 120 and RF charging pads 100.

[0160] FIG. 6C to FIG. 6E Additional example structures are provided in: Figure 6C An example of a structure of an antenna element 120 is shown that includes multiple layers of conductive lines forming a meander line pattern that also has sliding coverage (in some embodiments, the respective meander line patterns may be placed in different substrates, wherein only a portion of a first meander line pattern of a respective substrate overlaps with a second meander line pattern of a different substrate (i.e., sliding coverage), and such a configuration facilitates extending coverage across the width of the antenna structure); Fig.6D An example of a structure of an antenna element 120 is shown, the antenna element including a conductive line having different lengths at each turn within a meander line pattern (in some embodiments, using different lengths at each turn helps to extend the coupling range of the antenna element 120 and / or helps to increase the operating bandwidth of the RF charging pad 100); and Fig. 6EExamples of structures of antenna element 120 are shown that include conductive lines forming two adjacent meander line patterns (in some embodiments, having conductive lines forming two adjacent meander line patterns and helping to extend the width of antenna element 120). All of these examples are non-limiting, and any number of combinations and multi-layer structures may be implemented using the example structures described above.

[0161] 7A to 7D is a schematic diagram of an antenna element for a radio frequency receiver according to some embodiments. In particular, 7A to 7D A radio frequency receiver (eg, FIG. 3A to FIG. 3D and Figure 4 Examples of structures of receivers 104 include: (i) a receiver having conductive lines forming a meander line pattern (the conductive lines may or may not be supported by a fixed ground plane or reflector), such as Fig. 7A (unipolar receiver) and Figure 7B (bipolar receiver) shown). FIG. 7C to FIG. 7D Additional examples of radio frequency receiver structures are shown having dual polarity and conductive lines forming a meander line pattern. 7A to 7D Each structure shown in can be used to provide a different coupling range, coupling direction and / or bandwidth for a corresponding RF receiver. As a non-limiting example, when using in a receiver Fig. 7A When the antenna element shown in , a very small receiver can be designed / built that couples to the pad 100 in only one direction. As another non-limiting example, when FIG. 7B to FIG. 7D When the antenna element shown in is used in a receiver, the receiver can couple to the pad 100 in any direction.

[0162] Co-owned U.S. Patent Application No. 15 / 269,729 also provides additional examples and descriptions of meander line patterns for antenna elements (e.g., in Figure 2A To Figure 2D, Figure 3, Figure 4 , Figure 5 Figure 7 Figure 8 as well as FIG. 9A to FIG. 9B and those shown in and described in the specification) and descriptions of the functionality of a power transmission system including an antenna element having a meander line pattern (e.g., paragraphs

[0022] to

[0034] and Figure 1A to Figure 1B ), and the disclosure of this commonly owned application therefore supplements the description of antenna elements with meander line patterns provided herein (for both receivers and transmitters, or a combination thereof).

[0163] Figure 8is a schematic diagram of an RF charging pad with multiple transmitting antenna elements (unit cells) forming a larger RF charging / transmitting pad according to some embodiments. In some embodiments, the RF charging pad 100 is formed as an array of adjacent antenna elements 120 (the distance between the units can be optimized for best coverage). In some embodiments, when a receiver is placed in the area / gap between adjacent antenna elements 120, an attempt is made to optimize energy transfer (e.g., according to the above reference Figure 3A In some cases, the adaptive scheme discussed above may not result in an increase in energy transfer above an acceptable threshold level (e.g., 75% or more). Thus, in these cases, adjacent antenna elements can be configured to transmit RF waves at full power while transferring additional energy to a receiver placed on the surface of the RF charging pad and at a location between adjacent antenna elements 120.

[0164] As a possible configuration according to some embodiments, port (or terminal) group 1 ( Figure 8 ) supplies power, and port (or terminal) groups 2 and 3 provide adaptive loads (e.g., electromechanical relays that move between a short circuit state and an open circuit state). As another example of a suitable configuration, port (or terminal) groups 1, 2, and 3 can also be used to power charging pad 100 via a power amplifier (simultaneously or switching one group at a time when needed).

[0165] In some embodiments, each transmitting antenna element 120 of the RF charging pad 100 forms a separate antenna zone that is controlled by a feed (PA) terminal and one or more terminals to support (multiple) adaptive loads, as explained in detail above. In some embodiments, feedback from the receiver helps determine the antenna zone on top of which the receiver is placed, and this determination activates the zone. In the event that the receiver is placed between two or more zones (e.g., in the zone / gap between adjacent antenna elements 120), additional adjacent zones can be activated to ensure that sufficient energy is transferred to the receiver. The following reference FIG. 9A to FIG. 9B , Fig.10 and FIG. 11A to FIG. 11E Additional details are provided regarding determining an area for transmitting wireless power to a receiver.

[0166] FIG. 9A to FIG. 9B is a flow chart illustrating a method 900 of selectively activating one or more antenna regions (eg, activating antennas associated therewith) in a near field charging pad according to some embodiments. The operations of method 900 are performed by a near field charging pad (eg, Figure 1B and Figure 2A RF charging pad 100) or one or more components thereof (e.g., the above reference Figure 1A to Figure 1B and Figure 2AIn some embodiments, method 900 corresponds to storing in a computer memory or computer readable storage medium (e.g., Figure 2A Instructions in the memory 206 of the RF charging pad 100).

[0167] The near field charging pad includes one or more processors (e.g., Figure 1B CPU 202), wireless communication components (e.g., Figure 1A and Figure 2A (multiple) communication components 204), and multiple antenna areas (e.g., Figure 1B Antenna regions 290-1 and 290-N), each of which includes at least one antenna element (e.g., Figure 2A One of the antennas 210, which may be a reference FIG. 3A to FIG. 6E In some embodiments, the near-field charging pad includes different antennas (or unit cells including antennas, also referred to herein as antenna elements), each antenna being included in a corresponding antenna region. For example, Figure 1B As shown, antenna region 290-1 includes antenna 210-A. In another example, also as Figure 1B As shown, antenna region 290-N includes multiple antennas. Antenna regions may also be referred to as antenna groups, such that the near-field charging pad includes multiple antenna regions or groups, and each corresponding region / group includes at least one different antenna element (e.g., at least one antenna 210). It should be noted that the antenna region may include any number of antennas, and the number of antennas associated with a particular antenna region may be modified or adjusted (e.g., the CPU subsystem 170 of the RF power transmitter integrated circuit 160 responsible for managing the operation of the near-field charging pad 100 dynamically defines each antenna region at different points in time, as discussed in more detail below). In some embodiments, each antenna region includes the same number of antennas.

[0168] In some embodiments, one or more processors are a single integrated circuit (e.g., Figure 1B The RF power transmitter integrated circuit 160 of the near-field charging pad is used to control the operation of the near-field charging pad. In some embodiments, one or more processors and / or wireless communication components of the near-field charging pad are external to the near-field charging pad, such as one or more processors of a device in which the near-field charging pad is embedded. In some embodiments, the wireless communication component is a radio transceiver (e.g., a Bluetooth radio, a WI-FI radio, etc. for exchanging communication signals with a wireless power receiver).

[0169] In some embodiments, the method includes establishing (904) one or more device detection thresholds during a calibration process of the near field charging pad. In some cases, the calibration process is performed after manufacturing the near field charging pad and includes placing various types of devices (e.g., smart phones, tablet computers, laptop computers, connected devices, etc.) on the near field charging pad and then measuring the minimum amount of reflected power detected at the antenna area when transmitting a test power transmission signal to the various types of devices. In some cases, the first device-specific threshold is established as a value corresponding to 5% or less of the minimum amount of reflected power. In some embodiments, a second device-specific threshold is also established so that if no antenna area can meet the first threshold (e.g., because the wireless power receiver is located at a boundary between antenna areas), a higher second threshold can be used to locate more than one antenna area for transmitting power to the wireless power receiver (as discussed in more detail below). In some embodiments, multiple first and second device-specific detection thresholds are established for each of the various types of devices, and the multiple first and second device-specific detection thresholds can be stored in a memory associated with the RF power transmitter integrated circuit 160 (e.g., Figure 2A in the memory 206).

[0170] The method 900 also includes detecting (906) via the wireless communication component that a wireless power receiver is within a threshold distance of the near-field charging pad. In some cases, the detection may occur after the near-field charging pad is turned on (e.g., powered on). In these cases, the near-field charging pad scans an area around the near-field charging pad (e.g., scans for wireless power receivers that are within a threshold distance, such as 1 to 1.5 meters, from the near-field charging pad 100) to determine if there are any wireless power receivers within the threshold distance of the near-field charging pad 100. The near-field charging pad may use the wireless communication component (e.g., Figure 2A (multiple) communication components 204, such as a Bluetooth radio) to communicate with the wireless power receiver associated with the wireless communication component (e.g., Figure 2B In some embodiments, after detecting a wireless power receiver within a threshold distance of the near-field charging pad, a device detection threshold is selected by one or more processors (from the multiple first and second device detection thresholds discussed above). For example, the wireless communication component of the wireless power receiver is used to provide information identifying the device type to the near-field charging pad, such as a Bluetooth or Bluetooth low energy advertisement signal that includes this information. In some embodiments, in order to save energy and extend the life of the near-field charging pad and its components, wireless power is not transmitted (and the device detection and antenna selection algorithms discussed herein are not initiated) until a wireless power receiver is detected within a threshold distance of the near-field charging pad.

[0171] In some embodiments, detecting 906 also includes performing an authorization handshake (e.g., using Figure 2A and 2B The method may also use the secure element modules 234 and 282 in the near field charging pad to ensure that the wireless power receiver is authorized to receive wirelessly transferred power from the near field charging pad, and if it is determined that the wireless power receiver is so authorized, the method only proceeds to operation 908. In this way, the near field charging pad ensures that only authorized wireless power receivers can receive wirelessly transferred power and ensures that no device can draw power transmitted by the near field charging pad.

[0172] The method 900 further includes: in response to detecting that the wireless power receiver is within a threshold distance of the near-field charging pad, determining (912) whether the wireless power receiver has been placed on the near-field charging pad. In some embodiments, this is achieved by transmitting (908) a test power transfer signal using each of the plurality of antenna regions and monitoring (910) an amount of reflected power at the near-field charging pad while transmitting the test power transfer signal.

[0173] In some embodiments, if the reflected power amount does not meet the device detection threshold (e.g., the reflected power amount is greater than 20% of the power transmitted with the test power transmission signal), it is determined that the wireless power receiver is not placed on the surface of the near-field charging pad (912-No). Based on this determination, at step 914, the near-field charging pad continues to transmit the test power transmission signal using each of the multiple antenna areas (i.e., proceeds to step 908). In some embodiments, the operations at 908 and 910 are performed until it is determined that the device detection threshold has been met.

[0174] In some embodiments, the amount of reflected power is measured at each of a plurality of antenna regions (e.g., each antenna region may be associated with a signal such as Figure 1B ), while in other embodiments, a single component of the RF power transmitter integrated circuit 160 (e.g., an ADC / DAC / power detector) may be used to measure the reflected power amount. When the reflected power amount satisfies the device detection threshold (912-Yes), it is determined that the wireless power receiver has been placed on the near-field charging pad. For example, when the reflected power amount is 20% or less of the power amount transmitted along with the test power transmission signal, the reflected power amount may satisfy the device detection threshold. Such a result indicates that the wireless power receiver absorbs / captures a sufficient amount of power transmitted along with the test power transmission signal.

[0175] In some embodiments, other types of sensors (e.g., Figure 2AA sensor 212, ) is included in the near field charging pad or communicates with the near field charging pad to help determine when the wireless power receiver has been placed on the near field charging pad. For example, in some embodiments, one or more optical sensors (e.g., when light is blocked by a portion of the pad, then this can provide an indication that the wireless power receiver has been placed on the pad), one or more vibration sensors (e.g., when vibrations are detected at the pad, then this can provide an indication that the wireless power receiver has been placed on the pad), one or more strain gauges (e.g., when the strain level at the surface of the pad increases, then this can provide an indication that the wireless power receiver has been placed on the surface), one or more thermal sensors (e.g., when the temperature at the surface of the pad increases, then this can provide an indication that the wireless power receiver has been placed on the surface), and / or one or more load cells (e.g., when the weight measured on the surface of the pad increases, then this can provide an indication that the wireless power receiver has been placed on the surface) are used to help make this determination.

[0176] In some embodiments, prior to transmitting the test power transfer signal, the method includes determining that the wireless power receiver is authorized to receive wirelessly transferred power from the near-field charging pad. FIG. 2A to FIG. 2B As shown, the wireless power receiver 104 and the near-field charging pad 100 may include security element modules 282 and 234, respectively, which are used to perform this authorization process, thereby ensuring that only authorized receivers can receive wirelessly transferred power from the near-field charging pad.

[0177] The method 900 further includes: selectively transmitting (916) a corresponding test power transfer signal having a first set of transmission characteristics through corresponding antenna elements included in the plurality of antenna regions based on determining that the wireless power receiver has been placed on the near-field charging pad. In some embodiments, selectively or sequentially transmitting (918) is performed using each antenna region in the plurality of antenna regions. Selectively or sequentially transmitting refers to the process of selectively activating the antenna regions one at a time to cause one or more antennas associated with the respective antenna regions to transmit the test power transfer signal.

[0178] Reference now Fig. 9B, the method 900 further includes determining (920) whether a specific power transfer parameter associated with the transmission of a corresponding test power transfer signal by at least one specific antenna area of ​​the plurality of antenna areas (during the sequential or selective transmission operation at 916 and / or 918) satisfies a power transfer criterion (e.g., whether the specific power transfer parameter indicates that more than a threshold amount of power is transmitted to the wireless power receiver by the at least one specific antenna area). In some embodiments, each corresponding power transfer parameter corresponds to an amount of power received by the wireless power receiver based on the transmission of the corresponding test power transfer signal by a corresponding antenna group of the plurality of antenna groups.

[0179] When the one or more processors determine that the specific power transfer parameters meet the power transfer criteria (920-yes), the method further includes transmitting (922) a plurality of additional power transfer signals to the wireless power receiver using the at least one specific antenna area, wherein each of the plurality of additional power transfer signals is transmitted with a second set of transmission characteristics that is different from the first set of transmission characteristics. In some embodiments, the second set of transmission characteristics is determined by adjusting at least one characteristic of the first set of transmission characteristics to increase the amount of power delivered to the wireless power receiver by the specific antenna group. In addition, in some embodiments, at least one of the adjusted characteristics is a frequency or an impedance value (and the frequency and impedance value can be adjusted using the adaptive scheme discussed above).

[0180] The test power transfer signals discussed above are used to help determine which antenna areas to use to transfer wireless power to the wireless power receiver. In some embodiments, the wireless power receiver does not use these test power transfer signals to provide power or charge the wireless power receiver or a device associated therewith. Instead, multiple additional power transfer signals are used to provide power or charge the wireless power receiver. In this way, the near-field charging pad is able to reserve resources during the device detection phase (e.g., when transmitting the test power transfer signal) until a suitable antenna area is located for transmitting the multiple additional power transfer signals. In this way, method 900 is able to use a test signal (i.e., a test power transfer signal having a first set of transmission characteristics) to locate the position of the wireless power receiver, and then transmit using an antenna from the antenna area that is best suited to provide a power transfer signal given the position of the wireless power receiver on the near-field charging pad. As described below with reference to Fig.10 Discussed in more detail, this process may include a coarse search of antenna regions (eg, the coarse search may include operations 908 through 918) and a fine search of antenna regions (eg, the fine search may include operations 920 through 934).

[0181] In some embodiments, a power control process is also used ( Fig.11E ) to help optimize the power level delivered to the wireless power receiver using the selected antenna area (e.g., power control may be performed after operations 922, 930, or 934 to tune the transmission of wireless power using the antenna area selected during method 900). As part of the power control process, the near-field charging pad may adjust at least one characteristic of the second set of transmission characteristics based on information received from the wireless power receiver when transmitting the additional plurality of power transfer signals, the information being used to determine the power level wirelessly delivered by the near-field charging pad to the wireless power receiver.

[0182] Returning to operation 920, in response to determining that none of the power transfer parameters associated with the transmission of the test power transfer signal during the (multiple) sequential or selective transmission operations at 916 (and optionally 918) meet the power transfer criteria (920-No), method 900 further includes selecting (924) two or more antenna regions (also interchangeably referred to herein as more than two antenna regions) based on the associated respective power transfer parameters of the antenna regions. This may occur when the wireless power receiver is not centered on any particular antenna region (e.g., the receiver may be on more than one antenna region). For example, at operation 924, two or more antenna regions that transmit the highest amount of power to the wireless power receiver during the sequential or selective transmission operations at 916 (and optionally 918) are selected based on the respective power transfer parameters of the antenna regions. In this manner, in some embodiments, a more refined search for the most efficient antenna region is initiated by selecting two or more antenna regions that most efficiently transmit power to the wireless power receiver during the operations at 916 / 918 (based on the antenna regions' respective associations with power transfer parameters, the power transfer parameters of the antenna regions being higher than the power transfer parameters of the other antenna regions). In these embodiments, the respective power transfer parameters may be monitored for each antenna region (in conjunction with operations 916 / 918), and then compared to determine which of the multiple antenna regions are selected as the two or more antenna regions for transmitting wireless power.

[0183] After selecting two or more antenna areas, the method further includes: (i) updating the test power transfer signal by modifying at least one characteristic (e.g., frequency, impedance, amplitude, phase, gain, etc.) of the test power transfer signal based on a previous transmission (e.g., based on feedback received from the wireless power receiver regarding the power level received by the wireless power receiver, or based on the amount of reflected power measured at each antenna group after the transmission), and (ii) transmitting (926) the updated test power transfer signal using each of the two or more antenna areas.

[0184] The method 900 further includes determining (928) whether a specific power transfer parameter associated with the transmission of the updated corresponding test power transfer signal through the area in the two or more antenna areas satisfies the power transfer standard. In response to determining that the specific power transfer parameter associated with the transmission of the updated corresponding test power transfer signal through the area in the two or more antenna areas satisfies the power transfer standard (928-yes), the method 900 further includes transmitting (930) a plurality of additional power transfer signals to the wireless power receiver using the area in the two or more antenna areas, wherein each of the plurality of additional power transfer signals is transmitted with a second set of transmission characteristics different from the first set of transmission characteristics. The plurality of additional power transfer signals are used to wirelessly transfer power to the wireless power receiver (or an electronic device coupled to the wireless power receiver).

[0185] In some embodiments, determining at operations 920 and 928 that a particular power transfer parameter satisfies a power transfer criterion may include determining that a corresponding power transfer parameter (associated with at least one particular region and / or a region of the two or more antenna regions) indicates that a first threshold power amount is transferred to the wireless power receiver. If such a determination is made at operation 928, this indicates that the region is the only antenna region of the two or more antenna regions having a corresponding power transfer parameter indicating that the first threshold power amount is transferred to the wireless power receiver through the region in conjunction with operation 926.

[0186] In some embodiments, the first threshold power amount corresponds to the amount of power received by the wireless power receiver (in some cases, the first threshold power amount may alternatively correspond to the amount of reflected power detected at the near-field charging pad). As discussed above, in some embodiments, the calibration process is performed after manufacturing the near-field charging pad and includes placing various types of devices (e.g., smartphones, tablet computers, laptops, connected devices, etc. coupled to each other with the wireless power receiver) on the near-field charging pad, and then measuring the maximum amount of power received at the receiver (or the device coupled thereto) after the antenna group transmits the test transmission signal to the various types of devices. In some cases, the first threshold is established as a value corresponding to a certain percentage of the maximum received power amount (e.g., the receiver receives approximately 85% or more of the power transmitted by a particular antenna area).

[0187] As explained above, during an embodiment of the calibration process, a second threshold is also established so that if no antenna area is able to meet the first threshold (e.g., because the wireless power receiver may be located at a boundary between antenna groups), the second threshold can be used to locate more than one antenna area for transmitting wireless power to the wireless power receiver (as discussed below). This second threshold can be another percentage (e.g., 65%) of the maximum amount of reflected power measured during the calibration process. In some embodiments, the first and second thresholds are determined as respective device-specific first and second thresholds for each device undergoing the calibration process.

[0188] In some embodiments, method 900 includes determining (928-No): (i) none of the two or more antenna regions is transmitting a first threshold power amount to the wireless power receiver, and (ii) an additional power transfer parameter associated with an additional antenna region of the two or more antenna regions satisfies a power transfer criterion. For example, the corresponding power transfer parameter indicates that a first power amount transmitted to the wireless power receiver by a region of the two or more antenna regions is above a second threshold power amount and below a first threshold power amount, and the additional power transfer parameter further indicates that a second power amount transmitted to the wireless power receiver by the additional antenna region is above the second threshold power amount and below the first threshold power amount. In other words, if none of the two or more antenna regions is capable of transmitting enough power to the wireless power receiver to meet the first threshold power amount, the method proceeds to determine whether the two antenna groups are transmitting enough power to the wireless power receiver to meet a lower second threshold power amount. For example, the wireless power receiver may be located at a boundary between two antenna groups, so that neither antenna group is capable of meeting the first threshold, but the two antenna groups may each individually meet the second threshold power amount.

[0189] When the power transfer parameters associated with the transmission of the updated test power transfer signal by the two or more antenna regions are determined by the one or more processors of the near field charging pad to meet the power transfer criteria (932-yes), the method further includes transmitting (934) multiple additional power transfer signals to the wireless power receiver using the two or more antenna regions. This may occur when the wireless power receiver is placed between two adjacent antenna regions. In some embodiments, the two or more antenna regions each simultaneously transmit the additional multiple power transfer signals to provide power to the wireless power receiver.

[0190] like Fig. 9BAs also shown in , if the two or more areas do not have power transfer parameters that meet the power transfer criteria (932-No), the method 900 returns to operation 906 to begin searching for a receiver (or searching for a different receiver again) because no antenna area that can efficiently transfer wireless power to the receiver has been located. In some embodiments, the method 900 may alternatively return to operation 924 to begin transmitting a test power transfer signal with different characteristics to then determine whether those characteristics can allow the two or more antenna areas to transfer enough wireless power to the receiver to meet the power transfer criteria. In some embodiments, the method 900 returns to operation 924 a predetermined number of times (e.g., 2 times), and if the two or more areas still do not have power transfer parameters that meet the power transfer criteria, the method then returns to operation 906 to begin searching for a new receiver.

[0191] In some embodiments, after method 900 successfully locates an antenna area for wirelessly transferring power to a receiver (e.g., at operations 922, 930, and 934), method 900 then returns to operation 906 to search for a new receiver. In some embodiments, the near field charging pad is capable of simultaneously transferring wireless power to multiple receivers at any particular point in time, and therefore, repeating method 900 again allows the near field charging pad to appropriately determine which antenna areas to use for transferring wireless power to each of these multiple receivers.

[0192] In some embodiments, information for determining the corresponding power transfer parameters for each antenna area of ​​the near-field charging pad is provided by the wireless power receiver to the near-field charging pad via the wireless communication component of the near-field charging pad (e.g., the receiver transmits information for determining the amount of power received by the receiver from the test power transfer signal discussed above). In some embodiments, this information is sent via a connection between the wireless communication component of the near-field charging pad and the wireless power receiver, and the connection is established upon determining that the wireless power receiver has been placed on the near-field charging pad.

[0193] Additionally, in some embodiments, the near field charging pad dynamically creates or defines the antenna area. Figure 1B, the near-field charging pad may define a first antenna region 290-1 as including a single antenna 210-A, and may define another antenna region 290-N as including more than one antenna 210. In some embodiments, the antenna regions may be redefined at various stages of the method 900 discussed above. For example, based on determining that the two or more antenna regions do not have power transfer parameters that meet the power transfer criteria (932-No), the near-field charging pad may redefined the antenna regions to include multiple antennas for each antenna region (rather than each antenna region including a single antenna). In this way, the method 900 is able to dynamically define the antenna regions to help ensure that the appropriate antenna regions are located that can be used to transmit wireless power to a receiver that has been placed on the near-field charging pad.

[0194] Fig.10 1 is an overview of a process 1000 for selectively activating one or more antenna groups in a near-field charging pad according to some embodiments. Some operations in process 1000 correspond to or supplement those in the above referenced FIG. 9A to FIG. 9B The operations described in method 900 are as follows. Fig.10 As shown, process 1000 begins by charging a near-field charging pad (e.g., Figure 1A to Figure 1B and Figure 2A The radio frequency charging pad 100 of the embodiment of the present invention detects (1002) a wireless power receiver (e.g., Figure 2B Wireless power receiver 104) (operation 1002 corresponds to Fig.9A Operations 906 to 912 in (Yes). Process 1000 further includes: performing a coarse search (1004), performing a fine search (1006), and performing a power control routine (1008). FIG. 11A to FIG. 11E Each step in process 1000 is described in further detail. It should be noted that in some embodiments, process 1000 begins with a near field charging pad detecting 1002 a wireless power receiver on and then within range of the near field charging pad.

[0195] Fig.11A 1 is a flow chart detailing a process 1002 for detecting a wireless power receiver within range of a near field charging pad and subsequently on the near field charging pad (or, in some embodiments, on the near field charging pad and subsequently within range of the near field charging pad). The process 1002 includes enabling the near field charging pad (1102), i.e., powering on the near field charging pad. Thereafter, the near field charging pad scans (1104) for wireless power receivers and detects (1106) a wireless power receiver within range based at least in part on a received signal strength indicator (RSSI). To obtain the RSSI, the near field charging pad may use a wireless communication component (e.g., Figure 2AThe communication component(s) 204, such as a Bluetooth radio) scans for signals (e.g., Bluetooth advertising signals) broadcast by a wireless communication component associated with a wireless power receiver. Detecting a wireless power receiver within range of a near-field charging pad is discussed in further detail above with reference to operation 906 of method 900.

[0196] Next, the near-field charging pad detects (1108) the wireless power receiver on the near-field charging pad. In some embodiments, the near-field charging pad uses the process discussed above with reference to operations 908 to 914 to establish that the wireless power receiver is on the near-field charging pad until it is determined that the wireless power receiver has been placed on the near-field charging pad. In some embodiments, operation (1108) occurs before operation (1102).

[0197] Continuing, the near field charging pad establishes (1110) a communication channel with the wireless power receiver in response to detecting the wireless power receiver on the near field charging pad.

[0198] Now go to Fig. 11B , the method proceeds to process 1004, in which the near field charging pad performs a rough search (1004). When performing the rough search 1004, the near field charging pad is detected by the antenna area (e.g., Figure 1B The method 900 may be implemented by powering (1122) an antenna region 290-1 of the antenna region. In some embodiments, powering the antenna region includes transmitting a test power transmission signal having a first set of transmission characteristics (e.g., phase, gain, direction, amplitude, polarity, and / or frequency) by antenna elements included in the antenna region. Transmitting the test power transmission signal is discussed in further detail above with reference to steps 916 to 918 of method 900.

[0199] Continuing with the coarse search 1004 , the near field charging pad records 1124 the amount of power received by the wireless power receiver (“reported power”). In some embodiments, the reported power is transmitted by the wireless power receiver to the near field charging pad via the communication channel established at operation 1110 .

[0200] The near-field charging pad repeats (1126) the above steps (1122) and (1124) for all antenna zones that have been defined for the near-field charging pad. Thereafter, in some embodiments, the near-field charging pad selects (1128) a group of antenna zones (e.g., 2 or 3 or some larger or smaller number of zones, as appropriate) based on the reported power and a configured threshold (e.g., power transfer criteria). For ease of discussion, each antenna zone in the group includes a single antenna 210 (e.g., Figure 1B However, it should be understood that the near field charging pad may also select a single antenna area including multiple antennas 210 instead of selecting a group of antenna areas. Figure 1B As shown, antenna region 290-N includes a plurality of antennas 210. In addition, each antenna region in the group may also include a plurality of antennas, depending on circumstances.

[0201] Now go to Fig. 11C , after selecting a set of antenna regions based on the reported power, the near field charging pad performs a fine search process (1006). In some embodiments, the fine search 1006 is used to determine which (which) antenna regions are best suited to wirelessly transfer power to the wireless power receiver based on the location of the wireless power receiver on the near field charging pad. When performing the fine search (1006), the near field charging pad selects (1132) at least one antenna region from the set of antenna regions selected using the coarse search, and for the at least one antenna region, the near field charging pad scans (1134) across available frequencies and / or impedances (i.e., tunes the transmission of the power transfer signal of the at least one antenna region). Thereafter, the near field charging pad records (1136) those characteristics that maximize the amount of received power reported by the wireless power receiver. In some embodiments, operations 1134 and 1136 (1138) are repeated for each antenna region in the set of antenna regions, and the near field charging pad selects (1140) the antenna region (Z1) that transfers the greatest amount of power to the wireless power receiver. In addition, the near-field charging pad also records the frequency (and other transmission characteristics) and relay location through antenna zone Z1 to achieve the maximum amount of power delivered to the wireless power receiver.

[0202] In some cases or situations, the amount of power delivered to the wireless power receiver via antenna zone Z1 does not meet the threshold power amount. In these cases or situations, the near field charging pad performs a neighboring zone search (1007), such as Fig.11D As shown. In some embodiments, the neighboring area search 1007 is used to identify one or more neighboring areas of the selected antenna area Z1 that can be activated to increase the amount of power delivered to the wireless power receiver. This may occur, for example, when the wireless power receiver is located at a boundary between adjacent antenna areas of the near-field charging pad (e.g., at an intersection between two antenna areas, three antenna areas, or four antenna areas). When performing the neighboring area search 1007, the near-field charging pad identifies (1142) neighboring antenna areas (ZA) of the selected antenna area Z1. In some embodiments, identifying the neighboring areas (ZA) includes identifying up to five neighboring areas.

[0203] Next, the near field charging pad pairs the selected antenna area Z1 with each identified adjacent area (1144) and scans across all antenna tuning combinations (1146) and across all available frequencies (and possible other transmission characteristics) (1148). Thereafter, the near field charging pad selects (1150) a combination of antenna areas from the adjacent areas (ZA). For example, the near field charging pad may determine that the amount of power delivered by the selected antenna area Z1 to the wireless power receiver is greater than the amount of power that any of the antenna areas alone can deliver to the wireless power receiver. In another example, the near field charging pad may determine that the selected antenna area Z1 and two (or three) other adjacent areas deliver the maximum amount of power to the wireless power receiver. When the desired antenna area combination is selected, the near field charging pad records the transmission characteristics used to produce the maximum amount of power delivered to the wireless power receiver. Performing a fine search and an adjacent area search is discussed in more detail above with reference to steps 924 to 932 of method 900.

[0204] After performing the fine search 1006 (and, if necessary, the neighboring area search 1007), the near field charging pad performs (1008) a power control routine, an example of which is shown in FIG. Fig.11E In some embodiments, the power control routine allows both the wireless power receiver and the near-field charging pad to continuously monitor the amount of power delivered to the wireless power receiver. In this way, adjustments to the wireless power transfer can be made based on feedback received from the wireless power receiver. For example, if the delivered power is below a configured threshold, the wireless power receiver can request a power increase from the near-field charging pad. Fig.11E Various operations that may be used to allow a receiver to request an increase or decrease in the amount of wireless power delivered to the receiver are illustrated, and a process performed by a near field charging pad to determine when to increase or decrease the amount of wireless power delivered to the receiver in response to the receiver's request to increase or decrease the amount of wireless power delivered is also illustrated.

[0205] The antenna element 120 (for example, see Figure 1B ) can also be configured to have multiple adaptive load terminals (eg, multiple adaptive load terminals 121) coupled at different positions along the corresponding antenna element 120. Fig.12 An example of an antenna element 120 having multiple adaptive load terminals is provided. Fig.12 FIG. 1 is a diagram showing a plurality of adaptive loads with a radio frequency charging pad according to some embodiments (which may be as described above with reference to FIG. 3 to FIG. 4 ). Figure 8 Schematic diagram of a transmitting antenna element (unit cell) of a radio frequency charging pad 1200 (part of an array of such antennas described in the specification). In some embodiments, the radio frequency charging pad 1200 includes one or more antenna elements 1201 (which may be, for example, Figure 3B , Figure 4, FIG. 6A to FIG. 6E , 7A to 7D and Figure 8 Each antenna element 1201 is connected to a corresponding power amplifier (PA) switching circuit 1208 (which may be any antenna element shown). Figure 3A The power amplifier switching circuit 103 is powered / fed by a corresponding one of the switching circuits in the PA switching circuit 103, and the power amplifier switching circuit can be connected to a corresponding power amplifier 1208 or a power source at the first end of the antenna element 1201.

[0206] In some embodiments, the input circuitry including power amplifier 1208 may additionally include a device that can change the frequency of the input signal or a device that can operate at multiple frequencies simultaneously, such as an oscillator or a frequency modulator.

[0207] In some embodiments, each antenna element 1201 of the RF charging pad 1200 includes a plurality of corresponding adaptive load terminals 1202 (e.g., 1202a, 1202b, 1202c, ..., 1202n) at a plurality of locations within the corresponding antenna element 1201. In some embodiments, the antenna element 1201 includes a conductive line forming a meander line pattern (as described above with reference to FIG. 3, Figure 4 and Figure 6 to Figure 8 In some embodiments, each of the plurality of adaptive load terminals 1202 of the antenna element 1201 is located at a different position on the meandering conductive line of the antenna element 1201, such as Fig.12 shown.

[0208] In some embodiments, meander line antenna element 1201 includes a conductive wire having multiple turns in a plane. In some embodiments, the multiple turns may be square turns, such as Fig.12 , as shown in the antenna element 1201 in the meander line antenna element 1201. In some embodiments, the multiple turns can be rounded edge turns. The conductive line can also have segments of different widths, for example, a segment 1206 having a first width and a short length segment 1207 having a second width less than the first width. In some embodiments, at least one of the adaptive load terminals 1202a is positioned at one of the short length segments (e.g., the short length segment 1207), and another adaptive load terminal is positioned at any position at one of the segments 1206 having the first width. In some embodiments, at least one of the adaptive load terminals 1202 is positioned or connected anywhere on the width segment, for example, in the middle of the width segment of the meander line antenna element 1201. In some embodiments, the last adaptive load terminal 1202n is located at the second end of the conductive line (as described above with reference to FIG. 3, Figure 4 and Figure 6 to Figure 8In some embodiments, in certain designs and optimizations, the adaptive load terminal is not necessarily located at the second end of the meander line antenna element 1201, but may be located anywhere on the antenna element 1201.

[0209] In some embodiments, the RF charging pad 1200 also includes a central processing unit 1210 (also referred to herein as processor 1210) or communicates with the central processing unit. In some embodiments, the processor 1210 is configured to control the RF signal frequency for each adaptive load terminal 1202 and control the impedance value at each adaptive load terminal 1202, for example, by communicating with multiple load pick-ups or adaptive loads 1212 (e.g., 1212a, 1212b, 1212c, ..., 1212n) (as described above with reference to Figure 3A and Figure 3B load picker or adaptive load 106 discussed in).

[0210] In some embodiments, an electronic device (e.g., a device that includes a receiver 1204 as an internal or externally connected component, such as a remote device placed on top of a charging pad 1200, which may be integrated into the housing of a streaming device or projector) uses energy transmitted from one or more RF antenna elements 1201 of the charging pad 1200 to the receiver 1204 to charge a battery and / or directly power the electronic device.

[0211] In some embodiments, the adaptive load terminals 1202 at a specific area or selected location of the antenna element 1201 (e.g., an area on the antenna element 1201 below where the electronic device to be charged (with an internally or externally connected RF receiver 1204) is placed on the charging pad) are optimized to maximize the power received by the receiver 1204. For example, the CPU 1210, upon receiving an indication that an electronic device with an internally or externally connected RF receiver 1204 has been placed on the pad 1200 in a specific area on the antenna element 1201, can adjust the plurality of adaptive loads 1212 (e.g., adaptive loads 1212a, 1212b, 1212c, ..., 1212n) respectively coupled to the adaptive terminals 1202 to maximize the power delivered to the RF receiver 1204. Adjusting a set of adaptive loads 1212 can include the CPU 1210 commanding one or more adaptive loads to try various impedance values ​​for one or more adaptive load terminals 1202 coupled to different locations of the antenna element 1201. Additional details regarding adjusting adaptive loads are provided above and are not repeated here for the sake of brevity.

[0212] The effective impedance value (Z) at a specific location / portion of the conductive line of the antenna element 1201 有效 ) is affected by many variables and can be manipulated by adjusting the configuration of the adaptive load terminal 1212 coupled to various locations on the antenna element 1201. In some embodiments, the effective impedance value (Z 有效 1204) and portion 1227 (which is formed by the remainder of transmit antenna element 1201 and terminal 1202n) and ends at the connection of TX antenna 1201 to adaptive load 1212n (e.g., terminal 1202n) will change based on the location of receiver 1204 on TX antenna 1201 and based on a set of selected loads provided by adaptive load 1212 at various locations within portion 1227. In some embodiments, the selected loads are optimized by adaptive load 1212 (in conjunction with processor 1210) to tune Z in such a manner that Z is 有效 : The energy transmitted between the terminal 1203 and the receiver 1204 is maximized (for example, 75% or more (such as 98%) of the energy emitted by the antenna element of the pad 1200 is received by the RF receiver 1204), while the energy transmission from the terminal 1203 to the terminal 1202n can also be kept at a minimum (for example, less than 25% (including as little as 2%) of the energy emitted by the antenna element of the pad 1200 that is not received by the RF receiver 1204 and ultimately reaches the terminal located in the portion 1227 or is ultimately reflected back).

[0213] In some embodiments, selected ones of the plurality of adaptive loads 1212 are used on the antenna element 1201 (by the processor 1210) to adjust the impedance and / or frequency of the antenna element 1201. In one example, reference Fig.12 , only the adaptive load terminals 1202a and 1202c are connected to the adaptive loads 1212a and 1212c, respectively, at a specific time point, while the adaptive load terminals 1202b and 1202n are disconnected at the specific time point. Fig.12, only adaptive load terminals 1202a and 1202n are connected to adaptive loads 1212a and 1212n, respectively, at a particular point in time, while adaptive load terminals 1202b and 1202c are disconnected at the particular point in time. In some embodiments, all adaptive load terminals 1202 are connected to their respective adaptive loads 1212 at a particular point in time. In some embodiments, none of the adaptive load terminals 1202 are connected to their respective adaptive loads 1212 at a particular point in time. In some embodiments, the impedance value of each adaptive load 1212 connected to a selected adaptive load terminal 1212 is individually adjusted to optimize energy transfer.

[0214] In an embodiment where a meander line antenna has been optimized for multi-band operation, Figure 3B Multiple adaptive load configurations within a single antenna element also enable wider frequency band adjustment compared to a single adaptive load configuration within a single antenna element described in . Multiple adaptive load configurations within a single antenna element further enhance multi-band operation of a single antenna element. For example, a single antenna element 1201 having multiple adaptive load terminals can operate at a wider frequency band than a corresponding antenna element configured with one adaptive load terminal.

[0215] In some embodiments, adjusting the set of adaptive loads 1212 also includes or alternatively includes the CPU 1210 causing the set of antenna elements to transmit RF signals at various frequencies until a frequency is found that transmits a maximum amount of energy to the RF receiver 1204. In some embodiments, for example, one of the antenna elements transmits RF signals at a first frequency, while another of the antenna elements transmits RF signals at a second frequency different from the first frequency. In some embodiments, adjusting the impedance value and / or the frequency at which the set of antenna elements transmits causes a change in the amount of energy transmitted to the RF receiver 1204. In this way, the amount of energy transmitted to the RF receiver 1204 that is maximized (e.g., to transmit at least 75% of the energy transmitted by the antenna elements of the pad 1200 to the receiver 1204, and in some embodiments, adjusting the impedance value and / or frequency can allow the receiver 1204 to receive up to 98% of the transmitted energy) can be received at any particular point on the pad 1200 where the RF receiver 1204 can be placed.

[0216] In some embodiments, the RF receiver 1204 is triggered when the amount of energy delivered to the RF receiver 1204 exceeds a predetermined threshold (e.g., 75% or more (such as up to 98%) of the transmitted energy is received), or by testing transmissions having multiple impedance and / or frequency values ​​and then selecting the impedance and frequency combination that results in the greatest amount of energy delivered to the RF receiver 1204 (also as described above with reference to FIG. 1 ). FIG. 3A to FIG. 3D), the CPU 1210 determines that the maximum amount of energy is being delivered to the RF receiver 1204. In some embodiments, the processor 1210 is connected to the receiver 1204 through a feedback loop (e.g., by exchanging messages using a wireless communication protocol such as Bluetooth Low Energy (BLE), WIFI, ZIGBEE, infrared beam, near field transmission, etc. for exchanging messages). In some embodiments, an adaptive scheme is employed to test various combinations of impedance values ​​of the adaptive impedance loads 1212 and RF frequencies in order to maximize the energy delivered to the RF receiver 1204. In such an embodiment, each adaptive load 1212 is configured to adjust the impedance value along a range of values, such as between 0 and infinity. In some embodiments, the adaptive scheme is employed when one or more RF receivers are placed on top of one of the antenna elements 1201.

[0217] In some embodiments, an adaptive scheme is employed to adaptively adjust the impedance value and / or the frequency of the RF signal(s) transmitted from the RF antenna(s) 1201 of the charging pad 1200 in order to determine which combinations of frequency and impedance result in the maximum energy being transferred to the RF receiver 1204. For example, a processor 1210 connected to the charging pad 1200 tries different frequencies (i.e., within the allowed operating frequency range or frequencies) by using different selected sets of adaptive loads 1212 at different locations of the antenna element 1201 (e.g., enabling or disabling certain adaptive loads 1212) in an attempt to adaptively optimize for better performance. For example, a simple optimization (in embodiments using relays to switch between these states) opens / disconnects or closes / shorts each load terminal to ground, and may also cause the RF antenna element 1201 to transmit at various frequencies. In some embodiments, for each combination of relay state (open or short) and frequency, the energy transferred to the receiver 1204 is monitored and compared to the energy transferred when other combinations are used. The combination that results in the greatest amount of energy transferred to the receiver 1204 is selected and used to continue transmitting one or more radio frequency signals to the receiver 1204 using one or more antenna elements 1201 .

[0218] In some embodiments, a single antenna element 1201 with multiple adaptive loads 1212 of a pad 1200 can be configured to operate in two or more different frequency bands (such as the above-mentioned ISM bands), for example, a first frequency band with a center frequency of 915 MHz and a second frequency band with a center frequency of 5.8 GHz. In these embodiments, employing an adaptive scheme can include: transmitting a radio frequency signal, and then adjusting the frequency by a first predetermined increment until a first threshold of the first frequency band is reached, and then adjusting the frequency by a second predetermined increment (which may or may not be the same as the first predetermined increment) until a second threshold of the second frequency band is reached. In some embodiments, a single antenna element can operate at multiple different frequencies within one or more frequency bands. For example, a single antenna element 1201 can be configured to transmit at 902 MHz, 915 MHz, 928 MHz (in the first frequency band) and then at 5.795 GHz, 5.8 GHz, and 5.805 GHz (in the second frequency band). A single antenna element 1201 can operate in more than one frequency band, thereby acting as a multi-band antenna. A transmitter having at least one antenna element 1201 may be used as a multi-band transmitter.

[0219] In some embodiments, multiple antenna elements 1201, each with multiple adaptive loads 1212, may be configured within a specific transmission pad to allow the specific transmission pad to operate in two or more different frequency bands at the same time. For example, the first antenna element 1201 of the specific transmission pad operates at a first frequency or frequency band, the second antenna element 1201 of the specific transmission pad operates at a second frequency or frequency band, and the third antenna element 1201 of the specific transmission pad operates at a third frequency or frequency band, and the fourth antenna element 1201 of the specific transmission pad operates at a fourth frequency or frequency band, and these four frequency bands are different from each other. In this way, the specific transmission pad is configured to operate in multiple different frequency bands.

[0220] In some embodiments, the transmitters described herein may transmit wireless power within one frequency or frequency band and transmit data and exchange data with a receiver within another frequency or frequency band.

[0221] Different antenna elements operating at different frequencies can maximize energy transfer efficiency when smaller devices are charged at a higher frequency and larger devices are charged at a lower frequency on the same charging pad. For example, devices that require a higher amount of power, such as mobile phones, may also have more room to include a larger antenna, making a lower frequency of 900 MHz a suitable band. In comparison, smaller devices, such as earbud headphones, may require a small amount of power and may also have less space available for a longer antenna, making a higher frequency of 2.4 or 5.8 GHz a suitable band. This configuration allows for greater flexibility in the type and size of antennas included in the receiving device.

[0222] Now go to Fig.13 According to some embodiments, a flow chart of a method 1300 for charging an electronic device by radio frequency (RF) power transmission using at least one RF antenna having a plurality of adaptive loads is provided. Initially, in step 1302, a charging pad including a transmitter is provided, wherein the transmitter includes at least one RF antenna for transmitting one or more RF signals or waves (e.g., as described above with reference to Fig.12 And further including Figures 3 to Figure 8 The antenna element 1201 is an antenna designed and capable of emitting radio frequency electromagnetic waves. In some embodiments, an array of radio frequency antenna elements 1201 are arranged adjacent to each other in a single plane, in a stack, or in a combination thereof, thereby forming a radio frequency charging pad 1200 (as shown in FIG. FIG. 6A to FIG. 6E , 7A to 7D and Figure 8 In some embodiments, the RF antenna elements 1201 each include an antenna input terminal (eg, as described above with reference to Fig.12 The first terminal 1203 discussed above) and multiple antenna output terminals (eg, Fig.12 In some embodiments, the antenna element 1201 includes conductive wires that form a meander line arrangement (as shown in FIGS. 3 to 4). Figure 4 and Figure 6 to Fig.12 The plurality of adaptive load terminals 1202 are located at different positions of the conductive line of the antenna element 1201.

[0223] In some embodiments, the transmitter further includes a power amplifier (eg, Fig.12 Some embodiments further include a PA 1208 electrically coupled to the plurality of antenna output terminals (eg, Fig.12 In some embodiments, the transmitter includes at least one processor (e.g., a processor configured to be electrically coupled to a power input terminal of a power supply and configured to control at least one electrical signal sent to the antenna. Fig.12 The processor 1210 and FIG. 3A to FIG. 3B In some embodiments, the at least one processor is further configured to control the frequency and / or amplitude of at least one signal sent to the antenna.

[0224] In some embodiments, each RF antenna of the transmitter includes: a conductive wire forming a meander line pattern; a first terminal (e.g., terminal 1203) at a first end of the conductive wire, the first terminal being used to receive a current flowing through the conductive wire at a frequency controlled by one or more processors; and a plurality of adaptive load terminals (e.g., terminal 1202) at a plurality of locations on the conductive wire that are different from the first terminal, the plurality of adaptive load terminals being coupled to corresponding components (e.g., terminals 1203) that are controlled by the one or more processors and that allow modification of an impedance value of the conductive wire. Fig.12 In some embodiments, the conductive line is arranged on or within the first antenna layer of the multi-layer substrate. Also in some embodiments, the second antenna is arranged on or within the second antenna layer of the multi-layer substrate. Finally, some embodiments also provide a ground plane arranged on or within the ground plane layer of the multi-layer substrate.

[0225] In some embodiments, a receiver (e.g., reference Fig.12 3). The receiver also includes one or more RF antennas for receiving RF signals. In some embodiments, the receiver includes at least one rectenna that converts the one or more RF signals into usable power to charge a device that includes the receiver 1204 as an internal or external connection component (see also reference 3). Figure 5 In use, the receiver 1204 is placed within a near-field RF distance from at least one antenna of a transmitter or charging pad. For example, the receiver may be placed on top of at least one RF antenna 1201 or on top of a surface adjacent to at least one RF antenna 1201, such as a surface of a charging pad 1200.

[0226] In step 1304 , one or more radio frequency signals are then transmitted via at least one radio frequency antenna 1201 .

[0227] Then, in step 1306, the monitoring system determines the amount of energy transmitted from at least one antenna 1201 to one or more RF receivers via one or more RF signals (also as discussed above). In some embodiments, this monitoring 1306 occurs at the transmitter, while in other embodiments, the monitoring 1306 occurs at the receiver, which sends data back to the transmitter via a return channel (e.g., via a wireless data connection using WIFI or Bluetooth). In some embodiments, the transmitter and receiver exchange messages via the return channel, and these messages can indicate the energy transmitted and / or received to inform the adjustments made at step 1308.

[0228] In some embodiments, in step 1308, a characteristic of the transmitter is adaptively adjusted to attempt to optimize the amount of energy delivered from the at least one RF antenna 1201 to the receiver. In some embodiments, this characteristic is the frequency of the one or more RF signals and / or the impedance of the transmitter. In some embodiments, the impedance of the transmitter is the impedance of an adjustable load. Also in some embodiments, at least one processor is further configured to control the impedance of a selected set of multiple adaptive loads 1212. Additional details and examples regarding impedance and frequency adjustment are provided above.

[0229] In some embodiments, at least one processor (e.g., Fig.12 The CPU 1210 in the embodiment dynamically adjusts the impedance of the adaptive load based on the monitored amount of energy transmitted to the RF receiver from the at least one antenna 1201. In some embodiments, at least one processor simultaneously controls the frequency of at least one signal sent to the antenna.

[0230] In some embodiments, a single antenna element 1201 with multiple adaptive loads 1212 of a pad 1200 can be dynamically adjusted by one or more processors to operate in two or more different frequency bands (such as the above-mentioned ISM bands) at the same time or at different times, for example, a first frequency band with a center frequency of 915 MHz and a second frequency band with a center frequency of 5.8 GHz. In these embodiments, employing an adaptive scheme may include: transmitting a radio frequency signal, and then adjusting the frequency by a first predetermined increment until a first threshold of the first frequency band is reached, and then adjusting the frequency by a second predetermined increment (which may or may not be the same as the first predetermined increment) until a second threshold of the second frequency band is reached. For example, a single antenna element 1201 can be configured to transmit at 902 MHz, 915 MHz, 928 MHz (in the first frequency band) and then at 5.795 GHz, 5.8 GHz, and 5.805 GHz (in the second frequency band). A single antenna element 1201 can operate in more than one frequency band, thereby acting as a multi-band antenna. A transmitter having at least one antenna element 1201 can be used as a multi-band transmitter.

[0231] In some embodiments, the charging pad or transmitter may include a Fig.12 One or more antenna elements 1201 with multiple adaptive loads as described in FIG. 3A to FIG. 3D One or more antenna elements 120 with an adaptive load as described in.

[0232] Figures 14A to 14D is a schematic diagram illustrating various configurations of a single antenna element that may operate at multiple frequencies or frequency bands within a radio frequency charging pad according to some embodiments. FIG. 14A to FIG. 14D As shown, the RF charging pad 100 ( FIG. 3A to FIG. 3B) or RF charging pad 1200 ( Fig.12 ) may include antenna element 120 (configured to have conductive line elements having different physical dimensions) Figure 3B ) or 1201( Fig.12 ).

[0233] For example, FIG. 14A to FIG. 14D Examples of structures of antenna elements are shown, each antenna element including conductive lines formed into different meander line patterns at different portions of the element. The conductive lines at different portions or locations of the element can have different geometric dimensions (such as width, or length, or trace gauge, or pattern, spacing between each trace, etc.) relative to other conductive lines within the antenna element. In some embodiments, the meander line pattern can be designed to have variable length and / or width at different locations of the pad (or individual antenna element). These configurations of meander line patterns allow for greater degrees of freedom, and therefore more complex antenna structures can be constructed, which allow for wider operating bandwidths and / or coupling ranges for individual antenna elements and RF charging pads.

[0234] In some embodiments, the antenna elements 120 and 1201 described herein may have FIG. 14A to FIG. 14D In some embodiments, FIG. 14A to FIG. 14D Each antenna element shown has an input terminal at one end of a conductive line ( Figure 1B 123 or Fig.12 1203) and at the other end or multiple locations of the conductive line as described above with an adaptive load ( Figure 1B 106 or Fig.12 At least one adaptive load terminal (1212a-n) of Figure 1B 121 or Fig.12 1202a-n in.

[0235] In some embodiments, FIG. 14A to FIG. 14D Each antenna element shown can operate at two or more different frequencies or two or more different frequency bands. For example, a single antenna element can operate at a first frequency band with a center frequency of 915 MHz at a first point in time and at a second frequency band with a center frequency of 5.8 GHz at a second point in time, depending on which frequency is provided at the input of each antenna element. In addition, FIG. 14A to FIG. 14D The shape of the meander line pattern shown is optimized to allow the antenna element to operate efficiently at a number of different frequencies.

[0236] In some embodiments, when the input terminal is provided with more than two different frequencies that can be superimposed, FIG. 14A to FIG. 14DEach antenna element shown can operate at two or more different frequencies or two or more different frequency bands simultaneously. For example, when two frequency bands with a first center frequency of 915 MHz and a second center frequency of 5.8 GHz are provided at the input end of the conductive line, a single antenna element can operate at a first frequency band with a center frequency of 915 MHz and a second frequency band with a center frequency of 5.8 GHz simultaneously. In another example, a single antenna element can operate at multiple different frequencies within one or more frequency bands.

[0237] In some embodiments, one or more processors ( FIG. 3A to FIG. 3B 110 or Fig.12 1210) as described above, adaptively adjusts the operating frequency of the antenna element based on the receiver antenna size, frequency or receiver loading on the charging pad and the adaptive load.

[0238] In some embodiments, compared to a more symmetrical meander line structure (e.g., Figure 3B , Figure 4 , FIG. 6A to FIG. 6B or Figure 8 )compared to, FIG. 14A to FIG. 14D Each antenna element shown having different meander patterns at different portions of the conductive line can operate more efficiently at multiple frequencies. For example, FIG. 14A to FIG. 14D The energy transfer efficiency at different operating frequencies of the antenna elements shown having different meander patterns at different portions of the conductive line can be improved by approximately at least 5%, and in some cases at least 60%, over that of a more symmetrical meander line structure element. For example, a more symmetrical meander line structure antenna element may transfer no more than 60% of the transmitted energy to a receiving device when operating at a new frequency other than the frequency for which the more symmetrical meander line structure antenna element was designed (e.g., if a more symmetrical meander line structure antenna element is designed to operate at 900 MHz, if it then transmits a signal at a frequency of 5.8 GHz, it may only be able to achieve an energy transfer efficiency of 60%). In contrast, antenna elements having different meander patterns (e.g., FIG. 14A to FIG. 14D Those shown) can achieve energy transfer efficiencies of 80% or more when operating at various frequencies. In this way, FIG. 14A to FIG. 14D The design of the antenna element shown ensures that a single antenna element can operate more efficiently at a variety of different frequencies.

[0239] Fig.15 is a diagram illustrating an example configuration of a single antenna element that can operate at multiple frequencies or frequency bands by adjusting the length of the antenna element in accordance with some embodiments.

[0240] In such Fig.15In some embodiments shown, at least one transmitting antenna element 1502 (as shown in FIGS. 3 to 4 ) of the one or more transmitting antenna elements of the RF charging pad 1500 is Figure 8 and Fig.13 14 ) has a first conductive segment 1504 (a first portion of a meandering conductive line, such as any of those described above for antenna elements 120 and 1201) and a second conductive segment 1506 (a second portion of a meandering conductive line, such as any of those described above for antenna elements 120 and 1201). In some embodiments, the first conductive segment includes an input terminal ( Figure 3B 123 in or Fig.12 1203 in ). In some embodiments, at least one transmit antenna element 1502 is configured to operate at a first frequency (e.g., 2.4 GHz) while the first conductive segment 1504 is not coupled to the second conductive segment 1506. In some embodiments, at least one transmit antenna element 1502 is configured to operate at a second frequency (e.g., 900 MHz) different from the first frequency while the first conductive segment is coupled to the second conductive segment.

[0241] In some embodiments, one or more processors ( FIG. 3A to FIG. 3B 110 or Fig.12 1210 in the embodiment) is configured to couple the first segment to the second segment and to indicate that the feeding element (eg FIG. 3A to FIG. 3B 108 and Fig.12 The one or more processors may also be configured to decouple the second conductive segment from the first conductive segment while instructing the feed element to generate a current having the first frequency instead of the second frequency, thereby allowing the antenna element 1502 to operate more efficiently at the first frequency. In some embodiments, the one or more processors are configured to determine whether to couple (or decouple) the conductive segments based on information received from a receiver (e.g., RX 104 or 1204) identifying the frequency at which the receiver is configured to operate (e.g., this frequency may be 900 MHz for a larger device with a longer receive antenna, and this frequency may be 2.4 GHz for a smaller device with a small receive antenna).

[0242] In some embodiments, here Fig.15The coupling described in the foregoing can be implemented by directly connecting two different segments of a single antenna element 1502 while bypassing the conductive line between the two connection points or two different segments. In some embodiments, coupling can be implemented between more than two different segments of the antenna element 1502. The coupling of different portions or segments of a single meander line antenna element 1502 can effectively change the size or length of the conductive line of the antenna element 1502 and thus enable the single antenna element 1502 to operate at different frequencies. A single antenna element 1502 can also operate at more than one frequency band, thereby acting as a multi-band antenna.

[0243] All of these examples are non-limiting, and any number of combinations and multi-layer structures may be implemented using the example structures described above.

[0244] Further embodiments also include various subsets of the above embodiments, including FIGS. 1 to 2 Fig.15 The embodiments in the drawings may be combined or otherwise rearranged in various embodiments, as will be readily apparent to those skilled in the art upon reading this disclosure.

[0245] The terms used in the specification of the present invention herein are only used for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the appended claims, the singular forms "a", "an" and "the" are intended to also include plural forms, unless the context clearly indicates otherwise. It will also be understood that the term "and / or" used herein refers to and encompasses any and all possible combinations of one or more of the associated enumerated items. It will be further understood that when the terms "comprises" and / or "comprising" are used in this specification, the presence of the features, steps, operations, elements and / or parts of the specified statements is not excluded, but the presence or addition of one or more other features, steps, operations, elements, parts and / or their groups is not excluded.

[0246] It will also be understood that although the terms "first," "second," etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are merely used to distinguish one element from another. For example, a first zone may be referred to as a second zone, and similarly, a second zone may be referred to as a first zone without changing the meaning of the description, as long as all occurrences of "first zone" are renamed consistently and all occurrences of "second zone" are renamed consistently. The first zone and the second zone are both zones, but they are not the same zone.

[0247] For the purpose of explanation, the foregoing description has been described with reference to specific embodiments. However, the above illustrative discussion is not intended to be exhaustive or to limit the invention to the precise form disclosed. In view of the above teachings, many modifications and variations are possible. These embodiments are selected and described in order to best explain the principles of the invention and its practical application, thereby enabling others skilled in the art to best utilize the present invention and various embodiments with various modifications suitable for the intended specific use.

Claims

1. A radio frequency (RF) charging pad, comprising: at least one processor configured to monitor an amount of energy transferred from the RF charging pad to a radio frequency receiver of an electronic device; as well as one or more transmit antenna elements in communication with the at least one processor and configured to transmit radio frequency signals to the radio frequency receiver of the electronic device, each respective transmit antenna element comprising: a conductive line, the conductive line forming a zigzag line pattern; a first terminal at a first end of the conductive line and for receiving current flowing through the conductive line at a frequency controlled by the at least one processor; and a second terminal different from the first terminal, the second terminal being at a second end of the conductive line opposite the first end of the conductive line, the second terminal being coupled to a component controlled by the at least one processor and allowing modification of the impedance value at the second terminal, wherein the at least one processor is configured to adaptively adjust the frequency and / or the impedance value to optimize the amount of energy transmitted from the one or more transmitting antenna elements to the radio frequency receiver of the electronic device; and Wherein, the at least one processor is further configured to: In response to determining that the RF charging pad is to transfer energy to radio frequency receivers of at least two electronic devices, adaptively adjusting the frequency and / or the impedance value so that the one or more transmitting antenna elements: Operate simultaneously in at least two different frequency bands; and The amount of energy delivered from the one or more transmit antenna elements to the radio frequency receivers of the at least two electronic devices is simultaneously optimized.

2. The RF charging pad of claim 1, wherein: The electronic device is placed on top of the surface of the RF charging pad.

3. The RF charging pad according to any one of claims 1 to 2, wherein: The component is a mechanical relay coupled to the second terminal for switching the second terminal between an open circuit state and a short circuit state, and the impedance value is adaptively adjusted at the second terminal of the corresponding transmitting antenna element by opening or closing the mechanical relay to switch between an open circuit or a short circuit, respectively.

4. The RF charging pad according to any one of claims 1 to 2, wherein: The component is an application specific integrated circuit ASIC, and the impedance value is adaptively adjusted along a range of values ​​by the ASIC.

5. The RF charging pad according to any one of claims 1 to 2, wherein: Adaptively adjusting the frequency includes adjusting the frequency in predetermined increments.

6. The RF charging pad according to any one of claims 1 to 2, wherein: Adaptively adjusting the frequency and / or the impedance value includes: adaptively adjusting the frequency and the impedance value to determine a maximum amount of energy transmitted to the RF receiver of the electronic device, and once the maximum amount of energy is determined, transmitting the RF signal at the frequency and the impedance value that produce the maximum amount of energy transmitted to the RF receiver.

7. The RF charging pad according to any one of claims 1 to 2, wherein: The at least one processor monitors an amount of energy delivered to the radio frequency receiver based at least in part on information received from the electronic device identifying energy received at the radio frequency receiver from the radio frequency signal.

8. The RF charging pad of claim 7, wherein: The information received from the electronic device reporting the received energy is transmitted using a short range communication protocol.

9. The RF charging pad of claim 8, wherein: The short-range communication protocol is Bluetooth Low Energy BLE.

10. The RF charging pad according to any one of claims 1 to 2, wherein: The at least one processor monitors the transferred energy based at least in part on an amount of energy detected at the second terminal and not received by the radio frequency receiver of the electronic device.

11. An electronic device having a radio frequency (RF) charging pad embedded therein, wherein: The RF Charging Pad Arranged according to any one of claims 1 to 10.

12. A radio frequency (RF) charging pad, comprising: one or more processors configured to monitor an amount of energy transferred from the RF charging pad to a radio frequency receiver of an electronic device; as well as One or more transmit antenna elements, the one or more transmit antenna elements configured to communicate with the one or more processors and to transmit radio frequency signals to the radio frequency receiver of the electronic device, each respective transmit antenna element comprising: a conductive line, the conductive line forming a zigzag line pattern; an input terminal at a first end of the conductive line and for receiving current flowing through the conductive line at a frequency controlled by the one or more processors; and a plurality of adaptive load terminals distinct from the input terminal and distinct from each other, the plurality of adaptive load terminals at a plurality of locations on the conductive line, the plurality of locations on the conductive line including a second end of the conductive line opposite the first end of the conductive line, each respective adaptive load terminal of the plurality of adaptive load terminals being coupled to a respective component configured to be controlled by the one or more processors and configured to allow modification of a respective impedance value at each respective adaptive load terminal, wherein the one or more processors are configured to adaptively adjust at least one of the frequency and the corresponding impedance value at one or more of the plurality of adaptive load terminals to optimize the amount of energy delivered from the one or more transmit antenna elements to the radio frequency receiver of the electronic device; and Wherein, the one or more processors are further configured to: In response to determining that the RF charging pad is to transfer energy to radio frequency receivers of at least two electronic devices, adaptively adjusting the frequency and / or the corresponding impedance value so that the one or more transmitting antenna elements: Operate simultaneously in at least two different frequency bands; and The amount of energy delivered from the one or more transmit antenna elements to the radio frequency receivers of the at least two electronic devices is simultaneously optimized.

13. The RF charging pad of claim 12, wherein: The frequency is in a first frequency band, and at least one of the one or more transmit antenna elements is configured to operate in a second frequency band based on adaptive adjustment by the one or more processors of corresponding impedance values ​​at one or more of the plurality of adaptive load terminals of the at least one transmit antenna element.

14. The RF charging pad as claimed in any one of claims 12 to 13, further comprising: an input circuit coupled to the one or more processors and configured to provide current to the input terminal at the first end of the conductive line, Wherein the one or more processors are configured to adaptively adjust the frequency by instructing the input circuit to generate a current having a new frequency different from the frequency.

15. The RF charging pad as claimed in any one of claims 12 to 13, wherein: The one or more processors are configured to adaptively adjust the frequency by instructing the feed element to generate current having a plurality of different frequencies determined using predetermined increments.

16. The RF charging pad as claimed in any one of claims 12 to 13, wherein: a respective conductive line for at least one of the one or more transmitting antenna elements having a respective meander line pattern that allows the at least one transmitting antenna element to efficiently transmit radio frequency signals having at least one of the frequency and a new frequency different from the frequency, at least two adjacent segments of said respective conductive lines having said respective meander line patterns have different geometric dimensions relative to each other, and When the at least one transmitting antenna element is configured to transmit a radio frequency signal having at least one of the frequency and the new frequency, the corresponding conductive lines have a length that remains the same.

17. The RF charging pad as claimed in any one of claims 12 to 13, wherein: At least one of the one or more transmitting antenna elements has a first section and a second section, the first section including the input terminal, and the at least one transmitting antenna element is configured to: operating at the frequency when the first segment is not coupled to the second segment, and operating at a new frequency different from the frequency when the first segment is coupled to the second segment; and The one or more processors are configured to couple the first segment to the second segment while instructing the feed element to generate current having the new frequency different from the frequency.

18. The RF charging pad as claimed in any one of claims 12 to 13, wherein: The one or more processors are configured to: adaptively adjusting at least one of the frequency and the corresponding impedance value associated with a first transmit antenna element of the one or more transmit antenna elements so that the first transmit antenna element operates in a first frequency band, and At least one of the frequency and the corresponding impedance value associated with a second transmit antenna element of the one or more transmit antenna elements is adaptively adjusted to cause the second transmit antenna element to operate in a second frequency band, wherein the first frequency band is different from the second frequency band.

19. The RF charging pad as claimed in any one of claims 12 to 13, wherein: The electronic device is placed in contact with or in proximity to the top surface of the RF charging pad.

20. The RF charging pad as claimed in any one of claims 12 to 13, wherein: The corresponding component is a mechanical relay coupled to the corresponding adaptive load terminal and used to switch the corresponding adaptive load terminal between an open circuit state and a short circuit state, and the corresponding impedance value is adaptively adjusted at the corresponding adaptive load terminal of the corresponding transmitting antenna element by opening or closing the mechanical relay to switch between an open circuit or a short circuit, respectively.

21. The RF charging pad as claimed in any one of claims 12 to 13, wherein: The corresponding component is an application specific integrated circuit ASIC, and the corresponding impedance value is adaptively adjusted by the ASIC within a range of values.

22. The RF charging pad as claimed in any one of claims 12 to 13, wherein: The one or more processors are configured to: adaptively adjusting at least one of the frequency and the corresponding impedance value by adaptively adjusting the frequency and the corresponding impedance value at one or more of the plurality of adaptive load terminals to determine a relative maximum amount of energy delivered to the radio frequency receiver of the electronic device, and Once the maximum amount of energy is determined, each of the one or more transmit antenna elements is caused to transmit the radio frequency signal accordingly at a corresponding frequency that results in a maximum amount of energy transferred to the radio frequency receiver and using a corresponding impedance value that results in a maximum amount of energy transferred to the radio frequency receiver.

23. The RF charging pad of any one of claims 12 to 13, wherein: The one or more processors monitor an amount of energy delivered to the radio frequency receiver based at least in part on information received from the electronic device, the information identifying energy received from the radio frequency signal at the radio frequency receiver.

24. The RF charging pad of claim 23, wherein: The information identifying the received energy received from the electronic device is transmitted using a wireless communication protocol.

25. The RF charging pad of claim 24, wherein: The wireless communication protocol is Bluetooth Low Energy BLE.

26. The RF charging pad of any one of claims 12 to 13, wherein: The one or more processors monitor an amount of energy delivered based at least in part on an amount of energy detected at a corresponding adaptive load terminal.

27. A method for charging an electronic device by radio frequency (RF) power transmission, the method comprising: A charging pad is provided that includes a transmitter, the transmitter including one or more radio frequency antennas, wherein each of the one or more radio frequency antennas includes: a conductive line, the conductive line forming a zigzag line pattern; an input terminal at a first end of the conductive line and for receiving a current flowing through the conductive line at a frequency controlled by one or more processors; and a plurality of adaptive load terminals distinct from the input terminal and distinct from each other, the plurality of adaptive load terminals at a plurality of locations on the conductive line, the plurality of locations on the conductive line including a second end of the conductive line opposite the first end of the conductive line, each respective adaptive load terminal of the plurality of adaptive load terminals coupled to a respective component configured to be controlled by the one or more processors and configured to allow modification of a respective impedance value at each respective adaptive load terminal; transmitting one or more radio frequency signals via the one or more radio frequency antennas; monitoring an amount of energy transmitted from the one or more RF antennas to an RF receiver via the one or more RF signals; and adaptively adjusting a characteristic of the transmitter using the one or more processors of the transmitter to optimize the amount of the energy delivered from the one or more RF antennas to the RF receiver, wherein the characteristic is selected from the group consisting of: (i) a frequency of the one or more RF signals, (ii) an impedance of the transmitter, and (iii) a combination of (i) and (ii), and further wherein the impedance of the transmitter is adaptively adjusted using the one or more processors of the transmitter at corresponding one or more of the plurality of adaptive load terminals of the one or more RF antennas; and Wherein, the method further comprises: In response to determining that the charging pad is to transfer energy to radio frequency receivers of at least two electronic devices, adaptively adjusting the characteristics of the transmitter using the one or more processors of the transmitter so that the one or more radio frequency antennas: Operate simultaneously in at least two different frequency bands; and The amount of energy transmitted from the one or more radio frequency antennas to the radio frequency receivers of the at least two electronic devices is simultaneously optimized.

28. The method of claim 27, wherein: The frequency is in a first frequency band, and at least one of the one or more RF antennas is configured to operate in a second frequency band based on adaptive adjustment of corresponding impedance values ​​at one or more of the multiple adaptive load terminals of the at least one RF antenna by the one or more processors.

29. The method of any one of claims 27 to 28, wherein: a respective conductive line for at least one of the one or more radio frequency antennas having a respective meander line pattern that allows the at least one radio frequency antenna to efficiently transmit the one or more radio frequency signals having at least one of the frequency and the new frequency, at least two adjacent segments of said respective conductive lines having said respective meander line patterns have different geometric dimensions relative to each other, and When the at least one radio frequency antenna is configured to transmit the one or more radio frequency signals having at least one of the frequency and the new frequency, the respective conductive lines have lengths that remain the same.

30. The method of any one of claims 27 to 28, wherein: At least one of the one or more radio frequency antennas has a first section and a second section, the first section includes the input terminal, and the at least one radio frequency antenna is configured as: operating at the frequency when the first segment is not coupled to the second segment, and operating at a new frequency when the first segment is coupled to the second segment; and The one or more processors are configured to couple the first segment to the second segment while instructing a feed element at the input terminal to generate a current having the new frequency different from the frequency.

31. A non-transitory computer readable storage medium comprising executable instructions that, when executed by one or more processors coupled to a radio frequency (RF) charging pad comprising one or more transmit antenna elements, cause the one or more processors to: monitoring an amount of energy transferred from the RF charging pad to a radio frequency receiver of an electronic device; in communication with the one or more transmit antenna elements of the radio frequency receiver for transmitting radio frequency signals to the electronic device, each respective transmit antenna element comprising: a conductive line, the conductive line forming a zigzag line pattern; an input terminal at a first end of the conductive line and for receiving current flowing through the conductive line at a frequency controlled by the one or more processors; and a plurality of adaptive load terminals distinct from the input terminal and from each other, the plurality of adaptive load terminals at a plurality of locations on the conductive line, the plurality of locations on the conductive line including a second end of the conductive line opposite the first end of the conductive line, each respective adaptive load terminal of the plurality of adaptive load terminals coupled to a respective component configured to be controlled by the one or more processors and configured to allow modification of a respective impedance value at each respective adaptive load terminal; and adaptively adjusting at least one of the frequency and the corresponding impedance value at one or more of the plurality of adaptive load terminals to optimize an amount of energy delivered from the one or more transmit antenna elements to the radio frequency receiver of the electronic device; Wherein, the executable instructions, when executed by the one or more processors, further cause the one or more processors to: In response to determining that the RF charging pad is to transfer energy to radio frequency receivers of at least two electronic devices, at least one of the frequency and / or the corresponding impedance value is adaptively adjusted at one or more adaptive load terminals of the plurality of adaptive load terminals so that the one or more transmitting antenna elements: Operate simultaneously in at least two different frequency bands; and The amount of energy delivered from the one or more transmit antenna elements to the radio frequency receivers of the at least two electronic devices is simultaneously optimized.

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