Apparatus and method for power control in a wireless power transmission system

Abstract

To provide a device and a method for performing authentication in a wireless power transmission system.SOLUTION: An authentication method in a wireless power transfer system according to the present specification includes a stage of receiving, from a target device, a first packet including instruction information regarding whether the target device supports an authentication function, a stage of sending an authentication request message to the target device when the target device supports the authentication function, a step of receiving an authentication response message including a certificate regarding wireless charging from the target device as a response to the authentication request message, and a stage of confirming the authentication of the target device on the basis of the authentication response message.SELECTED DRAWING: Figure 79

Description

Technical Field

[0001] The present invention relates to wireless power transmission, and more particularly to an apparatus and method for performing power control in a wireless power transmission system.

Background Art

[0002] Wireless power transmission technology is a technology for wirelessly transmitting power between a power source and an electronic device. As an example, wireless power transmission technology enables charging the battery of a wireless terminal such as a smartphone or a tablet by simply placing the wireless terminal on a wireless charging pad, providing better mobility, convenience, and safety compared to the existing wired charging environment that uses a wired charging connector. In addition to wireless charging of wireless terminals, wireless power transmission technology is attracting attention for replacing the existing wired power transmission environment in various fields such as electric vehicles, various wearable devices such as Bluetooth (registered trademark) earphones and 3D glasses, household appliances, furniture, underground facilities, buildings, medical devices, robots, and leisure.

[0003] The wireless power transmission method is also referred to as a non-contact power transmission method or a non-contactless power transmission method, or a wireless charging method. A wireless power transmission system includes a wireless power transmission device that supplies electrical energy by a wireless power transmission method, and a wireless power reception device that receives the electrical energy wirelessly supplied from the wireless power transmission device and supplies power to a power reception device such as a battery cell.

[0004] Wireless power transmission technologies are diverse, including methods that transmit power via magnetic coupling, radio frequency (RF), microwaves, and ultrasound. Methods based on magnetic coupling are further classified into magnetic induction and magnetic resonance. Magnetic induction transmits energy by utilizing a current induced in the receiving coil by a magnetic field generated from the transmitting coil's battery cell through electromagnetic coupling between the transmitting and receiving coils. Magnetic resonance is similar to magnetic induction in that it utilizes a magnetic field. However, magnetic resonance differs from magnetic induction in that resonance occurs when a specific resonant frequency is applied to the transmitting and receiving coils, and energy is transmitted through the phenomenon of magnetic field concentration at both ends of the transmitting and receiving sides.

[0005] Wireless power systems implemented in accordance with specific standard technologies can resolve safety issues in the event of overheating due to foreign objects. However, uncertified products that have not received product certification according to technical standards or specifications are circulating in the market, potentially exposing users to danger. Therefore, it is necessary to ensure stability and reliability by mutually authenticating the wireless power transmitter and wireless power receiver as genuine products during the pre- and post-wireless charging processes. [Prior art documents] [Patent Documents] [Patent Document 1] Japanese Unexamined Patent Publication No. 2017-229112 [Overview of the project] [Problems that the invention aims to solve]

[0006] The technical problem that the present invention aims to solve is to provide an apparatus and method for performing power control in a wireless power transmission system. [Means for solving the problem]

[0007] According to one aspect of the present invention, a wireless power transmitting device is provided. The device includes a power conversion unit configured to transmit wireless power to a wireless power receiving device by forming a magnetic coupling with the wireless power receiving device, and a communication / control unit configured to control the transmission of the wireless power and transmit or receive data based on communication with the wireless power receiving device.

[0008] Here, the communication / control unit receives a received power packet (RPP) from the wireless power receiver indicating the power value received by the wireless power receiver, and if there is data to be transmitted by the communication / control unit to the wireless power receiver, it transmits a bit pattern to the wireless power receiver in response to the RPP, requesting communication by the wireless power transmitter, and receives a polling packet from the wireless power receiver in response to the bit pattern, indicating the data to be transmitted.

[0009] In one aspect, the data to be transmitted may include power-related information for increasing or decreasing the level of the radio power.

[0010] In other respects, the RPP can indicate that the wireless power receiver is in mode 0.

[0011] In other respects, if the RPP indicates any of the remaining modes except mode 4, the communication / control unit may transmit the bit pattern.

[0012] Furthermore, in other respects, the bit pattern and the polling packet may each be 8 bits.

[0013] Another aspect of the present invention provides a power control method using a wireless power transmitter. The method includes the steps of: transmitting wireless power to a wireless power receiver by forming a magnetic coupling with the wireless power receiver; and controlling the transmission of the wireless power and transmitting or receiving data based on communication with the wireless power receiver.

[0014] Here, the steps of transmitting or receiving the data may include: receiving a received power packet (RPP) from the wireless power receiving device indicating a power value received by the wireless power receiving device; if there is data to be transmitted by the wireless power transmitting device to the wireless power receiving device, transmitting a bit pattern to the wireless power receiving device as a response to the RPP requesting communication by the wireless power transmitting device; and receiving a packet from the wireless power receiving device as a response to the bit pattern to poll for the data to be transmitted.

[0015] In one aspect, the data to be transmitted may include power-related information for increasing or decreasing the level of the radio power.

[0016] In other respects, the RPP can indicate that the wireless power receiver is in mode 0.

[0017] In other respects, if the RPP indicates any of the remaining modes except mode 4, the communication / control unit may transmit the bit pattern.

[0018] Furthermore, in other respects, the bit pattern and the polling packet may each be 8 bits.

[0019] According to yet another aspect of the present invention, a wireless power receiving device is provided. The device includes a power pickup unit configured to receive wireless power from a wireless power transmitting device by forming a magnetic coupling with the wireless power transmitting device, and a communication / control unit configured to control the transmission of the wireless power and transmit or receive data based on communication with the wireless power transmitting device.

[0020] Here, the communication / control unit can transmit a received power packet (RPP) indicating the power value received by the wireless power receiving device to the wireless power transmitting device, and if there is data to be transmitted by the wireless power transmitting device, it can receive a bit pattern from the wireless power transmitting device as a response to the RPP requesting communication by the wireless power transmitting device, and transmit a packet to the wireless power transmitting device as a response to the bit pattern to poll for the data to be transmitted.

[0021] In one aspect, the data to be transmitted may include power-related information for increasing or decreasing the level of the radio power.

[0022] In other respects, the RPP can indicate that the wireless power receiver is in mode 0.

[0023] In other respects, if the RPP indicates any of the remaining modes except mode 4, the communication / control unit can receive the bit pattern.

[0024] Furthermore, in other respects, the bit pattern and the polling packet may each be 8 bits.

[0025] According to still another aspect of the present invention, there is provided a power control method by a wireless power receiving device. The method includes forming a magnetic coupling with a wireless power transmitting device to receive wireless power from the wireless power transmitting device, and performing transmission control of the wireless power and transmission or reception of data based on communication with the wireless power transmitting device.

[0026] Here, the step of performing transmission or reception of the data may include transmitting a received power packet (RPP) indicating a power value received by the wireless power receiving device to the wireless power transmitting device, receiving a bit pattern from the wireless power transmitting device for requesting communication by the wireless power transmitting device as a response to the RPP when there is data to be transmitted by the wireless power transmitting device to the wireless power receiving device, and transmitting a packet for polling the data to be transmitted as a response to the bit pattern to the wireless power transmitting device.

[0027] In one aspect, the data to be transmitted may include power-related information for increasing or decreasing the level of the wireless power.

[0028] In another aspect, the RPP may indicate that the wireless power receiving device is in mode 0.

[0029] In still another aspect, when the RPP indicates the remaining modes except mode 4, the communication / control unit may receive the bit pattern.

[0030] In still another aspect, the bit pattern and the polling packet may each be 8 bits.

Advantages of the Invention

[0031] The present invention clearly provides essential elements for authentication between a wireless power transmitter and a wireless power receiver, such as the format of the wireless charging certificate, instructional information regarding the support of the authentication function, the timing between authentication-related procedures and wireless charging phases, authentication procedures and authentication messages, and lower-level protocols supporting the authentication procedures, thereby ensuring stability and reliability even during high-power wireless charging. [Brief explanation of the drawing]

[0032] [Figure 1] This is a block diagram of a wireless power system 10 according to one embodiment. [Figure 2] This is a block diagram of a wireless power system 10 according to another embodiment. [Figure 3] This document illustrates various embodiments of electronic devices that incorporate a wireless power transmission system. [Figure 4] This is a block diagram of a wireless power transmission system according to another embodiment. [Figure 5] This is a state transition diagram illustrating the wireless power transmission procedure. [Figure 6] A power control method according to one embodiment is shown. [Figure 7] This is a block diagram of a wireless power transmitter according to another embodiment. [Figure 8] Another embodiment of a wireless power receiving device is shown. [Figure 9] This shows a communication frame structure according to one embodiment. [Figure 10] This is the structure of a sink pattern according to one embodiment. [Figure 11] This shows the operating state of a wireless power transmitter and a wireless power receiver in shared mode according to one embodiment. [Figure 12] This is a block diagram showing a wireless charging certificate format according to one embodiment. [Figure 13a] This is a block diagram showing a wireless charging certificate format according to another embodiment. [Figure 13b] This is a block diagram showing a wireless charging certificate format according to another embodiment. [Figure 14] This is the performance packet structure of a wireless power transmission device according to one embodiment. [Figure 15] This is the performance packet structure of a wireless power transmitter according to another embodiment. [Figure 16] This is the packet structure of a wireless power receiving device according to one embodiment. [Figure 17] This is the packet structure of a wireless power receiving device according to another embodiment. [Figure 18] This flowchart shows the sequence of packets transmitted and received when a wireless power receiving device according to one embodiment performs authentication of a wireless power transmitting device (PTx by PRx). [Figure 19] This is an example of the message structure for GET_DIGESTS. [Figure 20] Here is another example of the message structure for GET_DIGESTS. [Figure 21] This diagram illustrates the physical packet structure to which DIGESTS is sent and how it is transmitted. [Figure 22] This is an example of the message structure for GET_CERTIFICATE. [Figure 23] This is an example of the physical packet structure and method used to transmit a certificate. [Figure 24] This is an example of the physical packet structure to which an authentication response message from a wireless power transmitter is sent, and a method for transmitting it. [Figure 25] This is an example of a CHALLENGE message structure. [Figure 26] This is an example of the physical packet structure to which CHALLENGE_AUTH is sent, and how to send it. [Figure 27] This flowchart shows the sequence of packets transmitted and received when a wireless power transmitter according to one embodiment performs authentication of a wireless power receiver (PRx by PTx). [Figure 28]This is an example of the message structure of GET_DIGESTS transmitted by a wireless power transmitter. [Figure 29] This is an example of the GET_CERTIFICATE message structure transmitted by a wireless power transmitter. [Figure 30] This is an example of the physical packet structure and method of transmitting a Certificate for a wireless power receiver. [Figure 31] This is an example of the structure of a CHALLENGE message transmitted by a wireless power transmitter. [Figure 32] This is an example of the physical packet structure and method of transmission for CHALLENGE_AUTH transmitted by a wireless power receiver. [Figure 33] This is an example of the physical packet structure to which an authentication response message from a wireless power receiver is sent, and a method for sending it. [Figure 34] This is another example of the physical packet structure to which an authentication response message from a wireless power receiver is sent, and how to transmit it. [Figure 35] This flowchart shows the sequence of packets transmitted and received when a wireless power transmitter according to another embodiment performs authentication of a wireless power receiver (PRx by PTx). [Figure 36] This diagram shows the structure of a packet transmitted by a wireless power receiver to a wireless power transmitter during in-band communication. [Figure 37] This diagram shows the structure of a packet transmitted by a wireless power transmitter to a wireless power receiver in in-band communication. [Figure 38] This figure shows the packet transmission and reception sequence between a wireless power receiver and a transmitter from a lower-level perspective according to one embodiment. [Figure 39] This figure shows the packet transmission and reception sequence between a wireless power receiver and a transmitter from a lower-level perspective according to another embodiment. [Figure 40] This is the structure of an extended control error packet according to one embodiment. [Figure 41]This is the structure of an end power transfer (EPT) packet according to one embodiment. [Figure 42] This is the structure of an extended received power packet according to one embodiment. [Figure 43] This figure shows the packet transmission and reception sequence between a wireless power receiver and a transmitter from a lower-level perspective according to one embodiment. [Figure 44] This figure shows a data transport mechanism according to one embodiment. [Figure 45] This figure shows data transport in another embodiment. [Figure 46] This is the structure of an ADT data packet (ADT_PRx Data Packet) related to a wireless power receiving device according to one embodiment. [Figure 47] This is the structure of an ADT response packet (ADT_PRx Response Packet) related to a wireless power receiving device according to one embodiment. [Figure 48] This is the structure of an ADT control packet (ADT_PRx Control Packet) related to a wireless power receiving device according to one embodiment. [Figure 49] This is the structure of an ADT data packet (ADT_PTx Data Packet) related to a wireless power transmission device according to one embodiment. [Figure 50] This is the structure of an ADT response packet (ADT_PTx Response Packet) related to a wireless power transmission device according to one embodiment. [Figure 51] This shows the structure of an ADT response / control packet (ADT_PTx Response / Control Packet) related to a wireless power transmission device according to one embodiment. [Figure 52] This is the structure of an ADT control packet (ADT_PTx Control Packet) related to a wireless power transmission device according to one embodiment. [Figure 53] This is a diagram showing a state machine related to ADT data packet recording (write) according to one embodiment. [Figure 54] This diagram illustrates the upper-level and high-level transmission sequences of the wireless power receiving device and the wireless power transmitting device during the exchange of ADT data packets according to one embodiment. [Figure 55] This diagram illustrates the upper-level and high-level transmission sequences of the wireless power receiver and wireless power transmitter during ADT data packet exchange according to another embodiment. [Figure 56] This diagram illustrates the upper-level and high-level transmission sequences of the wireless power receiver and wireless power transmitter during the exchange of ADT data packets according to another embodiment. [Figure 57] This figure illustrates the exchange sequence of ADT data packets related to an authentication request message according to one embodiment. [Figure 58] This figure illustrates the exchange sequence of ADT data packets related to authentication request messages according to another embodiment. [Figure 59] This figure illustrates the exchange sequence of ADT data packets related to authentication request messages according to another embodiment. [Figure 60] This figure illustrates the exchange sequence of ADT data packets related to authentication request messages according to another embodiment. [Figure 61] This figure illustrates the exchange sequence of ADT data packets related to authentication request messages according to another embodiment. [Figure 62] This figure illustrates the exchange sequence of ADT data packets related to an authentication response message according to one embodiment. [Figure 63] This figure illustrates the exchange sequence of ADT data packets related to authentication response messages according to another embodiment. [Figure 64] This figure illustrates the exchange sequence of ADT data packets related to authentication response messages according to another embodiment. [Figure 65] This figure illustrates the exchange sequence of ADT data packets related to authentication response messages according to another embodiment. [Figure 66]This figure illustrates the exchange sequence of ADT data packets related to authentication response messages according to another embodiment. [Figure 67] This diagram illustrates the upper-level and high-level transmission sequences of a wireless power transmitter and a wireless power receiver during the exchange of ADT data packets according to one embodiment. [Figure 68] This diagram illustrates the upper-level and high-level transmission sequences of the wireless power transmitter and wireless power receiver during ADT data packet exchange according to another embodiment. [Figure 69] This figure illustrates the exchange sequence of ADT data packets related to an authentication request message according to one embodiment. [Figure 70] This figure illustrates the exchange sequence of ADT data packets related to authentication request messages according to another embodiment. [Figure 71] This figure illustrates the exchange sequence of ADT data packets related to authentication request messages according to another embodiment. [Figure 72] This figure illustrates the exchange sequence of ADT data packets related to authentication request messages according to another embodiment. [Figure 73] This figure illustrates the exchange sequence of ADT data packets related to authentication request messages according to another embodiment. [Figure 74] This figure illustrates the exchange sequence of ADT data packets related to an authentication response message according to one embodiment. [Figure 75] This figure illustrates the exchange sequence of ADT data packets related to authentication response messages according to another embodiment. [Figure 76] This figure illustrates the exchange sequence of ADT data packets related to authentication response messages according to another embodiment. [Figure 77] This figure illustrates the exchange sequence of ADT data packets related to authentication response messages according to another embodiment. [Figure 78] This is the structure of GRP according to one embodiment. [Figure 79] This is a transmission sequence relating to power management initiated by a wireless power transmission device according to one embodiment. [Modes for carrying out the invention]

[0033] The term "wireless power" as used below refers to any form of energy associated with electric, magnetic, or electromagnetic fields transmitted from a wireless power transmitter to a wireless power receiver without the use of physical electromagnetic conductors. Wireless power is sometimes also called a wireless power signal and may refer to an oscillating magnetic flux enclosed by a primary and secondary coil. For example, power conversion in a system for wirelessly charging devices including mobile phones, cordless phones, iPods®, MP3 players, and headsets is described here. In general, the basic principles of wireless power transmission include, for example, methods of transmitting power by magnetic coupling, radio frequency (RF), microwaves, and ultrasound.

[0034] Figure 1 is a block diagram of a wireless power system 10 according to one embodiment.

[0035] As shown in Figure 1, the wireless power system 10 includes a wireless power transmitter 100 and a wireless power receiver 200.

[0036] The wireless power transmitter 100 receives power from an external power source (S) and generates a magnetic field. The wireless power receiver 200 uses the generated magnetic field to generate an electric current and receives power wirelessly.

[0037] Furthermore, in the wireless power system 10, the wireless power transmitter 100 and the wireless power receiver 200 can send and receive various types of information necessary for wireless power transmission. Here, communication between the wireless power transmitter 100 and the wireless power receiver 200 is performed using either in-band communication, which utilizes the magnetic field used for wireless power transmission, or out-band communication, which utilizes a separate communication carrier.

[0038] Here, the wireless power transmitter 100 is provided in a fixed or mobile form. Examples of fixed forms include being embedded in the ceiling or wall or furniture such as a table indoors, being implanted in outdoor locations such as parking lots, bus stops or subway stations, or being installed on means of transport such as vehicles or trains. A mobile wireless power transmitter 100 can be implemented as part of a mobile device of a movable weight and size, or as part of another device such as a laptop cover.

[0039] Furthermore, the wireless power receiver 200 must be interpreted as a comprehensive concept that includes various electronic devices equipped with batteries and various home appliances powered wirelessly instead of using power cables. Typical examples of wireless power receivers 200 include portable terminals, cellular phones, smartphones, personal digital assistants (PDAs), portable media players (PMPs), Wibro terminals, tablets, pablets, notebooks, digital cameras, navigation terminals, televisions, and electric vehicles (EVs).

[0040] In the wireless power system 100, there may be one or more wireless power receivers 200. In Figure 1, the wireless power transmitter 100 and the wireless power receiver 200 are shown to exchange power on a one-to-one basis, but as shown in Figure 2, it is also possible for one wireless power transmitter 100 to transmit power to multiple wireless power receivers 200-1, 200-2, ..., 200-M. In particular, when wireless power transmission is performed using a magnetic resonance method, one wireless power transmitter 100 can transmit power to multiple wireless power receivers 200-1, 200-2, ..., 200-M simultaneously by applying a simultaneous transmission method or a time-division transmission method.

[0041] Furthermore, although Figure 1 shows how the wireless power transmitter 100 immediately transmits power to the wireless power receiver 200, a separate wireless power transceiver or repeater can also be provided between the wireless power transmitter 100 and the wireless power receiver 200 to increase the wireless power transmission distance. In this case, power can be transmitted from the wireless power transmitter 100 to the wireless power transceiver, and the wireless power transceiver can then transmit power back to the wireless power receiver 200.

[0042] Hereinafter, the terms "wireless power receiver," "power receiver," and "receiver" as used herein refer to the wireless power receiving device 200. Similarly, the terms "wireless power transmitter," "power transmitter," and "transmitter" as used herein refer to the wireless power receiving and transmitting device 100.

[0043] Figure 3 shows various embodiments of electronic devices into which a wireless power transmission system is introduced.

[0044] Figure 3 shows a classification of electronic devices based on the amount of power transmitted and received by the wireless power transmission system. As shown in Figure 3, low-power (approximately 5W or less or approximately 20W or less) wireless charging methods can be applied to wearable devices such as smart watches, smart glasses, HMDs (Head Mounted Displays), and smart rings, as well as mobile electronic devices (or portable electronic devices) such as earphones, remote controls, smartphones, PDAs, and tablet PCs.

[0045] Medium- and small-sized home appliances such as laptops, robot vacuums, TVs, audio equipment, vacuum cleaners, and monitors can be charged using a medium-power (approximately 50W or less or approximately 200W or less) wireless charging method. Kitchen appliances such as blenders, microwave ovens, and electric rice cookers, as well as personal mobility devices (or electronic devices / means of transportation) such as wheelchairs, electric scooters, electric bicycles, and electric vehicles, can be charged using a high-power (approximately 2kW or less or 22kW or less) wireless charging method.

[0046] The aforementioned electronic devices / mobile devices (or those shown in Figure 1) may each include a wireless power receiver, which will be described later. Therefore, the aforementioned electronic devices / mobile devices can be charged by receiving power wirelessly from a wireless power transmitter.

[0047] The following description will focus on mobile devices to which the wireless power charging method is applied, but this is merely an embodiment, and the wireless charging method according to the present invention can be applied to the various electronic devices mentioned above.

[0048] Standards related to wireless power transmission include those of the WPC (Wireless Power Consortium), AFA (Air Fuel Alliance), and PMA (Power Matters Alliance).

[0049] The WPC standard defines a baseline power profile (BPP) and an extended power profile (EPP). The BPP pertains to wireless power transmitters and receivers that support 5W of power transmission, while the EPP pertains to wireless power transmitters and receivers that support power transmission in the range of greater than 5W but less than 30W.

[0050] Various wireless power transmitters and receivers using different power levels are covered by each standard and classified into different power classes (PCs) or categories.

[0051] For example, WPC classifies wireless power transmitters and receivers into power class (PC)-1, PC0, PC1, and PC2, and provides standard documentation for each PC. The PC-1 standard concerns wireless power transmitters and receivers that provide guaranteed power of less than 5W. Applications of PC-1 include wearable devices such as smartwatches.

[0052] The PC0 standard relates to wireless power transmitters and receivers that provide a guaranteed power of 5W. The PC0 standard includes EPPs with guaranteed power up to 30W. In-band (IB) communication is the mandatory communication protocol for PC0, but out-of-band (OBB) communication can also be used as an optional backup channel. Wireless power receivers can identify OOB support by setting an OOB flag in a configuration packet. Wireless power transmitters that support OOB can enter the OOB handover phase by sending a bit pattern for OOB handover in response to the configuration packet. The response to the configuration packet may be NAK, ND, or a newly defined 8-bit pattern. PC0 applications include smartphones.

[0053] The PC1 standard relates to wireless power transmitters and receivers providing guaranteed power of 30W to 150W. OOB is the essential communication channel for PC1, while IB is used for initialization and link establishment to OOB. The wireless power transmitter can enter the OOB handover phase by transmitting a bit pattern for OOB handover in response to a configuration packet. PC1 applications include laptops and power tools.

[0054] The PC2 standard relates to wireless power transmitters and receivers that provide guaranteed power of 200W to 2kW, and its applications include kitchen appliances.

[0055] Thus, PCs are distinguished by their power levels, and supporting compatibility between identical PCs is either optional or mandatory. Here, compatibility between identical PCs means that power can be transmitted and received between identical PCs. For example, if a wireless power transmitter (PCx) can charge a wireless power receiver having the same PCx, then compatibility between identical PCs can be considered maintained. Similarly, compatibility between different PCs can also be supported. Here, compatibility between different PCs means that power can be transmitted and received between different PCs. For example, if a wireless power transmitter (PCx) can charge a wireless power receiver having PCy, then compatibility between different PCs can be considered maintained.

[0056] Supporting compatibility between PCs is a crucial issue from both a user experience and infrastructure development perspective. However, maintaining compatibility between PCs presents various technical challenges, as outlined below.

[0057] In the case of compatibility between identical PCs, for example, a laptop charging wireless power receiver, which can only reliably charge when power is transmitted continuously, may have problems receiving power reliably from a power tool-type wireless power transmitter, even if it is on the same PC, because power is transmitted discontinuously. Furthermore, in the case of compatibility between different PCs, for example, if a wireless power transmitter with a guaranteed power of at least 200W transmits power to a wireless power receiver with a maximum guaranteed power of 5W, the receiver may be damaged due to overvoltage. As a result, it is difficult to use PCs as a representative / indicating indicator / standard for compatibility.

[0058] In the following, we define "profile" as a new indicator / criterion representing / indicating compatibility. That is, it can be interpreted that compatible and stable power transmission / reception are possible between wireless power transceivers having the same "profile," while power transmission / reception is impossible between wireless power transceivers having different "profiles." Profiles can be defined by whether or not they are compatible regardless of (or independently of) the power class and / or by the application.

[0059] For example, profiles can be broadly divided into four categories: i) mobile, ii) power tools, iii) kitchen, and iv) wearable.

[0060] For the "Mobile" profile, the PC can be defined as PC0 and / or PC1, the communication protocol / method as IB and OOB, and the operating frequency as 87-205kHz. Examples of applications include smartphones and laptops.

[0061] For the "Power Tools" profile, the PC can be defined as PC1, the communication protocol / method as IB, and the operating frequency as 87-145kHz. Examples of applications include power tools.

[0062] For the "Kitchen" profile, the PC can be defined as PC2, the communication protocol / method as NFC-based, and the operating frequency as less than 100kHz. Examples of applications include kitchen / home appliances.

[0063] For the "wearable" profile, the PC can be defined as PC-1, the communication protocol / method as IB, and the operating frequency as 87-205kHz. Examples of applications include wearable devices worn on the user's body.

[0064] Maintaining compatibility between identical profiles is essential, while maintaining compatibility between different profiles may be optional.

[0065] The aforementioned profiles (mobile profile, power tool profile, kitchen profile, and wearable profile) can be expressed by generalizing the first to nth profiles, and new profiles can be added / replaced by WPC standards and embodiments.

[0066] When profiles are defined in this way, wireless power transmitters selectively transmit power only to wireless power receivers with the same profile as themselves, enabling more stable power transmission. Furthermore, the burden on the wireless power transmitter is reduced, and the risk of damage to the wireless power receiver is mitigated because it will no longer attempt to transmit power to incompatible wireless power receivers.

[0067] PC1 within the "Mobile" profile can be defined by borrowing selective extensions such as OOB based on PC0, and in the case of the "Power Tools" profile, PC1 can be defined as a simply modified version of the "Mobile" profile. Furthermore, while previously defined to maintain compatibility between identical profiles, the technology can be developed in the direction of maintaining compatibility between different profiles. Wireless power transmitters or receivers can inform others of their profile in various ways.

[0068] The AFA standard refers to wireless power transmitters as PTUs (power transmitting units) and wireless power receivers as PRUs (power receiving units). PTUs are classified into multiple classes as shown in Table 1, and PRUs are classified into multiple categories as shown in Table 2.

[0069] [Table 1]

[0070] [Table 2]

[0071] As shown in Table 1, the maximum power output performance (capability) of a class n PTU is the P of that class. TX_IN_MAX The value is greater than or equal to the value. A PRU cannot draw more power than the power specified in that category.

[0072] Figure 4 is a block diagram of a wireless power transmission system according to another embodiment.

[0073] As shown in Figure 4, the wireless power transmission system 10 includes a mobile device 450 that receives power wirelessly and a base station 400 that transmits power wirelessly.

[0074] The base station 400 is a device that provides inductive or resonant power and may include at least one power transmitter 100 and a system unit 405. The power transmitter 100 can transmit and control inductive or resonant power. The power transmitter 100 may include a power conversion unit 110 that converts electrical energy into a power signal by generating a magnetic field with primary coils, and a communications and control unit 120 that communicates with and controls power transmission to the power receiver 200 to transmit power at an appropriate level. The system unit 405 can perform other operational controls of the base station 100, such as input power provisioning, control of multiple power transmitters, and user interface control.

[0075] The primary coil can generate an electromagnetic field using alternating current (AC) power (or voltage or current). When AC power (or voltage or current) of a specific frequency output from the power conversion unit 110 is applied to the primary coil, it can generate a magnetic field of a specific frequency. The magnetic field can be generated non-radiatively or radiatively, and the wireless power receiver 200 receives it and generates a current. In other words, the primary coil transmits power wirelessly.

[0076] In magnetic induction systems, the primary and secondary coils can take any suitable form, for example, copper wire wound around a highly permeable material such as ferrite or amorphous metal. The primary coil may also be called the primary core, primary winding, or primary loop antenna. The secondary coil, on the other hand, may also be called the secondary core, secondary winding, secondary loop antenna, or pickup antenna.

[0077] When using a magnetic resonance method, the primary and secondary coils are provided in the form of a primary and secondary resonant antenna, respectively. The resonant antenna can have a resonant structure including a coil and a capacitor. In this case, the resonant frequency of the resonant antenna is determined by the inductance of the coil and the capacitance of the capacitor. Here, the coil can be formed in the form of a loop, and a core can be placed inside the loop. The core can include a physical core such as a ferrite core or an air core.

[0078] Energy transmission between a primary and secondary resonant antenna can be achieved through magnetic field resonance. Resonance refers to the phenomenon where, when a near-field field corresponding to the resonant frequency is generated by one resonant antenna and other resonant antennas are located around it, the two resonant antennas couple up to each other, resulting in highly efficient energy transfer between them. When a magnetic field corresponding to the resonant frequency is generated between the primary and secondary resonant antennas, the primary and secondary resonant antennas resonate with each other. This allows the magnetic field to be focused towards the secondary resonant antenna with higher efficiency than when the magnetic field generated by the primary resonant antenna is radiated into free space, and therefore, energy can be transferred from the primary to the secondary resonant antenna with high efficiency. The magnetic induction method is implemented similarly to the magnetic resonance method, but in this case, the frequency of the magnetic field does not need to be the resonant frequency. Instead, the magnetic induction method requires matching between the loops constituting the primary and secondary coils, and the distance between the loops must be very small.

[0079] Although not shown in the diagram, the wireless power transmitter 1100 may further include a communication antenna. The communication antenna can transmit and receive communication signals using communication carriers other than magnetic field communication. For example, the communication antenna can transmit and receive communication signals such as Wi-Fi, Bluetooth (registered trademark), Bluetooth LE, ZigBee (registered trademark), and NFC.

[0080] The communication / control unit 120 can send and receive information with the wireless power receiver 200. The communication / control unit 120 may include at least one of either an IB communication module or an OOB communication module.

[0081] An IB communication module can transmit and receive information using magnetic waves with a specific center frequency. For example, the communication / control unit 120 can perform in-band communication by transmitting information via a primary coil by loading it onto a magnetic wave, or by receiving a magnetic wave containing information via a primary coil. In this case, modulation schemes such as binary phase shift keying (BPSK) or amplitude shift keying (ASK) and coding schemes such as Manchester coding or non-return-to-zero level (NZR-L) coding can be used to load information onto the magnetic wave or analyze a magnetic wave containing information. Using such IB communication, the communication / control unit 120 can transmit and receive information over distances of several meters at a data transmission rate of several kbps.

[0082] OOB communication modules can also perform out-of-band communication via a communication antenna. For example, the communication / control unit 120 can be provided as a short-range communication module. Examples of short-range communication modules include Wi-Fi, Bluetooth, Bluetooth LE, ZigBee, and NFC.

[0083] The communication / control unit 120 can control the overall operation of the wireless power transmitter 100. The communication / control unit 120 can perform calculations and processing of various information and control each component of the wireless power transmitter 100.

[0084] The communication / control unit 120 can be implemented in a computer or similar device using hardware, software, or a combination thereof. In hardware terms, the communication / control unit 120 can be provided in the form of an electronic circuit that processes electrical signals to perform control functions, and in software terms, it can be provided in the form of a program that drives the hardware communication / control unit 120.

[0085] The communication / control unit 120 can control the transmission power by controlling the operating point. The operating point to be controlled can be a combination of frequency (or phase), duty cycle, duty ratio, and voltage amplitude. The communication / control unit 120 can control the transmission power by adjusting at least one of the frequency (or phase), duty cycle, duty ratio, and voltage amplitude. In addition, the wireless power transmitter 100 can supply a constant power, and the wireless power receiver 200 can control the received power by controlling the resonant frequency.

[0086] The mobile device 450 includes a power receiver 200 that receives wireless power via a secondary coil, and a load 455 that receives and stores the power received by the power receiver 200 and supplies it to the device.

[0087] The wireless power receiving device 200 may include a power pickup unit 210 and a communications & control unit 220. The power pickup unit 210 receives wireless power via a secondary coil and converts it into electrical energy. The power pickup unit 210 rectifies the AC signal obtained via the secondary coil and converts it into a DC signal. The communications & control unit 220 controls the transmission and reception (power transfer and reception) of wireless power.

[0088] The secondary coil can receive wireless power transmitted from the wireless power transmitter 100. The secondary coil can receive power by utilizing the magnetic field generated by the primary coil. Here, if a specific frequency is the resonant frequency, a magnetic resonance phenomenon occurs between the primary and secondary coils, allowing for more efficient power reception.

[0089] Although not shown in Figure 4, the communication / control unit 220 may also include a communication antenna. The communication antenna can transmit and receive communication signals using communication carriers other than magnetic field communication. For example, the communication antenna can transmit and receive communication signals such as Wi-Fi, Bluetooth, Bluetooth LE, ZigBee, and NFC.

[0090] The communication / control unit 220 transmits and receives information with the wireless power transmitter 100. The communication / control unit 220 may include at least one of either an IB communication module or an OOB communication module.

[0091] An IB communication module can transmit and receive information using magnetic waves with a specific center frequency. For example, the communication / control unit 220 can perform IB communication by transmitting information via a secondary coil by loading it onto a magnetic wave, or by receiving a magnetic wave containing information via a secondary coil. In this case, modulation schemes such as binary phase shift keying (BPSK) or amplitude shift keying (ASK), and coding schemes such as Manchester coding or non-return-to-zerovel (NZR-L) coding can be used to load information onto the magnetic wave or analyze a magnetic wave containing information. Using such IB communication, the communication / control unit 220 can transmit and receive information over distances of several meters at a data transmission rate of several kbps.

[0092] The OOB module can also perform out-of-band communication via a communication antenna. For example, the communication / control unit 220 can be provided as a short-range communication module.

[0093] Examples of short-range communication modules include Wi-Fi, Bluetooth, Bluetooth LE, ZigBee, and NFC.

[0094] The communication / control unit 220 can control the overall operation of the wireless power receiver 200. The communication / control unit 220 can perform calculations and processing of various types of information and control each component of the wireless power receiver 200.

[0095] The communication / control unit 220 can be implemented in a computer or similar device using hardware, software, or a combination thereof. In hardware terms, the communication / control unit 220 can be provided in the form of an electronic circuit that processes electrical signals to perform control functions, and in software terms, it can be provided in the form of a program that drives the hardware communication / control unit 220.

[0096] The load 455 could be a battery. The battery can store energy using the power output from the power pickup unit 210. On the other hand, the mobile device 450 does not necessarily have to include a battery. For example, the battery can be provided in the form of a removable external configuration. In another example, the wireless power receiver 200 may include a drive means that drives various operations of the electronic device instead of a battery.

[0097] Although the mobile device 450 is shown to include a wireless power receiver 200 and the base station 400 is shown to include a wireless power transmitter 100, in a broader sense, the wireless power receiver 200 can be considered identical to the mobile device 450, and the wireless power transmitter 100 can be considered identical to the base station 400.

[0098] Hereinafter, a coil or coil section may also be referred to as a coil assembly, coil cell, or cell, including the coil and at least one element adjacent to the coil.

[0099] Figure 5 is a state transition diagram illustrating the wireless power transmission procedure.

[0100] As shown in Figure 5, the transmission of power from a wireless power transmitter to a receiver according to one embodiment of the present invention is broadly divided into a selection phase 510, a ping phase 520, an identification and configuration phase 530, a negotiation phase 540, a calibration phase 550, a power transfer phase 560, and a renegotiation phase 570.

[0101] The selection phase 510 may be a phase to which the device transitions if a specific error or event is detected while starting or maintaining power transmission—for example, including drawing reference numerals S502, S504, S508, S510, and S512. Here, the specific errors and specific events will be clarified by the following description. In the selection phase 510, the wireless power transmitter may also monitor whether or not an object is present on the interface surface. If the wireless power transmitter detects that an object is present on the interface surface, it may transition to the ping phase 520. In the selection phase 510, the wireless power transmitter may transmit a very short pulse analog ping signal and detect whether or not an object is present in the active area of ​​the interface surface based on the current change in the transmitting coil or primary coil.

[0102] If an object is detected in the selection phase 510, the wireless power transmitter can measure the quality factor of the wireless power resonant circuit (e.g., a power transmitting coil and / or a resonant capacitor). In one embodiment of the present invention, if an object is detected in the selection phase 510, the quality factor can be measured to determine whether the wireless power receiver is placed in the charging area with a foreign object. The coil provided in the wireless power transmitter may experience a decrease in inductance and / or series resistance component within the coil due to environmental changes, which will result in a decrease in the quality factor value. To determine whether a foreign object is present using the measured quality factor value, the wireless power transmitter can receive a reference quality factor value from the wireless power receiver that has been measured in advance when no foreign object is placed in the charging area. In the negotiation phase S540, the reference quality factor value received and the measured quality factor value can be compared to determine whether a foreign object is present. However, in the case of wireless power receivers with low baseline quality factor values—for example, certain wireless power receivers may have low baseline quality factor values ​​depending on their type, application, and characteristics—a problem arises where the difference between the quality factor value measured when foreign matter is present and the baseline quality factor value is not large, making it difficult to determine whether or not foreign matter is present. Therefore, other judgment factors must be considered further, or other methods must be used to determine whether or not foreign matter is present.

[0103] In another embodiment of the present invention, when an object is detected in the selection phase 510, a quality factor value within a specific frequency range (e.g., the operating frequency range) can be measured to determine whether the wireless power receiver is located in the charging area together with the foreign object. The coil of the wireless power transmitter may experience a decrease in inductance and / or series resistance component within the coil due to environmental changes, thereby changing (shifting) the resonant frequency of the coil of the wireless power transmitter. That is, the quality factor peak frequency, which is the frequency at which the maximum quality factor value within the operating frequency band is measured, may be shifted.

[0104] In phase 520, when an object is detected, the wireless power transmitter wakes up the receiver and sends a digital ping to identify whether the detected object is the wireless power receiver. In the ping phase 520, if the wireless power transmitter does not receive a response signal to the digital ping—for example, a signal strength packet—from the receiver, it transitions back to the selection phase 510. Alternatively, in the ping phase 520, the wireless power transmitter may also transition to the selection phase 510 if it receives a signal from the receiver indicating that power transmission is complete—i.e., a charge complete packet.

[0105] Once the ping phase 520 is complete, the wireless power transmitter transitions to the identification and configuration phase 530, in which it identifies the receiver and collects the receiver's configuration and status information.

[0106] In the identification and configuration phase 530, the wireless power transmitter may transition to the selection phase 510 if an unexpected packet is received, if a desired packet has not been received for a predetermined period of time (time out), if there is a packet transmission error, or if no power transfer contract is established.

[0107] The wireless power transmitter can determine whether it is necessary to enter the negotiation phase 540 based on the negotiation field value of the configuration packet received in the identification and configuration phase 530. If the determination indicates that negotiation is necessary, the wireless power transmitter can enter the negotiation phase 540 and perform a predetermined FOD detection procedure. Conversely, if the determination indicates that negotiation is not necessary, the wireless power transmitter can immediately enter the power transmission phase 560.

[0108] In negotiation phase 540, the wireless power transmitter can receive a Foreign Object Detection (FOD) status packet containing a reference quality factor value, or a Foreign Object Detection (FOD) status packet containing a reference peak frequency value, or a status packet containing both a reference quality factor value and a reference peak frequency value. At this time, the wireless power transmitter can determine a quality coefficient threshold for FO detection based on the reference quality factor value, or a peak frequency threshold for FO detection based on the reference peak frequency value.

[0109] The wireless power transmitter can detect whether or not a fault (FO) is present in the charging area using a determined quality factor threshold for FO detection and the currently measured quality factor value (quality factor value measured before the ping phase), and can control power transmission according to the FO detection result. For example, if a FO is detected, power transmission may be interrupted, but this is not limited to that.

[0110] The wireless power transmitter can detect whether or not a FO (Fault Occurrence) is present in the charging region using a determined peak frequency threshold for FO detection and the currently measured peak frequency value (the peak frequency value measured before the ping phase), and can control power transmission according to the FO detection result. For example, if FO is detected, power transmission may be interrupted, but this is not limited to that.

[0111] If an FO is detected, the wireless power transmitter can return to the selection phase 510. Conversely, if no FO is detected, the wireless power transmitter can proceed through the correction phase 550 to the power transmission phase 560. Specifically, if no FO is detected, the wireless power transmitter can determine the power intensity received at the receiving end in the correction phase 550 and measure the power loss at both the receiving and transmitting ends to determine the power intensity transmitted at the transmitting end. That is, the wireless power transmitter can predict the power loss in the correction phase 550 based on the difference between the transmitted power at the transmitting end and the received power at the receiving end. In one embodiment, the wireless power transmitter can also correct the threshold for FOD detection to reflect the predicted power loss.

[0112] During the power transmission phase 560, the wireless power transmitter may transition to the selection phase 510 if an unexpected packet is received, if a desired packet is not received for a predetermined period of time (time out), if a power transfer contract violation occurs, or if charging is complete.

[0113] Furthermore, in the power transmission phase 560, if the wireless power transmitter needs to reconfigure the power transmission contract due to a change in the state of the wireless power transmitter, it can transition to the renegotiation phase 570. At this point, if the renegotiation is successfully completed, the wireless power transmitter can return to the power transmission phase 560.

[0114] The aforementioned power transmission contract can be set based on the status and characteristic information of the wireless power transmitter and receiver. For example, the status information of the wireless power transmitter may include information on the maximum amount of power that can be transmitted and the maximum number of receivers that can be accommodated, while the status information of the receiver may include information on the power requested.

[0115] Figure 6 shows a power control method according to one embodiment.

[0116] In Figure 6, during the power transmission phase 560, the wireless power transmitter 100 and the wireless power receiver 200 can control the amount of power transmitted by communicating in parallel with power transmission and reception. The wireless power transmitter and wireless power receiver operate at specific control points. The control points indicate the combination of voltage and current provided at the output terminal of the wireless power receiver when power transmission occurs.

[0117] More specifically, the wireless power receiver selects a desired control point—such as the desired output current / voltage and the temperature at a specific location on the mobile device—and also determines the actual control point currently in operation. Using the desired and actual control points, the wireless power receiver can calculate a control error value and transmit it to the wireless power transmitter as a control error packet.

[0118] The wireless power transmitter can then use the received control error packets to set / control new operating points—amplitude, frequency, and duty cycle—and control power transfer. Thus, control error packets are transmitted / received at regular time intervals during the power transfer phase, and in one embodiment, the wireless power receiver can set the control error value to a negative number if it wants to reduce the current of the wireless power transmitter, or to a positive number if it wants to increase the current. In this way, in induction mode, power transfer can be controlled by the wireless power receiver transmitting control error packets to the wireless power transmitter.

[0119] The resonant mode described below can operate in a different manner than the inductive mode. In resonant mode, one wireless power transmitter must be able to serve multiple wireless power receivers simultaneously. However, when controlling power transmission as in the inductive mode described above, the transmitted power is controlled by communication with one wireless power receiver, so controlling power transmission to additional wireless power receivers may be difficult. Therefore, in the resonant mode of the present invention, the wireless power transmitter attempts to transmit basic power in common, and the amount of power received by the wireless power receiver controls its own resonant frequency. However, even in such operation of resonant mode, the method described in Figure 6 is not completely excluded, and additional transmission power can also be controlled using the method in Figure 6.

[0120] Figure 7 is a block diagram of a wireless power transmission device according to another embodiment. This can belong to a magnetic resonance or shared mode wireless power transmission system. Shared mode refers to a mode in which one-to-many communication and charging occur between a wireless power transmission device and a wireless power reception device. Shared mode is implemented using either magnetic induction or resonance.

[0121] As shown in Figure 7, the wireless power transmitter 700 may include at least one of the following: a cover 720 covering a coil assembly, a power adapter 730 supplying power to a power transmitting unit 740, a power transmitter 740 transmitting wireless power, or a user interface 750 providing power transmission progress and other related information. In particular, the user interface 750 may be included optionally or as another user interface 750 of the wireless power transmitter 700.

[0122] The power transmitter 740 may include at least one of the following: a coil assembly 760, an impedance matching circuit 770, an inverter 780, a communication unit 790, or a control unit 710.

[0123] The coil assembly 760 includes at least one primary coil that generates a magnetic field and can also be called a coil cell.

[0124] The impedance matching circuit 770 can provide impedance matching between the inverter and the primary coil(s). The impedance matching circuit 770 can generate resonance at a frequency suitable for boosting the primary coil current. In the multi-coil power transmitter 740, the impedance matching circuit may also additionally include a multiflex for routing signals from the inverter to a subset of the primary coils. The impedance matching circuit may also be called a "tank circuit".

[0125] The impedance matching circuit 770 may include a capacitor, an inductor, and a switching element for switching their connections. Impedance matching can be performed by detecting the reflected waves of the radio power transmitted through the coil assembly 760 and switching the switching element based on the detected reflected waves to adjust the connection state of the capacitor and inductor, or by adjusting the capacitance of the capacitor or the inductance of the inductor. In some cases, the impedance matching circuit 770 may be omitted, and this specification also includes embodiments of the radio power transmitter 700 in which the impedance matching circuit 770 is omitted.

[0126] The inverter 780 can convert a DC input to an AC signal. The inverter 780 can be driven in a half-bridge or full-bridge configuration to generate adjustable frequency pulse waves and duty cycles. The inverter may also include multiple stages to adjust the input voltage level.

[0127] The communication unit 790 can communicate with the power receiver. The power receiver performs load modulation to communicate requests and information to the power transmitter. Thus, the power transmitter 740 can use the communication unit 790 to monitor the amplitude and / or phase of the primary coil current and / or voltage in order to demodulate the data transmitted by the power receiver.

[0128] Furthermore, the power transmitter 740 can also control its output power to transmit data via the communication unit 790 using methods such as FSK (Frequency Shift Keying).

[0129] The control unit 710 can control the communication and power transmission of the power transmitter 740. The control unit 710 can control power transmission by adjusting the aforementioned operating points. The operating points can be determined by, for example, at least one of the operating frequency, duty cycle, and input voltage.

[0130] The communication unit 790 and the control unit 710 may be provided as separate units / elements / chipsets, or they may be provided as a single unit / element / chipset.

[0131] Figure 8 shows a wireless power receiving device according to another embodiment. This belongs to a magnetic resonance or shared mode wireless power transmission system.

[0132] In Figure 8, the wireless power receiving device 800 may include at least one of the following: a user interface 820 that provides power transmission progress and other related information; a power receiving unit 830 that receives wireless power; a load circuit 840; or a base 850 that supports and covers a coil assembly. In particular, the user interface 820 may be included optionally or as another user interface 82 of the power receiving equipment.

[0133] The power receiver 830 may include at least one of the following: a power converter 860, an impedance matching circuit 870, a coil assembly 880, a communication unit 890, or a control unit 810.

[0134] The power converter 860 can convert the AC power received from the secondary coil into a voltage and current suitable for the load circuit. In one embodiment, the power converter 860 includes a rectifier. The rectifier can rectify the received radio power, converting it from AC to DC. The rectifier can convert AC to DC using diodes or transistors and smooth it using capacitors and resistors. As rectifiers, full-wave rectifiers, half-wave rectifiers, voltage multipliers, etc., implemented in bridge circuits, can be used. Furthermore, the power converter can also adapt the reflected impedance of the power receiver.

[0135] The impedance matching circuit 870 can provide impedance matching between the power converter 860 and load circuit 870 and the secondary coil. In embodiments, the impedance matching circuit can generate a resonance near 100 kHz, which can enhance power transmission. The impedance matching circuit 870 can consist of a capacitor, an inductor, and switching elements that switch a combination thereof. Impedance matching can be achieved by controlling the switching elements of the circuits constituting the impedance matching circuit 870 based on the voltage, current, power, and frequency values ​​of the received radio power. In some cases, the impedance matching circuit 870 may be omitted, and this specification also includes embodiments of the radio power receiver 200 in which the impedance matching circuit 870 is omitted.

[0136] The coil assembly 880 includes at least one secondary coil and optionally may further include an element that shields the metal parts of the receiver from the magnetic field.

[0137] The communication unit 890 can perform load modulation to communicate requests and other information to the power transmitter.

[0138] For this purpose, the power receiver 830 can also switch a resistor or capacitor to change the reflection impedance.

[0139] The control unit 810 can control the received power. To this end, the control unit 810 can determine / calculate the difference between the actual operating point and the desired operating point of the power receiver 830. The control unit 810 then adjusts / reduces the difference between the actual operating point and the desired operating point by adjusting the reflection impedance of the power transmitter and / or requesting an adjustment of the operating point of the power transmitter. By minimizing this difference, optimal power reception can be achieved.

[0140] The communication unit 890 and the control unit 810 may be provided as separate components / chipsets or as a single component / chipset.

[0141] Figure 9 shows a communication frame structure according to one embodiment. This could be a communication frame structure in shared mode.

[0142] As shown in Figure 9, in shared mode, different types of frames can be used together. For example, in shared mode, a slotted frame having multiple slots, such as (A), and a free-format frame without a specific form, such as (B), can be used. More specifically, a slotted frame is a frame for transmitting short data packets from the wireless power receiver 200 to the wireless power transmitter 100, while a free-format frame, since it does not have multiple slots, may be a frame capable of transmitting long data packets.

[0143] On the other hand, slot frames and free-format frames can be renamed in various ways by those skilled in the art. For example, slot frames can be renamed channel frames, and free-format frames can be renamed message frames, etc.

[0144] More specifically, the slot frame may include a sink pattern indicating the start of a slot, a measurement slot, nine slots, and additional sink patterns having the same time interval before each of the nine slots.

[0145] Here, the additional sink pattern is a different sink pattern from the sink pattern indicating the start of the frame described above. More specifically, the additional sink pattern may indicate information about adjacent slots (i.e., two consecutive slots located on either side of the sink pattern) rather than indicating the start of a frame.

[0146] A sink pattern can be positioned between any two consecutive slots among the nine slots. In this case, the sink pattern provides information about the two consecutive slots.

[0147] Furthermore, the nine slots and the sink patterns provided in front of each of the nine slots may each have the same time interval. For example, the nine slots may have a time interval of 50 ms. The nine sink patterns may also have a time length of 50 ms.

[0148] On the other hand, a free-format frame like (B) may not have any specific form other than a sink pattern and measurement slots indicating the start of the frame. That is, the free-format frame may serve a different role from the slot frame, for example, to communicate long data packets (e.g., additional owner information packets) between the wireless power transmitter and the wireless power receiver, or to select one of several coils in a wireless power transmitter composed of multiple coils.

[0149] Below, we will explain the sync patterns included in each frame in more detail, along with diagrams.

[0150] Figure 10 shows the structure of a sink pattern according to one embodiment.

[0151] As shown in Figure 10, the sink pattern consists of a preamble, a start bit, a response field, a type field, an info field, and a parity bit. In Figure 10, the start bit is shown as ZERO.

[0152] More specifically, the preamble consists of consecutive bits that can all be set to 0. In other words, the preamble is a set of bits used to match the time length of the sync pattern.

[0153] The number of bits that make up the preamble can depend on the operating frequency, such that the length of the sink pattern is as close to 50ms as possible, but not exceeding 50ms. For example, if the operating frequency is 100kHz, the sink pattern consists of 2 preamble bits, and if the operating frequency is 105kHz, the sink pattern consists of 3 preamble bits.

[0154] The start bit is the bit that follows the preamble and means zero. The zero may be a bit indicating the type of sync pattern. Here, the types of sync patterns include frame syncs, which contain information about frames, and slot syncs, which contain information about slots. That is, the sync pattern may be a frame sync located between consecutive frames and indicating the start of a frame, or a slot sync located between consecutive slots among a plurality of slots that make up a frame and containing information about those consecutive slots.

[0155] For example, if the zero is 0, it means that the slot is a slot sink located between slots, and if it is 1, it means that the sink pattern is a frame sink located between frames.

[0156] The parity bit is the last bit of the sink pattern and indicates the number of bits that make up the data fields of the sink pattern (i.e., the response field, type field, and information field). For example, the parity bit can be 1 if the number of bits that make up the data fields of the sink pattern is even, and 0 otherwise (i.e., odd).

[0157] The Response field may contain response information from the radio power transmitter to communication with a radio power receiver within a slot prior to the sink pattern. For example, the Response field may have "00" if no communication with the radio power receiver is detected. Alternatively, the Response field may have "01" if a communication error is detected in the communication with the radio power receiver. A communication error may occur when two or more radio power receivers attempt to approach a single slot, resulting in a collision between the two or more radio power receivers.

[0158] Furthermore, the response field may include information indicating whether or not the data packet has been accurately received from the wireless power receiver. More specifically, the response field may be "10" (10-not acknowledge, NAK) if the wireless power transmitter denies the data packet, and "11" (11-acknowledge, ACK) if the wireless power transmitter confirms the data packet.

[0159] The type field indicates the type of sink pattern. More specifically, the type field may have a "1" indicating that it is a frame sink if the sink pattern is the first sink pattern of the frame (i.e., the pattern of the first sink of the frame and located prior to the measurement slot).

[0160] Additionally, the type field may have a value of "0" in a slot frame, indicating that it is a slot sink if the sink pattern is not the first sink pattern of the frame.

[0161] Furthermore, the meaning of the information field's value is determined by the type of sink pattern indicated by the type field. For example, if the type field is 1 (i.e., indicating frame sinking), the meaning of the information field can indicate the type of frame. That is, the information field indicates whether the current frame is a slotted frame or a free-format frame. For example, if the information field is "00", it indicates a slotted frame, and if the information field is "01", it indicates a free-format frame.

[0162] In contrast, if the type field is 0 (i.e., a slot sink), the information field can indicate the state of the next slot located after the sink pattern. More specifically, the information field may have "00" if the next slot is allocated to a specific radio power receiver, "01" if the slot is locked for temporary use by the specific radio power receiver, or "10" if the slot is freely available to any radio power receiver.

[0163] Figure 11 shows the operating state of a wireless power transmitter and a wireless power receiver in shared mode according to one embodiment.

[0164] As shown in Figure 11, a wireless power receiver operating in shared mode can operate in any one of the following states: Selection Phase 1100, Introduction Phase 1110, Configuration Phase 1120, Negotiation Phase 1130, and Power Transfer Phase 1140.

[0165] First, a wireless power transmitter according to one embodiment can transmit a wireless power signal in order to detect a wireless power receiver. In other words, the process of detecting a wireless power receiver using a wireless power signal can be called analog ping.

[0166] On the other hand, the wireless power receiving device that has received the wireless power signal can enter the selection phase 1100. As described above, the wireless power receiving device that has entered the selection phase 1100 can detect the presence of the FSK signal on the wireless power signal.

[0167] In other words, the wireless power receiver can communicate in either exclusive mode or shared mode, depending on the presence or absence of the FSK signal.

[0168] More specifically, a radio power receiver can operate in shared mode if the radio power signal includes an FSK signal, and in exclusive mode otherwise.

[0169] When the wireless power receiver operates in shared mode, the wireless power receiver can enter the deployment phase 1110. In the deployment phase 1110, the wireless power receiver can send control information (CI) packets to the wireless power transmitter in order to transmit control information packets during the setup phase, negotiation phase, and power transmission phase. The control information packet may have a header and information related to control. For example, the header of the control information packet may be 0X53.

[0170] In deployment phase 1110, the wireless power receiver attempts to request a free slot to transmit control information (CI) packets across the following configuration, negotiation, and power transmission phases. At this point, the wireless power receiver selects a free slot and transmits the first CI packet. If the wireless power transmitter responds to the CI packet with an ACK, the wireless power transmitter enters the configuration phase. If the wireless power transmitter responds with a NACK, it indicates that another wireless power receiver is proceeding through the configuration and negotiation phases. In this case, the wireless power receiver attempts to request a free slot again.

[0171] If the radio power receiver receives an ACK in response to a CI packet, it determines the position of the private slot in the frame by counting the remaining slot sinks up to the first frame sink. For all subsequent slot-based frames, the radio power receiver transmits a CI packet through that slot.

[0172] If the wireless power transmitter allows the wireless power receiver to proceed to the configuration phase, the wireless power transmitter provides a series of locked slots for the exclusive use of the wireless power receiver. This ensures that the wireless power receiver proceeds to the configuration phase without conflict.

[0173] The radio power receiver transmits a sequence of data packets, such as two identification data packets (IDHI and IDLO), using a lock slot. Upon completion of this phase, the radio power receiver enters the negotiation phase. During the negotiation phase, the radio power transmitter continues to provide the radio power receiver with a lock slot for exclusive use. This ensures that the radio power receiver can proceed through the negotiation phase without collisions.

[0174] The wireless power receiver uses the lock slot to transmit one or more negotiation data packets, which may be mixed with proprietary data packets. Ultimately, this sequence ends with a specific request (SRQ) packet. Upon completion of this sequence, the wireless power receiver enters the power transmission phase, and the wireless power transmitter ceases providing the lock slot.

[0175] In power transmission mode, the wireless power receiver transmits CI packets using its assigned slot and receives power. The wireless power receiver may include a regulator circuit. The regulator circuit may be included in the communication / control unit. The wireless power receiver can self-regulate its reflected impedance via the regulator circuit. In other words, the wireless power receiver can adjust the impedance it reflects to transmit the amount of power required by the external load. This can prevent excessive power reception and overheating.

[0176] In shared mode, the wireless power transmitter may not adjust the power in response to the received CI packet (depending on the operating mode), so in this case, control is required to prevent overvoltage conditions.

[0177] The following disclosure concerns authentication between wireless power transmitters and wireless power receivers. Wireless power transmitters and wireless power receivers are only mutually compatible and capable of proper power transmission if they are implemented using pre-defined, identical power transmission and communication interfaces. Even if the wireless power transmitter and receiver are not manufactured by the same company, they are mutually compatible if they are manufactured according to the same technical standards or specifications. However, even when adhering to the same technical standards, the quality achieved varies from manufacturer to manufacturer, and failure to faithfully and accurately adhere to the standards can lead to problems with wireless charging. In particular, products with problems with foreign object detection (FOD) and overheating prevention functions pose a risk of safety accidents such as explosions. Therefore, standardization bodies that manage technical standards offer a service to certify genuine products by testing whether each manufacturer's wireless power transmitter or receiver accurately conforms to the standard technology (compliance) and whether equipment interoperability is maintained, through accredited certification bodies.

[0178] Nevertheless, since it is practically difficult to completely prevent uncertified products from circulating in the market, it is necessary to ensure stability and reliability by mutually authenticating wireless power transmitters and receivers that have already entered the market, verifying that they are functioning correctly before and after wireless charging. In other words, if we call the process of an accredited certification body granting genuine product certification before the product's release a pre-certification procedure, then the process of performing authentication between products during the wireless charging operation after the product's release is called a post-certification procedure. For example, mutual authentication between products can be performed via an in-band communication channel and is compatible with USB-C certification. If authentication fails, the wireless power receiver can warn the user and either charge in low power mode or remove the power signal.

[0179] While this specification uses the WPC's Qi standard as an example of a standard technology, the technical concept of the present invention includes not only the Qi standard but also embodiments of certification based on other standards.

[0180] When introducing USB-C certification to wireless power transmission systems using in-band communication, the performance metrics shown in the following table are derived. In other words, USB-C becomes a model for wireless charging certification.

[0181] [Table 3]

[0182] In Table 3, PRx refers to a wireless power receiver and PTx refers to a wireless power transmitter. Certification includes certification of a wireless power transmitter by a wireless power receiver and certification of a wireless power receiver by a wireless power transmitter.

[0183] Authenticating a wireless power transmitter using full authentication can take up to approximately 3 minutes, due to the large size of USB-C certificates and the low bit rate communication protocol employed by wireless power transmission systems. This frequent full authentication can be particularly inconvenient for users in public venues where users frequently change wireless charging spots. Therefore, the size of the authentication chain or packets needs to be defined compactly or simply. Ideally, the 128-bit security level (ECDSA with SHA256) for USB-C authentication should be maintained while reducing the full authentication time to a reasonable duration (within 60 seconds). Of course, the time required for authentication may increase due to repeated data transmissions caused by traffic errors.

[0184] The following discloses specific embodiments of certificates, authentication procedures, authentication messages, and lower-level communication protocols used for authentication of standard technologies. All authentication-related communications, protocols, messages, packets, etc., described below can be generated, processed, stored, transmitted, and modified by the communication and control units 120, 220, and communication units 790, 890 described in this specification.

[0185] 1. Wireless Charging Certification

[0186] In terms of certificate chain levels, the level of a certificate chain can be limited. For example, a certificate chain may have three levels. Even with a minimum chain level, manufacturers can still issue their own certificates for their products, and the burden on both manufacturers and certificate authorities (CAs) can be reduced. A certificate chain is a series of two or more certificates, where each certificate is signed by a preceding certificate within the chain.

[0187] In terms of certificate types, it can be specified that two types of certificates are transmitted between a wireless power transmitter and a receiver. Here, the two types of certificates may include an intermediate certificate and a leaf certificate. The root certificate is identical between the two devices that support mutual authentication. The root certificate is self-signed and is the first certificate in the certificate chain. The leaf certificate is the last certificate in the certificate chain, and the intermediate certificate is a certificate in the certificate chain that is neither a root certificate nor a leaf certificate.

[0188] In terms of certificate formatting, the certificate format may be specified as a reduced or simplified format. Here, "reduced" or "simplified" format can mean a format that is reduced or simplified for wireless charging compared to the USB-C certificate format (X509v3 format). For example, a simplified certificate format for intermediate and leaf certificates may be less than 100 bytes (e.g., 80 bytes). In this case, the root certificate may still follow the USB-C certificate format. Hereafter, the simplified certificate format may be referred to as the wireless charging certificate format or Qi certificate format. For wireless power transmission systems that support out-of-band (OOB) communication, such as PC1, it goes without saying that a wireless charging certificate in USB-C format can be provided because a wider bandwidth can be used.

[0189] Figure 12 is a block diagram showing a wireless charging certificate format according to one embodiment.

[0190] As shown in Figure 12, the wireless charging certificate format includes certificate type, certificate length, identification information (ID), reserved bits, public key, and signature.

[0191] The certificate type can be, for example, 1 byte and can indicate that the certificate is one of the following: a root certificate, an intermediate certificate, or a leaf certificate; it can indicate that it is a certificate relating to a wireless power transmitter or a wireless power receiver; or it can indicate both. For example, if the bit sequence b3-b0 of the certificate type is '0000'b, it indicates an intermediate certificate, and if it is '0001'b, it indicates a leaf certificate. Similarly, if the bit sequence b7-b4 of the certificate type is '0001'b, it indicates a certificate relating to a wireless power transmitter, and if it is '0000'b, it indicates a certificate relating to a wireless power receiver. Therefore, when the bit sequence of the certificate type reaches a certain value, it can be determined that the certificate relates to a wireless power transmitter and is a leaf certificate.

[0192] The length of a certificate is, for example, 2 bytes, and the length of the certificate can be indicated in bytes.

[0193] The identification information may be, for example, 6 bytes and may indicate the manufacturer's code of the wireless power transmitter or the wireless power receiver, or it may indicate the WPID (wireless power ID).

[0194] The spare bits may be, for example, 7 bytes. The public key may be, for example, 32 bytes. The signature may be, for example, 32 or 64 bytes.

[0195] When authentication is performed via in-band communication based on the wireless charging certificate format shown in Figure 12, full mutual authentication can be completed in less than one minute, as shown in Table 4.

[0196] [Table 4]

[0197] Figure 12 illustrates a case where the certificate format size is 80 bytes, but this is merely an example, and embodiments in which each field is defined with a different number of bits are also obvious to those skilled in the art and fall under the technical concept of the present invention.

[0198] Figure 13A is a block diagram showing a wireless charging certificate format according to another embodiment.

[0199] As shown in Figure 13A, the wireless charging certificate format includes the certificate type, PTx and Leaf indicators, certificate length, identification information (ID), reserved bits, public key, and signature.

[0200] In the wireless charging certificate format shown in Figure 13A, the PTx and Leaf indicators are separated from the certificate type and assigned to different bits within the same byte (B0) as the certificate type.

[0201] The certificate type can be, for example, 6 bits, and may indicate that the certificate is one of the following: a root certificate, an intermediate certificate, or a leaf certificate; it may indicate that it is a certificate relating to a wireless power transmitter or a wireless power receiver; or it may indicate both.

[0202] The PTx and Leaf indicators indicate whether the certificate in question pertains to a wireless power transmitter and whether it is a Leaf certificate. In other words, the PTx and Leaf indicators can indicate whether the certificate in question is a Leaf certificate pertaining to a wireless power transmitter.

[0203] The PTx and leaf indicators are configured, for example, as 2 bits, including a 1-bit PTx indicator and a 1-bit leaf indicator. In this case, the PTx indicator shows 1 if the certificate pertains to a wireless power transmitter and 0 if it pertains to a wireless power receiver. The leaf indicator is 1 bit, and its value can be set to 1 if the certificate pertains to a leaf, and to 0 if it does not pertain to a leaf. Figure 13A shows that each bit is set to 1, indicating that the certificate is a PTx leaf certificate.

[0204] The PTx and leaf indicators are contained within the same byte (B0) as the certificate type, are configured in the bit sequence immediately adjacent to the certificate type, and are assigned to bits different from those of the certificate type.

[0205] The certificate length can be, for example, 1 byte, and the length of the certificate can be indicated in bytes.

[0206] The identification information may be, for example, 6 bytes and may indicate the manufacturer code of the wireless power transmitter or wireless power receiver (PRx manufacturer code: PRMC), or it may indicate the WPID (wireless power ID). Alternatively, if the certificate type is an intermediate certificate, the identification information may indicate the manufacturer code of the wireless power transmitter or wireless power receiver, and if the certificate type is a leaf certificate, the identification information may indicate the WPID.

[0207] The spare bits could be, for example, 4 bytes. The public key could be, for example, 32 bytes. The signature could be, for example, 64 bytes.

[0208] As shown in Figure 13A, when authentication is performed via in-band communication based on the same wireless charging certificate format, full mutual authentication can be completed within 60 seconds, as shown in Table 5.

[0209] [Table 5]

[0210] Figure 13A illustrates a case where the certificate format size is 108 bytes, but this is merely an example, and embodiments in which each field is defined with a different number of bits are also obvious to those skilled in the art and fall under the technical concept of the present invention.

[0211] As a commercial performance requirement, the authentication procedure preferably completes the authentication of the responder's initiator within 60 seconds in an environment using in-band communication. Furthermore, the authentication procedure preferably provides a mechanism for secure recognition of a previously authenticated responder within 20 seconds in an environment using in-band communication.

[0212] Figure 13B is a block diagram showing a wireless charging certificate format according to another embodiment.

[0213] As shown in Figure 13B, the wireless charging certificate format includes the Qi Authentication Certificate Structure Version, spare bits, PTx and leaf indicators, certificate type, signature offset, serial number, issuer ID, subject ID, public key, and signature.

[0214] Within the wireless charging certificate format, the PTx and Leaf indicators are separated from the certificate type and assigned to different bits within the same byte (B0) as the certificate type.

[0215] The PTx and Leaf indicators indicate whether the certificate in question pertains to a wireless power transmitter, as well as whether it is a Leaf certificate. In other words, the PTx and Leaf indicators can indicate whether the certificate in question is a Leaf certificate pertaining to a wireless power transmitter.

[0216] Unlike in Figure 13A, the PTx and Leaf indicators can be 1 bit each. If the PTx and Leaf indicators are 0, this can indicate that the certificate is either not a Leaf certificate or is a Leaf certificate for a wireless power receiver. Conversely, if the PTx and Leaf indicators are 1, this can indicate that the certificate is a Leaf certificate for a wireless power transmitter.

[0217] The certificate type can be, for example, 2 bits, which can indicate that the certificate is one of the following: a root certificate, an intermediate certificate, or a leaf certificate, or it can indicate all of these.

[0218] 2. Instructions regarding support for authentication functions

[0219] If either the wireless power transmitter or wireless power receiver does not support the authentication function (for example, legacy products already on the market may not support the new authentication function), then the authentication procedure cannot be performed between them. In other words, for the authentication procedure to be performed, both the wireless power transmitter and wireless power receiver must support the authentication function. Furthermore, since the authentication function may or may not be supported by the manufacturer depending on the product version, a procedure for confirming this and the messages used in this procedure are required. Moreover, if only one of the wireless power transmitters or receivers supports the authentication function and the other is a legacy product, backward compatibility for minimum charging functionality must be satisfied. Even for devices that do not support authentication due to system policy, 5W (or a minimum power below that, e.g., 3W) must be supported.

[0220] The wireless power transmitter can use a capability packet to inform the wireless power receiver whether or not it supports the authentication function (in the case of authentication of the wireless power transmitter by the wireless power receiver). On the other hand, the wireless power receiver can use a configuration packet to inform the wireless power transmitter whether or not it supports the authentication function (in the case of authentication of the wireless power receiver by the wireless power transmitter). The structure of the instruction information (capability packet and configuration packet) regarding whether or not the authentication function is supported will be disclosed in more detail below.

[0221] Figure 14 shows the structure of a performance packet for a wireless power transmission device according to one embodiment.

[0222] As shown in Figure 14, a performance packet with a corresponding header value of 0X31 is 3 bytes long, with the first byte (B0) containing the power class and guaranteed power value, the second byte (B1) containing the reserved and potential power value, and the third byte (B2) containing the reserved, Auth, NFCPP, NFCD, WPID, and Not REs Sens. Specifically, the Auth bit is 1 bit, and for example, a value of 0 indicates that the wireless power transmitter does not support the authentication function, while a value of 1 indicates that the wireless power transmitter supports the authentication function.

[0223] Figure 15 shows the structure of a performance packet for a wireless power transmitter according to another embodiment.

[0224] As shown in Figure 15, a performance packet with a corresponding header value of 0X31 consists of 3 bytes: the first byte (B0) contains the power class and guaranteed power value; the second byte (B1) contains the reserved and potential power value; and the third byte (B2) contains the Authentication Initiator (AI), Authentication Responder (AR), reserved, WPID, and Not REs Sens. Specifically, the Authentication Initiator is a single bit; for example, if its value is '1b', it indicates that the wireless power transmitter can operate as an Authentication Initiator. Similarly, the Authentication Responder is a single bit; for example, if its value is '1b', it indicates that the wireless power transmitter can operate as an Authentication Responder.

[0225] Figure 16 shows the structure of a configuration packet for a wireless power receiving device according to one embodiment.

[0226] As shown in Figure 16, a configuration packet with a corresponding header value of 0X51 is 5 bytes long, with the first byte (B0) containing the power class and maximum power value, the second byte (B1) containing reserved, the third byte (B2) containing Prop, reserved, ZERO, and Count, the fourth byte (B3) containing the window size and window offset, and the fifth byte (B4) containing Neg, polarity, depth, Auth, and reserved. Specifically, Auth is 1 bit, and for example, a value of 0 indicates that the wireless power receiver does not support the authentication function, while a value of 1 indicates that the wireless power receiver supports the authentication function.

[0227] Figure 17 shows the structure of a configuration packet for a wireless power receiving device according to another embodiment.

[0228] As shown in Figure 17, a configuration packet with a corresponding header value of 0X51 is 5 bytes long, with the first byte (B0) containing the power class and maximum power value, the second byte (B1) containing AI, AR, and Reserve, the third byte (B2) containing Prop, Reserve, ZERO, and Count, the fourth byte (B3) containing the window size and window offset, and the fifth byte (B4) containing Neg, polarity, depth, Auth, and Reserve. Specifically, the Authentication Initiator is 1 bit, and for example, if its value is '1'b, it indicates that the wireless power receiver can operate as an Authentication Initiator. Similarly, the Authentication Responder is 1 bit, and for example, if its value is '1b', it indicates that the wireless power receiver can operate as an Authentication Responder.

[0229] 3. Timing between authentication-related procedures and the wireless charging phase

[0230] The procedures for determining whether or not the authentication function is supported, and the authentication procedures, can be carried out over at least one or more of the following phases: the identification and configuration phase, the negotiation phase, the calibration phase, the power transmission phase, the renegotiation phase, and the deployment phase.

[0231] For example, the authentication procedure can be performed during the negotiation phase. However, when performing quick authentication during the negotiation phase, the process of reading and verifying DIGESTS via in-band communication can take approximately 4 seconds. Therefore, from the perspective of user convenience, it may be considered to provide wireless charging at basic power even before authentication, regardless of whether authentication has been performed, rather than starting charging after authentication is complete. This is also preferable from the perspective of reverse compatibility with devices that do not have an authentication function.

[0232] As another example, the authentication procedure can be performed over a negotiation phase and a power transmission phase. During the identification and configuration phases, the packet sequence is strictly controlled and only unidirectional communication from the wireless power receiving device to the transmitting device is allowed, whereas during the negotiation and power transmission phases, bidirectional communication is allowed. Thus, the authentication procedure can be performed during the negotiation and power transmission phases where bidirectional communication is allowed. During the negotiation phase, quick authentication is performed by a wireless power transmitting or receiving device that exchanges {GET_DIGESTS,CHALLENGE} messages. And a power contract can be concluded based on the established trust. When the wireless power transmitting and receiving devices first meet by checking DIGESTS, an initial power contract based on the system policy is established and the power transmission phase is entered to provide default low power to the wireless power receiving device as soon as possible. During the power transmission phase, full authentication is performed by a wireless power transmitting or receiving device that exchanges {GET_CERTIFICATE,CHALLENGE} messages. When the full authentication is successfully completed, the wireless power transmitting device and / or the receiving device updates the power contract.

[0233] As yet another example, the wireless power transmitting and receiving devices can enter the power transmission phase immediately without authentication and then perform the authentication procedure during the power transmission phase. If the authentication is successful during the power transmission phase, the power contract is updated via a re-negotiation phase or the wireless power transmitting device can support the target power or full power at the level desired by the wireless power transmitting / receiving device. Thus, the convenience of the user is increased.

[0234] As another example, in the case of authentication of a wireless power transmitter (PTx) by a wireless power receiver (PRx), the wireless power receiver can perform a procedure in the negotiation phase to confirm whether the wireless power transmitter supports an authentication function. In this case, power transmission may already be in progress based on an initial power contract prior to the negotiation phase. In the negotiation phase, the wireless power receiver can confirm whether the wireless power transmitter supports the authentication function by following the procedure by transmitting a query packet and checking its response. On one side, the query packet can be a general request packet (0x07). In this case, when the wireless power receiver transmits the general request packet to the wireless power transmitter, the wireless power transmitter transmits a performance packet including authentication (auth) as shown in FIG. 14 or FIG. 15 to the wireless power receiver as a response. On the other side, the query packet can be a specific request packet (0x20). In this case, when the wireless power receiver transmits the specific request packet to the wireless power transmitter, the wireless power transmitter responds with ACK (if it supports the authentication function) or NACK (if it does not support the authentication function). When it is confirmed in the negotiation phase that the wireless power transmitter supports the authentication function, the wireless power receiver can establish a power contract of 5 W or more with the wireless power transmitter (PC0).

[0235] The authentication procedure can only be initiated once the wireless power receiver confirms that the wireless power transmitter supports the authentication function. More specifically, the wireless power receiver can perform the authentication procedure with the wireless power transmitter after reaching a stable operation point in which it transmits control error packets (CEPs) at approximately 250ms intervals. During the power transmission phase, the authentication procedure can be used to renew an existing power contract. That is, the wireless power receiver can renegotiate the power contract to increase the power level under the existing power contract as a result of the authentication procedure. In this case, the wireless power receiver can renew the power contract by power management policy by transmitting a renegotiation packet (0x09). For example, if the authentication procedure (with DIGEST) is successful, the wireless power receiver can renew the power contract to the increased power or maintain the current power contract. Conversely, if the authentication procedure fails, the wireless power receiver can renew the power contract to the decreased power or remove the power signal.

[0236] Another example is the authentication of a PRx by a PTx. In this case, the PRx can perform a procedure in the initialization phase to determine whether the PRx supports the authentication function. The initialization phase can be any of the phases prior to the negotiation phase, such as the selection phase, ping phase, or identification and configuration phase. In the initialization phase, the PRx receives a configuration packet from the PRx that includes authentication (auth) as shown in Figure 16 or Figure 17 to determine whether the PRx supports the authentication function.

[0237] Once the wireless power transmitter confirms support for the wireless power receiver's authentication function, the authentication procedure can be initiated during the negotiation phase. At this point, an initial power contract is concluded. More specifically, the wireless power transmitter waits for DIGESTS to be received from the wireless power receiver. If the wireless power transmitter recognizes that the wireless power receiver has already been authenticated previously, the authentication procedure is successful. If the wireless power transmitter fails to recognize the DIGESTS, the wireless power transmitter continues the authentication procedure during the power transmission phase. According to the power management policy, the wireless power transmitter establishes a power contract with the wireless power receiver. At this point, the wireless power transmitter can establish a power contract of 5W or more with the wireless power receiver (PC0) that has passed authentication as DIGESTS. If the authentication procedure is completed during the power transmission phase, the wireless power transmitter can renegotiate the power contract to increase the power level.

[0238] After the wireless power receiver reaches a normal or stable operation point during the power transmission phase, transmitting control error packets (CEP, 0x03) at approximately 250ms intervals, the wireless power transmitter can perform an authentication procedure with the wireless power receiver. During the power transmission phase, the authentication procedure can be used to renew an existing power contract. That is, the wireless power receiver can renegotiate the power contract to increase the power level under the existing contract based on the results of the authentication procedure. In this case, the wireless power receiver can renew the power contract by the power management policy by transmitting a renegotiation packet (0x09). For example, if the authentication procedure (along with DIGEST) is successful, the wireless power receiver can renew the power contract to the increased power or maintain the current power contract. Conversely, if the authentication procedure fails, the wireless power receiver can renew the power contract to the decreased power or remove the power signal.

[0239] 4. Authentication procedure and authentication message

[0240] The authentication procedure and the various messages used in the authentication procedure are disclosed below.

[0241] Messages used in authentication procedures are called authentication messages. Authentication messages are used to carry information related to authentication. There are two types of authentication messages: one is an authentication request, and the other is an authentication response. Authentication requests are sent by the authentication initiator, and authentication responses are sent by the authentication responder. Both the wireless power transmitter and receiver can be either an authentication initiator or an authentication responder. For example, if the wireless power transmitter is the authentication initiator, the wireless power receiver becomes the authentication responder, and if the wireless power receiver is the authentication initiator, the wireless power transmitter becomes the authentication responder.

[0242] Authentication request messages include GET_DIGESTS (e.g., 4 bytes), GET_CERTIFICATE (e.g., 8 bytes), and CHALLENGE (e.g., 36 bytes).

[0243] The authentication response message includes DIGESTS (e.g., 4 + 32 bytes), CERTIFICATE (e.g., 4 + certificate chain (3 × 512 bytes) = 1540 bytes), CHALLENGE_AUTH (e.g., 168 bytes), and ERROR (e.g., 4 bytes).

[0244] Authentication messages can also be called authentication packets, authentication data, or authentication control information. Similarly, messages such as GET_DIGEST and DIGESTS can be called GET_DIGEST packets or DIGEST packets.

[0245] The following describes the procedure by which a wireless power receiver authenticates a wireless power transmitter based on such an authentication message.

[0246] (1) Authentication of PTx by PRx using a wireless power receiving device.

[0247] When authentication of a PTx by PRx by a wireless power receiver operates based on in-band communication, the required time for each stage is as shown in Table 6 or Table 7.

[0248] [Table 6]

[0249] Table 6 shows an example of the request time for each authentication message when the power contract is based on the results of GET_DIGESTS during the negotiation phase. If the wireless power receiver already knows the DIGEST about the wireless power transmitter, the GET_CERTIFICATE and CERTIFICATE transmission / reception stages can be omitted. Also, the power contract can be renewed in the renegotiation phase depending on the authentication result.

[0250] [Table 7]

[0251] Table 7 shows other examples of the requested time for each authentication message when the power contract is based on the results of GET_DIGESTS during the negotiation phase. If the wireless power receiver already knows the DIGEST regarding the wireless power transmitter, the GET_CERTIFICATE and CERTIFICATE transmission / reception stages can be omitted. Also, the power contract can be renewed in the renegotiation phase depending on the authentication result. The authentication procedure for satisfying the aforementioned requested time is disclosed below.

[0252] FIG. 18 is a flowchart showing the sequence of packets transmitted and received when a wireless power receiving device performs authentication of a wireless power transmitting device (authentication of PTx by PRx).

[0253] As shown in FIG. 18, the wireless power receiving device transmits GET_DIGESTS to the wireless power transmitting device in order to obtain or retrieve the certificate chain DIGESTS of the wireless power transmitting device (S1800). Here, REQUEST is set to PTx’s DIGEST. The prerequisite operation for step S1800 can include an operation of confirming the support of the authentication function with a performance packet received by the wireless power receiving device from the wireless power transmitting device. The wireless power receiving device can transmit GET_DIGESTS to the wireless power transmitting device using a general request packet during the negotiation phase or the renegotiation phase. That is, GET_DIGESTS can be transmitted by being carried on a general request packet.

[0254] FIG. 19 is an example of the message structure of GET_DIGESTS. As shown in FIG. 19, GET_DIGESTS is, for example, 1 byte and includes a request field. The request field can indicate, for example, the header of the DIGEST of the wireless power transmitting device.

[0255] FIG. 20 is another example of the message structure of GET_DIGESTS. As shown in FIG. 20, GET_DIGESTS is, for example, 1 byte and includes a reserved and a slot number. The slot number identifies the slot in which the requested certificate chain is stored and can be, for example, 3 bits.

[0256] Again in Figure 18, the wireless power transmitter sends DIGESTS to the wireless power receiver as a response to GET_DIGESTS (S1805). DIGESTS is used to send a report from the authentication responder regarding the certificate chain digests and which slots contain valid certificate chain digests. The parameters of DIGESTS may be 32 bytes of the hash value of the certificate chain.

[0257] Figure 21 shows the physical packet structure of a DIGESTS packet and how it is transmitted. As shown in Figure 21, a DIGESTS packet includes a 32-byte DIGESTS payload, a 1-byte header indicating that the packet concerns a DIGESTS, and a 2-byte header indicating the length of the packet. The radio power transmitter, on the other hand, divides such a DIGESTS packet into several small packets of a specific length (e.g., 3 bytes), adds a checksum to the end of each small packet, and transmits them as a sequence of 4-byte DIGESTS small packets. The size of the last small packet in such a sequence may be less than 4 bytes. Small packets can also be called segments. The example in Figure 21 limits the size of the packets transmitted by the radio power transmitter so that a single authentication response consists of a maximum of 4 bytes. Dividing a single response message into a series of small packets in this way allows for the timing of the (extended) control error packets (CEP) and (extended) received power packets (RPP) that the wireless power receiver periodically (approximately 250 ms) sends to the transmitter, thereby enabling efficient management of the operating point for power transmission and foreign object detection of the wireless power transmitter.

[0258] Again in Figure 18, if it is confirmed (acknowledge) that the wireless power transmitter has already been authenticated previously, the authentication is successful. If the wireless power receiver does not acknowledge the DIGESTS, the wireless power receiver continues the authentication during the power transmission phase. Steps S1800 and S1805 can be performed in the negotiation or renegotiation phase. Alternatively, steps S1800 and S1805 can be performed in the power transmission phase.

[0259] Next, the wireless power receiver sends GET_CERTIFICATE to the wireless power transmitter to obtain the certificate chain from the wireless power transmitter (S1810). Here, GET_CERTIFICATE is set by the offset and length. GET_CERTIFICATE is used to read a segment of the target certificate chain.

[0260] Figure 22 shows an example of the message structure of GET_CERTIFICATE. As shown in Figure 22, GET_CERTIFICATE can be, for example, 2 bytes and may include offset and length fields. Here, the offset is the offset in bytes from the start of the Certificate Chain to where the read request begins, and the length is the length in bytes of the read request. For example, to read 4 bytes from the start of the Certificate Chain, GET_CERTIFICATE may have an offset of [11...0] = 00b and a length of 11b.

[0261] Again in Figure 18, the wireless power transmitter transmits at least a portion of the certificate chain to the wireless power receiver as a response to GET_CERTIFICATE (S1815). At this time, the portion of the certificate chain may start a number of bytes later than the starting point.

[0262] Figure 23 shows an example of the physical packet structure and transmission method for a Certificate. As shown in Figure 23, when the wireless power transmitter transmits a 1536-byte Certificate packet, it extracts a 4-byte portion of the Certificate from the offset point of the Certificate packet, adds a header indicating that it is a Certificate to the front end, and adds a checksum to the rear end to generate and transmit a Certificate segment with a total length of 6 bytes.

[0263] Figure 24 shows an example of the physical packet structure and method of transmission for authentication response messages sent by a wireless power transmitter. As shown in Figure 24, an authentication packet (e.g., 1543 bytes) may include an authentication chain (e.g., 1540 bytes), a header indicating that it is an authentication (e.g., 1 byte), and a header indicating the length of the authentication packet (e.g., 2 bytes). The wireless power transmitter, on the other hand, divides such an authentication packet into multiple small packets of a specific length (e.g., 3 bytes), adds a checksum to the end of each small packet, and transmits them as a sequence of 4-byte authentication small packets. In this case, a total of 515 data chunks are transmitted, each of which is smaller than 4 bytes. The size of the last small packet in the sequence may be less than 4 bytes. Small packets can also be called segments. The example in Figure 24 limits the size of the wireless power transmitter's transmitted packets so that a single authentication response consists of a maximum of 4 bytes. Dividing a single response message into a series of small packets in this way allows for the timing of the (extended) control error packets (CEP) and (extended) received power packets (RPP) that the wireless power receiver periodically (approximately 250 ms) sends to the transmitter, thereby enabling efficient management of the operating point for power transmission and foreign object detection of the wireless power transmitter.

[0264] Again in Figure 18, if necessary, the wireless power receiver may transmit a control error (CE) packet and / or a received power packet (RPP) to the wireless power transmitter (S1820). Steps S1810 and S1820 can be performed, for example, in the power transfer phase.

[0265] From this point onward, the wireless power receiver can repeat steps S1810 through S1820 until it has read the entire certificate chain.

[0266] The wireless power receiver transmits CHALLENGE to the wireless power transmitter (S1825). CHALLENGE is used to initiate product certification.

[0267] Figure 25 shows an example of a CHALLENGE message structure. As shown in Figure 25, a CHALLENGE message can be, for example, 32 bits (4 bytes) and contain four Nonce fields. A Nonce is a binary random number selected by the authentication initiator.

[0268] Again in Figure 18, the wireless power receiver sends GET_CHALLENGE_AUTH to the wireless power transmitter in order to obtain CHALLENGE_AUTH (S1830). Here, GET_CHALLENGE_AUTH can be set by offset and length.

[0269] The wireless power transmitter transmits a portion of CHALLENGE_AUTH to the wireless power receiver as a response to GET_CHALLENGE_AUTH (S1835). At this time, the portion of CHALLENGE_AUTH may start a number of bytes later than the starting point.

[0270] Figure 26 shows an example of the physical packet structure to which CHALLENGE_AUTH is sent and how it is sent. As shown in Figure 26, a CHALLENGE_AUTH packet (e.g., 1600 bytes) can include a certificate chain hash (e.g., 32 bytes), a salt (e.g., 32 bytes), a context hash (e.g., 32 bytes), and a signature (e.g., 64 bytes). Meanwhile, the radio power transmitter extracts a portion of such a CHALLENGE_AUTH packet from the offset, specifying a certain length (e.g., 4 bytes), adds a header indicating that it is a CHALLENGE_AUTH packet to the front end and a checksum to the back end to generate a certificate segment with a total length of 6 bytes, and sends it.

[0271] Again in Figure 18, if necessary, the wireless power receiver may transmit a control error (CE) packet and / or a received power packet (RPP) to the wireless power transmitter (S1840).

[0272] From this point onward, the wireless power receiver can repeat steps S1830 through S1840 until it has read the entire certificate chain.

[0273] Next, we will describe the procedure by which the wireless power transmitter authenticates the wireless power receiver based on the authentication message.

[0274] (2) Authentication of a wireless power receiving device by a wireless power transmitting device (Authentication of PRx by PTx)

[0275] When authentication of a wireless power transmitter (PRx by PTx) is performed based on in-band communication, the required time for each stage is as shown in Table 8 or Table 9.

[0276] [Table 8]

[0277] Table 8 shows an example of the request time for each authentication message when the power contract is based on the results of GET_DIGESTS during the negotiation phase. If the wireless power transmitter already knows the DIGEST for the wireless power receiver, the GET_CERTIFICATE and CERTIFICATE transmission / reception stages can be omitted. Also, the power contract can be renewed in the renegotiation phase depending on the authentication result.

[0278] [Table 9]

[0279] Table 9 shows an example of the required time for each authentication message when the power contract is based on the results of GET_DIGESTS during the negotiation phase. If the wireless power transmitter already knows the DIGEST regarding the wireless power receiver, the control error packet transmission stage, the communication request stage, and the GET_CERTIFICATE and CERTIFICATE transmission / reception stages can be omitted. Also, the power contract can be renewed in the renegotiation phase depending on the authentication result. The authentication procedure for satisfying the above required time is disclosed below.

[0280] Figure 27 is a flowchart showing the sequence of packets transmitted and received when a wireless power transmitter according to one embodiment performs authentication of a wireless power receiver (PRx by PTx).

[0281] As shown in Figure 27, the wireless power transmitter receives DIGESTS transmitted from the line power receiver (S2700). DIGESTS are used to send a report from the authentication responder regarding the certificate chain digests and which slots contain valid certificate chain digests. The parameters of DIGESTS may be 32 bytes of the hash value of the certificate chain. Preliminary actions for step S2700 may include the wireless power receiver confirming support for the authentication function in the capability packet received from the wireless power transmitter, and the wireless power transmitter sending GET_DIGESTS to the wireless power receiver. Step S2700 may occur in the negotiation or renegotiation phase or the power transmission phase.

[0282] Figure 28 shows an example of the message structure of GET_DIGESTS transmitted by a wireless power transmitter. As shown in Figure 28, GET_DIGESTS is, for example, 1 byte and includes a request field, a reserved field, and a slot number. The slot number identifies the slot in which the requested certificate chain is stored and may be, for example, 3 bits.

[0283] Again in Figure 27, during the power transmission phase, the wireless power receiver transmits a control error packet or a received power packet to the wireless power transmitter (S2705).

[0284] The wireless power transmitter transmits a request for communication in response to a control error packet or a received power packet (S2710). The request for communication may be, for example, a bit pattern response.

[0285] When the wireless power receiver responds with an ACK to a request to initiate communication (S2715), the wireless power transmitter sends GET_CERTIFICATE to the wireless power receiver to obtain the certificate chain or CHALLENGE_AUTH response (S2720). Here, GET_CERTIFICATE is set by an offset and a length. GET_CERTIFICATE is used to read a segment of the target certificate chain.

[0286] Figure 29 shows an example of the GET_CERTIFICATE message structure transmitted by a wireless power transmitter. As shown in Figure 29, GET_CERTIFICATE can be, for example, 2 bytes and may include offset and length fields. Here, the offset is the offset in bytes from the start of the Certificate Chain to where the read request begins. The length is the length in bytes of the read request. For example, to read 40 bytes from the start of the Certificate Chain, GET_CERTIFICATE may have an offset [7...0] = 00b and a length value of 110000b.

[0287] Again in Figure 27, the wireless power receiver transmits at least a portion of the certificate chain to the wireless power transmitter as a response to GET_CERTIFICATE (S2725). At this time, the portion of the certificate chain may start a number of bytes later than the starting point.

[0288] Figure 30 shows an example of the physical packet structure and transmission method for a Certificate sent by a wireless power receiver. As shown in Figure 30, when the wireless power receiver transmits a 1536-byte Certificate packet, it extracts 40 bytes of the Certificate from the offset point of the Certificate packet, adds a header (e.g., 1 byte) indicating that it is a Certificate to the front end, and adds a checksum (e.g., 1 byte) to the rear end to generate a Certificate segment with a total length of 42 bytes, which is then transmitted.

[0289] Again in Figure 27, the wireless power transmitter can repeat steps S2710 to S2725 until it has read out the entire certificate chain.

[0290] If necessary, the wireless power receiver may transmit control error (CE) packets and / or received power packets (RPP) to the wireless power transmitter (S2730).

[0291] The wireless power transmitter transmits a request for communication in response to a control error packet or a received power packet (S2735). The request for communication may be, for example, a bit pattern response.

[0292] When the wireless power receiver responds with an ACK to the request to initiate communication (S2740), the wireless power transmitter sends CHALLENGE[n] to the wireless power receiver (S2745). CHALLENGE is used to initiate product authentication.

[0293] Figure 31 shows an example of the structure of a CHALLENGE message transmitted by a wireless power transmitter. As shown in Figure 31, a CHALLENGE message can be, for example, 32 bits (4 bytes) and may contain four Nonce fields. A Nonce is a binary random number selected by an authentication initiator. The wireless power transmitter can provide a wireless power receiver with a total of 32 bytes of Nonce by transmitting eight CHALLENGE packets.

[0294] Again in Figure 27, after the wireless power transmitter receives an ACK from the wireless power receiver, it can repeat steps S2735 to S2750 until it has transmitted all of the CHALLENGE messages.

[0295] The wireless power receiver may transmit control error packets and / or received power packets to the wireless power transmitter (S2755). The wireless power transmitter transmits a request for communication in response to the control error packet or received power packet (S2760). The request for communication may be, for example, a bit pattern response.

[0296] When the wireless power receiver responds with an ACK to a request to initiate communication (S2765), the wireless power transmitter sends GET_CHALLENGE_AUTH to the wireless power receiver to obtain CHALLENGE_AUTH (S2770). Here, GET_CHALLENGE_AUTH can be set by an offset and a length.

[0297] The wireless power receiver transmits at least a portion of CHALLENGE_AUTH to the wireless power transmitter as a response to GET_CHALLENGE_AUTH (S2775). At this time, at least a portion of CHALLENGE_AUTH may start a number of bytes later than the point in time when it begins.

[0298] Figure 32 shows an example of the physical packet structure and method of transmission for CHALLENGE_AUTH transmitted by a wireless power receiver. As shown in Figure 32, a CHALLENGE_AUTH packet (e.g., 160 bytes) can include a certificate chain hash (e.g., 32 bytes), a salt (e.g., 32 bytes), a context hash (e.g., 32 bytes), and a signature (e.g., 64 bytes). Meanwhile, a wireless power transmitter extracts a portion of such a CHALLENGE_AUTH packet from the offset to a specific length (e.g., 40 bytes) based on the offset and length indicated by GET_CHALLENGE_AUTH, adds a header (e.g., 1 byte) indicating that it is a CHALLENGE_AUTH packet to the front end and a checksum (e.g., 1 byte) to the back end to generate and transmit a certificate segment with a total length of 42 bytes.

[0299] From this point onward, the wireless power transmitter can repeat steps S2760 to S2775 until all CHALLENGE_AUTH values ​​have been read.

[0300] Figure 33 shows an example of the physical packet structure and method of transmission for authentication response messages sent by a wireless power receiver. As shown in Figure 33, for example, an authentication packet (e.g., N bytes) may include an authentication chain, a header indicating that it is an authentication (e.g., 1 byte), and a header indicating the length of the authentication packet (e.g., 2 bytes). The wireless power receiver, on the other hand, divides such an authentication packet into multiple small packets of a specific length (e.g., M-1 bytes), adds a 1-byte checksum to the end of each small packet, and transmits them as a sequence of M-byte authentication small packets. The size of the last small packet in the sequence may be less than M bytes. Small packets can also be called segments. The example in Figure 33 limits the size of the packets transmitted by the wireless power receiver so that one authentication response consists of M bytes. Dividing a single response message into a series of small packets in this way allows for the timing of the (extended) control error packets (CEP) and (extended) received power packets (RPP) that the wireless power receiver periodically (approximately 250 ms) sends to the transmitter, thereby enabling efficient management of the operating point and foreign object detection for power transmission by the wireless power transmitter.

[0301] Figure 34 shows another example of the physical packet structure to which an authentication response message from a wireless power receiver is transmitted, and how it is transmitted. As shown in Figure 34, for example, an authentication packet (e.g., 1543 bytes) may include an authentication chain (e.g., 1540 bytes), a header indicating that it is an authentication (e.g., 1 byte), and a header indicating the length of the authentication packet (e.g., 2 bytes). The wireless power receiver, on the other hand, divides such an authentication packet into multiple small packets of a specific length (e.g., 38 bytes), adds a preamble (e.g., 1 byte) to the front end of each small packet and a checksum (e.g., 1 byte) to the back end, and transmits them as a sequence of 40-byte authentication small packets. In this case, a total of 41 data chunks are transmitted. The size of the last small packet in the sequence may be less than 40 bytes. Small packets can also be called segments. The example in Figure 34 limits the size of the packets transmitted by the wireless power receiver so that one authentication response consists of 40 bytes. Dividing a single response message into a series of small packets in this way allows for the timing of the (extended) control error packets (CEP) and (extended) received power packets (RPP) that the wireless power receiver periodically (approximately 250 ms) sends to the transmitter, thereby enabling efficient management of the operating point and foreign object detection for power transmission by the wireless power transmitter.

[0302] Figure 35 is a flowchart showing the sequence of packets transmitted and received when a wireless power transmitter according to another embodiment performs authentication of a wireless power receiver (PRx by PTx).

[0303] As shown in Figure 35, the wireless power transmitter receives DIGESTS transmitted from the wireless power receiver (S3500). Preliminary actions for step S3500 may include the wireless power receiver checking for support for the authentication function from the capability packet received from the wireless power transmitter, and the wireless power transmitter sending GET_DIGESTS to the wireless power receiver. Step S3500 can be performed in the negotiation phase or the power transmission phase.

[0304] During the power transmission phase, the wireless power receiver transmits a control error packet or a received power packet to the wireless power transmitter (S3505).

[0305] The wireless power transmitter transmits a request for multiple communication (S3510) in response to a control error packet or a received power packet. The request for multiple communication may be, for example, a bit pattern response.

[0306] When the wireless power receiver responds with an ACK to a request for multiple communications (S3515), the wireless power transmitter sends GET_CERTIFICATE to the wireless power receiver to obtain the certificate chain or CHALLENGE_AUTH response from the wireless power receiver (S3520). Here, GET_CERTIFICATE is set by an offset and a length. GET_CERTIFICATE is used to read a segment of the target certificate chain.

[0307] The wireless power receiver transmits at least a portion of the certificate chain to the wireless power transmitter in response to GET_CERTIFICATE (S3525). At this time, the portion of the certificate chain may start a number of bytes later than the starting point.

[0308] The wireless power transmitter may repeat steps S3520 to S3525 until it has read the entire certificate chain.

[0309] If necessary, the wireless power receiver may transmit control error (CE) packets and / or received power (RPP) packets to the wireless power transmitter (S3530).

[0310] The wireless power transmitter transmits a request for multiple communications in response to a control error packet or a received power packet (S3535). The request for multiple communications may be, for example, a bit pattern response.

[0311] When the wireless power receiver responds with an ACK to a request for multiple communications (S3540), the wireless power transmitter sends CHALLENGE[n] to the wireless power receiver (S3545). CHALLENGE is used to initiate product authentication.

[0312] After receiving an ACK from the wireless power receiver (S3550), the wireless power transmitter can repeat steps S3545 through S3550 until it has transmitted all of the CHALLENGE messages.

[0313] The wireless power receiver may transmit control error packets and / or received power packets to the wireless power transmitter (S3555). The wireless power transmitter transmits a request for multiple communications in response to the control error packet or received power packet (S3560). The request for multiple communications may be, for example, a bit pattern response.

[0314] When the wireless power receiver responds with an ACK to a request for multiple communications (S3565), the wireless power transmitter sends GET_CHALLENGE_AUTH to the wireless power receiver to obtain CHALLENGE_AUTH (S3570). Here, GET_CHALLENGE_AUTH can be set by an offset and a length.

[0315] The wireless power receiver transmits at least a portion of CHALLENGE_AUTH to the wireless power transmitter as a response to GET_CHALLENGE_AUTH (S3575). At this time, at least a portion of CHALLENGE_AUTH may start at an offset from the point in time when it begins in byte units.

[0316] From this point onward, the wireless power transmitter can repeat steps S3570 to S3575 until all CHALLENGE_AUTH values ​​have been read.

[0317] 5. Lower-level protocols that support authentication procedures

[0318] Since low-level packet transmission protocols that support authentication procedures may be based on in-band communication, the packet structure used in in-band communication must be configured to conform to the authentication procedure and authentication messages.

[0319] Figure 36 shows the structure of a packet transmitted by a wireless power receiver to a wireless power transmitter in in-band communication. The packet shown in Figure 36 can be modified using the ASK method.

[0320] As shown in Figure 36, the bit rate is 2 Kbps, and the packet includes a preamble, header, message, and checksum. For example, the preamble is set to 11 bits, the heather to 1B, and the checksum to 1B (1B → 11 bits).

[0321] Figure 37 shows the structure of a packet transmitted by a wireless power transmitter to a wireless power receiver in in-band communication. The packet shown in Figure 37 can be modulated using the FSK method.

[0322] As shown in Figure 37, the bit rate at a 100kHz operating frequency is 200bps, and a packet includes a header, message, and checksum. For example, the header is set to 1B and the checksum to 1B (1B → 11 bits).

[0323] (1) Lower-level authentication sequence

[0324] 1) Authentication of PTx by PRx using a wireless power receiving device.

[0325] If the wireless power receiver is the authentication initiator, the wireless power transmitter becomes the authentication responder. Alternatively, the wireless power transmitter can be represented as the (authenticated) device. As the authentication initiator, the wireless power receiver sends a message (or packets) to the wireless power transmitter requesting the message (or packets) necessary for the authentication of the wireless power transmitter. As the authentication responder, the wireless power transmitter sends an authentication response message to the wireless power receiver, consisting of a sequence of various packets. This sequence of sending and receiving messages can be defined by a lower-level packet transmission protocol.

[0326] Figure 38 shows the packet transmission and reception sequence between a wireless power receiver and a wireless power transmitter from a lower-level perspective according to one embodiment. Figure 38 shows the process by which the wireless power transmitter sends an authentication response packet (DIGESTS) to the wireless power receiver in response to the wireless power receiver sending GET_DIGESTS.

[0327] As shown in Figure 38, the radio power transmitter waits for an ACK / NACK or continue / stop to be sent from the radio power receiver after each packet of the sequence has been transmitted. The ACK / NACK or continue / stop is transmitted in an extended control error packet (CEP) as shown in Figure 39. The radio power transmitter and / or receiver repeat the following procedure until all packets of the sequence have been transmitted.

[0328] If the wireless power transmitter receives an "ACK and persistence", it will send the next packet.

[0329] If the wireless power transmitter receives "ACK and interruption," it waits until it receives the next extended CEP containing "ACK and persistence."

[0330] If the wireless power transmitter receives a "NACK and persistence," the wireless power transmitter will retransmit the previous packet.

[0331] If the wireless power transmitter receives a "NACK and interruption," it waits until it receives the next extended CEP, which includes an "ACK and persistence."

[0332] Figure 39 shows the packet transmission and reception sequence between a wireless power receiver and a wireless power transmitter from a lower-level perspective according to another embodiment. Figure 39 shows the process by which the wireless power transmitter sends an authentication response packet (CERTIFICATE) to the wireless power receiver in response to the wireless power receiver sending GET_CERTIFICATE.

[0333] As shown in Figure 39, the radio power transmitter waits for an ACK / NACK or continue / stop to be sent from the radio power receiver after each packet of the sequence has been transmitted. The ACK / NACK or continue / stop is transmitted in an extended control error packet (CEP) as shown in Figure 39. The radio power transmitter and / or receiver repeat the following procedure until all packets of the sequence have been transmitted.

[0334] If the wireless power transmitter receives an "ACK and persistence," it will send the next packet. For example, for packet (1), it may receive an "ACK and persistence" via an Extended Control Error Packet (CEP), and for packet (m), it may receive an "ACK and persistence" via an Extended Received Power Packet (Extended RPP) as shown in Figure 42.

[0335] If the wireless power transmitter receives an "ACK and interruption," it waits until it receives the next extended CEP containing an "ACK and persistence." For example, for packet (n), it receives an "ACK and interruption" via an extended CEP.

[0336] If the wireless power transmitter receives a "NACK and persistence," the wireless power transmitter will retransmit the previous packet.

[0337] If the wireless power transmitter receives a "NACK and interruption," it waits until it receives the next extended CEP, which includes an "ACK and persistence."

[0338] Figure 40 shows the structure of an extended control error packet according to one embodiment.

[0339] As shown in Figure 40, the wireless power receiver transmits an extended control error packet in response to a packet from the wireless power transmitter. The extended control error packet includes not only a control error value that adjusts the operating point of the wireless power transmitter, but also at least one of ACK / NACK or continue / stop.

[0340] For example, the interruption is a 1-bit value, where '1'b indicates that the radio power transmitter will interrupt the transmission of packets, and '0'b indicates that the radio power transmitter will transmit the next packet in the sequence (i.e., continue transmission). Here, when the radio power receiver needs to transmit a CEP in a short period to quickly adjust the operating point of the radio power transmitter, or when all response packets have been received, the radio power receiver can enforce the radio power transmitter to suspend transmission of packets in the next sequence by setting the interruption to '1'.

[0341] ACK / NACK are, for example, 4 bits, with a value of '0000'b indicating ACK and a value of '1111'b indicating NACK. ACK indicates that the radio power receiver has successfully received the packet without any error conditions, while NACK indicates that the radio power receiver has requested the radio power transmitter to retransmit the packet due to a packet reception error.

[0342] Figure 41 shows the structure of an end power transfer (EPT) packet according to one embodiment.

[0343] As shown in Figure 41, the power transmission termination packet corresponding to header value 0x02 can indicate a code value required for the authentication procedure. For example, if authentication of the wireless power transmitter fails, the wireless power receiver can set the EPT code value to indicate a different code value from the conventional EPT code, such as 0x0E. By transmitting the new EPT code value, the wireless power receiver can remove the power transmission.

[0344] Figure 42 shows the structure of an extended received power packet according to one embodiment.

[0345] As shown in Figure 42, the extended received power packet is 24 bits and may include a first spare bit, mode, received power value, second spare bit, stop, and ACK / NACK. That is, the extended received power packet not only includes the received power value associated with the FOD of the radio power transmitter, but also includes at least one of ACK / NACK or continue / stop.

[0346] For example, the interruption is a 1-bit value, where '1'b means the radio power transmitter interrupts packet transmission, and '0'b means the radio power transmitter transmits the next packet in the sequence (i.e., continues transmission). Here, when the radio power receiver needs to transmit a CEP in a short period to quickly adjust the operating point of the radio power transmitter, or when all response packets have been received, the radio power receiver can enforce the radio power transmitter to suspend transmission of packets in the next sequence by setting the interruption to '1'.

[0347] ACK / NACK are, for example, 4 bits, with a value of '0000'b indicating ACK and a value of '1111'b indicating NACK. ACK indicates that the radio power receiver has successfully received the packet without any error conditions, while NACK indicates that the radio power receiver has requested the radio power transmitter to retransmit the packet due to a packet reception error.

[0348] 2) Authentication of a wireless power receiver by a wireless power transmitter (Authentication of PRx by PTx)

[0349] If the wireless power transmitter is the authentication initiator, the wireless power receiver becomes the authentication responder. Alternatively, the wireless power receiver can be represented as the (authenticated) device. As the authentication initiator, the wireless power transmitter sends a message (or packets) to the wireless power receiver requesting the message (or packets) necessary for the authentication of the wireless power receiver. As the authentication responder, the wireless power receiver sends an authentication response message to the wireless power transmitter, consisting of a sequence of various packets. This process of sending and receiving a series of messages can be defined by a lower-level packet transmission protocol.

[0350] Figure 43 shows the packet transmission and reception sequence between a wireless power receiver and a wireless power transmitter from a lower-level perspective according to one embodiment. Figure 43 shows the process by which the wireless power receiver receives an authentication response packet (CERTIFICATE) from the wireless power transmitter after the wireless power transmitter sends GET_CERTIFICATE to the wireless power transmitter.

[0351] As shown in Figure 43, the radio power receiver waits for an ACK / NACK (bit pattern response) to be sent from the radio power transmitter after each packet of the sequence has been transmitted. The bit response time may be, for example, 40 ms. The radio power transmitter and / or receiver may repeat the following procedure until all packets of the sequence have been transmitted. Between authentication response packets, the radio power receiver may also transmit a CEP and / or RPP.

[0352] If the wireless power receiver receives an "ACK," it will send the next packet. For example, if it receives an ACK for packet (1), it will send packet (2) at the next transmission timing.

[0353] If the wireless power receiver receives a "NACK," it will retransmit the previous packet.

[0354] (2) Lower-level data exchange protocols (protocol for data transaction)

[0355] The following describes a data transaction protocol. For lower-level data exchange, this embodiment considers four rules.

[0356] Rule 1 is that the radio power receiver operates as the master. When the radio power receiver operates as the master and the radio power transmitter operates as the slave, the radio power receiver determines when communication from the radio power transmitter is permitted.

[0357] A wireless power receiver can send a start of data stream (SOD) ADT_CTRL packet to inquire whether there is a data stream to be transmitted by the wireless power transmitter. Alternatively, the wireless power receiver can send a general request packet (GRP) with a request value set to "0xFF" to poll (pool) the wireless power transmitter to see if there are any packets to send.

[0358] Rule 2 is communication error control. The radio power receiver or transmitter may rewrite ADT packets until it receives an ACK. Additionally, an "ACK" ADT_CTRL packet is sent when no communication error occurs, and a "NACK" ADT_CTRL packet is sent when a communication error is detected.

[0359] Rule 3 is data stream synchronization. For synchronization, the header of the ADT data packet can be toggled each time a new ADT data packet is sent.

[0360] Rule 4 is to mark the end of the data stream, or to mark both the end and the start. Specifically, a start of data stream (SOD) ADT_CTRL packet can be added to the start of the data stream, or an end of data stream (EOD) ADT_CTRL packet can be added to the end of the data stream. Here, SOD and EOD are added when the length of the data stream is greater than one packet.

[0361] Based on the aforementioned rules, the data transport and packet structure can be defined as follows:

[0362] 1) Lower-level data transport and packet structure for authentication

[0363] The following section provides a detailed explanation of the lower-level data transport and packet structure for authentication. Lower-level data transport design methods are broadly categorized into two types: dedicated mapping and generic bit pipe. The generic bit pipe method offers application-agnostic data transmission and has the advantage of being usable for other applications in addition to authentication.

[0364] The design requirements for lower-level data transport in a general bit pipe infrastructure are: i) minimizing interaction between the high level and the lower level, and ii) ensuring error-recovery and synchronized lower-level data transport. In relation to i), the high level encodes and pushes (writes) data streams to the lower level and decodes (reads) data streams provided by the lower level. The lower level also records or reads data streams using multiple auxiliary data transport (ADT) data packets. In relation to ii), a simple and robust communication error-recovery mechanism includes rewriting ADT packets until the radio power transmitter or receiver receives an ACK, and rereading ADT packets until there are no communication errors. Furthermore, simple synchronization of the data stream between the wireless power transmitter and receiver involves toggling the data packet header when transporting a new ADT data packet.

[0365] Figure 44 shows a data transport according to one embodiment. Figure 44 is an update data transport (UDT).

[0366] As shown in Figure 44, the update data transport is used to carry update data. The update data includes several data packets. For example, the update data may include a control error packet (CEP), a received power packet (RPP) selectively containing an ACK or NACK, an auxiliary data transport (ADT), a charge status packet (CSP), a proprietary packet, a renegotiation (RNG) packet selectively containing an ACK or NACK, and a spare packet (the radio power transmitter must be resilient to spare bits).

[0367] ADT is a lower-level data packet or transport for higher-level applications, and includes the same logical layer packets as the performance packets of a wireless power transmitter.

[0368] Figure 45 shows a data transport according to another embodiment. Figure 45 is an auxiliary data transport (ADT).

[0369] As shown in Figure 45, the ADT includes an ADT (ADT_PRx) for the radio power receiver and an ADT (ADT_PTx) for the radio power transmitter.

[0370] The ADT for a radio power receiver carries data or response (e.g., ACK, NACK, RFA) packets or control packets from the radio power receiver.

[0371] The ADT for a radio power transmitter carries data or response (e.g., ACK, NACK, RFA) packets or control packets or ACK / NACK / RFA bit pattern responses from the radio power transmitter.

[0372] As an example, the header of an ADT packet may indicate lower-level data packets for a higher-level application (e.g., lower-level data packets for a wireless power receiver or a wireless power transmitter). The higher-level application may include, for example, authentication procedures, proprietary information exchange, firmware updates, or capabilities control for wireless power transmitters.

[0373] As another example, the header of an ADT packet may indicate a logical layer data packet (e.g., a packet from a wireless power receiver or a packet from a wireless power transmitter). Yet another example is that the header of an ADT packet may include a control packet.

[0374] As another example, the header of an ADT packet can indicate an ADT data packet, in which case the header of the ADT data packet can contain multiple types of headers (for example, Header A and Header B, thus two types of headers). Synchronization of the data stream can be achieved by toggling the header of the ADT data packet between A and B or B and A each time a new ADT data packet is sent.

[0375] As another example, the header of an ADT packet may indicate an ADT control packet, in which case the header of the ADT packet may contain a single type of header.

[0376] The following describes the ADT packet structure as a low-level data transport. As mentioned above, the ADT consists of a pair of ADTs: one for the radio power receiver (ADT_PRx) and one for the radio power transmitter (ADT_PTx). The ADT for the radio power receiver (ADT_PRx) is the first to be introduced.

[0377] Figure 46 shows the structure of an ADT data packet (ADT_PRx Data Packet) related to a wireless power receiving device according to one embodiment.

[0378] As shown in Figure 46, an ADT data packet contains, for example, a payload of (n+1) bytes, and each payload can correspond to one of several header types. Table 10 shows the correspondence between the payload size (up to 16 bytes when n=15) and the headers of an ADT data packet.

[0379] [Table 10]

[0380] Referring to Table 10, when a payload of a specific number of bytes is included in an ADT data packet and transmitted, either header A or header B can be used. The size of the payload can range from 1 to 16 bytes. The radio power receiver and radio power transmitter can synchronize with each other by agreeing to specify a pattern of header values ​​when sending a new ADT data packet and when retransmitting the previous ADT data packet. For example, in a situation where a radio power receiver transmits a 1-byte payload in an ADT data packet, the radio power receiver can toggle the header value from header A (=0x1C) to B (=0x1D) or from B (=0x1D) to A (=0x1C) when sending a new ADT data packet, and maintain the previous header value when retransmitting the previous ADT data packet. Situations in which the previous ADT data packet is retransmitted may include when the radio power receiver receives a NACK response from the radio power transmitter or when the radio power receiver detects a decoding error in the radio power transmitter.

[0381] Figure 47 shows the structure of an ADT response packet (ADT_PRx Response Packet) related to a wireless power receiving device according to one embodiment.

[0382] As shown in Figure 47, an ADT response packet for a wireless power receiver is, for example, 1 byte, and its value can indicate ACK, NACK, or RFA. Table 11 shows the correspondence between the payload value of the ADT response packet and its indicated content.

[0383] [Table 11]

[0384] In Table 11, a payload value of '11111111'b indicates that the radio power receiver successfully received and decoded the ADT data packet transmitted by the radio power transmitter in the previous ADT (ACK). A payload value of '00000000'b indicates that the radio power receiver either failed to successfully receive or decode the ADT data packet transmitted by the radio power transmitter in the previous ADT (NACK). In this case, the radio power transmitter retransmits the previous ADT data packet in the current ADT, and the header of the ADT data packet has a value corresponding to the retransmission of the previous data packet (e.g., 0x1C). A payload value of '00110011'b indicates that the radio power receiver has requested the radio power transmitter to send response data (RFA). In Table 11, the payload values ​​and their instructions are merely examples, and any number of different payload values ​​can be used for each instruction, and these also fall within the technical scope of the present invention.

[0385] On the other hand, the structure of the ADT control packet for the wireless power receiver may be identical to the ADT packet structure shown in Figure 47.

[0386] Figure 48 shows the structure of an ADT control packet (ADT_PRx Control Packet) related to a wireless power receiving device according to one embodiment.

[0387] As shown in Figure 48, an ADT control packet for a wireless power receiver is, for example, 1 byte, and its value can represent ACK, NACK, SOD, or EOD. Table 12 shows the correspondence between the payload value of the ADT control packet and its instruction.

[0388] [Table 12]

[0389] In Table 12, a payload value of '11111111'b indicates that the radio power receiver successfully received and decoded the ADT data packet transmitted by the radio power transmitter in the previous ADT (ACK). A payload value of '00000000'b indicates that the radio power receiver either failed to successfully receive or decode the ADT data packet transmitted by the radio power transmitter in the previous ADT (NACK). In this case, the radio power transmitter retransmits the previous ADT data packet in the current ADT, and the header of the ADT data packet has a value corresponding to the retransmission of the previous data packet (e.g., 0x1C). A payload value of '00110011'b indicates that the start of the ADT data stream has been requested (SOD). A payload value of '11001100'b indicates the end of the ADT data stream (EOD).

[0390] In Table 12, the payload values ​​and their instructions are merely examples; any number of different payload values ​​can be used for each instruction, and these also fall within the technical scope of the present invention.

[0391] The following disclosure concerns the ADT (ADT_PTx) for wireless power transmitters.

[0392] Figure 49 shows the structure of an ADT data packet (ADT_PTx Data Packet) related to a wireless power transmission device according to one embodiment.

[0393] As shown in Figure 49, an ADT data packet contains, for example, a payload of (n+1) bytes, and each payload can correspond to one of several header types. Table 13 shows the correspondence between the payload size (up to 4 bytes when n=3) and headers of an ADT data packet.

[0394] [Table 13]

[0395] Referring to Table 13, when a payload of a specific number of bytes is included in an ADT data packet and transmitted, either Header A or Header B can be used. The size of the payload can range from 1 to 4 bytes. The radio power transmitter and radio power receiver can synchronize with each other by agreeing to specify a pattern of header values ​​when transmitting a new ADT data packet and when retransmitting the previous ADT data packet. For example, in a situation where a radio power transmitter transmits a 1-byte payload in an ADT data packet, the radio power transmitter can toggle the header value from Header A (=0x1C) to Header B (=0x1D) or from Header B (=0x1D) to Header A (=0x1C) when transmitting a new ADT data packet, and maintain the previous header value when retransmitting the previous ADT data packet. The situation in which the previous ADT data packet is retransmitted may be when the radio power transmitter receives a NACK response from the radio power receiver or when the radio power transmitter detects a decoding error in the radio power receiver.

[0396] Figure 50 shows the structure of an ADT response packet (ADT_PTx Response Packet) related to a wireless power transmission device according to one embodiment.

[0397] As shown in Figure 50, an ADT response packet for a wireless power transmitter is, for example, 1 byte, and its value can indicate ACK, NACK, or RFA. Table 14 shows the correspondence between the payload value of the ADT response packet and its instruction.

[0398] [Table 14]

[0399] In Table 14, a payload value of '11111111'b indicates that the radio power transmitter successfully received and decoded the ADT data packet transmitted by the radio power receiver in the previous ADT (ACK). A payload value of '00000000'b indicates that the radio power transmitter either failed to successfully receive or decode the ADT data packet transmitted by the radio power receiver in the previous ADT (NACK). In this case, the radio power receiver retransmits the previous ADT data packet in the current ADT, and the header of the ADT data packet has a value corresponding to the retransmission of the previous data packet (e.g., 0x1C). A payload value of '00110011'b indicates that the radio power transmitter has requested the radio power receiver to send response data (RFA). In Table 14, the payload values ​​and their instructions are merely examples, and any number of different payload values ​​can be used for each instruction, and these also fall within the technical scope of the present invention.

[0400] Figure 51 shows the structure of an ADT response / control packet (ADT_PTx Response / Control Packet) related to a wireless power transmission device according to one embodiment.

[0401] As shown in Figure 51, an ADT response packet for a wireless power transmitter is, for example, 1 byte, and its value can indicate ACK or RFA. Table 15 shows the correspondence between the payload value of the ADT response packet and its instruction.

[0402] [Table 15]

[0403] In Table 15, a payload value of '11111111'b indicates that the radio power transmitter successfully received and decoded the ADT data packet transmitted by the radio power receiver in the previous ADT (ACK). A payload value of '00110011'b indicates that the radio power transmitter requested the radio power receiver to send response data (RFA). According to this embodiment, if the radio power transmitter failed to successfully receive or decode the ADT data packet transmitted by the radio power receiver in the previous ADT, the radio power transmitter does not send a separate communication error signal (NACK). In Table 15, the payload values ​​and their corresponding instructions are merely examples, and any number of different payload values ​​can be used for each instruction; these also fall within the technical scope of the present invention.

[0404] Figure 52 shows the structure of an ADT control packet (ADT_PTx Control Packet) related to a wireless power transmission device according to one embodiment.

[0405] As shown in Figure 52, an ADT control packet for a wireless power transmitter is, for example, 1 byte, and its value can represent ACK, NACK, SOD, or EOD. Table 16 shows the correspondence between the payload value of the ADT control packet and its instruction content.

[0406] [Table 16]

[0407] In Table 16, a payload value of '11111111'b indicates that the radio power transmitter successfully received and decoded the ADT data packet transmitted by the radio power receiver in the previous ADT (ACK). A payload value of '00000000'b indicates that the radio power transmitter either failed to successfully receive or decode the ADT data packet transmitted by the radio power receiver in the previous ADT (NACK). In this case, the radio power receiver retransmits the previous ADT data packet in the current ADT, and the header of the ADT data packet has a value corresponding to the retransmission of the previous data packet (e.g., 0x1C). A payload value of '00110011'b indicates that the start of the ADT data stream has been requested (SOD). A payload value of '11001100'b indicates the end of the ADT data stream (EOD). In Table 16, the payload values ​​and their instructions are merely examples; any number of different payload values ​​can be used for each instruction, and these also fall within the technical scope of the present invention.

[0408] The following describes an embodiment that implements an authentication sequence based on a lower-level data transport and packet structure, such as the ADT described above.

[0409] 2) Lower-level data exchange sequence for authentication (ADT infrastructure)

[0410] Figure 53 is a diagram showing a state machine related to ADT data packet recording (write) according to one embodiment.

[0411] As shown in Figure 53, the sender and / or receiver synchronize the data stream according to Rule 3 as shown in Figure 53. That is, each time a new ADT data packet [n] is sent for synchronization, the header of the ADT data packet [n] can be toggled. The header of the ADT packet can indicate an ADT data packet, in which case the header of the ADT data packet can contain multiple types of headers (e.g., Header A and Header B, thus two types of headers). Synchronization of the data stream can be achieved by toggling the header of the ADT data packet from A to B or B to A each time a new ADT data packet is successfully (ACK) sent. When the radio power receiver receives a NACK response from the radio power transmitter, or when the radio power receiver detects a decoding error in the radio power transmitter, it retransmits the previous ADT data packet, in which case the previous header value is maintained.

[0412] 2-1) Authentication of PTx by PRx using a wireless power receiving device.

[0413] As a lower-level authentication sequence for the ADT infrastructure, the authentication of a wireless power transmitter by a wireless power receiver is first described (PRx=Initiator / PTx=Responder).

[0414] Figure 54 illustrates the upper-level and high-level transmission sequences of the wireless power receiver and wireless power transmitter during the exchange of ADT data packets according to one embodiment.

[0415] As shown in Figure 54, H_A represents a type A header and H_b represents a type B header. When data number 1 from the upper level of the wireless power receiver (sender) is transmitted to the lower level and sent to the wireless power transmitter along with header A, the lower level of the wireless power transmitter transmits data number 1 to the upper level. If data number 1 is successfully received, the wireless power transmitter sends an ACK for data number 1 to the wireless power receiver. The wireless power receiver transmits the new data number 2 from the upper level to the lower level and then sends it to the wireless power transmitter along with header B. However, if the wireless power transmitter fails to receive data number 2, it sends a NACK to the wireless power receiver. Having received the NACK, the wireless power receiver retransmits data number 2 along with the previous header B. In this manner, the wireless power receiver and wireless power transmitter can ensure synchronization and realize a simple and robust error recovery and synchronization mechanism.

[0416] Figure 55 illustrates the upper-level and high-level transmission sequences of the wireless power receiver and wireless power transmitter during ADT data packet exchange according to another embodiment. Here, the wireless power receiver is the authentication initiator, and the wireless power transmitter is the authentication responder. ADT data packet exchange between the wireless power receiver and transmitter is performed by the aforementioned "(1) lower-level authentication sequence" and "(2) lower-level data exchange protocol".

[0417] As shown in Figure 55, the wireless power receiver generates an M-byte CHALLENGE message at the higher level and transmits it to the lower level, which then places it in an ADT data packet (or transport) and transmits it to the wireless power transmitter.

[0418] According to the lower-level authentication sequence, the ADT data packets relating to the CHALLENGE message may be transmitted in several parts. While the ADT data packets are transmitted in several parts according to rule 2, the radio power transmitter transmits an ACK / NACK from the lower level to the radio power receiver for each subsequent ADT data packet, propagating the ADT data packets to the higher level. After this series of processes, once the transmission of the CHALLENGE message (from the higher level's perspective) or the ADT data packets relating to the CHALLENGE message (from the lower level's perspective) is complete, the radio power receiver signals the completion of transmission by adding an EOD to the end of the ADT data packets relating to the CHALLENGE message, according to rule 4.

[0419] Meanwhile, the radio power receiver, in accordance with rule 1, queries whether the slave radio power transmitter has a data stream to transmit. For this purpose, the radio power receiver may transmit a State of Data (SOD). In this case, the radio power receiver may repeatedly transmit the SOD until the radio power transmitter responds with a data packet or a timeout occurs. When the radio power transmitter receives the SOD, it generates an N-byte CHALLENGE_AUTH_RESPONSE at the higher level and transmits it to the lower level, which then places it in an ADT data packet (or transport) and transmits it to the radio power receiver.

[0420] In accordance with the lower-level authentication sequence, the ADT data packet relating to the CHALLENGE_AUTH_RESPONSE message may be transmitted in several parts. While the ADT data packet is transmitted in several parts in accordance with rule 2, the radio power receiver transmits an ACK / NACK to the radio power transmitter for each subsequent ADT data packet from the lower level, propagating the ADT data packet to the higher level. After this series of processes, once the transmission of the CHALLENGE_AUTH_RESPONSE message (from the higher level's perspective) or the ADT data packet relating to the CHALLENGE_AUTH_RESPONSE message (from the lower level's perspective) is complete, the radio power transmitter signals the completion of transmission by appending an EOD to the end of the ADT data packet relating to the CHALLENGE_AUTH_RESPONSE message in accordance with rule 4.

[0421] Figure 56 illustrates the upper-level and high-level transmission sequences of the wireless power receiver and wireless power transmitter during ADT data packet exchange according to another embodiment.

[0422] The embodiment in Figure 56 differs from the embodiment in Figure 55 in that it strictly adheres to the addition of SOD and EOD according to Rule 4 each time an ADT data packet is sent, but uses a general request packet (GRP) instead of SOD for questioning (or polling) according to Rule 1.

[0423] Figure 57 illustrates the exchange sequence of ADT data packets related to an authentication request message according to one embodiment.

[0424] As shown in Figure 57, once a bitstream (e.g., 35 bytes) for the authentication message is prepared, the radio power receiver transmits an ADT data packet consisting of a header (e.g., 1 byte) and a payload (e.g., 34 bytes) to the lower level. Here, the authentication message could be, for example, a CHALLENGE message sent from the radio power receiver to the transmitter.

[0425] Since ADT data packets can transmit up to 16 bytes, the 35-byte authentication message is divided into three packets: a 16-byte ADT data packet 0 (ADT_PRx(0)), a 16-byte ADT data packet 1 (ADT_PRx(1)), and a 3-byte ADT data packet 2 (ADT_PRx(2)).

[0426] First, on the first line, the wireless power receiver successfully transmits the 0th ADT data packet (ADT_PRx(0)) and receives an ACK, but fails to transmit the 1st ADT data packet (ADT_PRx(1)) and receives a NACK. Subsequently, on the second line, the wireless power receiver retransmits the 1st ADT data packet (ADT_PRx(1)), but fails to receive a response (ACK or NACK) and sends a NACK. When the wireless power transmitter responds with an ACK, it is confirmed that the retransmission of the 1st ADT data packet (ADT_PRx(1)) was successful, so the wireless power receiver successfully transmits the remaining 3 bytes of the 2nd ADT data packet (ADT_PRx(2)) and receives an ACK. In response, the wireless power receiver successfully transmits an EOD and receives an ACK, thereby terminating the transmission of the authentication message.

[0427] Figure 58 illustrates the exchange sequence of ADT data packets for an authentication request message according to another embodiment. The embodiment in Figure 58 differs from the embodiment in Figure 57 in that the wireless power receiver divides a total of 35 bytes of the authentication message into a 16-byte 0th ADT data packet (ADT_PRx(0)), a 16-byte 1st ADT data packet (ADT_PRx(1)), and a 3-byte 2nd ADT data packet (ADT_PRx(2)) and transmits them, while performing simplified synchronization by toggling the header of each ADT data packet according to rule 3 (header A <-> header B), and using the same header used previously (header B in Figure 58) when retransmitting an ADT data packet, thereby instructing retransmission.

[0428] Figure 59 illustrates the exchange sequence of ADT data packets for an authentication request message according to another embodiment. The embodiment in Figure 59 is the same as the embodiment in Figure 58 in that the wireless power receiver divides the total 35 bytes of the authentication message into a 16-byte 0th ADT data packet (ADT_PRx(0)), a 16-byte 1st ADT data packet (ADT_PRx(1)), and a 3-byte 2nd ADT data packet (ADT_PRx(2)) and transmits them, and toggles the header of each ADT data packet according to rule 3 (header A <-> header B), but differs from the embodiment in Figure 58 in that an SOD is added at the start of transmission of the ADT data packets.

[0429] Figure 60 illustrates the exchange sequence of ADT data packets for an authentication request message according to another embodiment. The embodiment in Figure 60 differs from the embodiment in Figure 58 in that, when the wireless power receiver transmits a total of 35 bytes of authentication message by dividing it into a 16-byte 0th ADT data packet (ADT_PRx(0)), a 16-byte 1st ADT data packet (ADT_PRx(1)), and a 3-byte 2nd ADT data packet (ADT_PRx(2))), if the transmission of the 2nd ADT data packet (ADT_PRx(2))) fails, the 2nd ADT data packet (ADT_PRx(2)) is retransmitted with the header toggled, even though the header should not be toggled. Here, a bit pattern response can be used instead of an ADT response packet from the wireless power transmitter, thereby reducing the ADT exchange time.

[0430] Figure 61 is a diagram illustrating the exchange sequence of ADT data packets for an authentication request message according to another embodiment. The embodiment in Figure 61 illustrates a scenario in which a wireless power receiver divides a total of 35 bytes of an authentication message into a 16-byte 0th ADT data packet (ADT_PRx(0)), a 16-byte 1st ADT data packet (ADT_PRx(1)), and a 3-byte 2nd ADT data packet (ADT_PRx(2))) and transmits them, where the transmission of the 0th ADT data packet (ADT_PRx(0)) and the 16-byte 1st ADT data packet (ADT_PRx(1)) is successful, but there is no response to the 2nd ADT data packet (ADT_PRx(2))) and the transmission fails.

[0431] Figure 62 illustrates the exchange sequence of ADT data packets related to an authentication response message according to one embodiment.

[0432] As shown in Figure 62, a bitstream (e.g., 99 bytes) is prepared for the authentication response message. The authentication response message may be, for example, the CHALLENGE_AUTH_RESPONSE message sent from the wireless power transmitter to the receiver.

[0433] When using a PTx→PRx communication protocol (e.g., FSK), ADT data packets can be up to 4 bytes long. Therefore, a 99-byte authentication response message is divided and transmitted as a 4-byte 0th ADT data packet (ADT_PTx(0)), a 4-byte 1st ADT data packet (ADT_PTx(1)), ..., a 4-byte 23rd ADT data packet (ADT_PTx(23)), and a 3-byte 24th ADT data packet (ADT_PTx(24)).

[0434] First, when the wireless power receiver sends an SOD to the wireless power transmitter for boring, the wireless power transmitter successfully transmits the 0th ADT data packet (ADT_PTx(0)) and then receives an ACK. However, the wireless power transmitter fails to transmit the 1st ADT data packet (ADT_PTx(1)) and receives a NACK. Subsequently, the wireless power transmitter retransmits the 1st ADT data packet (ADT_PTx(1)), but fails to receive an ACK for it and sends another NACK. When the wireless power receiver responds with an ACK, it confirms that the retransmission of the 1st ADT data packet (ADT_PTx(1)) was successful, and the wireless power transmitter transmits the 2nd ADT data packet (ADT_PTx(2)). After repeating this sequence of ADT packet transmissions, the wireless power transmitter successfully transmits the last remaining 3 bytes, the 24th ADT data packet (ADT_PTx(24)), and then receives an ACK. In response, the wireless power transmitter successfully transmits an EOD and receives an ACK, thereby terminating the transmission of the authentication response message.

[0435] Figure 63 illustrates the exchange sequence of ADT data packets for an authentication response message according to another embodiment. The embodiment in Figure 63 differs from the embodiment in Figure 62 in that the wireless power transmitter divides a total of 99 bytes of the authentication response message into a 4-byte 0th ADT data packet (ADT_PTx(0)), a 4-byte 1st ADT data packet (ADT_PTx(1)), ..., a 4-byte 23rd ADT data packet (ADT_PTx(23)), and a 3-byte 24th ADT data packet (ADT_PTx(24)) and transmits them, while performing simplified synchronization by toggling the header of each ADT data packet according to rule 3 (header A <-> header B), and using the same header used previously (header B in Figure 62) when retransmitting the 1st ADT data packet, thereby instructing retransmission.

[0436] Figure 64 illustrates the exchange sequence of ADT data packets for an authentication response message according to another embodiment. The embodiment in Figure 64 is the same as the embodiment in Figure 63 in that the wireless power transmitter divides the total 99 bytes of the authentication response message into a 4-byte 0th ADT data packet (ADT_PTx(0)), a 4-byte 1st ADT data packet (ADT_PTx(1)), ..., a 4-byte 23rd ADT data packet (ADT_PTx(23)), and a 3-byte 24th ADT data packet (ADT_PTx(24)), and transmits them, with the header of each ADT data packet toggling according to rule 3 (header A <-> header B). However, it differs from the embodiment in Figure 63 in that the wireless power receiver uses GRP to poll the wireless power transmitter, and the transmission of ADT data packets begins when the wireless power transmitter responds with SOD.

[0437] Figure 65 is a diagram illustrating the exchange sequence of ADT data packets for an authentication response message according to another embodiment. The embodiment in Figure 65 differs from the embodiment in Figure 64 in that, when the wireless power transmitter transmits a total of 99 bytes of an authentication response message by dividing it into a 4-byte 0th ADT data packet (ADT_PTx(0)), a 4-byte 1st ADT data packet (ADT_PTx(1)), ..., a 4-byte 23rd ADT data packet (ADT_PTx(23)), and a 3-byte 24th ADT data packet (ADT_PTx(24)), the header is toggled when the transmission of the 1st ADT data packet (ADT_PTx(1)) fails, but a retransmission of the 1st ADT data packet (ADT_PTx(1)) occurs with the header toggled.

[0438] Figure 66 illustrates the exchange sequence of ADT data packets for an authentication response message according to another embodiment. The embodiment in Figure 66 illustrates a scenario in which a wireless power transmitter divides a total of 99 bytes of an authentication response message into a 4-byte 0th ADT data packet (ADT_PTx(0)), a 4-byte 1st ADT data packet (ADT_PTx(1)), ..., a 4-byte 23rd ADT data packet (ADT_PTx(23)), and a 3-byte 24th ADT data packet (ADT_PTx(24)) and transmits them, where the transmission of the 0th ADT data packet (ADT_PTx(0)) is successful, but there is no response to the 1st ADT data packet (ADT_PTx(1)) and the transmission fails.

[0439] 2-2) Authentication of a wireless power receiver by a wireless power transmitter (Authentication of PRx by PTx)

[0440] As a lower-level authentication sequence of the ADT infrastructure, the authentication of a radio power receiver by a radio power transmitter is described (PTx=Initiator / PRx=Responder). When following Rule 1, the radio power transmitter is a slave, so the radio power receiver must provide the radio power transmitter with an ADT once it has confirmed that the radio power transmitter is acting as an authentication initiator based on the AI ​​bit in the radio power transmitter's performance packet.

[0441] Figure 67 illustrates the upper-level and high-level transmission sequences of a wireless power transmitter and a wireless power receiver during ADT data packet exchange according to one embodiment. Here, the wireless power transmitter is the authentication initiator, and the wireless power receiver is the authentication responder. ADT data packet exchange between the wireless power transmitter and receiver is performed by the aforementioned "(1) lower-level authentication sequence" and "(2) lower-level data exchange protocol".

[0442] As shown in Figure 67, the wireless power transmitter pools SODs provided by the wireless power receiver, generates an M-byte CHALLENGE message at the upper level and transmits it to the lower level, which then places it in an ADT data packet (or transport) and transmits it to the wireless power receiver. In this case, the wireless power receiver can repeatedly transmit SODs until the wireless power transmitter responds with an ADT data packet or a timeout occurs.

[0443] According to the lower-level authentication sequence, the ADT data packet relating to the CHALLENGE message may be transmitted in several steps. While the ADT data packet is transmitted in several steps according to rule 2, the radio power receiver transmits an ACK / NACK from the lower level to the radio power transmitter for each subsequent ADT data packet, thereby propagating the ADT data packet to the higher level. After this series of processes, once the transmission of the CHALLENGE message (from the higher level's perspective) or the ADT data packet relating to the CHALLENGE message (from the lower level's perspective) is complete, the radio power transmitter signals the completion of transmission by adding an EOD to the end of the ADT data packet relating to the CHALLENGE message, according to rule 4.

[0444] On the other hand, the wireless power receiver operates as a master according to rule 1, and therefore generates an N-byte CHALLENGE message at the higher level in response to the CHALLENGE_AUTH_RESPONSE message it transmits, without separate pooling, and transmits it to the lower level. The lower level then places this message in an ADT data packet (or transport) and transmits it to the wireless power transmitter.

[0445] According to the lower-level authentication sequence, the ADT data packet relating to the CHALLENGE_AUTH_RESPONSE message may be transmitted in several steps. While the ADT data packet is transmitted in several steps according to rule 2, the radio power transmitter sends an ACK / NACK to the radio power receiver from the lower level for each subsequent ADT data packet, propagating the ADT data packet to the higher level. After this series of processes, once the transmission of the CHALLENGE_AUTH_RESPONSE message (from the higher level's perspective) or the ADT data packet relating to the CHALLENGE_AUTH_RESPONSE message (from the lower level's perspective) is complete, the radio power receiver signals the completion of transmission by adding an EOD to the end of the ADT data packet relating to the CHALLENGE_AUTH_RESPONSE message, according to rule 4.

[0446] Figure 68 illustrates the upper-level and high-level transmission sequences of the wireless power transmitter and wireless power receiver during ADT data packet exchange according to another embodiment.

[0447] The embodiment in Figure 68 differs from the embodiment in Figure 67 in that, while strictly adhering to the addition of SOD and EOD according to Rule 4 each time an ADT data packet is transmitted, the radio power receiver uses a general request packet (GRP) instead of SOD for questioning (or polling) according to Rule 1.

[0448] Figure 69 illustrates the exchange sequence of ADT data packets related to an authentication request message according to one embodiment.

[0449] As shown in Figure 69, once a bitstream (e.g., 35 bytes) for the authentication request message is prepared, the radio power transmitter waits to transmit an ADT data packet from the lower level, consisting of a header (e.g., 1 byte) and a payload (e.g., 34 bytes). Here, the authentication request message could be, for example, a CHALLENGE message.

[0450] At this time, the wireless power receiver performs a pooling operation to check whether or not there is data to be transmitted from the wireless power transmitter. As part of this operation, the wireless power receiver repeatedly transmits SOD until the wireless power transmitter responds or a timeout occurs.

[0451] When SOD gives the radio power transmitter an opportunity to send an authentication request message, the radio power transmitter begins transmitting ADT data packets. When using the PTx→PRx Communication Protocol (FSK), ADT data packets can be up to 4 bytes long, so the 35-byte authentication message is divided and transmitted as a 4-byte 0th ADT data packet (ADT_PRx(0)), a 4-byte 1st ADT data packet (ADT_PTx(1)), ..., a 4-byte 7th ADT data packet (ADT_PTx(7)), and a 3-byte 8th ADT eater packet (ADT_PTx(8)).

[0452] First, the wireless power transmitter successfully transmits the 0th ADT data packet (ADT_PTx(0)) and receives an ACK, but fails to transmit the 1st ADT data packet (ADT_PTx(1)) and receives a NACK. Subsequently, the wireless power transmitter retransmits the 1st ADT data packet (ADT_PTx(1)), but fails to receive an ACK response and sends a NACK. When the wireless power receiver responds with an ACK, it is confirmed that the retransmission of the 1st ADT data packet (ADT_PTx(1)) was successful, and the wireless power transmitter transmits the next 2nd ADT data packet (ADT_PTx(2)). Once all ADT data packets have been transmitted, the wireless power transmitter successfully sends an EOD and receives an ACK, thus ending the transmission of the authentication request message.

[0453] Figure 70 illustrates the exchange sequence of ADT data packets for an authentication request message according to another embodiment. The embodiment in Figure 70 differs from the embodiment in Figure 70 in that the wireless power transmitter divides a total of 35 bytes of an authentication request message into a 4-byte 0th ADT data packet (ADT_PTx(0)), a 4-byte 1st ADT data packet (ADT_PTx(1)), ..., a 4-byte 7th ADT data packet (ADT_PTx(7)), and a 3-byte 8th ADT data packet (ADT_PTx(8)), and transmits them, while performing simplified synchronization by toggling the header of each ADT data packet according to rule 3 (header A <-> header B), and using the same header used previously (header B in Figure 58) when retransmitting an ADT data packet, thereby instructing retransmission.

[0454] Figure 71 illustrates the exchange sequence of ADT data packets for an authentication request message according to another embodiment. The embodiment in Figure 71 is the same as the embodiment in Figure 70 in that the wireless power transmitter divides a total of 35 bytes of an authentication request message into a 4-byte 0th ADT data packet (ADT_PTx(0)), a 4-byte 1st ADT data packet (ADT_PTx(1)), ..., a 4-byte 7th ADT data packet (ADT_PTx(7)), and a 3-byte 8th ADT data packet (ADT_PTx(8)), and transmits them, with the header of each ADT data packet toggling according to rule 3 (header A <-> header B). However, it differs from the embodiment in Figure 70 in that the wireless power receiver uses GRP to poll the wireless power transmitter, and the transmission of ADT data packets begins when the wireless power transmitter responds with SOD.

[0455] Figure 72 illustrates the exchange sequence of ADT data packets for an authentication request message according to another embodiment. The embodiment in Figure 72 differs from the embodiment in Figure 71 in that the wireless power transmitter divides a total of 35 bytes of the authentication request message into a 4-byte 0th ADT data packet (ADT_PTx(0)), a 4-byte 1st ADT data packet (ADT_PTx(1)), ..., a 4-byte 7th ADT data packet (ADT_PTx(7)), and a 3-byte 8th ADT data packet (ADT_PTx(8)), and transmits them, in which the wireless power transmitter obtains an opportunity to transmit the ADT data packets by transmitting RPP in mode 0 and transmitting the RFA bit pattern. It also differs from the embodiment in Figure 71 in that when the transmission of the 1st ADT data packet (ADT_PTx(1)) fails, the header is toggled, even though the header should not be toggled, and retransmission of the 1st ADT data packet (ADT_PTx(1)) occurs with the header toggled.

[0456] Figure 73 illustrates the exchange sequence of ADT data packets for an authentication request message according to another embodiment. The embodiment in Figure 73 describes a scenario in which a wireless power transmitter divides a total of 35 bytes of an authentication request message into a 4-byte 0th ADT data packet (ADT_PTx(0)), a 4-byte 1st ADT data packet (ADT_PTx(1)), ..., a 4-byte 7th ADT data packet (ADT_PTx(7)), and a 3-byte 8th ADT data packet (ADT_PTx(8)) and transmits them, where the transmission of the 0th ADT data packet (ADT_PTx(0)) is successful, but there is no response to the 1st ADT data packet (ADT_PTx(1)), resulting in a transmission failure.

[0457] Figure 74 illustrates the exchange sequence of ADT data packets related to an authentication response message according to one embodiment.

[0458] As shown in Figure 74, once a bitstream (e.g., 99 bytes) for the authentication response message is prepared, the radio power receiver transmits an ADT data packet from the lower level, consisting of a header (e.g., 1 byte) and a payload (e.g., 34 bytes). Here, the authentication response message could be, for example, a CHALLENGE_AUTH_RESPONSE message.

[0459] The wireless power receiver successfully transmits the 0th ADT data packet (ADT_PRx(0)) and receives an ACK. However, the wireless power receiver fails to transmit the 1st ADT data packet (ADT_PRx(1)) and receives a NACK. Subsequently, the wireless power receiver retransmits the 1st ADT data packet (ADT_PRx(1)), but fails to receive an ACK for it and sends another NACK. When the wireless power transmitter responds with an ACK, it confirms that the retransmission of the 1st ADT data packet (ADT_PRx(1)) was successful, and the wireless power receiver transmits the 2nd ADT data packet (ADT_PRx(2)). After repeating this ADT packet transmission sequence, the wireless power transmitter successfully transmits the last remaining ADT data packet (ADT_PRx) and receives an ACK. In response, the wireless power receiver successfully transmits an EOD and receives an ACK, thus ending the transmission of the authentication response message.

[0460] Figure 75 illustrates the exchange sequence of ADT data packets for an authentication response message according to another embodiment. The embodiment in Figure 75 differs from the embodiment in Figure 75 in that the wireless power receiver divides a total of 99 bytes of the authentication response message into a 16-byte 0th ADT data packet (ADT_PRx(0)), a 16-byte 1st ADT data packet (ADT_PRx(1)), ..., a 16-byte 5th ADT data packet (ADT_PRx(5)), and a 3-byte 6th ADT data packet (ADT_PRx(6)), and transmits it, while performing simplified synchronization by toggling the header of each ADT data packet according to rule 3 (header A <-> header B), and using the same header used previously (header B in Figure 75) when retransmitting the 1st ADT data packet, thereby instructing retransmission.

[0461] Figure 76 is a diagram illustrating the exchange sequence of ADT data packets for an authentication response message according to another embodiment. The embodiment in Figure 76 differs from the embodiment in Figure 75 in that, when the wireless power receiver divides and transmits a total of 99 bytes of an authentication response message into a 16-byte 0th ADT data packet (ADT_PRx(0)), a 16-byte 1st ADT data packet (ADT_PRx(1)), ..., a 16-byte 5th ADT data packet (ADT_PRx(5)), and a 3-byte 6th ADT data packet (ADT_PRx(6)), the header is toggled when the transmission of the 1st ADT data packet (ADT_PRx(1)) fails, but a retransmission of the 1st ADT data packet (ADT_PRx(1)) occurs with the header toggled.

[0462] Figure 77 illustrates the exchange sequence of ADT data packets for an authentication response message according to another embodiment. The embodiment in Figure 77 describes a scenario in which a wireless power receiver divides a total of 99 bytes of an authentication response message into a 16-byte 0th ADT data packet (ADT_PRx(0)), a 16-byte 1st ADT data packet (ADT_PRx(1)), ..., a 16-byte 5th ADT data packet (ADT_PRx(5)), and a 3-byte 6th ADT data packet (ADT_PRx(6)) and transmits them, where the transmission of the 0th ADT data packet (ADT_PRx(0)) is successful, but there is no response to the 1st ADT data packet (ADT_PRx(1)), resulting in a transmission failure.

[0463] 2-3) Concurrent Authentication between a wireless power transmitter and a wireless power receiver (PRx and PTx)

[0464] Both the wireless power transmitter and the wireless power receiver can simultaneously operate as authentication initiators.

[0465] As an example, a wireless power transmitter can send an ADT containing authentication-related packets instead of an ADT containing an ACK in response to a packet received from a wireless power receiver. In this case, the wireless power receiver can implicitly consider that it has received an ACK upon receiving the ADT containing authentication-related packets and take the following action: When the wireless power transmitter sends an ADT containing data (authentication-related packets), the wireless power receiver can determine that the ADT data it sent to the wireless power transmitter immediately before was successfully transmitted, even if it receives a data ADT instead of an ACK. However, if a communication error occurred in the ADT data immediately before it was received from the wireless power receiver, the wireless power transmitter can send a NACK. Of course, the ADT containing authentication-related packets may also further include an ACK.

[0466] As another example, a wireless power receiver can send an ADT containing authentication-related packets instead of an ADT containing an ACK in response to packets received from a wireless power transmitter. In this case, the wireless power transmitter can implicitly consider that it has received an ACK by receiving the ADT containing the authentication-related packets and take the following action: When the wireless power receiver sends an ADT containing data (authentication-related packets), the wireless power transmitter can determine that the ADT data it immediately sent to the wireless power receiver was successfully transmitted, even if it receives a data ADT instead of an ACK. Of course, the ADT containing the authentication-related packets may also further include an ACK.

[0467] 2-4) Communication Initiation Protocol by Wireless Power Transmitter

[0468] While the wireless power transmitter operates as a slave under Rule 1, the wireless power receiver can provide opportunities for PTx-initiated communication by performing regular polling. In this case, the initiation of communication by the wireless power transmitter is highly dependent on the wireless power receiver. The wireless power receiver can check whether the wireless power transmitter has packets to transmit by regularly polling it. In this case, a GRP can be used as shown in Figure 78. As shown in Figure 78, for example, the wireless power receiver can perform polling by setting a general request packet to "0xFF", "00", or "FF". If the wireless power transmitter receives a GRP set to "0xFF", "00", or "FF", the wireless power transmitter becomes ready to transmit any type of packet it intends to send.

[0469] On the other hand, as another way to better guarantee the opportunity for communication initiated by the wireless power transmitter, the wireless power transmitter can send a request for communication (RFC) bit pattern as a response to the wireless power receiver's RPP (except mode '100'b). When the wireless power receiver receives the RFC response, it polls the wireless power transmitter using GRP at a time appropriate for it. Even though the wireless power receiver does not know exactly when the target power value managed by the wireless power transmitter changes, the wireless power receiver can relatively well guarantee the communication initiation time desired by the wireless power transmitter through the wireless power transmitter's RFC response.

[0470] In particular, RFC response deadline polling can be used for PTx-initiated power management. PTx-initiated power management allows the PTx to modify (increase or decrease) the target power, taking into account the current ambient charging conditions.

[0471] Figure 79 shows a transmission sequence related to power management initiated by a wireless power transmission device according to one embodiment.

[0472] As shown in Figure 79, the wireless power transmitter sends an alarm containing an RFC response (bit pattern) to the wireless power receiver in response to the RPP (mode 0) from the wireless power receiver. The wireless power receiver sends a GRP with the request value set to "0xFF" to the wireless power transmitter. Subsequently, the wireless power transmitter sends target power packets to the wireless power receiver. The wireless power receiver can adjust its operating mode based on the changed target power.

[0473] 6. Applications related to authentication procedures

[0474] The authentication function can be turned on or off by the user. For example, on a smartphone, an application can display the option to activate or deactivate the authentication function to the user, and the authentication function can be activated or deactivated by the user entering their selection information regarding activation (ON) or deactivation (OFF).

[0475] Wireless power transmitters and receivers can provide a highly convenient user experience and interface (UX / UI). Specifically, smart wireless charging services can be offered, and these services can be implemented based on the UX / UI of a smartphone, including the wireless power transmitter. For such applications, the interface between the smartphone processor and the wireless charging receiver allows for "drop and play" bidirectional communication between the wireless power transmitter and receiver.

[0476] As an example, a user can experience a smart wireless charging service at a hotel. When the user enters a hotel room and places their smartphone on the wireless charger in the room, the wireless charger transmits wireless power to the smartphone, and the smartphone receives the wireless power. During this process, the wireless charger transmits information about the smart wireless charging service to the smartphone. When the smartphone senses that it is positioned on the wireless charger, senses that it has received wireless power, or receives information about the smart wireless charging service from the wireless charger, the smartphone enters a state where it asks the user to consent to additional features (opt-in). For this purpose, the smartphone may display a message on the screen, with or without an alarm sound. An example message may include phrases such as, "Welcome to ### hotel. Select "Yes" to activate smart charging functions: Yes | No Thanks." When the user selects Yes or No Thanks and enters their answer, the smartphone performs the next step selected by the user. If Yes is selected, the smartphone transmits the relevant information to the wireless charger. Then, the smartphone and wireless charger perform the smart charging function.

[0477] Smart wireless charging services can also include receiving Wi-Fi credentials auto-filled. For example, the wireless charger sends Wi-Fi credentials to a smartphone, and the smartphone runs the appropriate app to automatically fill in the Wi-Fi credentials received from the wireless charger.

[0478] The smart wireless charging service may also include running a hotel application that offers hotel promotions, or retrieving remote check-in / check-out and contact information.

[0479] As another example, a user can experience a smart wireless charging service in a vehicle. When a user gets into the vehicle and places their smartphone on a wireless charger, the wireless charger transmits wireless power to the smartphone, and the smartphone receives the wireless power. In this process, the wireless charger transmits information about the smart wireless charging service to the smartphone. When the smartphone senses that it is positioned on the wireless charger, senses that it has received wireless power, or receives information about the smart wireless charging service from the wireless charger, the smartphone enters a state where it prompts the user for identity verification.

[0480] In this state, the smartphone automatically connects to the car via Wi-Fi and / or Bluetooth. The smartphone can display a message on the screen, with or without an alarm sound. An example message might include phrases like, "Welcome to your car. Select "Yes" to synchronize device with in-car controls: Yes | No Thanks." Once the user selects Yes or No Thanks, the smartphone performs the next step selected by the user. If Yes is selected, the smartphone sends the corresponding information to the wireless charger. The smartphone and wireless charger then work together to perform in-car smart control functions by driving the in-car application / display software. The user can enjoy desired music and check their location on a regular map. The in-car application / display software may include the ability to provide synchronized proximity for pedestrians.

[0481] Another example is when a user experiences smart wireless charging in their home. When a user enters a room and places their smartphone on a wireless charger in the room, the wireless charger transmits wireless power to the smartphone, and the smartphone receives the wireless power. In this process, the wireless charger transmits information about the smart wireless charging service to the smartphone. When the smartphone senses that it is positioned on the wireless charger, senses that it has received wireless power, or receives information about the smart wireless charging service from the wireless charger, the smartphone enters a state where it asks the user to consent to additional features (opt-in). For this purpose, the smartphone may display a message on the screen, with or without an alarm sound. An example message may include phrases like, "Hi xxx, Would you like to activate night mode and secure the building? : Yes | No Thanks." When the user selects Yes or No Thanks and enters their answer, the smartphone performs the next step selected by the user. If Yes is selected, the smartphone transmits the corresponding information to the wireless charger. The smartphone and wireless charger can recognize at least the user's patterns and prompt the user to close doors and windows, turn off fires, or set alarms.

[0482] Since not all components or steps are essential in the wireless power transmission method and apparatus, or receiving apparatus and method, according to the embodiments of the present invention described above, the wireless power transmission apparatus and method, or receiving apparatus and method, may include some or all of the components or steps described above. Furthermore, the embodiments of the wireless power transmission apparatus and method, or receiving apparatus and method, described above can be combined with each other. In addition, each component or step described above does not necessarily have to be performed in the order described; a later step may be performed before an earlier step.

[0483] The above description is merely illustrative of the technical concept of the present invention, and a person with ordinary skill in the art to which the present invention belongs can make various modifications and variations as long as they do not deviate from the essential characteristics of the present invention. Therefore, the embodiments of the present invention described above can be realized individually or in combination with each other.

[0484] Accordingly, the embodiments disclosed herein are for illustrative purposes only, and not to limit the technical concept of the present invention, and the scope of the technical concept of the present invention is not limited by such embodiments. The scope of protection of the present invention should be interpreted in accordance with the claims, and all technical ideas within an equivalent scope should be interpreted as being included within the scope of the rights of the present invention.

Claims

1. A wireless power transmission device, A power conversion unit configured to transmit wireless power to a wireless power receiving device, The system includes a communication / control unit configured to control the aforementioned wireless power, The aforementioned wireless power transmission device is Based on the fact that the wireless power transmitter has the data packet to be transmitted, a bit pattern requesting permission for communication is transmitted to the wireless power receiver. After transmitting the bit pattern, the wireless power receiver receives a polling packet from the wireless power transmitter instructing the wireless power transmitter to transmit the data packet. Based on the reception of the polling packet, it is configured to transmit a data stream to the wireless power receiving device. The data stream includes a specific data control packet that identifies the start of the data stream, The data stream includes a sequence of ADT (auxiliary data transport) packets following the specific data control packet in a wireless power transmitter.

2. The wireless power transmitter according to claim 1, wherein the bit pattern is 8 bits.

3. A method for transmitting wireless power to a wireless power receiving device, The aforementioned method, This is done by a wireless power transmission device. The steps include: transmitting a bit pattern requesting permission for communication to the wireless power receiver based on the fact that the wireless power transmitter has the data packet to be transmitted; The steps include receiving a polling packet from the wireless power receiver instructing the wireless power transmitter to transmit the data packet after the transmission of the bit pattern, The step of transmitting a data stream to the wireless power receiving device based on the reception of the polling packet, The data stream includes a specific data control packet that identifies the start of the data stream, The method wherein the data stream includes a sequence of ADT (auxiliary data transport) packets following the specific data control packet.

4. The method according to claim 3, wherein the bit pattern is 8 bits.

5. A wireless power receiving device, A power pickup unit configured to receive wireless power from a wireless power transmitter, The system includes a communication / control unit configured to control the aforementioned wireless power, The aforementioned wireless power receiving device is Based on the fact that the wireless power transmitter has the data packet to be transmitted, a bit pattern requesting permission for communication is received from the wireless power transmitter. After receiving the bit pattern, a polling packet is sent to the wireless power transmitter instructing it to transmit the data packet. Based on the transmission of the polling packet, the system is configured to receive a data stream from the wireless power receiving device. The data stream includes a specific data control packet that identifies the start of the data stream, The data stream includes a sequence of ADT (auxiliary data transport) packets following the specific data control packet in a wireless power receiver.

6. The wireless power receiving device according to claim 5, wherein the bit pattern is 8 bits.

7. A method for receiving wireless power from a wireless power transmitter, The aforementioned method, This is done using a wireless power receiving device. The steps include receiving a bit pattern from the wireless power transmitter requesting permission for communication based on the fact that the wireless power transmitter has the data packet to be transmitted, The steps include: sending a polling packet to the wireless power transmitter instructing it to transmit the data packet after receiving the bit pattern; The step of receiving a data stream from the wireless power receiving device based on the transmission of the polling packet, The data stream includes a specific data control packet that identifies the start of the data stream, The method wherein the data stream includes a sequence of ADT (auxiliary data transport) packets following the specific data control packet.

8. The method according to claim 7, wherein the bit pattern is 8 bits.

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