Apparatus and method for performing 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 power control in a wireless power transmission system. [Background technology]

[0002] Wireless power transmission technology is a technology that wirelessly transmits power between a power source and an electronic device. For example, wireless power transmission technology allows wireless devices such as smartphones and tablets to be charged simply by placing them on a wireless charging pad, thereby providing greater mobility, convenience, and safety than existing wired charging environments that use wired charging connectors. In addition to wireless charging of wireless devices, wireless power transmission technology is gaining attention as an alternative to existing wired power transmission environments in a variety of fields, including electric vehicles, various wearable devices such as Bluetooth earphones and 3D glasses, home appliances, furniture, underground facilities, buildings, medical devices, robots, and leisure activities.

[0003] The wireless power transmission method is also called a contactless power transmission method, a no-point-of-contact power transmission method, or a wireless charging method. A wireless power transmission system includes a wireless power transmitter that supplies electric energy by wireless power transmission, and a wireless power receiver that receives the electric energy wirelessly from the wireless power transmitter and supplies power to a power receiver such as a battery cell.

[0004] There are various wireless power transmission technologies, including those that transmit power through magnetic coupling, radio frequency (RF), microwave, and ultrasonic waves. Magnetic coupling-based methods are further classified into magnetic induction and magnetic resonance. Magnetic induction transmits energy by using a current induced in a receiving coil by a magnetic field generated from a battery cell in the transmitting coil through electromagnetic coupling between the transmitting and receiving coils. Magnetic resonance is similar to magnetic induction in that it uses a magnetic field. However, magnetic resonance differs from magnetic induction in that it transmits energy by generating a magnetic field at both ends of the transmitting and receiving coils, causing resonance when a specific resonant frequency is applied to the transmitting and receiving coils.

[0005] Wireless power systems implemented according to specific standard technologies can pose safety issues when overheating occurs due to foreign objects, etc. However, uncertified products that have not undergone product certification according to technical standards or specifications are distributed in the market, which may expose users to danger. Therefore, it is necessary to ensure stability and reliability by mutually authenticating the wireless power transmitter and the wireless power receiver before and after wireless charging. [Prior art documents] [Patent Documents] [Patent Document 1] JP 2017-229112 A Summary of the Invention [Problem to be solved by the invention]

[0006] SUMMARY OF THE INVENTION A technical object of the present invention 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, there is provided a wireless power transmitting apparatus, including: a power conversion unit configured to transmit wireless power to a wireless power receiving apparatus by forming magnetic coupling with the wireless power receiving apparatus; 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 apparatus.

[0008] Here, the communication / control unit receives a received power packet (RPP) from the wireless power receiving device indicating the power value received by the wireless power receiving device, and if the communication / control unit has data to transmit to the wireless power receiving device, transmits a bit pattern to the wireless power receiving device in response to the RPP requesting communication by the wireless power transmitting device, and receives a packet polling the data to be transmitted from the wireless power receiving device in response to the bit pattern.

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

[0010] In another aspect, the RPP may indicate that the wireless power receiving device is in Mode 0.

[0011] In yet another aspect, if the RPP indicates any mode other than mode 4, the communication / control unit can transmit the bit pattern.

[0012] In yet another aspect, the bit pattern and the polling packet may each be 8 bits.

[0013] According to another aspect of the present invention, there is provided a power control method for a wireless power transmitting apparatus, the method including: transmitting wireless power to a wireless power receiving apparatus by forming magnetic coupling with the wireless power receiving apparatus; and controlling transmission of the wireless power and transmitting or receiving data based on communication with the wireless power receiving apparatus.

[0014] Here, the step of transmitting or receiving data may include the steps of receiving a received power packet (RPP) from the wireless power receiving device, which indicates a power value received by the wireless power receiving device; transmitting a bit pattern to the wireless power receiving device in response to the RPP when the wireless power transmitting device has data to transmit to the wireless power receiving device, which requests communication by the wireless power transmitting device; and receiving a packet from the wireless power receiving device in response to the bit pattern, which polls 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 wireless power.

[0016] In another aspect, the RPP may indicate that the wireless power receiving device is in Mode 0.

[0017] In yet another aspect, if the RPP indicates any mode other than mode 4, the communication / control unit can transmit the bit pattern.

[0018] In yet another aspect, the bit pattern and the polling packet may each be 8 bits.

[0019] According to yet another aspect of the present invention, there is provided a wireless power receiving device, including: a power pickup unit configured to receive wireless power from a wireless power transmitting device by forming magnetic coupling with the wireless power transmitting device; and a communication / control unit configured to control 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 transmits a received power packet (RPP) indicating a 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, receives a bit pattern from the wireless power transmitting device in response to the RPP requesting communication by the wireless power transmitting device, and transmits a packet to the wireless power transmitting device polling the data to be transmitted in response to the bit pattern.

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

[0022] In another aspect, the RPP may indicate that the wireless power receiving device is in Mode 0.

[0023] In yet another aspect, if the RPP indicates a mode other than mode 4, the communication / control unit can receive the bit pattern.

[0024] In yet another aspect, the bit pattern and the polling packet may each be 8 bits.

[0025] According to yet another aspect of the present invention, there is provided a power control method for a wireless power receiving device, the method including: receiving wireless power from a wireless power transmitting device by forming magnetic coupling with the wireless power transmitting device; and controlling transmission of the wireless power and transmitting or receiving data based on communication with the wireless power transmitting device.

[0026] Here, the step of transmitting or receiving data may include the steps of 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 in response to the RPP, when there is data to be transmitted from the wireless power transmitting device to the wireless power receiving device, requesting communication by the wireless power transmitting device, and transmitting a packet to the wireless power transmitting device in response to the bit pattern, polling the data to be transmitted.

[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 yet another aspect, if the RPP indicates a mode other than mode 4, the communication / control unit can receive the bit pattern.

[0030] In yet another aspect, the bit pattern and the polling packet may each be 8 bits. [Effects of the Invention]

[0031] The present invention clearly provides essential elements for authentication between a wireless power transmitting device and a receiving device, such as the format of a wireless charging certificate, instruction information regarding support for authentication functions, 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 drawings]

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

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

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

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

[0036] The wireless power transmitting apparatus 100 generates a magnetic field when power is applied from an external power source S. The wireless power receiving apparatus 200 generates a current using the generated magnetic field and receives power wirelessly.

[0037] In addition, the wireless power transmitting apparatus 100 and the wireless power receiving apparatus 200 in the wireless power system 10 can transmit and receive various information required for wireless power transmission. Here, communication between the wireless power transmitting apparatus 100 and the wireless power receiving apparatus 200 is performed by either in-band communication using a magnetic field used for wireless power transmission or out-band communication using a separate communication carrier.

[0038] Here, the wireless power transmission apparatus 100 may be provided in a fixed or mobile type. Examples of the fixed type include an embedded type in a ceiling, wall, or furniture such as a table indoors, an implant type installed in a parking lot, a bus stop, or a subway station outdoors, or an installed type in a transportation means such as a vehicle or train. The mobile type wireless power transmission apparatus 100 may be implemented as a part of a mobile device having a portable weight and size, or as a part of another device such as a laptop computer cover.

[0039] Furthermore, the wireless power receiving apparatus 200 should be interpreted as a comprehensive concept including various electronic devices equipped with a battery and various home appliances that are powered by wireless power instead of a power cable. Representative examples of the wireless power receiving apparatus 200 include a portable terminal, a cellular phone, a smart phone, a personal digital assistant (PDA), a portable media player (PMP), a Wibro terminal, a tablet, a laptop, a digital camera, a navigation terminal, a television, an electric vehicle (EV), etc.

[0040] The wireless power system 100 may include one or more wireless power receiving devices 200. In Fig. 1, the wireless power transmitting device 100 and the wireless power receiving device 200 are shown exchanging power one-to-one, but as shown in Fig. 2, one wireless power transmitting device 100 may transmit power to multiple wireless power receiving devices 200-1, 200-2, ..., 200-M. In particular, when wireless power transmission is performed using the magnetic resonance method, one wireless power transmitting device 100 may transmit power to multiple wireless power receiving devices 200-1, 200-2, ..., 200-M simultaneously by applying a simultaneous transmission method or a time division transmission method.

[0041] 1 illustrates the wireless power transmitting apparatus 100 directly transmitting power to the wireless power receiving apparatus 200, a separate wireless power transmitting / receiving apparatus such as a relay or repeater for increasing the wireless power transmission distance may be provided between the wireless power transmitting apparatus 100 and the wireless power receiving apparatus 200. In this case, power may be transmitted from the wireless power transmitting apparatus 100 to the wireless power transmitting / receiving apparatus, and the wireless power transmitting / receiving apparatus may transmit power again to the wireless power receiving apparatus 200.

[0042] Hereinafter, the terms "wireless power receiver," "power receiver," and "receiver" referred to in this specification refer to the wireless power receiving device 200. Also, the terms "wireless power transmitter," "power transmitter," and "transmitter" referred to in this specification refer to the wireless power receiving and transmitting device 100.

[0043] FIG. 3 illustrates various embodiments of electronic devices in which the wireless power transmission system may be implemented.

[0044] Figure 3 shows electronic devices classified according to the amount of power transmitted and received by a wireless power transmission system. As shown in Figure 3, a low-power (approximately 5W or less or approximately 20W or less) wireless charging method can be applied to wearable devices such as smart watches, smart glasses, head-mounted displays (HMDs), and smart rings, as well as mobile (or portable) electronic devices such as earphones, remote controls, smartphones, PDAs, and tablet computers.

[0045] A medium-power (approximately 50W or less or approximately 200W or less) wireless charging method can be applied to small and medium-sized home appliances such as laptops, robot vacuum cleaners, TVs, audio equipment, vacuum cleaners, and monitors. A high-power (approximately 2kW or less or approximately 22kW or less) wireless charging method can be applied to kitchen appliances such as blenders, microwave ovens, and electric rice cookers, and personal transportation devices (or electronic devices / transportation means) such as wheelchairs, electric kick scooters, electric bicycles, and electric cars.

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

[0047] Although the following description will be focused on a mobile device to which a wireless power charging method is applied, this is merely an embodiment, and the wireless charging method according to the present invention can be applied to the various electronic devices described above.

[0048] Standards for wireless power transmission include the wireless power consortium (WPC), the air fuel alliance (AFA), and the power matters alliance (PMA).

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

[0050] Each standard covers a variety of wireless power transmitters and receivers using different power levels, and these are classified into different power classes (PCs) or categories.

[0051] For example, the WPC classifies wireless power transmitters and receivers into power classes (PC-1, PC0, PC1, and PC2) and provides standard documents for each PC. The PC-1 standard relates to wireless power transmitters and receivers that provide guaranteed power of less than 5W. PC-1 applications include wearable devices such as smart watches.

[0052] The PC0 standard relates to wireless power transmitters and receivers that provide 5W of guaranteed power. The PC0 standard includes EPP, which provides up to 30W of guaranteed power. In-band (IB) communication is the mandatory communication protocol for PC0, but out-of-band (OBB) communication, used as an optional backup channel, can also be used. A wireless power receiver can identify whether it supports OOB by setting an OOB flag in a configuration packet. A wireless power transmitter that supports OOB can enter the OOB handover phase by transmitting a bit pattern for OOB handover in response to the configuration packet. The response to the configuration packet can be NAK, ND, or a newly defined 8-bit pattern. Applications of PC0 include smartphones.

[0053] The PC1 standard relates to wireless power transmitters and receivers that provide guaranteed power of 30W to 150W. OOB is the required communication channel for PC1, and IB is used for initialization and link establishment to OOB. A 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] As described above, PCs are distinguished by power levels, and whether compatibility between identical PCs is supported is 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, it can be considered that compatibility between identical PCs is 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, it can be considered that compatibility between different PCs is maintained.

[0056] Supporting compatibility between PCs is a very important issue in terms of user experience and infrastructure construction. However, maintaining compatibility between PCs presents various technical challenges, such as the following:

[0057] In the case of compatibility between the same PCs, for example, a laptop-charging type wireless power receiving device that can be stably charged only when power is transmitted continuously may have problems receiving stable power from a power tool-type wireless power transmitting device that transmits power discontinuously, even if the wireless power transmitting device is the same PC. Also, in the case of compatibility between different PCs, for example, if a wireless power transmitting device with a guaranteed power of at least 200 W transmits power to a wireless power receiving device with a maximum guaranteed power of 5 W, the wireless power receiving device may be damaged by overvoltage. As a result, it is difficult to use PCs as an index / standard representing / indicating compatibility.

[0058] Hereinafter, a "profile" is newly defined as an index / criteria representing / indicating compatibility. That is, it can be interpreted that compatibility is maintained between wireless power transceivers having the same "profile" and stable power transmission / reception is possible, while power transmission / reception is impossible between wireless power transceivers having different "profiles." A profile can be defined based on compatibility and / or application, regardless of (or independently of) the power class.

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

[0060] In the case of 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 to 205 kHz. Examples of applications include smartphones and laptops.

[0061] In the case of the "power tool" profile, the PC can be defined as PC1, the communication protocol / method as IB, and the operating frequency as 87 to 145 kHz, and an example of an application is a power tool.

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

[0063] In the case of the "Wearable" profile, the PC can be defined as PC-1, the communication protocol / method as IB, and the operating frequency as 87 to 205 kHz. An example of an application is a wearable device worn on the user's body.

[0064] Maintaining compatibility between the same profiles is mandatory, while maintaining compatibility between other profiles may be optional.

[0065] The above-mentioned 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 / substituted depending on the WPC standard and embodiment.

[0066] When a profile is defined in this way, a wireless power transmitting apparatus selectively transmits power only to a wireless power receiving apparatus having the same profile as itself, enabling more stable power transmission. In addition, the burden on the wireless power transmitting apparatus is reduced, and the wireless power receiving apparatus is prevented from attempting to transmit power to an incompatible wireless power receiving apparatus, thereby reducing the risk of damage to the wireless power receiving apparatus.

[0067] PC1 in the "Mobile" profile can be defined by borrowing a selective extension such as OOB based on PC0, and in the case of the "Power Tool" profile, PC1 "Mobile" profile can be defined as a simply modified version. Also, while previously defined with the aim of maintaining compatibility between the same profiles, in the future, technology may be developed in the direction of maintaining compatibility between different profiles. A wireless power transmitting device or a wireless power receiving device can notify its profile to the other device in various ways.

[0068] The AFA standard refers to a wireless power transmitting device as a PTU (power transmitting unit) and a wireless power receiving device as a PRU (power receiving unit). 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 output power capability of a Class n PTU is TX_IN_MAX A PRU cannot draw more power than specified for that category.

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

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

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

[0075] The primary coil can generate an electromagnetic field using 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, the primary coil can generate a magnetic field of a specific frequency. The magnetic field can be generated in a non-radiative or radiative manner, and the wireless power receiving device 200 receives it and generates a current. In other words, the primary coil transmits power wirelessly.

[0076] In the magnetic induction method, the primary coil and secondary coil may have any suitable form, for example, a copper wire wound around a highly permeable material such as ferrite or amorphous metal. The primary coil may also be called a primary core, primary winding, primary loop antenna, etc. Meanwhile, the secondary coil may also be called a secondary core, secondary winding, secondary loop antenna, pickup antenna, etc.

[0077] When using the magnetic resonance method, the primary coil and the secondary coil are provided in the form of a primary resonant antenna and a secondary resonant antenna, respectively. The resonant antenna may 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 may be formed in the form of a loop. Also, a core may be disposed inside the loop. The core may include a physical core such as a ferrite core or an air core.

[0078] Energy transmission between the primary and secondary resonant antennas can be achieved through magnetic field resonance. Resonance refers to a phenomenon in which, when a near field corresponding to a resonant frequency is generated in one resonant antenna and another resonant antenna is located nearby, the two resonant antennas couple with each other, resulting in highly efficient energy transfer between the resonant antennas. 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 generated by the primary resonant antenna to be focused toward the secondary resonant antenna with higher efficiency than when the magnetic field is generally emitted into free space. Therefore, energy can be transferred from the primary resonant antenna to the secondary resonant antenna with high efficiency. The magnetic induction method is similar 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 spacing between the loops must be very close.

[0079] Although not shown, the wireless power transmission apparatus 1100 may further include a communication antenna. The communication antenna can transmit and receive communication signals using a communication carrier other than magnetic field communication. For example, the communication antenna can transmit and receive communication signals of Wi-Fi, Bluetooth, Bluetooth LE, ZigBee, NFC, etc.

[0080] The communication / control unit 120 can transmit and receive information to and from the wireless power receiving device 200. The communication / control unit 120 can include at least one of an IB communication module or an OOB communication module.

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

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

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

[0084] The communication / control unit 120 can be implemented in a computer or similar device using hardware, software, or a combination thereof. In terms of hardware, the communication / control unit 120 can be implemented in the form of an electronic circuit that processes electrical signals and performs control functions, and in terms of software, the communication / control unit 120 can be implemented 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 an operating point. The controlled operating point may correspond to a combination of a frequency (or phase), a duty cycle, a duty ratio, and a voltage amplitude. The communication / control unit 120 can control the transmission power by adjusting at least one of the frequency (or phase), the duty cycle, the duty ratio, and the voltage amplitude. Alternatively, the wireless power transmitter 100 can supply a constant power, and the wireless power receiver 200 can control the reception power by controlling the resonant frequency.

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

[0087] The wireless power receiving device 200 may include a power pick-up unit 210 and a communications & control unit 220. The power pick-up unit 210 receives wireless power via a secondary coil and converts it into electrical energy. The power pick-up 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 of wireless power (power transmission and reception).

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

[0089] Although not shown in FIG. 4, the communication / control unit 220 may further include a communication antenna. The communication antenna may transmit and receive communication signals using a communication carrier other than magnetic field communication. For example, the communication antenna may transmit and receive communication signals using Wi-Fi, Bluetooth, Bluetooth LE, ZigBee, NFC, etc.

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

[0091] The IB communication module can transmit and receive information using magnetic waves centered on a specific frequency. For example, the communication / control unit 220 can perform IB communication by transmitting information on magnetic waves via a secondary coil or by receiving magnetic waves containing information via a secondary coil. In this case, the communication / control unit 220 can embed information in magnetic waves or analyze magnetic waves containing information using modulation methods such as binary phase shift keying (BPSK) or amplitude shift keying (ASK) and coding methods such as Manchester coding or non-return-to-zero level (NZR-L) coding. Using this IB communication, the communication / control unit 220 can transmit and receive information over distances of up to several meters at a data transmission rate of several kbps.

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

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

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

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

[0096] The load 455 may be a battery. The battery can store energy by using the power output from the power pickup unit 210. However, it is not necessary for the mobile device 450 to include a battery. For example, the battery may be provided as an external, detachable battery. As another example, the wireless power receiving apparatus 200 may include a driving means for driving various operations of the electronic device instead of a battery.

[0097] Although the mobile device 450 is illustrated as including a wireless power receiving device 200 and the base station 400 is illustrated as including a wireless power transmitting device 100, in a broad sense, the wireless power receiving device 200 can be considered the same as the mobile device 450, and the wireless power transmitting device 100 can be considered the same as the base station 400.

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

[0099] FIG. 5 is a state transition diagram for explaining a wireless power transmission procedure.

[0100] As shown in FIG. 5, power transmission from a wireless power transmission device to a receiver according to an embodiment of the present invention can be 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 transition stage (e.g., including reference numerals S502, S504, S508, S510, and S512) to which a transition is made when a specific error or specific event is detected while starting or maintaining power transmission. The specific error and specific event will be clarified in the following description. Furthermore, in the selection phase 510, the wireless power transmission apparatus may monitor whether an object is present on the surface of the interface. If the wireless power transmission apparatus detects an object on the surface of the interface, it may transition to the ping phase 520. In the selection phase 510, the wireless power transmission apparatus may transmit a very short pulse analog ping signal and detect whether an object is present in the active area on the surface of the interface based on a change in current in the transmitting coil or primary coil.

[0102] If an object is detected in the selection phase 510, the wireless power transmitter may measure a quality factor of a wireless power resonant circuit (e.g., a power transmitting coil and / or a resonant capacitor). In an embodiment of the present invention, if an object is detected in the selection phase 510, the quality factor may be measured to determine whether the wireless power receiver is placed with a foreign object in the charging area. The inductance and / or the series resistance component of the coil included in the wireless power transmitter may decrease due to environmental changes, resulting 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 may receive a reference quality factor value measured in advance when no foreign object is present in the charging area from the wireless power receiver. The reference quality factor value received in the negotiation phase S540 may be compared with the measured quality factor value to determine whether a foreign object is present. However, in the case of a wireless power receiving device with a low reference quality factor value (for example, a specific wireless power receiving device may have a low reference quality factor value depending on the type, use, and characteristics of the wireless power receiving device), a problem occurs in that the difference between the measured quality factor value and the reference quality factor value when a foreign object is present is not large, making it difficult to determine whether a foreign object is present. Therefore, other determination factors must be further considered or other methods must be used to determine whether a foreign object 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., an operating frequency range) can be measured to determine whether the wireless power receiving device is placed in the charging area together with a foreign object. The inductance and / or the series resistance component within the coil of the wireless power transmitting device can decrease due to environmental changes, thereby changing (shifting) the resonant frequency of the coil of the wireless power transmitting device. 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, can be shifted.

[0104] In phase 520, when an object is detected, the wireless power transmitter wakes up the receiver and transmits a digital ping to identify whether the detected object is a wireless power receiver. If the wireless power transmitter does not receive a response signal to the digital ping, such as a signal strength packet, from the receiver in the ping phase 520, it transitions back to the selection phase 510. Also, in the ping phase 520, the wireless power transmitter can transition to the selection phase 510 if it receives a signal indicating that power transmission is complete, such as a charging completion packet, from the receiver.

[0105] Once the ping phase 520 is complete, the wireless power transmitter transitions to the identification and configuration phase 530 to identify the receiver and collect configuration and status information of the receiver.

[0106] In the identification and configuration phase 530, the wireless power transmission device can transition to the selection phase 510 if an unexpected packet is received (unexpected packet), if a desired packet is not received for a predefined time (time out), if there is a packet transmission error (transmission error), or if a power transfer contract is not set (no power transfer contract).

[0107] The wireless power transmitting device may determine whether it is necessary to enter the negotiation phase 540 based on a 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 transmitting device may enter the negotiation phase 540 and perform a predetermined FOD detection procedure. On the other hand, if the determination indicates that negotiation is not necessary, the wireless power transmitting device may immediately enter the power transmission phase 560.

[0108] In the negotiation phase 540, the wireless power transmission apparatus may receive a Foreign Object Detection (FOD) status packet including a reference quality factor value. Alternatively, the wireless power transmission apparatus may receive an FOD status packet including a reference peak frequency value. Alternatively, the wireless power transmission apparatus may receive a status packet including a reference quality factor value and a reference peak frequency value. In this case, the wireless power transmission apparatus may determine a quality factor threshold for FOD detection based on the reference quality factor value. Alternatively, the wireless power transmission apparatus may determine a peak frequency threshold for FOD detection based on the reference peak frequency value.

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

[0110] The wireless power transmission device can detect whether an FO exists in the charging area using the 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 an FO is detected, power transmission may be interrupted, but is not limited to this.

[0111] If FOD is detected, the wireless power transmitter may return to the selection phase 510. On the other hand, if FOD is not detected, the wireless power transmitter may go through the correction phase 550 and enter the power transmission phase 560. In particular, if FOD is not detected, the wireless power transmitter may determine the strength of power received at the receiving end in the correction phase 550 and measure the power loss at the receiving end and the transmitting end to determine the strength of power transmitted at the transmitting end. That is, the wireless power transmitter may predict power loss based on the difference between the transmission power of the transmitting end and the reception power of the receiving end in the correction phase 550. According to an embodiment, the wireless power transmitter may correct the threshold for FOD detection to reflect the predicted power loss.

[0112] In the power transmission phase 560, the wireless power transmission device can transition to the selection phase 510 if an unexpected packet is received (unexpected packet), if a desired packet is not received for a predefined time (time out), if a violation of the set power transmission contract occurs (power transfer contract violation), or if charging is completed.

[0113] Furthermore, in the power transmission phase 560, if the power transmission contract needs to be reconfigured due to a change in the state of the wireless power transmission device, the wireless power transmission device may transition to a renegotiation phase 570. At this time, if the renegotiation is successfully completed, the wireless power transmission device may return to the power transmission phase 560.

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

[0115] FIG. 6 illustrates a power control method according to one embodiment.

[0116] 6, in the power transmission phase 560, the wireless power transmitting apparatus 100 and the wireless power receiving apparatus 200 can control the amount of power transmitted by communicating in parallel with power transmission and reception. The wireless power transmitting apparatus and the wireless power receiving apparatus operate at a specific control point. The control point indicates the combination of voltage and current provided at the output of the wireless power receiving apparatus when power transmission is performed.

[0117] More specifically, the wireless power receiving device selects a desired control point (e.g., a desired output current / voltage, a temperature at a specific location of the mobile device, etc.), and then determines an actual control point where the wireless power receiving device is currently operating. The wireless power receiving device can calculate a control error value using the desired control point and the actual control point, and transmit the calculated control error value to the wireless power transmitting device as a control error packet.

[0118] The wireless power transmitter can then control power transfer by setting / controlling new operating points (amplitude, frequency, and duty cycle) using the received control error packet. Therefore, the control error packet is transmitted / received at regular time intervals during the power transfer phase. In one embodiment, the wireless power receiver can transmit a control error value set to a negative value when attempting to reduce the current of the wireless power transmitter, or a positive value when attempting to increase the current. In this way, in the induction mode, the wireless power receiver can control power transfer by transmitting a control error packet to the wireless power transmitter.

[0119] The resonant mode, described below, can operate in a different manner from the inductive mode. In the resonant mode, one wireless power transmitter must be able to simultaneously serve multiple wireless power receivers. However, when controlling power transmission as in the inductive mode, the transmitted power is controlled through communication with one wireless power receiver, which can make it difficult to control power transmission to additional wireless power receivers. Therefore, in the resonant mode of the present invention, the wireless power transmitters transmit a common base power, and the wireless power receivers control the amount of power they receive by controlling their own resonant frequencies. However, the method described in FIG. 6 does not completely exclude the operation in the resonant mode, and additional transmission power control can also be performed using the method described in FIG. 6.

[0120] 7 is a block diagram of a wireless power transmission device according to another embodiment. This may belong to a wireless power transmission system of a magnetic resonance type or a shared mode. The shared mode refers to a mode in which one-to-multiple communication and charging are performed between a wireless power transmission device and a wireless power receiving device. The shared mode is realized by a magnetic induction type or a resonance type.

[0121] 7, the wireless power transmitting device 700 may include at least one of a cover 720 covering a coil assembly, a power adapter 730 supplying power to a power transmitting unit 740, the 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 optionally included or may be included as another user interface 750 of the wireless power transmitting device 700.

[0122] The power transmitter 740 may include at least one of 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 may also be referred to as 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 a resonance at a suitable frequency to boost the primary coil current. In a multi-coil power transmitter 740, the impedance matching circuit can also include a multi-flex that routes signals from the inverter to a subset of the primary coils. The impedance matching circuit can also be referred to as 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 may be performed by detecting a reflected wave of wireless power transmitted through the coil assembly 760 and switching the switching element based on the detected reflected wave to adjust the connection state of the capacitor or inductor, adjust the capacitance of the capacitor, or adjust the inductance of the inductor. In some cases, the impedance matching circuit 770 may be omitted, and this specification also includes an embodiment of the wireless power transmission apparatus 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 a pulse wave with an adjustable frequency and duty cycle. The inverter can 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 monitor the amplitude and / or phase of the current and / or voltage in the primary coil to demodulate the data transmitted by the power receiver using the communication unit 790.

[0128] The power transmitter 740 can also control the output power to transmit data via the communication unit 790 using a frequency shift keying (FSK) method or the like.

[0129] The control unit 710 can control communication and power transfer of the power transmitter 740. The control unit 710 can control power transmission by adjusting the aforementioned operating point, which 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 may be provided as one unit / element / chipset.

[0131] 8 shows a wireless power receiving device according to another embodiment, which belongs to a magnetic resonance type or shared mode wireless power transmitting system.

[0132] 8, the wireless power receiving device 800 may include at least one of a user interface 820 that provides power transfer 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 the coil assembly. In particular, the user interface 820 may be optionally included or may be included as another user interface 82 of the power receiving device.

[0133] The power receiver 830 may include at least one of 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 wireless power and convert it from AC to DC. The rectifier can convert AC to DC using a diode or transistor and smooth it using a capacitor and resistor. The rectifier can be a full-wave rectifier, a half-wave rectifier, a voltage multiplier, or the like, realized by a bridge circuit or the like. Furthermore, the power converter can adapt the reflected impedance of the power receiver.

[0135] The impedance matching circuit 870 may provide impedance matching between the combination of the power converter 860 and the load circuit 870 and the secondary coil. In an embodiment, the impedance matching circuit may generate a resonance around 100 kHz, which can enhance power transfer. The impedance matching circuit 870 may be configured with a capacitor, an inductor, and a switching element that switches a combination of these. Impedance matching may be performed by controlling the switching elements of the circuit that constitutes the impedance matching circuit 870 based on the voltage value, current value, power value, frequency value, etc. of the received wireless power. In some cases, the impedance matching circuit 870 may be omitted, and this specification also includes an embodiment of the wireless power receiving apparatus 200 in which the impedance matching circuit 870 is omitted.

[0136] The coil assembly 880 includes at least one secondary coil and may optionally further include elements to shield metallic portions of the receiver from magnetic fields.

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

[0138] To this end, the power receiver 830 may also switch in resistors or capacitors to change the reflected 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 of the power receiver 830 and the desired operating point. The control unit 810 then adjusts / reduces the difference between the actual operating point and the desired operating point by adjusting the reflected impedance of the power transmitter and / or requesting an adjustment of the operating point of the power transmitter. When this difference is minimized, optimal power reception can be achieved.

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

[0141] Figure 9 shows a communication frame structure according to one embodiment, which may be a communication frame structure in shared mode.

[0142] 9, different types of frames can be used together in the shared mode. For example, in the shared mode, a slotted frame having multiple slots as shown in (A) and a free format frame without a specific format as shown in (B) can be used. More specifically, the slotted frame is a frame for transmitting a short data packet from the wireless power receiving apparatus 200 to the wireless power transmitting apparatus 100, and the free format frame does not have multiple slots and can therefore transmit a long data packet.

[0143] Meanwhile, the slot frame and the free format frame may be renamed to various names by those skilled in the art. For example, the slot frame may be renamed to a channel frame, and the free format frame may be renamed to a message frame.

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

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

[0146] A sync pattern may be located between each two consecutive slots among the nine slots, in which case the sync pattern provides information about the two consecutive slots.

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

[0148] On the other hand, the free format frame as shown in (B) may not have a specific form other than a sync pattern indicating the start of the frame and a measurement slot. That is, the free format frame is intended to perform a different role from the slot frame, for example, to communicate a long data packet (e.g., an additional owner information packet) between the wireless power transmitter and the wireless power receiver, or to select one of multiple coils in a wireless power transmitter configured with multiple coils.

[0149] Hereinafter, the sync pattern included in each frame will be described in more detail with reference to the drawings.

[0150] FIG. 10 is a structure of a sync pattern according to one embodiment.

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

[0152] More specifically, the preamble is composed of consecutive bits, all of which may be set to 0. That is, the preamble is a bit for adjusting the time length of the sync pattern.

[0153] The number of bits constituting the preamble can be dependent on the operating frequency so that the length of the sync pattern is closest to, but not exceeding, 50 ms. For example, if the operating frequency is 100 kHz, the sync pattern will consist of two preamble bits, and if the operating frequency is 105 kHz, the sync pattern will consist of three preamble bits.

[0154] The start bit is the bit following the preamble and means zero. The zero may be a bit indicating the type of sync pattern. Here, the types of sync patterns include a frame sync containing information about a frame and a slot sync containing information about a slot. 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 constituting a frame and containing information about the consecutive slots.

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

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

[0157] The response field may contain response information of the wireless power transmitting device in response to communication with the wireless power receiving device in a slot before the sync pattern. For example, the response field may contain "00" if no communication with the wireless power receiving device is detected. The response field may also contain "01" if a communication error is detected in communication with the wireless power receiving device. The communication error may occur when two or more wireless power receiving devices attempt to access one slot and a collision occurs between the two or more wireless power receiving devices.

[0158] The response field may include information indicating whether the data packet has been correctly received from the wireless power receiving apparatus. More specifically, the response field may be set to “10” (10-not acknowledge, NAK) if the wireless power transmitting apparatus denies the data packet, or “11” (11-acknowledge, ACK) if the wireless power transmitting apparatus confirms the data packet.

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

[0160] Additionally, the type field may have a "0" to indicate that the sync pattern is a slot sync if it is not the first sync pattern in the slot frame.

[0161] Furthermore, the meaning of the value of the information field is determined by the type of sync pattern indicated by the type field. For example, if the type field is 1 (i.e., indicates frame sync), 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] Alternatively, if the type field is 0 (i.e., slot sync), the information field may indicate the status of the next slot located after the sync pattern. More specifically, the information field may have '00' if the next slot is allocated to a specific wireless power receiving device, '01' if the slot is locked for temporary use by a specific wireless power receiving device, or '10' if the slot is freely available to any wireless power receiving device.

[0163] FIG. 11 illustrates an operation state of a wireless power transmitter and a wireless power receiver in a shared mode according to an embodiment.

[0164] As shown in FIG. 11, a wireless power receiving device operating in a shared mode can operate in any one of a selection phase 1100, an introduction phase 1110, a configuration phase 1120, a negotiation phase 1130, and a power transfer phase 1140.

[0165] First, a wireless power transmitter according to an embodiment may transmit a wireless power signal to detect a wireless power receiver. That is, a process of detecting a wireless power receiver using a wireless power signal may be called analog ping.

[0166] Meanwhile, a wireless power receiving device that has received a wireless power signal may enter a selection phase 1100. The wireless power receiving device that has entered the selection phase 1100 may detect the presence of an FSK signal in the wireless power signal, as described above.

[0167] That is, the wireless power receiving device can perform communication in either the exclusive mode or the shared mode depending on whether or not an FSK signal is present.

[0168] More specifically, the wireless power receiving device can operate in a shared mode if the wireless power signal includes an FSK signal, and can operate in an exclusive mode if the wireless power signal does not include an FSK signal.

[0169] When the wireless power receiving device operates in a shared mode, the wireless power receiving device may enter an introduction phase 1110. In the introduction phase 1110, the wireless power receiving device may transmit a control information (CI) packet to the wireless power transmitting device to transmit the control information packet in the configuration 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 the introduction phase 1110, the wireless power receiving device attempts to request a free slot to transmit a control information (CI) packet during the following configuration phase, negotiation phase, and power transmission phase. At this time, the wireless power receiving device selects a free slot and transmits the first CI packet. If the wireless power transmitting device responds to the CI packet with an ACK, the wireless power transmitting device enters the configuration phase. If the wireless power transmitting device responds with a NACK, it means that another wireless power receiving device is in the configuration and negotiation phases. In this case, the wireless power receiving device attempts to request a free slot again.

[0171] If the wireless power receiving device receives an ACK in response to the CI packet, the wireless power receiving device determines the location of a private slot in the frame by counting the remaining slot syncs up to the first frame sync, and in all subsequent slot-based frames, the wireless power receiving device transmits a CI packet through that slot.

[0172] If the wireless power transmitting device allows the wireless power receiving device to proceed to the configuration phase, the wireless power transmitting device provides a series of locked slots for the exclusive use of the wireless power receiving device, which ensures that the wireless power receiving device proceeds to the configuration phase without collision.

[0173] The wireless power receiving device transmits a sequence of data packets, such as two identification data packets (IDHI and IDLO), using the lock slot. Upon completing this phase, the wireless power receiving device enters the negotiation phase. In the negotiation phase, the wireless power transmitting device continuously provides the wireless power receiving device with lock slots for exclusive use. This ensures that the wireless power receiving device proceeds through the negotiation phase without collisions.

[0174] The wireless power receiving device uses the lock slot to transmit one or more negotiation data packets, which may be intermixed with proprietary data packets. Eventually, the sequence ends with a specific request (SRQ) packet. Upon completing the sequence, the wireless power receiving device enters the power transmission phase, and the wireless power transmitting device ceases providing the lock slot.

[0175] In the power transmission state, the wireless power receiving device transmits a CI packet using the assigned slot to receive power. The wireless power receiving device may include a regulator circuit. The regulator circuit may be included in the communication / control unit. The wireless power receiving device can self-regulate its reflected impedance via the regulator circuit. In other words, the wireless power receiving device can adjust the reflected impedance 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 power in response to received CI packets (depending on the operating mode), in which case control is needed to prevent overvoltage conditions.

[0177] The following describes authentication between a wireless power transmitter and a wireless power receiver. Wireless power transmitters and wireless power receivers can be compatible and power can be transferred normally only if they have the same pre-defined power transmission and communication interfaces. Even if a wireless power transmitter and a wireless power receiver are not manufactured by the same manufacturer, they can be compatible if they are manufactured according to the same technical standard. However, even if they comply with the same technical standard, the quality of the products varies from manufacturer to manufacturer, and failure to faithfully and accurately comply with the standard can limit wireless charging. In particular, products with poor foreign object detection (FOD) and overheating prevention functions pose a risk of safety hazards, such as explosions. Therefore, standardization organizations that manage technical standards provide services to certify the authenticity of each manufacturer's wireless power transmitter or wireless power receiver by using authorized certification agencies to test whether the manufacturer's wireless power transmitter or wireless power receiver complies with the standard and ensures interoperability.

[0178] However, since it is practically difficult to completely block uncertified products from circulating in the market, it is necessary to ensure stability and reliability by mutually authenticating wireless power transmitters and wireless power receivers already on the market to ensure their mutual normality before and after wireless charging. In other words, a pre-authentication procedure is when a recognized certification body certifies a product before its release, while a post-authentication procedure is when an authentication procedure is performed between products during the wireless charging operation after the product is released. For example, mutual authentication between products can be performed via an in-band communication channel and is compatible with USB-C authentication. If authentication fails, the wireless power receiver can warn the user and charge in low power mode or remove the power signal.

[0179] In this specification, the WPC Qi standard is exemplified as the standard technology, but the technical idea of ​​the present invention includes not only the Qi standard but also embodiments of certification based on other standards.

[0180] In introducing USB-C certification to wireless power transmission systems using in-band communication, the performance indicators shown in the following table are derived, which means that USB-C will become a model for wireless charging certification.

[0181] [Table 3]

[0182] In Table 3, PRx means a wireless power receiving device, and PTx means a wireless power transmitting device. Authentication includes authentication of the wireless power transmitting device by the wireless power receiving device, and authentication of the wireless power receiving device by the wireless power transmitting device.

[0183] Authenticating a wireless power transmission device using full authentication can take as long as three minutes. This is due to the large size of the USB-C certificate and the low-bit-rate communication protocol used by wireless power transmission systems. In particular, in public venues where users frequently change wireless charging spots, requiring full authentication every time can be inconvenient for users. Therefore, it is necessary to define a compact or simplified size for the authentication-related chain or packet. Of course, it is preferable to reduce the full authentication time to a reasonable time (within 60 seconds) while maintaining the 128-bit security level (ECDSA with SHA256) of USB-C authentication. Of course, the authentication time may increase due to repeated data transmissions caused by traffic errors.

[0184] Specific embodiments of the certificates, authentication procedures, authentication messages, and lower-level communication protocols used in standard authentication techniques are disclosed below. All authentication-related communications, protocols, messages, packets, etc. described below can be generated, processed, stored, transmitted, and manipulated by the communication and control units 120, 220 and communication units 790, 890 described herein.

[0185] 1. Wireless charging certificate

[0186] The certificate chain level aspect may limit the level of a certificate chain. For example, the certificate chain level may be 3. Operating at a minimum chain level still allows manufacturers to issue their own certificates for products, reducing the burden on manufacturers and certificate authorities (CAs). A certificate chain is a series of two or more certificates, each signed by the preceding certificate in the chain.

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

[0188] Regarding the certificate format, the certificate format may be specified as a reduced or simplified format. Here, the "reduced" or "simplified" format may refer to 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 smaller than 100 bytes (e.g., 80 bytes). In this case, the root certificate may still follow the USB-C certificate format. Hereinafter, the simplified certificate format may be referred to as the wireless charging certificate format or the Qi certificate format. It goes without saying that a wireless power transmission system that supports out-of-band (OOB) communication, such as PC1, can provide a wireless charging certificate in the USB-C format because it can use a wider bandwidth.

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

[0190] As shown in FIG. 12, the wireless charging certificate format includes a certificate type, a certificate length, an identification (ID), a reserved bit, a public key, and a signature.

[0191] The certificate type is, for example, one byte and can indicate that the corresponding certificate is one of a root certificate, an intermediate certificate, or a leaf certificate, or that the corresponding certificate is a certificate related to a wireless power transmission device or a certificate related to a wireless power receiving device, or can indicate both of these types of information. For example, when the bit string b3 to b0 of the certificate type is '0000'b, it indicates an intermediate certificate, and when it is '0001'b, it indicates a leaf certificate. When the bit string b7 to b4 of the certificate type is '0001'b, it indicates a certificate related to a wireless power transmission device, and when it is '0000'b, it indicates a certificate related to a wireless power receiving device. Therefore, when the bit string of the certificate type is a certain value, it can indicate that the corresponding certificate is related to a wireless power transmission device and a leaf certificate.

[0192] The length of the 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 code of the wireless power transmitting device or the manufacturer code of the wireless power receiving device, or may indicate a WPID (wireless power ID).

[0194] The reserved 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 through in-band communication based on the wireless charging certificate format shown in FIG. 12, full authentication between the devices can be completed within one minute as shown in Table 4.

[0196] [Table 4]

[0197] FIG. 12 illustrates an example in which the certificate format size is 80 bytes, but this is merely an example, and an embodiment in which each field is defined as a different number of bits is also obvious to those skilled in the art and falls within the technical concept of the present invention.

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

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

[0200] In the wireless charging certificate format of FIG. 13A, the PTx and leaf indicator are separated from the certificate type and are assigned to different bits from the certificate type within the same byte (B0).

[0201] The certificate type may be, for example, 6 bits, and may indicate that the certificate is one of a root certificate, intermediate certificate, or leaf certificate, or may indicate that the certificate is a certificate related to a wireless power transmitting device or a certificate related to a wireless power receiving device, or may indicate both types of information.

[0202] The PTx and leaf indicator indicate whether the corresponding certificate is related to the wireless power transmission apparatus and whether it is a leaf certificate. That is, the PTx and leaf indicator can indicate whether the corresponding certificate is a leaf certificate related to the wireless power transmission apparatus.

[0203] The PTx and leaf indicators are, for example, 2 bits, and are configured in a form including a 1-bit PTx indicator and a 1-bit leaf indicator. In this case, the PTx indicator indicates 1 if the corresponding certificate is related to a wireless power transmitting apparatus, and indicates 0 if the corresponding certificate is related to a wireless power receiving apparatus. Also, the leaf indicator is 1 bit, and the value is set to 1 if the corresponding certificate is a leaf certificate, and the value is set to 0 if the corresponding certificate is not a leaf certificate. In Figure 13A, each bit is set to 1, indicating that the corresponding certificate is a PTx leaf certificate.

[0204] The PTx and leaf indicator are included in the same byte (B0) as the certificate type, are configured in the bit string immediately adjacent to the certificate type, and are assigned to bits different from the certificate type.

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

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

[0207] The reserved bits may be, for example, 4 bytes, the public key may be, for example, 32 bytes, and the signature may be, for example, 64 bytes.

[0208] When authentication is performed through in-band communication based on the same wireless charging certificate format as shown in FIG. 13A, full authentication between the devices can be completed within 60 seconds as shown in Table 5.

[0209] [Table 5]

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

[0211] As a commercial performance requirement, the authentication procedure should complete authentication of a responder by an initiator within 60 seconds using in-band communications, and should provide a mechanism for secure recognition of a previously authenticated responder within 20 seconds using in-band communications.

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

[0213] As shown in FIG. 13B, the wireless charging certificate format includes a wireless charging standard certificate structure version (Qi Authentication Certificate Structure Version), a reserved bit, a PTx and leaf indicator (PTx Leaf), a certificate type, a signature offset, a serial number, an issuer ID, a subject ID, a public key, and a signature.

[0214] In the wireless charging certificate format, the PTx and leaf indicator are separated from the certificate type and assigned to different bits from the certificate type within the same byte (B0).

[0215] The PTx and leaf indicator indicate whether the corresponding certificate is related to the wireless power transmission apparatus and whether it is a leaf certificate. That is, the PTx and leaf indicator can indicate whether the corresponding certificate is a leaf certificate related to the wireless power transmission apparatus.

[0216] PTx and leaf indicator may be 1 bit, unlike in Fig. 13A. When PTx and leaf indicator are 0, this indicates that the corresponding certificate is not a leaf certificate or that it is a leaf certificate of a wireless power receiving device. On the other hand, when PTx and leaf indicator are 1, this indicates that the corresponding certificate is a leaf certificate of a wireless power transmitting device.

[0217] The certificate type is, for example, a 2-bit value, and can indicate that the corresponding certificate is one of a root certificate, an intermediate certificate, or a leaf certificate, or can indicate all of them.

[0218] 2. Instructions for supporting authentication features

[0219] If either the wireless power transmitter or the wireless power receiver does not support the authentication function (e.g., a legacy product that has already been released may not support the new authentication function), the authentication procedure cannot be performed between them. That is, for the authentication procedure to be performed, both the wireless power transmitter and the wireless power receiver must support the authentication function. However, since the authentication function may or may not be supported by the manufacturer depending on the product version, a procedure to confirm this and the messages used in this procedure are required. Furthermore, if only one of the wireless power transmitter and the receiver supports the authentication function and the other is a legacy product, backward compatibility for the minimum charging function must be satisfied. According to system policy, even devices that do not support authentication must support 5W (or a lower minimum power, e.g., 3W).

[0220] A wireless power transmitter can inform a wireless power receiver whether it supports an authentication function using a capability packet (in the case of authentication of a wireless power transmitter by a wireless power receiver (authentication of PTx by PRx)). Meanwhile, a wireless power receiver can inform a wireless power transmitter whether it supports an authentication function using a configuration packet (in the case of authentication of a wireless power receiver by a wireless power transmitter (authentication of PRx by PTx)). The structure of the indication information (capability packet and configuration packet) regarding whether the authentication function is supported will be disclosed in more detail below.

[0221] FIG. 14 shows the structure of a performance packet of a wireless power transmitter according to one embodiment.

[0222] 14, a performance packet whose corresponding header value is 0X31 has three bytes, where the first byte (B0) includes a power class and a guaranteed power value, the second byte (B1) includes reserved and a potential power value, and the third byte (B2) includes reserved, authentication (Auth), NFCPP, NFCD, WPID, and Not REs Sens. Specifically, authentication (Auth) is 1 bit, and for example, a value of 0 indicates that the wireless power transmission apparatus does not support the authentication function, and a value of 1 indicates that the wireless power transmission apparatus supports the authentication function.

[0223] FIG. 15 shows a structure of a performance packet of a wireless power transmission device according to another embodiment.

[0224] 15, a performance packet having a corresponding header value of 0X31 has three bytes, where the first byte (B0) includes a power class and a guaranteed power value, the second byte (B1) includes a reserved and a potential power value, and the third byte (B2) includes an authentication initiator (AI), an authentication responder (AR), reserved, WPID, and Not REs Sens. Specifically, the authentication initiator is a 1-bit value, and if its value is '1b', it indicates that the wireless power transmission apparatus can operate as an authentication initiator. Also, the authentication responder is a 1-bit value, and if its value is '1b', it indicates that the wireless power transmission apparatus can operate as an authentication responder.

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

[0226] 16, a configuration packet having a corresponding header value of 0X51 has five bytes, where the first byte (B0) includes a power class and a maximum power value, the second byte (B1) includes reserved, the third byte (B2) includes Prop, reserved, ZERO, and Count, the fourth byte (B3) includes a window size and a window offset, and the fifth byte (B4) includes Neg, polarity, depth, authentication (Auth), and reserved. Specifically, authentication (Auth) is a 1-bit value, and for example, a value of 0 indicates that the wireless power receiving apparatus does not support the authentication function, and a value of 1 indicates that the wireless power receiving apparatus supports the authentication function.

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

[0228] 17, a configuration packet having a corresponding header value of 0X51 has five bytes, where the first byte (B0) includes a power class and a maximum power value, the second byte (B1) includes AI, AR, and Reserved, the third byte (B2) includes Prop, Reserved, ZERO, and Count, the fourth byte (B3) includes a window size and a window offset, and the fifth byte (B4) includes Neg, Polarity, Depth, Authentication (Auth), and Reserved. Specifically, the authentication initiator is 1 bit, and if its value is '1'b, for example, it indicates that the wireless power receiving apparatus can operate as an authentication initiator. Also, the authentication responder is 1 bit, and if its value is '1b', for example, it indicates that the wireless power receiving apparatus can operate as an authentication responder.

[0229] 3. Timing between authentication-related steps and wireless charging phases

[0230] The procedure for checking whether the authentication function is supported and the authentication procedure can be performed over at least one or more phases of an identification and configuration phase, a negotiation phase, a calibration phase, a power transmission phase, a renegotiation phase, and an introduction phase.

[0231] For example, the authentication procedure may be performed in the negotiation phase. However, when quick authentication is performed in the negotiation phase, the process of reading and checking DIGESTS through in-band communication may take approximately 4 seconds. Therefore, in terms of user convenience, rather than starting charging after authentication is complete, it may be considered to provide wireless charging at basic power even before authentication, regardless of whether authentication is performed. This is also preferable in terms of backward compatibility with devices without authentication functions.

[0232] As another example, the authentication procedure may be performed over the negotiation phase and the power transmission phase. During the identification and configuration phase, packet sequences are strictly controlled, allowing only unidirectional communication from the wireless power receiving device to the transmitting device, whereas during the negotiation and power transmission phase, bidirectional communication is permitted. Therefore, the authentication procedure may be performed during the negotiation and power transmission phases, where bidirectional communication is permitted. During the negotiation phase, quick authentication is performed by the wireless power transmitting device or the receiving device exchanging {GET_DIGESTS, CHALLENGE} messages. A power contract may then be concluded based on the established trust. When the wireless power transmitting device and the receiving device first meet each other by checking DIGESTS, they establish an initial power contract based on system policy and enter the power transmission phase to provide the wireless power receiving device with default low power as quickly as possible. During the power transmission phase, full authentication is performed by the wireless power transmitting device or the receiving device exchanging {GET_CERTIFICATE, CHALLENGE} messages. Once full authentication is successfully completed, the wireless power transmitting device and / or receiving device renews the power contract.

[0233] As another example, the wireless power transmitter and receiver may immediately enter the power transmission phase without authentication and then perform an authentication procedure in the power transmission phase. If authentication is successful in the power transmission phase, the power contract may be renewed through a renegotiation phase, or the wireless power transmitter / receiver may support a target power or full power that it can support at a desired level. This increases user convenience.

[0234] As another example, in the case of authentication of a wireless power transmitter by a wireless power receiver (PTx by PRx), the wireless power receiver may perform a procedure to check whether the wireless power transmitter supports the authentication function in the negotiation phase. In this case, power transmission may already be in progress based on an initial power contract before the negotiation phase. In the negotiation phase, the wireless power receiver may transmit a query packet and check the response to the query packet to check whether the wireless power transmitter supports the authentication function according to the procedure. In one aspect, the query packet may 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 15 to the wireless power receiver as a response. In another aspect, the query packet may be a specific request packet (0x20). In this case, when the wireless power receiving apparatus transmits the specific request packet to the wireless power transmitting apparatus, the wireless power transmitting apparatus responds with an ACK (if it supports the authentication function) or a NACK (if it does not support the authentication function). If it is confirmed in the negotiation phase that the wireless power transmitting apparatus supports the authentication function, the wireless power receiving apparatus can establish a power contract of 5 W or more with the wireless power transmitting apparatus (PC0).

[0235] The authentication procedure can be initiated only when the wireless power receiving device confirms that the wireless power transmitting device supports the authentication function. More specifically, the wireless power receiving device can perform the authentication procedure with the wireless power transmitting device after reaching a normal or stable operation point in which the wireless power receiving device transmits a control error packet (CEP) at a period of approximately 250 ms. During the power transmission phase, the authentication procedure can be used to renew an existing power contract. That is, the wireless power receiving device can renegotiate the power contract to increase the power level under the existing power contract depending on the result of the authentication procedure. In this case, the wireless power receiving device can renew the power contract according to the power management policy by sending a renegotiation packet (0x09). For example, if the authentication procedure (with DIGEST) is successful, the wireless power receiving device can renew the power contract to an increased power or maintain the current power contract. On the other hand, if the authentication procedure fails, the wireless power receiving device can renew the power contract to a decreased power or remove the power signal.

[0236] As another example, in the case of authentication of a wireless power receiving device by a wireless power transmitting device (authentication of PRx by PTx), the wireless power transmitting device may perform a procedure of checking whether the wireless power receiving device supports an authentication function in an initialization phase. Here, the initialization phase may be any one of a selection phase, a ping phase, and an identification and configuration phase before the negotiation phase. In the initialization phase, the wireless power transmitting device receives a configuration packet including authentication (auth) as shown in FIG. 16 or 17 from the wireless power receiving device to check whether the wireless power receiving device supports the authentication function.

[0237] If the wireless power transmitter confirms that the wireless power receiver supports the authentication function, an authentication procedure can be initiated in the negotiation phase. At this time, an initial power contract is concluded. More specifically, the wireless power transmitter waits to receive a DIGESTS from the wireless power receiver. If the wireless power transmitter acknowledges that the wireless power receiver has been previously authenticated, the authentication procedure is successful. If the wireless power transmitter fails to acknowledge 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 time, the wireless power transmitter can establish a power contract of 5 W or more with the wireless power receiver (PC0) that has passed the authentication as DIGESTS. Once 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 receiving device reaches a normal or stable operation point during the power transmission phase, in which the wireless power receiving device transmits a control error packet (CEP, 0x03) at a period of approximately 250 ms, the wireless power transmitting device can perform an authentication procedure with the wireless power receiving device. During the power transmission phase, the authentication procedure can be used to renew an existing power contract. That is, the wireless power receiving device can renegotiate the power contract to increase the power level under the existing power contract depending on the result of the authentication procedure. In this case, the wireless power receiving device can renew the power contract according to the power management policy by sending a renegotiation packet (0x09). For example, if the authentication procedure (with DIGEST) is successful, the wireless power receiving device can renew the power contract to an increased power or maintain the current power contract. On the other hand, if the authentication procedure fails, the wireless power receiving device can renew the power contract to a decreased power or remove the power signal.

[0239] 4. Authentication Procedures and Messages

[0240] In the following, an authentication procedure and various messages used in the authentication procedure are disclosed.

[0241] A message used in the authentication procedure is called an authentication message. The authentication message is 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. The authentication request is sent by an authentication initiator, and the authentication response is sent by an authentication responder. Both the wireless power transmitting device and the receiving device can be the authentication initiator and the authentication responder. For example, if the wireless power transmitting device is the authentication initiator, the wireless power receiving device is the authentication responder, and if the wireless power receiving device is the authentication initiator, the wireless power transmitting device is the authentication responder.

[0242] The authentication request message includes GET_DIGESTS (for example, 4 bytes), GET_CERTIFICATE (for example, 8 bytes), and CHALLENGE (for example, 36 bytes).

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

[0244] An authentication message may also be called an authentication packet, authentication data, or authentication control information. Messages such as GET_DIGEST and DIGESTS may also be called GET_DIGEST packets and DIGEST packets.

[0245] The procedure by which the wireless power receiving device authenticates the wireless power transmitting device based on such an authentication message will be described below.

[0246] (1) Authentication of a wireless power transmitter by a wireless power receiver (PTx by PRx)

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

[0248] [Table 6]

[0249] Table 6 shows an example of the required time for each authentication message when the power contract is based on the result of GET_DIGESTS during the negotiation phase. If the wireless power receiving device already knows the DIGEST for the wireless power transmitting device, the GET_CERTIFICATE and CERTIFICATE transmission / reception steps can be omitted. Also, the power contract can be updated in the renegotiation phase depending on the authentication result.

[0250] [Table 7]

[0251] Table 7 shows another example of the required time for each authentication message when the power contract is based on the result of GET_DIGESTS during the negotiation phase. If the wireless power receiving device already knows the DIGEST for the wireless power transmitting device, the GET_CERTIFICATE and CERTIFICATE transmission / reception steps can be omitted. Also, the power contract can be updated in the renegotiation phase depending on the authentication result. The following describes an authentication procedure for satisfying the required time.

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

[0253] As shown in FIG. 18, the wireless power receiving device transmits GET_DIGESTS to the wireless power transmitting device to acquire or retrieve the certificate chain DIGESTS of the wireless power transmitting device (S1800). Here, REQUEST=PTx's DIGEST is set. The pre-determined operation for step S1800 may include an operation in which the wireless power receiving device confirms support for the authentication function in the capability packet received from the wireless power transmitting device. The wireless power receiving device may transmit GET_DIGESTS to the wireless power transmitting device using a general request packet during the negotiation phase or renegotiation phase. That is, GET_DIGESTS may be transmitted carried in the general request packet.

[0254] 19 is an example of a 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 may indicate, for example, a header of DIGEST of the wireless power transmitting device.

[0255] 20 is another example of the message structure of GET_DIGESTS. As shown in FIG. 20, GET_DIGESTS is, for example, one byte and includes reserved 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.

[0256] 18, the wireless power transmitting device sends DIGESTS to the wireless power receiving device as a response to GET_DIGESTS (S1805). DIGESTS is used by the authentication responder to send a report on certificate chain digests and which slots contain valid certificate chain digests. The parameter of DIGESTS may be 32 bytes of the hash value of the certificate chain.

[0257] FIG. 21 shows the physical packet structure for transmitting DIGESTS and a method for transmitting the packet. As shown in FIG. 21, a DIGESTS packet includes a 32-byte DIGESTS payload, a 1-byte header indicating that the packet is related to DIGESTS, and a 2-byte header indicating the length of the packet. Meanwhile, the wireless power transmission apparatus divides such a DIGESTS 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 the resulting sequence of 4-byte DIGESTS small packets. The size of the last small packet in such a sequence may be smaller than 4 bytes. The small packets may also be called segments. In the example shown in FIG. 21, the size of the transmission packet of the wireless power transmission apparatus is limited so that one authentication response consists of a maximum of 4 bytes. Dividing one response message into a series of small packets in this manner allows the wireless power receiving device to periodically (approximately 250 ms) transmit (extended) control error packets (CEPs) and (extended) received power packets (RPPs) to the transmitting device, thereby allowing the operating point for power transmission and foreign object detection of the wireless power transmitting device to be efficiently managed.

[0258] 18, if the wireless power transmitting device acknowledges that it has already been authenticated previously, authentication is successful. If the wireless power receiving device does not acknowledge DIGESTS, the wireless power receiving device continues authentication during the power transmission phase. Steps S1800 and S1805 can be performed during the negotiation or renegotiation phase. Alternatively, steps S1800 and S1805 can be performed during the power transmission phase.

[0259] Next, the wireless power receiving device transmits GET_CERTIFICATE to the wireless power transmitting device to obtain a certificate chain of the wireless power transmitting device (S1810). Here, GET_CERTIFICATE is set by an offset and a length. GET_CERTIFICATE is used to read a segment of the target certificate chain.

[0260] FIG. 22 shows an example of the message structure of GET_CERTIFICATE. As shown in FIG. 22, GET_CERTIFICATE can be, for example, two bytes and can include an offset and a length field. 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 of the read request in bytes. For example, to read 4 bytes from the start of the certificate chain, the offset [11...0] of GET_CERTIFICATE can have a value of 00b and the length = 11b.

[0261] 18, the wireless power transmitting device transmits at least a part of the certificate chain to the wireless power receiving device in response to the GET_CERTIFICATE (S1815). At this time, the part of the certificate chain may start after the start point of the certificate chain by the offset in bytes.

[0262] Fig. 23 shows an example of a physical packet structure for transmitting a certificate and a method for transmitting the same. As shown in Fig. 23, when transmitting a 1536-byte certificate packet, the wireless power transmitting apparatus extracts a 4-byte 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, thereby generating and transmitting a certificate segment with a total length of 6 bytes.

[0263] FIG. 24 illustrates an example of a physical packet structure for transmitting an authentication response message from a wireless power transmission device and a method for transmitting the same. As shown in FIG. 24, a certificate packet (e.g., 1543 bytes) can include a certificate chain (e.g., 1540 bytes), a header (e.g., 1 byte) indicating that the certificate is a certificate, and a header (e.g., 2 bytes) indicating the length of the certificate packet. Meanwhile, the wireless power transmission device divides the certificate 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 the resulting small packets as a sequence of 4-byte certificate small packets. In this case, a total of 515 data chunks are transmitted. The size of the last small packet in the sequence may be smaller than 4 bytes. The small packets may also be called segments. In the example of FIG. 24, the size of the transmission packet from the wireless power transmission device is limited so that one authentication response consists of a maximum of 4 bytes. Dividing one response message into a series of small packets in this manner allows the wireless power receiving device to periodically (approximately 250 ms) transmit (extended) control error packets (CEPs) and (extended) received power packets (RPPs) to the transmitting device, thereby allowing the operating point for power transmission and foreign object detection of the wireless power transmitting device to be efficiently managed.

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

[0265] Thereafter, the wireless power receiving device can repeat steps S1810 to S1820 until all certificate chains are read.

[0266] The wireless power receiving device transmits a challenge to the wireless power transmitting device (S1825). The challenge is used to initiate authentication of the product.

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

[0268] 18 again, the wireless power receiving apparatus transmits GET_CHALLENGE_AUTH to the wireless power transmitting apparatus to obtain CHALLENGE_AUTH (S1830), where GET_CHALLENGE_AUTH can be set by an offset and a length.

[0269] The wireless power transmitting apparatus transmits a part of CHALLENGE_AUTH to the wireless power receiving apparatus as a response to GET_CHALLENGE_AUTH (S1835). At this time, the part of CHALLENGE_AUTH may start after the start of the part of CHALLENGE_AUTH by the offset in bytes.

[0270] 26 shows an example of a physical packet structure for transmitting a CHALLENGE_AUTH packet and a method for transmitting the packet. As shown in FIG. 26, a CHALLENGE_AUTH packet (e.g., 1600 bytes) may 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, based on the offset and length specified by GET_CHALLENGE_AUTH, the wireless power transmitting apparatus extracts only a specific length (e.g., 4 bytes) of the CHALLENGE_AUTH packet from the offset, adds a header indicating that it is a CHALLENGE_AUTH packet 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.

[0271] Referring again to FIG. 18, if necessary, the wireless power receiving apparatus may transmit a control error (CE) packet and / or a received power packet (RPP) to the wireless power transmitting apparatus (S1840).

[0272] Thereafter, the wireless power receiving device can repeat steps S1830 to S1840 until all certificate chains are read.

[0273] Next, a procedure for the wireless power transmitting apparatus to authenticate the wireless power receiving apparatus based on the authentication message will be described.

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

[0276] [Table 8]

[0277] Table 8 shows an example of the required time for each authentication message when the power contract is based on the result of GET_DIGESTS during the negotiation phase. If the wireless power transmitting device already knows the DIGEST for the wireless power receiving device, the GET_CERTIFICATE and CERTIFICATE transmission / reception steps can be omitted. Also, the power contract can be updated 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 result of GET_DIGESTS during the negotiation phase. If the wireless power transmitting device already knows the DIGEST for the wireless power receiving device, the control error packet transmission step, communication request step, and GET_CERTIFICATE and CERTIFICATE transmission / reception step can be omitted. Also, the power contract can be updated in the renegotiation phase depending on the authentication result. The following describes an authentication procedure for satisfying the required time.

[0280] FIG. 27 is a flowchart showing a sequence of packets transmitted and received when a wireless power transmitting apparatus performs authentication of a wireless power receiving apparatus (authentication of PRx by PTx) according to an embodiment.

[0281] As shown in FIG. 27, the wireless power transmitting device receives DIGESTS transmitted from the line power receiving device (S2700). DIGESTS is used by the authentication responder to transmit certificate chain digests and a report regarding which slots contain valid certificate chain digests. The parameter of DIGESTS may be a 32-byte hash value of the certificate chain. Predetermined operations for step S2700 may include an operation in which the wireless power receiving device confirms support for the authentication function in a capability packet received from the wireless power transmitting device, and an operation in which the wireless power transmitting device transmits GET_DIGESTS to the wireless power receiving device. Step S2700 may be performed during the negotiation or renegotiation phase or the power transmission phase.

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

[0283] Referring back to FIG. 27, during the power transmission phase, the wireless power receiving apparatus transmits a control error packet or a received power packet to the wireless power transmitting apparatus (S2705).

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

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

[0286] 29 shows an example of the structure of a GET_CERTIFICATE message transmitted by a wireless power transmitting apparatus. As shown in FIG. 29, GET_CERTIFICATE may be, for example, two bytes long and may include an offset and a length field. Here, the offset is an offset in bytes from the start of the certificate chain to where the read request begins. The length is the length of the read request in bytes. For example, to read 40 bytes from the start of the certificate chain, the offset [7...0] of GET_CERTIFICATE may be 00b and the length may be 110000b.

[0287] 27 again, the wireless power receiving apparatus transmits at least a part of the certificate chain to the wireless power transmitting apparatus in response to the GET_CERTIFICATE (S2725). At this time, the part of the certificate chain may start after the start point of the certificate chain by the offset in bytes.

[0288] 30 shows an example of a physical packet structure for transmitting a certificate of a wireless power receiving device and a method for transmitting the same. As shown in FIG. 30, when transmitting a 1536-byte certificate packet, the wireless power receiving device extracts a 40-byte 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, thereby generating and transmitting a certificate segment with a total length of 42 bytes.

[0289] Referring again to FIG. 27, the wireless power transmission device can repeat steps S2710 to S2725 until all certificate chains have been read.

[0290] If necessary, the wireless power receiving device may transmit a control error (CE) packet and / or a received power packet (RPP) to the wireless power transmitting device (S2730).

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

[0292] When the wireless power receiving device responds with an ACK to the request for communication (S2740), the wireless power transmitting device transmits a CHALLENGE[n] to the wireless power receiving device (S2745). The CHALLENGE is used to initiate product authentication.

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

[0294] Referring again to FIG. 27, after receiving an ACK from the wireless power receiving device, the wireless power transmitting device can repeat steps S2735 to S2750 until all CHALLENGES are transmitted.

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

[0296] When the wireless power receiving apparatus responds with ACK to the request for communication (S2765), the wireless power transmitting apparatus transmits GET_CHALLENGE_AUTH to the wireless power receiving apparatus to obtain CHALLENGE_AUTH (S2770), where GET_CHALLENGE_AUTH can be set by an offset and a length.

[0297] The wireless power receiving apparatus transmits at least a portion of the CHALLENGE_AUTH to the wireless power transmitting apparatus in response to the GET_CHALLENGE_AUTH (S2775). At this time, the at least a portion of the CHALLENGE_AUTH may start after the offset from the start of the length in bytes.

[0298] 32 shows an example of a physical packet structure for transmitting a CHALLENGE_AUTH packet from a wireless power receiving device and a method for transmitting the packet. As shown in FIG. 32, a CHALLENGE_AUTH packet (e.g., 160 bytes) may 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 wireless power transmitting device extracts a specific length (e.g., 40 bytes) of the CHALLENGE_AUTH packet from the offset based on the offset and length specified in GET_CHALLENGE_AUTH, adds a header (e.g., 1 byte) indicating that the CHALLENGE_AUTH packet is a CHALLENGE_AUTH packet to the front end, and adds a checksum (e.g., 1 byte) to the rear end, thereby generating and transmitting a certificate segment with a total length of 42 bytes.

[0299] Thereafter, the wireless power transmitting apparatus can repeat steps S2760 to S2775 until all CHALLENGE_AUTHs have been read.

[0300] FIG. 33 illustrates an example of a physical packet structure for transmitting an authentication response message of a wireless power receiving device and a method for transmitting the same. As illustrated in FIG. 33, for example, a certificate packet (e.g., N bytes) may include a certificate chain, a header (e.g., 1 byte) indicating that the certificate is a certificate, and a header (e.g., 2 bytes) indicating the length of the certificate packet. Meanwhile, the wireless power receiving device divides such a certificate 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 the resulting small certificate packet as a sequence of M bytes. The size of the last small packet in the sequence may be smaller than M bytes. The small packets may also be called segments. In the example of FIG. 33, the size of the transmission packet of the wireless power receiving device is limited so that one authentication response consists of M bytes. In this way, dividing one response message into a series of small packets allows the wireless power receiving device to periodically (approximately 250 ms) transmit (extended) control error packets (CEPs) and (extended) received power packets (RPPs) to the transmitting device, thereby allowing the operating point for power transmission and foreign object detection of the wireless power transmitting device to be efficiently managed.

[0301] FIG. 34 illustrates another example of a physical packet structure for transmitting an authentication response message of a wireless power receiving device and a method for transmitting the same. As illustrated in FIG. 34, for example, a certificate packet (e.g., 1543 bytes) may include a certificate chain (e.g., 1540 bytes), a header (e.g., 1 byte) indicating that the certificate is a certificate, and a header (e.g., 2 bytes) indicating the length of the certificate packet. Meanwhile, the wireless power receiving device divides the certificate 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 the small packets, and adds a checksum (e.g., 1 byte) to the rear end of the small packets, thereby transmitting a sequence of 40-byte certificate 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 smaller than 40 bytes. The small packets may also be called segments. In the example of FIG. 34, the size of the transmission packets of the wireless power receiving device is limited so that one authentication response consists of 40 bytes. In this way, dividing one response message into a series of small packets allows the wireless power receiving device to periodically (approximately 250 ms) transmit (extended) control error packets (CEPs) and (extended) received power packets (RPPs) to the transmitting device, thereby allowing the operating point for power transmission and foreign object detection of the wireless power transmitting device to be efficiently managed.

[0302] FIG. 35 is a flowchart showing a sequence of packets transmitted and received when a wireless power transmitting apparatus according to another embodiment performs authentication of a wireless power receiving apparatus (authentication of PRx by PTx).

[0303] 35, the wireless power transmitting apparatus receives DIGESTS transmitted from the wireless power receiving apparatus (S3500). Predetermined operations for step S3500 may include an operation in which the wireless power receiving apparatus confirms support for the authentication function from a capability packet received from the wireless power transmitting apparatus, and an operation in which the wireless power transmitting apparatus transmits GET_DIGESTS to the wireless power receiving apparatus. Step S3500 may be performed in the negotiation phase or the power transmission phase.

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

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

[0306] When the wireless power receiving device responds to the request for multiple communication with an ACK (S3515), the wireless power transmitting device sends a GET_CERTIFICATE to the wireless power receiving device to obtain the certificate chain of the wireless power receiving device or a CHALLENGE_AUTH response (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 receiving apparatus transmits at least a portion of the certificate chain to the wireless power transmitting apparatus in response to the GET_CERTIFICATE (S3525). At this time, the portion of the certificate chain may start after the offset from the start of the certificate chain in bytes.

[0308] The wireless power transmitting device can repeat steps S3520 to S3525 until all certificate chains are read.

[0309] If necessary, the wireless power receiving device may transmit a control error (CE) packet and / or a received power (RPP) packet to the wireless power transmitting device (S3530).

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

[0311] When the wireless power receiving device responds with an ACK to the request for multiple communication (S3540), the wireless power transmitting device transmits a CHALLENGE[n] to the wireless power receiving device (S3545). The CHALLENGE is used to initiate product authentication.

[0312] After receiving an ACK from the wireless power receiving device (S3550), the wireless power transmitting device may repeat steps S3545 to S3550 until all CHALLENGES are transmitted.

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

[0314] When the wireless power receiving apparatus responds to the request for multiple communication with an ACK (S3565), the wireless power transmitting apparatus transmits a GET_CHALLENGE_AUTH to the wireless power receiving apparatus to obtain a CHALLENGE_AUTH (S3570), where the GET_CHALLENGE_AUTH can be set by an offset and a length.

[0315] The wireless power receiving apparatus transmits at least a portion of the CHALLENGE_AUTH to the wireless power transmitting apparatus in response to the GET_CHALLENGE_AUTH (S3575). At this time, the at least a portion of the CHALLENGE_AUTH may start after the offset from the start of the length in bytes.

[0316] Thereafter, the wireless power transmitting apparatus can repeat steps S3570 to S3575 until all CHALLENGE_AUTHs have been read.

[0317] 5. Lower-level protocols supporting the authentication procedure

[0318] Low level packet transmission protocols that support authentication procedures may be based on in-band communication, so the packet structure used in the in-band communication must be adapted to the authentication procedures and authentication messages.

[0319] 36 is a diagram illustrating a structure of a packet transmitted from a wireless power receiving apparatus to a wireless power transmitting apparatus in in-band communication. The packet shown in FIG. 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, a header, a message, and a checksum. For example, the preamble is set to 11 bits, the header to 1 B, and the checksum to 1 B (1 B → 11 bits).

[0321] 37 is a diagram illustrating a structure of a packet transmitted from a wireless power transmitting apparatus to a wireless power receiving apparatus in in-band communication. The packet shown in FIG. 37 can be modulated by FSK modulation.

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

[0323] (1) Lower-level authentication sequence

[0324] 1) Authentication of a wireless power transmitter by a wireless power receiver (Authentication of PTx by PRx)

[0325] When the wireless power receiving apparatus is an authentication initiator, the wireless power transmitting apparatus becomes an authentication responder. Alternatively, the wireless power transmitting apparatus can be expressed as an (authentication) target apparatus. As an authentication initiator, the wireless power receiving apparatus transmits a message (or packet) to the wireless power transmitting apparatus requesting a message (or packet) required for authenticating the wireless power transmitting apparatus. As an authentication responder, the wireless power transmitting apparatus transmits an authentication response message consisting of a sequence of various packets to the wireless power receiving apparatus. The process of transmitting and receiving such a series of messages can be defined by a lower-level packet transmission protocol.

[0326] 38 is a diagram illustrating a packet transmission / reception sequence between a wireless power receiving apparatus and a transmitting apparatus from a lower level perspective according to an embodiment. Fig. 38 illustrates a process in which the wireless power transmitting apparatus transmits an authentication response packet (DIGESTS) to the wireless power receiving apparatus in response to the wireless power receiving apparatus transmitting a GET_DIGESTS to the wireless power transmitting apparatus.

[0327] As shown in Fig. 38, the wireless power transmitting apparatus waits for an ACK / NACK or continue / stop to be transmitted from the wireless power receiving apparatus after transmitting each packet of the sequence. The ACK / NACK or continue / stop is transmitted in an extended control error packet (CEP) as shown in Fig. 39. The wireless power transmitting apparatus and / or receiving apparatus repeat the following procedure until all packets of the sequence are transmitted.

[0328] If the wireless power transmitter receives "ACK and Continue", the wireless power transmitter transmits the next packet.

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

[0330] If the wireless power transmitter receives "NACK and Continue", the wireless power transmitter retransmits the previous packet.

[0331] If the wireless power transmitter receives a "NACK and Abort", it waits until it receives the next extended CEP containing an "ACK and Continue".

[0332] 39 is a diagram illustrating a packet transmission / reception sequence between a wireless power receiving apparatus and a transmitting apparatus from a lower level perspective according to another embodiment. Fig. 39 illustrates a process in which the wireless power transmitting apparatus transmits an authentication response packet (CERTIFICATE) to the wireless power receiving apparatus in response to the wireless power receiving apparatus transmitting a GET_CERTIFICATE to the wireless power transmitting apparatus.

[0333] As shown in Fig. 39, the wireless power transmitting apparatus waits for an ACK / NACK or continue / stop to be transmitted from the wireless power receiving apparatus after transmitting each packet of the sequence. The ACK / NACK or continue / stop is transmitted in an extended control error packet (CEP) as shown in Fig. 39. The wireless power transmitting apparatus and / or receiving apparatus repeat the following procedure until all packets of the sequence are transmitted.

[0334] If the wireless power transmitter receives "ACK and Continue," it transmits the next packet. For example, for packet (1), it can receive "ACK and Continue" by an extended control error packet (CEP), and for packet (m), it can receive "ACK and Continue" by an extended received power packet (Extended RPP) as shown in Figure 42.

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

[0336] If the wireless power transmitter receives "NACK and Continue", the wireless power transmitter retransmits the previous packet.

[0337] If the wireless power transmitter receives a "NACK and Abort", the wireless power transmitter waits until it receives the next extended CEP containing an "ACK and Continue".

[0338] FIG. 40 is an extended control error packet structure according to one embodiment.

[0339] 40, the wireless power receiving device transmits an extended control / error packet in response to the packet from the wireless power transmitting device, where the extended control / error packet includes not only a control error value for adjusting the operating point of the wireless power transmitting device but also at least one of ACK / NACK or continue / stop.

[0340] For example, suspend is 1 bit, and when its value is '1'b, it indicates that the wireless power transmitting apparatus suspends packet transmission, and when its value is '0'b, it indicates that the wireless power transmitting apparatus transmits the next packet in the sequence (i.e., continues transmission). Here, when the wireless power receiving apparatus needs to transmit CEPs in a short period to quickly adjust the operating point of the wireless power transmitting apparatus, or when all response packets have been received, the wireless power receiving apparatus can enforce the wireless power transmitting apparatus to suspend transmitting packets in the next sequence by setting suspend to '1'.

[0341] The ACK / NACK is, for example, 4 bits, and a value of '0000'b indicates ACK, and a value of '1111'b indicates NACK. ACK indicates that the wireless power receiving device successfully receives a packet without an error condition, and NACK indicates that the wireless power receiving device requests the wireless power transmitting device to retransmit the packet due to the occurrence of a packet reception error.

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

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

[0344] FIG. 42 is an extended received power packet structure according to one embodiment.

[0345] 42, the extended received power packet is 24 bits and can include a first reserved bit, a mode, a received power value, a second reserved bit, stop, and ACK / NACK. That is, the extended received power packet not only includes the received power value related to the FOD of the wireless power transmitting device, but also includes at least one of ACK / NACK or continue / stop.

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

[0347] The ACK / NACK is, for example, 4 bits, and a value of '0000'b indicates ACK, and a value of '1111'b indicates NACK. ACK indicates that the wireless power receiving device successfully receives a packet without an error condition, and NACK indicates that the wireless power receiving device requests the wireless power transmitting device to retransmit the packet due to the occurrence of a packet reception error.

[0348] 2) Authentication of a wireless power receiving device by a wireless power transmitting device (Authentication of PRx by PTx)

[0349] When the wireless power transmitting apparatus is an authentication initiator, the wireless power receiving apparatus becomes an authentication responder. Alternatively, the wireless power receiving apparatus can be expressed as an (authentication) target apparatus. As an authentication initiator, the wireless power transmitting apparatus transmits a message (or packet) to the wireless power receiving apparatus requesting a message (or packet) required for authenticating the wireless power receiving apparatus. As an authentication responder, the wireless power receiving apparatus transmits an authentication response message consisting of a sequence of various packets to the wireless power transmitting apparatus. The process of transmitting and receiving such a series of messages can be defined by a lower-level packet transmission protocol.

[0350] 43 is a diagram illustrating a packet transmission / reception sequence between a wireless power receiving apparatus and a transmitting apparatus from a lower level perspective according to an embodiment. Fig. 43 illustrates a process in which the wireless power receiving apparatus receives an authentication response packet (CERTIFICATE) from the wireless power transmitting apparatus in response to the wireless power transmitting apparatus sending GET_CERTIFICATE to the wireless power transmitting apparatus.

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

[0352] If the wireless power receiving device receives "ACK," it transmits the next packet. For example, if it receives ACK for packet (1), it transmits packet (2) at the next transmission timing.

[0353] If the wireless power receiving device receives a "NACK", the wireless power receiving device retransmits the previous packet.

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

[0355] In the following, a data transaction protocol is disclosed. For low-level data exchange, the present embodiment considers four rules:

[0356] Rule 1 is that the wireless power receiving device operates as a master. When the wireless power receiving device operates as a master and the wireless power transmitting device operates as a slave, the wireless power receiving device determines when communication with the wireless power transmitting device is permitted.

[0357] The wireless power receiving apparatus can transmit a start of data stream (SOD) ADT_CTRL packet to inquire whether the wireless power transmitting apparatus has a data stream to transmit, or can transmit a general request packet (GRP) with request set to '0xFF' to poll the wireless power transmitting apparatus to see whether the wireless power transmitting apparatus has a packet to send.

[0358] Rule 2 is communication error control. The wireless power receiving device or transmitting device can rewrite the ADT packet until it receives an ACK. When no communication error occurs, an "ACK" ADT_CTRL packet is sent, and when a communication error is detected, a "NACK" ADT_CTRL packet is sent.

[0359] Rule 3 is data stream synchronization: for synchronization purposes, the header of the ADT data packet can be toggled every time a new ADT data packet is sent.

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

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

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

[0363] The following describes in detail the lower-level data transport and packet structure for authentication. The design methods for lower-level data transport are roughly divided into two methods: a dedicated mapping method and a generic bit pipe method. The generic bit pipe method provides application-agnostic data transmission and has the advantage that it can be used for other applications in addition to authentication.

[0364] The design requirements for lower-level data transport based on a general bit pipe are i) to minimize interaction between the upper level and the lower level, and ii) to ensure error recovery and synchronized lower-level data transport. Regarding i), the upper level encodes and pushes (writes) a data stream to the lower level and decodes (reads) the data stream provided from the lower level. In addition, the lower level writes or reads (writes / reads) the data stream using multiple auxiliary data transport (ADT) data packets. Regarding ii), a simple and robust communication error-recovery mechanism includes an operation of rewriting ADT packets until the wireless power transmitting device or receiving device receives an ACK, and an operation of rereading ADT packets until there is no communication error. Also, simple synchronization of the data stream between the wireless power transmitter and receiver involves toggling the header of the data packet when transporting a new ADT data packet.

[0365] Figure 44 is a diagram illustrating 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) that optionally includes an ACK or NACK, an auxiliary data transport (ADT), a charge status packet (CSP), a proprietary packet, a renegotiation (RNG) packet that optionally includes an ACK or NACK, and a spare packet (the wireless power transmitter must be resilient to the spare bit).

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

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

[0369] As shown in FIG. 45, the ADT includes an ADT (ADT_PRx) related to the wireless power receiving device and an ADT (ADT_PTx) related to the wireless power transmitting device.

[0370] The ADT for the wireless power receiving device carries data or response (eg, ACK, NACK, RFA) packets or control packets from the wireless power receiving device.

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

[0372] As an example, the header of the ADT packet may indicate a lower-level data packet for a higher-level application (e.g., a lower-level data packet of a wireless power receiving device or a lower-level data packet of a wireless power transmitting device). The higher-level application may include, for example, an authentication procedure, a proprietary information exchange, a firmware update, or a power capabilities control of a wireless power transmitting device.

[0373] As another example, the header of the ADT packet may indicate a logical layer data packet (e.g., a wireless power receiving device packet or a wireless power transmitting device packet). As yet another example, the header of the ADT packet may include a control packet.

[0374] As another example, the header of an ADT packet may indicate an ADT data packet, but in this case, the header of the ADT data packet may include 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 transmitted.

[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 include a single type of header.

[0376] The following describes the ADT packet structure as a lower-level data transport. As described above, the ADT consists of a pair of an ADT (ADT_PRx) related to a wireless power receiving device and an ADT (ADT_PTx) related to a wireless power transmitting device, and the ADT (ADT_PRx) related to the wireless power receiving device is started first.

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

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

[0379] [Table 10]

[0380] Referring to Table 10, when a specific byte of payload is transmitted in an ADT data packet, Header A or Header B can be used. The payload size can range from 1 byte to 16 bytes. The wireless power receiving apparatus and the wireless power transmitting apparatus 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, when the wireless power receiving apparatus transmits a 1-byte payload in an ADT data packet, the wireless power receiving apparatus 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 can maintain the previous header value when retransmitting the previous ADT data packet. The previous ADT data packet can be retransmitted when the wireless power receiving apparatus receives a NACK response from the wireless power transmitting apparatus or when the wireless power receiving apparatus detects a decoding error in the wireless power transmitting apparatus.

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

[0382] 47, the ADT response packet for the wireless power receiving device 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 instruction content.

[0383] [Table 11]

[0384] In Table 11, a payload value of '11111111'b indicates that the wireless power receiving apparatus successfully received and decoded the ADT data packet transmitted by the wireless power transmitting apparatus in the previous ADT (ACK). A payload value of '00000000'b indicates that the wireless power receiving apparatus did not successfully receive or decode the ADT data packet transmitted by the wireless power transmitting apparatus in the previous ADT (NACK). In this case, the wireless power transmitting apparatus 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 wireless power receiving apparatus has requested the wireless power transmitting apparatus to transmit response data (RFA). In Table 11, the payload values ​​and their instructions are merely examples, and any number of different payload values ​​corresponding to each instruction may be used, and these also fall within the technical scope of the present invention.

[0385] Meanwhile, the structure of the ADT control packet for the wireless power receiving device may be the same as the ADT packet structure shown in FIG.

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

[0387] 48, the ADT control packet for the wireless power receiving device is, for example, 1 byte, and its value can indicate ACK, NACK, SOD, or EOD. Table 12 shows the correspondence between the payload value of the ADT control packet and its instruction content.

[0388] [Table 12]

[0389] In Table 12, a payload value of '11111111'b indicates that the wireless power receiving device successfully received and decoded the ADT data packet transmitted by the wireless power transmitting device in the previous ADT (ACK). A payload value of '00000000'b indicates that the wireless power receiving device did not successfully receive or decode the ADT data packet transmitted by the wireless power transmitting device in the previous ADT (NACK). In this case, the wireless power transmitting device 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 a request for the start of an ADT data stream (SOD). A payload value of '11001100'b indicates the end of an ADT data stream (EOD).

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

[0391] In the following, ADT (ADT_PTx) for a wireless power transmission device is disclosed.

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

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

[0394] [Table 13]

[0395] Referring to Table 13, when a specific byte of payload is transmitted in an ADT data packet, Header A or Header B can be used. The size of the payload can be 1 byte to 4 bytes. The wireless power transmitting apparatus and the wireless power receiving apparatus 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, when the wireless power transmitting apparatus transmits a 1-byte payload in an ADT data packet, the wireless power transmitting apparatus 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 can maintain the previous header value when retransmitting the previous ADT data packet. The previous ADT data packet can be retransmitted when the wireless power transmitting apparatus receives a NACK response from the wireless power receiving apparatus or when the wireless power transmitting apparatus detects a decoding error in the wireless power receiving apparatus.

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

[0397] 50, the ADT response packet for a wireless power transmission device 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 content.

[0398] [Table 14]

[0399] In Table 14, a payload value of '11111111'b indicates that the wireless power transmitter successfully received and decoded the ADT data packet transmitted by the wireless power receiver in the previous ADT (ACK). A payload value of '00000000'b indicates that the wireless power transmitter did not successfully receive or decode the ADT data packet transmitted by the wireless power receiver in the previous ADT (NACK). In this case, the wireless 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 wireless power transmitter has requested the wireless power receiver to transmit response data (RFA). The payload values ​​and their instructions in Table 14 are merely examples, and any number of different payload values ​​corresponding to each instruction may be used, and these are also within the technical scope of the present invention.

[0400] FIG. 51 is a structure of an ADT response / control packet (ADT_PTx Response / Control Packet) for a wireless power transmitting device according to one embodiment.

[0401] 51, the ADT response packet for a wireless power transmission device 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 content.

[0402] [Table 15]

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

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

[0405] 52, the ADT control packet for a wireless power transmission device is, for example, 1 byte, and its value can indicate 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 wireless power transmitter successfully received and decoded the ADT data packet transmitted by the wireless power receiver in the previous ADT (ACK). A payload value of '00000000'b indicates that the wireless power transmitter did not successfully receive or decode the ADT data packet transmitted by the wireless power receiver in the previous ADT (NACK). In this case, the wireless 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 a request for the start of an ADT data stream (SOD). A payload value of '11001100'b indicates the end of an ADT data stream (EOD). The payload values ​​and their instructions in Table 16 are merely examples, and any number of different payload values ​​corresponding to each instruction can be used, and these also fall within the technical scope of the present invention.

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

[0409] 2) Low-level data exchange sequence for authentication (ADT basis)

[0410] FIG. 53 is a diagram illustrating a state machine for an ADT data packet write according to one embodiment.

[0411] As shown in FIG. 53, the transmitting side and / or receiving side synchronize the data stream according to Rule 3 as shown in FIG. 53. That is, for synchronization, the header of ADT data packet [n] may be toggled every time a new ADT data packet [n] is transmitted. The header of the ADT packet may indicate the ADT data packet. In this case, the header of the ADT data packet may include multiple types of headers (e.g., header A and header B, i.e., two types of headers). Data stream synchronization may be achieved by toggling the header of the ADT data packet from A to B or B to A every time a new ADT data packet is successfully transmitted (ACK). When the wireless power receiving device receives a NACK response from the wireless power transmitting device or when the wireless power receiving device detects a decoding error of the wireless power transmitting device, the previous ADT data packet is retransmitted, and in this case, the previous header value is maintained as is.

[0412] 2-1) Authentication of a wireless power transmitter by a wireless power receiver (Authentication of PTx by PRx)

[0413] As a lower level authentication sequence of the ADT platform, first, authentication of a wireless power transmitting device by a wireless power receiving device will be described (PRx=Initiator / PTx=Responder).

[0414] FIG. 54 is a diagram illustrating a transmission sequence at an upper level and a high level between a wireless power receiving device and a wireless power transmitting device when exchanging ADT data packets according to one embodiment.

[0415] As shown in FIG. 54, H_A indicates an A-type header, and H_b indicates a B-type header. When data #1 from an upper level in a wireless power receiving device (sender) is transferred to a lower level and transmitted to a wireless power transmitting device together with header A, the lower level of the wireless power transmitting device transfers data #1 to the upper level. If data #1 is successfully received, the wireless power transmitting device transmits an ACK for data #1 to the wireless power receiving device. The wireless power receiving device transmits new data #2 from the upper level to the lower level and then transmits it to the wireless power transmitting device together with header B. If the wireless power transmitting device fails to receive data #2, it transmits a NACK to the wireless power receiving device. Having received the NACK, the wireless power receiving device retransmits data #2 together with the immediately preceding header B. In this manner, the wireless power receiving device and the wireless power transmitting device can ensure synchronization and realize a simple and robust error recovery and synchronization mechanism.

[0416] 55 is a diagram illustrating an upper level and high level transmission sequence between a wireless power receiving device and a wireless power transmitting device when exchanging ADT data packets according to another embodiment. Here, the wireless power receiving device is the authentication initiator, and the wireless power transmitting device is the authentication responder. ADT data packet exchange between the wireless power receiving device and the transmitting device is performed according to the above-mentioned "(1) lower level authentication sequence" and "(2) lower level data exchange protocol."

[0417] As shown in FIG. 55, the wireless power receiving device generates an M-byte CHALLENGE message at an upper level and transmits it to a lower level, which then places it in an ADT data packet (or transport) and transmits it to the wireless power transmitting device.

[0418] According to the authentication sequence of the lower level, the ADT data packet for the CHALLENGE message can be transmitted several times, and while the ADT data packet is transmitted several times according to rule 2, the wireless power transmitting device transmits an ACK / NACK for each subsequent ADT data packet from the lower level to the wireless power receiving device and delivers the ADT data packet to the upper level. After this series of processes, when the transmission of the CHALLENGE message (from the perspective of the upper level) or the ADT data packet for the CHALLENGE message (from the perspective of the lower level) is completed, the wireless power receiving device adds EOD to the end of the ADT data packet for the CHALLENGE message according to rule 4 to indicate the completion of the transmission.

[0419] Meanwhile, the wireless power receiving apparatus inquires whether the slave wireless power transmitting apparatus has a data stream to transmit according to rule 1. For this purpose, the wireless power receiving apparatus can transmit an SOD. In this case, the wireless power receiving apparatus can repeatedly transmit an SOD until the wireless power transmitting apparatus responds with a data packet or until a timeout occurs. When the wireless power transmitting apparatus receives the SOD, the wireless power transmitting apparatus generates an N-byte CHALLENGE_AUTH_RESPONSE at the upper level and transmits it to the lower level, and the lower level loads it into an ADT data packet (or transport) and transmits it to the wireless power receiving apparatus.

[0420] According to the authentication sequence of the lower level, the ADT data packet for the CHALLENGE_AUTH_RESPONSE message can be transmitted several times, and while the ADT data packet is transmitted several times according to rule 2, the wireless power receiving device transmits an ACK / NACK for the next ADT data packet from the lower level to the wireless power transmitting device and delivers the ADT data packet to the upper level. After this series of processes, when the transmission of the CHALLENGE_AUTH_RESPONSE message (from the perspective of the higher level) or the ADT data packet for the CHALLENGE_AUTH_RESPONSE message (from the perspective of the lower level) is completed, the wireless power transmitting device adds EOD to the end of the ADT data packet for the CHALLENGE_AUTH_RESPONSE message to indicate the completion of the transmission according to rule 4.

[0421] FIG. 56 is a diagram illustrating a transmission sequence at an upper level and a high level between a wireless power receiving apparatus and a wireless power transmitting apparatus when exchanging ADT data packets according to still another embodiment.

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

[0423] FIG. 57 is a diagram illustrating an exchange sequence of ADT data packets for an authentication request message according to one embodiment.

[0424] 57, when a bitstream (e.g., 35 bytes) for an authentication message is prepared, the wireless power receiving apparatus transmits an ADT data packet consisting of a header (e.g., 1 byte) and a payload (e.g., 34 bytes) to a lower level. Here, the authentication message may be, for example, a CHALLENGE message transmitted from the wireless power receiving apparatus to the transmitting apparatus.

[0425] Since an ADT data packet can be transmitted up to 16 bytes, the 35-byte authentication message is divided 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 transmitted.

[0426] First, in the first line, the wireless power receiving apparatus successfully transmits the zeroth ADT data packet (ADT_PRx(0)) and receives an ACK, but fails to transmit the first ADT data packet (ADT_PRx(1)) and receives a NACK. Then, in the second line, the wireless power receiving apparatus retransmits the first ADT data packet (ADT_PRx(1)) but fails to receive a response (ACK or NACK) to the retransmission and sends a NACK. In response, when the wireless power transmitting apparatus responds with an ACK, it is confirmed that the retransmission of the first ADT data packet (ADT_PRx(1)) was successful, so the wireless power receiving apparatus successfully transmits the remaining three bytes of the second ADT data packet (ADT_PRx(2)) and receives an ACK. In response, the wireless power receiving apparatus successfully transmits an EOD and receives an ACK, thereby ending the transmission of the authentication message.

[0427] Fig. 58 is a diagram illustrating an exchange sequence of ADT data packets related to an authentication request message according to another embodiment. The embodiment of Fig. 58 differs from the embodiment of Fig. 57 in that the wireless power receiving apparatus divides a total of 35 bytes of authentication message into a 16-byte zeroth ADT data packet (ADT_PRx(0)), a 16-byte first ADT data packet (ADT_PRx(1)), and a 3-byte second ADT data packet (ADT_PRx(2)) and transmits them, toggling the header of each ADT data packet (Header A<->Header B) according to Rule 3, and when retransmitting an ADT data packet, using the same header used previously (Header B in Fig. 58) to perform simplified synchronization and instruct retransmission.

[0428] Fig. 59 is a diagram illustrating an exchange sequence of ADT data packets related to an authentication request message according to yet another embodiment. The embodiment of Fig. 59 is the same as the embodiment of Fig. 58 in that the wireless power receiving apparatus divides an authentication message of a total of 35 bytes into a 16-byte zeroth ADT data packet (ADT_PRx(0)), a 16-byte first ADT data packet (ADT_PRx(1)), and a 3-byte second ADT data packet (ADT_PRx(2)) and transmits the divided messages, and toggles the header of each ADT data packet (Header A<->Header B) according to Rule 3. However, it differs from the embodiment of Fig. 58 in that SOD is added at the start of transmission of the ADT data packet.

[0429] Figure 60 is a diagram illustrating an ADT data packet exchange sequence for an authentication request message according to yet another embodiment. The embodiment of Figure 60 differs from the embodiment of Figure 58 in that the wireless power receiving apparatus divides a total of 35 bytes of authentication message into a 16-byte zeroth ADT data packet (ADT_PRx(0)), a 16-byte first ADT data packet (ADT_PRx(1)), and a 3-byte second ADT data packet (ADT_PRx(2)) and transmits them. When transmission of the second ADT data packet (ADT_PRx(2)) fails, the second ADT data packet (ADT_PRx(2)) is retransmitted with its header toggled, even though its header should not be toggled. Here, a bit pattern response may be used instead of an ADT response packet of the wireless power transmitting apparatus, thereby reducing the ADT exchange time.

[0430] 61 is a diagram illustrating an exchange sequence of ADT data packets for an authentication request message according to yet another embodiment. The embodiment of Fig. 61 illustrates a scenario in which the wireless power receiving apparatus divides a total of 35 bytes of authentication message into a 16-byte zeroth ADT data packet (ADT_PRx(0)), a 16-byte first ADT data packet (ADT_PRx(1)), and a 3-byte second ADT data packet (ADT_PRx(2)) and transmits the divided messages. The scenario illustrates a scenario in which the transmission of the zeroth ADT data packet (ADT_PRx(0)) and the 16-byte first ADT data packet (ADT_PRx(1)) is successful, but the transmission of the second ADT data packet (ADT_PRx(2)) fails due to no response.

[0431] FIG. 62 is a diagram illustrating an exchange sequence of ADT data packets for an authentication response message according to one embodiment.

[0432] As shown in Fig. 62, a bit stream (for example, 99 bytes) for an authentication response message is prepared. The authentication response message may be, for example, a CHALLENGE_AUTH_RESPONSE message transmitted from the wireless power transmitting apparatus to the receiving apparatus.

[0433] When using a communication protocol in the PTx → PRx direction (e.g., FSK), ADT data packets can be transmitted up to 4 bytes in length, so the 99-byte authentication response message is divided 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 transmitted.

[0434] First, when the wireless power receiving apparatus transmits an SOD to the wireless power transmitting apparatus for polling, the wireless power transmitting apparatus successfully transmits the 0th ADT data packet (ADT_PTx(0)) and then receives an ACK. However, the wireless power transmitting apparatus fails to transmit the first ADT data packet (ADT_PTx(1)) and receives a NACK. Thereafter, the wireless power transmitting apparatus retransmits the first ADT data packet (ADT_PTx(1)), but fails to receive an ACK for the retransmission and then transmits a NACK. In response to this, when the wireless power receiving apparatus responds with an ACK, it is confirmed that the retransmission of the first ADT data packet (ADT_PTx(1)) was successful, and the wireless power transmitting apparatus transmits the second ADT data packet (ADT_PTx(2)). After repeating this ADT packet transmission sequence, the wireless power transmitting apparatus successfully transmits the last remaining 3-byte 24th ADT data packet (ADT_PTx(24)) and then receives an ACK. In response to this, the wireless power transmitting device successfully transmits the EOD and receives an ACK, thereby completing the transmission of the authentication response message.

[0435] Fig. 63 is a diagram illustrating an exchange sequence of ADT data packets for an authentication response message according to another embodiment. The embodiment of Fig. 63 differs from the embodiment of Fig. 62 in that the wireless power transmission apparatus divides the authentication response message of a total of 99 bytes 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 the divided messages. The header of each ADT data packet is toggled (Header A<->Header B) according to Rule 3, and when the first ADT data packet is retransmitted, the same header used previously (Header B in Fig. 62) is used to perform simplified synchronization and instruct retransmission.

[0436] Fig. 64 is a diagram illustrating an exchange sequence of ADT data packets related to an authentication response message according to yet another embodiment. The embodiment of Fig. 64 is the same as the embodiment of Fig. 63 in that the wireless power transmission apparatus divides the authentication response message of a total of 99 bytes 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 the divided messages, and toggles the header of each ADT data packet (Header A<->Header B) according to Rule 3. However, it differs from the embodiment of Fig. 63 in that the wireless power reception apparatus uses GRP to poll the wireless power transmission apparatus, and the wireless power transmission apparatus responds with SOD to start transmission of the ADT data packets.

[0437] Fig. 65 is a diagram illustrating an exchange sequence of ADT data packets related to an authentication response message according to yet another embodiment. The embodiment of Fig. 65 differs from the embodiment of Fig. 64 in that the wireless power transmission apparatus divides the authentication response message of a total of 99 bytes 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 the divided packets. When transmission of the first ADT data packet (ADT_PTx(1)) fails, the header of the first ADT data packet (ADT_PTx(1)) is retransmitted with its header toggled, even though the header should not be toggled.

[0438] Fig. 66 is a diagram illustrating an exchange sequence of ADT data packets for an authentication response message according to yet another embodiment. The embodiment of Fig. 66 illustrates a scenario in which a wireless power transmission apparatus divides an authentication response message of a total of 99 bytes 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)), in which the transmission of the 0th ADT data packet (ADT_PTx(0)) is successful but the transmission of the 1st ADT data packet (ADT_PTx(1)) fails due to no response.

[0439] 2-2) Authentication of a wireless power receiving device by a wireless power transmitting device (Authentication of PRx by PTx)

[0440] As a lower level authentication sequence based on the ADT, authentication of a wireless power receiving device by a wireless power transmitting device will be described (PTx=Initiator / PRx=Responder). According to Rule 1, since the wireless power transmitting device is a slave, the wireless power receiving device must provide ADT to the wireless power transmitting device when it is confirmed that the wireless power transmitting device operates as an authentication initiator based on the AI ​​bit in the performance packet of the wireless power transmitting device.

[0441] 67 is a diagram illustrating an upper level and high level transmission sequence between a wireless power transmitting device and a wireless power receiving device when exchanging ADT data packets according to one embodiment. Here, the wireless power transmitting device is the authentication initiator, and the wireless power receiving device is the authentication responder. ADT data packet exchange between the wireless power transmitting device and the receiving device is performed according to the above-mentioned "(1) lower level authentication sequence" and "(2) lower level data exchange protocol."

[0442] 67, the wireless power transmitting device pools the SOD provided by the wireless power receiving device, generates an M-byte CHALLENGE message at an upper level, and transmits it to a lower level, which then loads it into an ADT data packet (or transport) and transmits it to the wireless power receiving device. In this case, the wireless power receiving device can repeatedly transmit the SOD until the wireless power transmitting device responds with an ADT data packet or until a timeout occurs.

[0443] According to the authentication sequence of the lower level, the ADT data packet for the CHALLENGE message can be transmitted several times, and while the ADT data packet is transmitted several times according to rule 2, the wireless power receiving device transmits an ACK / NACK for the next ADT data packet from the lower level to the wireless power transmitting device and delivers the ADT data packet to the upper level. After this series of processes, when the transmission of the CHALLENGE message (from the perspective of the upper level) or the ADT data packet for the CHALLENGE message (from the perspective of the lower level) is completed, the wireless power transmitting device adds EOD to the end of the ADT data packet for the CHALLENGE message according to rule 4 to indicate the completion of the transmission.

[0444] Meanwhile, since the wireless power receiving device operates as a master according to rule 1, it generates an N-byte CHALLENGE message at the upper level without any additional pooling for the CHALLENGE_AUTH_RESPONSE message it sends 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 transmitting device.

[0445] According to the authentication sequence of the lower level, the ADT data packet for the CHALLENGE_AUTH_RESPONSE message can be transmitted several times, and while the ADT data packet is transmitted several times according to rule 2, the wireless power transmitting device transmits an ACK / NACK for the next ADT data packet from the lower level to the wireless power receiving device and delivers the ADT data packet to the upper level. After this series of processes, when the transmission of the CHALLENGE_AUTH_RESPONSE message (from the perspective of the higher level) or the ADT data packet for the CHALLENGE_AUTH_RESPONSE message (from the perspective of the lower level) is completed, the wireless power receiving device adds EOD to the end of the ADT data packet for the CHALLENGE_AUTH_RESPONSE message to indicate the completion of the transmission according to rule 4.

[0446] FIG. 68 is a diagram illustrating a transmission sequence at an upper level and a high level between a wireless power transmitting apparatus and a wireless power receiving apparatus when exchanging ADT data packets according to another embodiment.

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

[0448] FIG. 69 is a diagram illustrating an exchange sequence of ADT data packets for an authentication request message according to one embodiment.

[0449] 69, when a bitstream (e.g., 35 bytes) for an authentication request message is prepared, the wireless power transmitting apparatus waits to transmit an ADT data packet consisting of a header (e.g., 1 byte) and a payload (e.g., 34 bytes) from a lower level. Here, the authentication request message may be, for example, a CHALLENGE message.

[0450] At this time, the wireless power receiving device performs a pooling operation to check whether there is data to be transmitted from the wireless power transmitting device, and as part of this, the wireless power receiving device repeatedly transmits SOD until the wireless power transmitting device responds or until a timeout occurs.

[0451] When the SOD gives the wireless power transmitter an opportunity to transmit an authentication request message, the wireless power transmitter starts transmitting an ADT data packet. When using the PTx → PRx communication protocol (FSK), an ADT data packet can be transmitted up to 4 bytes, so the 35-byte authentication message is divided into 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 data packet (ADT_PTx(8)) and transmitted.

[0452] First, the wireless power transmitting apparatus successfully transmits the zeroth ADT data packet (ADT_PTx(0)) and receives an ACK, but fails to transmit the first ADT data packet (ADT_PTx(1)) and receives a NACK. Thereafter, the wireless power transmitting apparatus retransmits the first ADT data packet (ADT_PTx(1)), but fails to receive an ACK response and transmits a NACK. In response to this, when the wireless power receiving apparatus responds with an ACK, it is confirmed that the retransmission of the first ADT data packet (ADT_PTx(1)) was successful, and the wireless power transmitting apparatus transmits the next, second ADT data packet (ADT_PTx(2)). When transmission of all ADT data packets up to the last one is completed, the wireless power transmitting apparatus successfully transmits an EOD and receives an ACK, thereby ending transmission of the authentication request message.

[0453] Fig. 70 is a diagram illustrating an exchange sequence of ADT data packets related to an authentication request message according to another embodiment. The embodiment of Fig. 70 differs from the embodiment of Fig. 70 in that the wireless power transmission apparatus divides a total of 35 bytes of the authentication request message into a 4-byte zeroth ADT data packet (ADT_PTx(0)), a 4-byte first ADT data packet (ADT_PTx(1)), ..., a 4-byte seventh ADT data packet (ADT_PTx(7)), and a 3-byte eighth ADT data packet (ADT_PTx(8)) and transmits the divided messages. The header of each ADT data packet is toggled (Header A<->Header B) according to Rule 3, and when an ADT data packet is retransmitted, the same header used previously (Header B in Fig. 58) is used to perform simplified synchronization and instruct the retransmission.

[0454] Fig. 71 is a diagram illustrating an exchange sequence of ADT data packets related to an authentication request message according to yet another embodiment. The embodiment of Fig. 71 is the same as the embodiment of Fig. 70 in that the wireless power transmission apparatus divides a total of 35 bytes of authentication request message into a 4-byte zeroth ADT data packet (ADT_PTx(0)), a 4-byte first ADT data packet (ADT_PTx(1)), ..., a 4-byte seventh ADT data packet (ADT_PTx(7)), and a 3-byte eighth ADT data packet (ADT_PTx(8)) and transmits the divided message, and toggles the header of each ADT data packet (Header A<->Header B) according to Rule 3. However, it differs from the embodiment of Fig. 70 in that the wireless power reception apparatus uses GRP to poll the wireless power transmission apparatus, and the wireless power transmission apparatus responds with SOD to start transmission of the ADT data packets.

[0455] Fig. 72 is a diagram illustrating an exchange sequence of ADT data packets related to an authentication request message according to yet another embodiment. The embodiment of Fig. 72 differs from the embodiment of Fig. 71 in that the wireless power transmission apparatus divides a total of 35 bytes of the authentication request message into a 4-byte zeroth ADT data packet (ADT_PTx(0)), a 4-byte first ADT data packet (ADT_PTx(1)), ..., a 4-byte seventh ADT data packet (ADT_PTx(7)), and a 3-byte eighth ADT data packet (ADT_PTx(8)) and transmits the divided messages. The embodiment of Fig. 72 differs from the embodiment of Fig. 71 in that the wireless power transmission apparatus obtains an opportunity to transmit the ADT data packets by transmitting an RPP in Mode 0 and an RFA bit pattern. Furthermore, the embodiment of Fig. 72 differs from the embodiment of Fig. 71 in that, when transmission of the first ADT data packet (ADT_PTx(1)) fails, the first ADT data packet (ADT_PTx(1)) is retransmitted with its header toggled, even though the header should not be toggled.

[0456] Fig. 73 is a diagram illustrating an exchange sequence of ADT data packets for an authentication request message according to yet another embodiment. The embodiment of Fig. 73 illustrates a scenario in which a wireless power transmission apparatus divides a total of 35 bytes of an authentication request message into a 4-byte zeroth ADT data packet (ADT_PTx(0)), a 4-byte first ADT data packet (ADT_PTx(1)), ..., a 4-byte seventh ADT data packet (ADT_PTx(7)), and a 3-byte eighth ADT data packet (ADT_PTx(8)), in which the transmission of the zeroth ADT data packet (ADT_PTx(0)) is successful, but there is no response to the first ADT data packet (ADT_PTx(1)), resulting in a transmission failure.

[0457] FIG. 74 is a diagram illustrating an exchange sequence of ADT data packets for an authentication response message according to one embodiment.

[0458] 74, when a bitstream (e.g., 99 bytes) for an authentication response message is prepared, the wireless power receiving apparatus transmits an ADT data packet consisting of a header (e.g., 1 byte) and a payload (e.g., 34 bytes) from a lower level. Here, the authentication response message may be, for example, a CHALLENGE_AUTH_RESPONSE message.

[0459] The wireless power receiving apparatus successfully transmits the zeroth ADT data packet (ADT_PRx(0)) and then receives an ACK. However, the wireless power receiving apparatus fails to transmit the first ADT data packet (ADT_PRx(1)) and receives a NACK. Thereafter, the wireless power receiving apparatus retransmits the first ADT data packet (ADT_PRx(1)), but fails to receive an ACK for the retransmission and transmits a NACK. When the wireless power transmitting apparatus responds with an ACK, it is confirmed that the retransmission of the first ADT data packet (ADT_PRx(1)) was successful, and the wireless power receiving apparatus transmits a second ADT data packet (ADT_PRx(2)). After repeating this ADT packet transmission sequence, the wireless power transmitting apparatus successfully transmits the last remaining ADT data packet (ADT_PRx) and then receives an ACK. In response, the wireless power receiving apparatus successfully transmits an EOD and receives an ACK, thereby ending the transmission of the authentication response message.

[0460] Fig. 75 is a diagram illustrating an exchange sequence of ADT data packets for an authentication response message according to another embodiment. The embodiment of Fig. 75 differs from the embodiment of Fig. 75 in that the wireless power receiving apparatus divides the authentication response message of a total of 99 bytes into a 16-byte zeroth ADT data packet (ADT_PRx(0)), a 16-byte first ADT data packet (ADT_PRx(1)), ..., a 16-byte fifth ADT data packet (ADT_PRx(5)), and a 3-byte sixth ADT data packet (ADT_PRx(6)) and transmits the divided messages. The header of each ADT data packet is toggled (Header A<->Header B) according to Rule 3, and when the first ADT data packet is retransmitted, the same header used previously (Header B in Fig. 75) is used to perform simplified synchronization and instruct retransmission.

[0461] Fig. 76 is a diagram illustrating an exchange sequence of ADT data packets related to an authentication response message according to yet another embodiment. The embodiment of Fig. 76 differs from the embodiment of Fig. 75 in that the wireless power receiving apparatus divides the authentication response message of a total of 99 bytes into a 16-byte zeroth ADT data packet (ADT_PRx(0)), a 16-byte first ADT data packet (ADT_PRx(1)), ..., a 16-byte fifth ADT data packet (ADT_PRx(5)), and a 3-byte sixth ADT data packet (ADT_PRx(6)) and transmits the divided messages. When transmission of the first ADT data packet (ADT_PRx(1)) fails, the header of the first ADT data packet (ADT_PRx(1)) is retransmitted with its header toggled, even though the header should not be toggled.

[0462] 77 is a diagram illustrating an exchange sequence of ADT data packets for an authentication response message according to yet another embodiment. The embodiment of Fig. 77 illustrates a scenario in which the wireless power receiving apparatus divides an authentication response message of a total of 99 bytes into a 16-byte zeroth ADT data packet (ADT_PRx(0)), a 16-byte first ADT data packet (ADT_PRx(1)), ..., a 16-byte fifth ADT data packet (ADT_PRx(5)), and a 3-byte sixth ADT data packet (ADT_PRx(6)), and transmits the divided message. The scenario illustrates a scenario in which the transmission of the zeroth ADT data packet (ADT_PRx(0)) is successful, but there is no response to the first 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 transmitting device and the wireless power receiving device can simultaneously operate as authentication initiators.

[0465] For example, the wireless power transmitting apparatus may transmit an ADT including an authentication-related packet instead of an ADT including an ACK for a packet received from the wireless power receiving apparatus. In this case, the wireless power receiving apparatus may implicitly regard the ADT including the authentication-related packet as having received an ACK and perform the following operation. That is, when the wireless power transmitting apparatus transmits an ADT including data (authentication-related packet), the wireless power receiving apparatus may determine that the ADT data it previously transmitted to the wireless power transmitting apparatus was successfully transmitted, even if it receives a data ADT instead of an ACK. However, the wireless power transmitting apparatus may transmit a NACK if a communication error occurs in the ADT data previously received from the wireless power receiving apparatus. Of course, the ADT including the authentication-related packet may further include an ACK.

[0466] As another example, the wireless power receiving apparatus may transmit an ADT including an authentication-related packet instead of an ADT including an ACK for a packet received from the wireless power transmitting apparatus. In this case, the wireless power transmitting apparatus may implicitly regard the ADT including the authentication-related packet as having received an ACK and perform the following operation. That is, when the wireless power receiving apparatus transmits an ADT including data (authentication-related packet), even if the wireless power transmitting apparatus receives a data ADT instead of an ACK, it may determine that the ADT data it previously transmitted to the wireless power receiving apparatus was successfully transmitted. Of course, the ADT including the authentication-related packet may further include an ACK.

[0467] 2-4) Communication initiation protocol for wireless power transmitter

[0468] While the wireless power transmitter operates as a slave according to Rule 1, the wireless power receiver can provide an opportunity for PTx initiated communication by the wireless power transmitter 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 a packet to transmit by regularly polling the wireless power transmitter. In this case, the GRP can be used as shown in FIG. 78. As shown in FIG. 78, for example, the wireless power receiver can perform polling by setting the 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 is ready to transmit any type of packet it wishes to transmit.

[0469] Meanwhile, as another method for ensuring more opportunities for communication initiated by the wireless power transmitter, the wireless power transmitter can transmit a request for communication (RFC) bit pattern in response to the RPP (except for mode '100'b) of the wireless power receiver. When the wireless power receiver receives the RFC response, it polls the wireless power transmitter using the GRP at a timing suitable for itself. Although the wireless power receiver does not know exactly when the value of the target power managed by the wireless power transmitter will change, the RFC response of the wireless power transmitter can relatively well guarantee the communication start time desired by the wireless power transmitter.

[0470] In particular, the response deadline polling of the RFC can be used for PTx-initiated power management, which allows the wireless power transmitter to change (increase or decrease) the target power in consideration of the current surrounding charging conditions.

[0471] FIG. 79 is a transmission sequence for power management initiated by a wireless power transmission device according to one embodiment.

[0472] As shown in Fig. 79, the wireless power transmitting apparatus transmits an alarm including an RFC response (bit pattern) to the wireless power receiving apparatus in response to the RPP (mode 0) of the wireless power receiving apparatus. The wireless power receiving apparatus transmits a GRP with a request value set to "0xFF" to the wireless power transmitting apparatus. Thereafter, the wireless power transmitting apparatus transmits a target power packet to the wireless power receiving apparatus. The wireless power receiving apparatus can adjust its operating mode according to the changed target power.

[0473] 6. Applications related to authentication procedures

[0474] The authentication function is set to On / Off by the user. For example, a smartphone can activate or deactivate the authentication function by displaying activation / deactivation of the authentication function to the user through an application, and the user can input selection information regarding activation (ON) or deactivation (OFF).

[0475] The wireless power transmitting and receiving device can provide a very convenient user experience and interface (UX / UI). That is, a smart wireless charging service can be provided, and the smart wireless charging service can be realized based on the UX / UI of a smartphone that includes the wireless power transmitting device. For such applications, the interface between the smartphone's processor and the wireless charging receiving device allows "drop and play" bidirectional communication between the wireless power transmitting device and the receiving device.

[0476] For example, a user may experience a smart wireless charging service at a hotel. When the user enters a hotel 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. During this process, the wireless charger transmits information about the smart wireless charging service to the smartphone. When the smartphone detects that it is located on the wireless charger, detects the reception of wireless power, or receives information about the smart wireless charging service from the wireless charger, the smartphone enters a state in which it asks the user for consent (opt-in) to additional features. To this end, the smartphone may display a message on the screen with or without an audible alarm. An example of the message may include a phrase such as, "Welcome to ### hotel. Select "Yes" to activate smart charging functions: Yes | No Thanks." If the user selects Yes or No Thanks, 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 the wireless charger then perform the smart charging function.

[0477] The smart wireless charging service can also include receiving auto-filled WiFi credentials, for example, the wireless charger sending WiFi credentials to the smartphone, and the smartphone running an appropriate app to automatically fill in the WiFi credentials received from the wireless charger.

[0478] The smart wireless charging service may also include running a hotel application that offers hotel promotions or obtaining 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 a vehicle and places a smartphone on a wireless charger, 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 detects that it is placed on the wireless charger, detects the reception of wireless power, or receives information about the smart wireless charging service from the wireless charger, the smartphone enters a state in which it queries the user for identity verification.

[0480] In this state, the smartphone automatically connects to the vehicle via Wi-Fi and / or Bluetooth. The smartphone can display a message on the screen with or without an alarm sound. An example of the message may include a phrase such as, "Welcome to your car. Select 'Yes' to synchronize device with in-car controls: Yes | No Thanks." If the user selects Yes or No Thanks and inputs it, 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 the wireless charger can then operate the in-vehicle application / display software to perform in-vehicle smart control functions together. The user can enjoy desired music and view the correct map location. The in-vehicle application / display software may include the ability to provide synchronized access for passersby.

[0481] As another example, a user can experience smart wireless charging at home. When a user enters a room and places a smartphone on a wireless charger, 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 detects that it is placed on a wireless charger, detects the reception of wireless power, or receives information about the smart wireless charging service from the wireless charger, the smartphone enters a state in which it asks the user for consent (opt-in) to additional features. To this end, the smartphone can display a message on the screen with or without an audible alarm. An example of the message may include a phrase such as, "Hi xxx, Would you like to activate night mode and secure the building? : Yes | No Thanks." If the user selects Yes or No Thanks, 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 the wireless charger can at least recognize the user's patterns and recommend the user to close doors and windows, turn off the fire, or set an alarm.

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

[0483] The above description merely exemplifies the technical concept of the present invention, and various modifications and variations are possible within the scope of the essential characteristics of the present invention, if one skilled in the art can make such modifications and variations. Therefore, the above-described embodiments of the present invention may be realized separately or in combination with each other.

[0484] Therefore, the embodiments disclosed in the present invention are for illustrative purposes only and are not intended to limit the technical idea of ​​the present invention. The scope of protection of the present invention should be interpreted by the scope of the claims, and all technical ideas within the equivalent range should be interpreted as being included in the scope 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 by forming a magnetic coupling with the wireless power receiving device; a communication / control unit configured to communicate with the wireless power receiving device and control the wireless power; The wireless power transmission device includes: When the wireless power transmitting apparatus has data to send to the wireless power receiving apparatus, transmitting a bit pattern to the wireless power receiving apparatus to request communication initiated by the wireless power transmitting apparatus; receiving, from the wireless power receiving device, a packet for polling the data to be transmitted in response to the bit pattern; configured to transmit a data stream to the wireless power receiving device based on receiving the packet for polling; the data stream comprises a sequence of auxiliary data transports (ADT) packets; The sequence of ADT packets is located after the start of a start of data transport (SOD) packet, The SOD packet defines the start of the data stream.

2. The wireless power transmitter of claim 1 , wherein the bit pattern and the packets for polling are each 8 bits.

3. A method for transmitting wireless power from a wireless power transmitting device to a wireless power receiving device, comprising: transmitting a bit pattern to the wireless power receiving device as a data packet requesting communication initiated by the wireless power transmitting device when the wireless power transmitting device has data to transmit to the wireless power receiving device; receiving a packet for polling the data transmitted from the wireless power receiving device in response to the bit pattern; and transmitting a data stream to the wireless power receiving device based on receiving the packet for polling; the data stream comprises a sequence of auxiliary data transports (ADT) packets; The sequence of ADT packets is located after the start of a start of data transport (SOD) packet, The SOD packet defines the beginning of the data stream.

4. 4. The method of claim 3, wherein said bit pattern and said packets for polling are 8 bits each.

5. A wireless power receiving device, a power pickup unit that forms a magnetic coupling with a wireless power transmission device to receive wireless power from the wireless power transmission device; a communication / control unit that communicates with the wireless power transmitting device and controls the wireless power; The wireless power receiving device includes: receiving a digital ping from the wireless power transmission device; receiving, from the wireless power transmitting device, a bit pattern that requests communication initiated by the wireless power transmitting device when the wireless power transmitting device has data to transmit to the wireless power receiving device; Transmitting a packet in response to the bit pattern to poll the data for transmission to the wireless power transmission device; configured to receive a data stream from the wireless power transmission device based on transmitting the packet for polling; the data stream comprises a sequence of auxiliary data transports (ADT) packets; The sequence of ADT packets is located after the start of a start of data transport (SOD) packet, The SOD packet defines the start of the data stream.

6. The wireless power receiving apparatus according to claim 5 , wherein the bit pattern and the packet each have 8 bits.

7. 1. A method for receiving wireless power from a wireless power transmitting device, the method being performed by a wireless power receiving device, the method comprising: receiving, from the wireless power transmitting device, a bit pattern for requesting communication initiated by the wireless power transmitting device when the wireless power transmitting device has data to transmit to the wireless power receiving device; transmitting a packet for polling the data to be transmitted to the wireless power transmission device in response to the bit pattern; receiving a data stream from the wireless power transmission device based on transmitting the packet for polling; the data stream comprises a sequence of auxiliary data transports (ADT) packets; The sequence of ADT packets is located after the start of a start of data transport (SOD) packet, The SOD packet defines the beginning of the data stream.

8. 8. The method of claim 7, wherein the bit pattern and the packet are each 8 bits.

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