Method and apparatus for high-speed FSK communication in wireless power transmission systems

Abstract

The present disclosure provides a method of transferring wireless power to a wireless power receiver, performed by a wireless power transmitter in a wireless power transmission system, comprising: entering a power transfer phase related to transferring the wireless power; and transmitting an auxiliary data transport (ADT) packet to the wireless power receiver in the power transfer phase, wherein the wireless power transmitter transmits the ADT packet to the wireless power receiver based on Frequency Shift Keying (FSK), and a maximum size of the ADT packet is determined based on a number of cycles used in the FSK; and an apparatus using the same, characterized in that the method and an apparatus using the same.

Description

Technical Field

[0001] This specification relates to wireless power transmission.

Background Art

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

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

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

[0005] On the other hand, this specification provides a method and apparatus for increasing the size of ADT packets and defining a maximum size. [Overview of the Initiative] [Means for solving the problem]

[0006] According to the method and / or apparatus described herein, the wireless power transmitter transmits the ADT packets to the wireless power receiver based on FSK (Frequency Shift Keying), and the maximum size of the ADT packets can be determined based on the number of cycles used in the FSK.

[0007] According to this specification, the maximum ADT size can be increased, and the communication speed can be increased.

[0008] The effects obtained by a specific example in this specification are not limited to those listed above. For example, there may be a variety of technical effects that a person having ordinary skill in the related art can understand or derive from this specification. Thus, the specific effects of this specification are not limited to those explicitly stated herein, but may include a variety of effects that can be understood or derive from the technical features of this specification. [Brief explanation of the drawing]

[0009] [Figure 1] This is a block diagram of a wireless power system 10 according to one embodiment. [Figure 2] This is a block diagram of a wireless power system 10 according to another embodiment. [Figure 3] This document illustrates various examples of electronic devices that incorporate wireless power transmission systems. [Figure 4] This is a block diagram of a wireless power transmission system according to one embodiment. [Figure 5] This figure shows an example of a Bluetooth communication architecture to which one embodiment of this specification can be applied. [Figure 6] This is a block diagram illustrating an example of a wireless power transmission system using BLE communication. [Figure 7] This block diagram shows a wireless power transmission system using BLE communication as another example. [Figure 8] This is a state transition diagram used to explain the wireless power transmission process. [Figure 9] This provides a schematic example of a pin phase 810 protocol. [Figure 10] This provides a schematic example of a protocol for configuration phase 820. [Figure 11] This diagram shows the message field of a configuration packet (CFG) of a wireless power receiving device according to one embodiment. [Figure 12] It is a flowchart schematically showing a protocol of a negotiation stage or a renegotiation stage according to an embodiment. [Figure 13] It is a drawing showing a message field of a performance packet (CAP) of a wireless power transmission device according to an embodiment. [Figure 14] It schematically shows a flowchart of a data flow for a power transmission phase 840 in a baseline protocol. [Figure 15] It schematically shows a flowchart of a data flow for a power transmission phase 840 in an extended protocol. [Figure 16] It shows an application-level data stream between a wireless power transmission device 100 and a wireless power reception device 200 according to an example. [Figure 17] It shows a power control method according to an embodiment. [Figure 18] It schematically shows the structure of an MPP ID packet. [Figure 19] It schematically shows an example of an XID packet in MPP. [Figure 20] It schematically shows a protocol in an MPP restricted mode. [Figure 21] It schematically shows a protocol in an MPP full mode. [Figure 22] It schematically shows a protocol in an MPP full mode. [Figure 23] It schematically shows an example of differential bi-phase encoding. [Figure 24] It schematically shows an example of an asynchronous serial format. [Figure 25] It schematically shows an example of the structure of a data packet. [Figure 26] It schematically shows an example of a header type and the size of a message corresponding thereto. [Figure 27] It schematically shows an example of an ADT packet. [Figure 28] It is a sequence diagram of a method for transmitting wireless power according to an embodiment of this specification. [Figure 29] It is an example summarizing the sizes of ADT packets up to 7 bytes. [Figure 30] It is an example summarizing the sizes of ADT packets larger than 7 bytes. [Figure 31] It schematically shows an example for the CE (control error) interval. [Figure 32] It shows an example of data communication from a wireless power receiver to a wireless power transmitter. [Figure 33] It shows an example of data communication from a wireless power transmitter to a wireless power receiver. [Figure 34] It is the result of simulating an example of ADT transmission using 512 Cycles-based FSK. [Figure 35] It is the result of simulating an example of ADT transmission using 256 Cycles-based FSK. [Figure 36] It is a sequence diagram of a method for transmitting wireless power, showing the example of FIG. 28 in another form. [Figure 37] It is a sequence diagram of a method for transmitting wireless power from the perspective of a wireless power transmitter according to an embodiment of this specification. [Figure 38] It is a sequence diagram of a method for receiving wireless power from the perspective of a wireless power receiver according to an embodiment of this specification.

Mode for Carrying Out the Invention

[0010] In this specification, “A or B” can mean “A only,” “B only,” or “both A and B.” Alternatively, in this specification, “A or B” can be interpreted as “A and / or B.” For example, in this specification, “A, B or C” can mean “A only,” “B only,” “C only,” or “any combination of A, B and C.”

[0011] In this specification, slashes ( / ) and commas can mean "and / or". For example, "A / B" can mean "A and / or B". Thus, "A / B" can mean "A only", "B only", or "both A and B". For example, "A, B, C" can mean "A, B or C".

[0012] In this specification, “at least one of A and B” can mean “A only,” “B only,” or “both A and B.” Furthermore, in this specification, the expressions “at least one of A or B” and “at least one of A and / or B” can be interpreted in the same way as “at least one of A and B.”

[0013] Furthermore, in this specification, “at least one of A, B and C” may mean “A only,” “B only,” “C only,” or “any combination of A, B and C.” Also, “at least one of A, B or C” or “at least one of A, B and / or C” may mean “at least one of A, B and C.”

[0014] Furthermore, parentheses used in this specification can mean "for example." Specifically, when "control information (PDCCH)" is used, "PDCCH" is proposed as an example of "control information." Alternatively, "control information" in this specification is not limited to "PDCCH," but rather "PDCCH" is proposed as an example of "control information." Similarly, when "control information (i.e., PDCCH)" is used, "PDCCH" is proposed as an example of "control information."

[0015] In this specification, technical features described individually within a single drawing may be embodied individually or simultaneously. The term “wireless power” as used below refers to any form of energy associated with electric, magnetic, or electromagnetic fields transmitted from a wireless power transmitter to a wireless power receiver without the use of physical electromagnetic conductors. Wireless power, also known as a wireless power signal, can mean an oscillating magnetic flux enclosed by a primary and secondary coil. For example, power conversion in a system for wirelessly charging devices including mobile phones, cordless phones, iPods®, MP3 players, and headsets is described here. Generally, the basic principles of wireless power transmission include, for example, methods of transmitting power via magnetic coupling, radio frequency (RF), microwaves, and ultrasound.

[0016] Figure 1 is a block diagram of a wireless power system 10 according to one embodiment.

[0017] Referring to Figure 1, the wireless power system 10 includes a wireless power transmitter 100 and a wireless power receiver 200.

[0018] The wireless power transmitter 100 generates a magnetic field by receiving power from an external power source (S). The wireless power receiver 200 receives power wirelessly by generating an electric current using the generated magnetic field.

[0019] Furthermore, in the wireless power system 10, the wireless power transmitter 100 and the wireless power receiver 200 can send and receive various information necessary for wireless power transmission. Here, communication between the wireless power transmitter 100 and the wireless power receiver 200 can be performed by either in-band communication, which utilizes the magnetic field used for wireless power transmission, or out-band communication, which utilizes a separate communication carrier. Out-band communication is also called out-of-band communication. Hereafter, the term out-band communication will be used consistently. Examples of out-band communication include NFC, Bluetooth (registered trademark), and BLE (Bluetooth Low Energy).

[0020] Here, the wireless power transmitter 100 can be provided in a fixed or mobile form. Examples of fixed forms include being embedded in the ceiling or wall or furniture such as a table indoors, being implanted outdoors in a parking lot, bus stop or subway station, or being installed on a means of transport such as a vehicle or train. A mobile wireless power transmitter 100 can be embodied as a mobile device of a movable weight and size, or as part of another device, such as a notebook computer cover.

[0021] Furthermore, the wireless power receiving device 200 must be interpreted as a comprehensive concept that includes various electronic devices equipped with batteries and various home appliances that are powered wirelessly instead of using power cables. Typical examples of wireless power receiving devices 200 include portable terminals, cellular phones, smartphones, personal digital assistants (PDAs), portable media players (PMPs), Wibro terminals, tablets, phablets, notebooks, digital cameras, navigation terminals, televisions, and electric vehicles (EVs).

[0022] Figure 2 is a block diagram of a wireless power system 10 according to another embodiment.

[0023] Referring to Figure 2, in the wireless power system 10, there is one or more wireless power receivers 200. Although Figure 1 shows a one-to-one power exchange between the wireless power transmitter 100 and the wireless power receiver 200, as shown in Figure 2, it is also possible for one wireless power transmitter 100 to transmit power to multiple wireless power receivers 200-1, 200-2, ..., 200-M. In particular, when wireless power transmission is performed using a magnetic resonance method, one wireless power transmitter 100 can simultaneously transmit power to multiple wireless power receivers 200-1, 200-2, ..., 200-M by applying simultaneous transmission or time-division transmission methods.

[0024] Furthermore, although Figure 1 shows a method in which the wireless power transmitter 100 directly transmits power to the wireless power receiver 200, a separate wireless power transceiver or repeater may be provided between the wireless power transmitter 100 and the wireless power receiver 200 to increase the wireless power transmission distance. In this case, power is transmitted from the wireless power transmitter 100 to the wireless power transceiver, and the wireless power transceiver can then transmit power back to the wireless power receiver 200.

[0025] Hereinafter, the terms "wireless power receiver," "power receiver," and "receiver" as used herein refer to the wireless power receiving device 200. Similarly, the terms "wireless power transmitter," "power transmitter," and "transmitter" as used herein refer to the wireless power receiving and transmitting device 100.

[0026] Figure 3 shows various examples of electronic devices into which a wireless power transmission system is implemented.

[0027] Figure 3 shows a classification of electronic devices based on the amount of power transmitted and received by the wireless power transmission system. Referring to Figure 3, low-power (approximately 5W or less or approximately 20W or less) wireless charging methods can be applied to wearable devices such as smart watches, smart glasses, HMDs (Head Mounted Displays), and smart rings, as well as mobile electronic devices (or portable electronic devices) such as earphones, remote controls, smartphones, PDAs, and tablet PCs.

[0028] Medium- and small-sized home appliances such as notebooks, robotic vacuum cleaners, TVs, audio equipment, and monitors can be charged using a medium-power (approximately 50W or less or approximately 200W or less) wireless charging method. Kitchen appliances such as blenders, microwave ovens, and electric rice cookers, as well as personal mobility devices (or electronic devices / means of transportation) such as wheelchairs, electric scooters, electric bicycles, and electric vehicles, can be charged using a high-power (approximately 2kW or less or 22kW or less) wireless charging method.

[0029] The aforementioned electronic devices / mobile devices (or those shown in Figure 1) may each include a wireless power receiver, which will be described later. Therefore, the aforementioned electronic devices / mobile devices can be charged by receiving power wirelessly from a wireless power transmitter.

[0030] The following description will focus on mobile devices to which wireless power charging is applied, but this is merely an example, and the wireless charging method described herein can be applied to the various electronic devices mentioned above.

[0031] Standards for wireless power transmission include those of the WPC (Wireless Power Consortium), AFA (Air Fuel Alliance), and PMA (Power Matters Alliance).

[0032] The WPC standard defines a baseline power profile (BPP) and an extended power profile (EPP). The BPP pertains to wireless power transmitters and receivers that support 5W of power transmission, while the EPP pertains to wireless power transmitters and receivers that support power transmission in the range of greater than 5W and less than 30W.

[0033] A variety of wireless power transmitters and receivers using different power levels are covered by each standard and can be classified into different power classes or categories.

[0034] For example, WPC classifies wireless power transmitters and receivers into power class (PC)-1, PC0, PC1, and PC2, and provides standard documentation for each PC. The PC-1 standard concerns wireless power transmitters and receivers that provide guaranteed power of less than 5W. Applications of PC-1 include wearable devices such as smartwatches.

[0035] The PC0 standard relates to wireless power transmitters and receivers that provide a guaranteed power of 5W. The PC0 standard includes EPP, which provides a guaranteed power of up to 30W. In-band (IB) communication is the mandatory communication protocol for PC0, and out-band (OB) communication can also be used as an optional backup channel. Wireless power receivers can identify whether they support OB by setting an OB flag in a configuration packet. Wireless power transmitters that support OB can enter the OB handover phase by sending a bit pattern for OB handover in response to the configuration packet. The response to the configuration packet is NAK, ND, or a newly defined 8-bit pattern. PC0 applications include smartphones.

[0036] The PC1 standard relates to wireless power transmitters and receivers providing guaranteed power of 30W to 150W. OB is the essential communication channel for PC1, and IB is used for initialization and link establishment to OB. The wireless power transmitter can enter the OB handover phase using a bit pattern for OB handover in response to a configuration packet. PC1 applications include laptops and power tools.

[0037] The PC2 standard relates to wireless power transmitters and receivers that provide guaranteed power of 200W to 2kW, and its applications include kitchen appliances.

[0038] In this way, PCs can be distinguished by their power levels, and supporting compatibility between the same PCs is either optional or mandatory. Here, compatibility between the same PCs means that power can be transmitted and received between the same PCs. For example, if a wireless power transmitter, which is PCx, can charge a wireless power receiver that has the same PCx, then compatibility between the same PCs can be 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, which is PCx, can charge a wireless power receiver that has PCy, then compatibility between different PCs can be maintained.

[0039] Supporting PC compatibility is a crucial issue from both a user experience and infrastructure construction perspective. However, maintaining PC compatibility presents numerous technical challenges, as outlined below.

[0040] In the case of compatibility between devices of the same PC type, for example, a laptop-charging wireless power receiver, which can only reliably charge when power is transmitted continuously, will have problems receiving a stable power supply from a wireless power transmitter of the same PC type, even if the transmitter is of the same PC type, when the transmitter uses an electric tool type that transmits power discontinuously. Also, in the case of compatibility between devices of different PC types, for example, if a wireless power transmitter with a minimum guaranteed power of 200W transmits power to a wireless power receiver with a maximum guaranteed power of 5W, there is a risk of the receiver being damaged due to overvoltage. As a result, PCs are difficult to define as a representative / indicating indicator / standard for compatibility.

[0041] Wireless power transmitters and receivers can provide a considerably convenient user experience and interface (UX / UI). Specifically, a smart wireless charging service can be provided. This smart wireless charging service can be implemented based on the UX / UI of a smartphone, including the wireless power transmitter. For such applications, the interface between the smartphone's processor and the wireless charging receiver allows for "drop-and-play" bidirectional communication between the wireless power transmitter and receiver.

[0042] As an example, a user can experience a smart wireless charging service at a hotel. When the user enters their hotel room and places their smartphone on the room's wireless charger, the wireless charger transmits wireless power to the smartphone, and the smartphone receives the wireless power. In this process, the wireless charger transmits information about the smart wireless charging service to the smartphone. When the smartphone detects that it is located on the wireless charger, or detects that it has received wireless power, or when the smartphone receives information about the smart wireless charging service from the wireless charger, the smartphone enters a state where it asks the user to consent to additional features (opt-in). To this end, the smartphone can display a message on the screen, with or without an alarm. An example message may include text such as, "Welcome to ### hotel. Select "Yes" to activate smart charging functions: Yes | No Thanks." The smartphone receives the user's input to select Yes or No Thanks and performs the next step selected by the user. If Yes is selected, the smartphone transmits the relevant information to the wireless charger. Then, the smartphone and wireless charger work together to perform the smart charging function.

[0043] Furthermore, smart wireless charging services may include those that receive Wi-Fi credentials automatically. For example, a wireless charger could send Wi-Fi credentials to a smartphone, and the smartphone could automatically fill in the Wi-Fi credentials received from the wireless charger by running the appropriate app.

[0044] Furthermore, smart wireless charging services may include running hotel applications that offer hotel promotions, or that retrieve remote check-in / check-out and contact information.

[0045] As another example, a user can experience a smart wireless charging service in a vehicle. When a user gets into the vehicle and places their smartphone on a wireless charger, the wireless charger transmits wireless power to the smartphone, and the smartphone receives the wireless power. In this process, the wireless charger transmits information about the smart wireless charging service to the smartphone. When the smartphone detects that it is located on the wireless charger, or detects that it has received wireless power, or when the smartphone receives information about the smart wireless charging service from the wireless charger, the smartphone enters a state where it requests identity verification from the user.

[0046] In this state, the smartphone automatically connects to the car via Wi-Fi and / or Bluetooth. The smartphone can display messages on its screen, with or without alarms. An example message could include text such as, "Welcome to your car. Select "Yes" to synchronize device with in-car controls: Yes|No Thanks." The smartphone receives user input to select Yes or No Thanks and then performs the next step selected by the user. If Yes is selected, the smartphone sends the corresponding information to the wireless charger. The smartphone and wireless charger can then work together to perform smart control functions in the vehicle by driving the in-vehicle application / display software. The user can enjoy their desired music and check their official map location. The in-vehicle application / display software may include the ability to provide synchronized proximity for pedestrians.

[0047] As another example, a user can experience smart wireless charging in their home. When a user enters a room and places their smartphone on a wireless charger in the room, the wireless charger transmits wireless power to the smartphone, and the smartphone receives the wireless power. In this process, the wireless charger transmits information to the smartphone regarding the smart wireless charging service. When the smartphone detects that it is located on the wireless charger, or detects that it has received wireless power, or when the smartphone receives information regarding the smart wireless charging service from the wireless charger, the smartphone enters a state where it asks the user to consent to additional features (opt-in). To this end, the smartphone can display a message on its screen, with or without an alarm. An example message might include text such as, "Hi xxx, Would you like to activate night mode and secure the building?: Yes|No Thanks." The smartphone receives input from the user to select Yes or No Thanks and performs the next step selected by the user. If Yes is selected, the smartphone transmits the relevant information to the wireless charger. The smartphone and wireless charger can recognize at least the user's patterns and encourage the user to lock doors and windows, turn off power, or set alarms.

[0048] Below, we define a new 'profile' as an indicator / criterion representing / indicating compatibility. That is, it can be interpreted that compatible and stable power transmission / reception are possible between wireless power transceivers having the same 'profile', while power transmission / reception is not possible between wireless power transceivers having different 'profiles'. Profiles can be defined by compatibility and / or application, regardless of (or independently of) power class.

[0049] The profiles can be broadly divided into three categories: i) mobile and computer, ii) power tools, and iii) kitchen.

[0050] Alternatively, the profiles can be broadly divided into four categories: i) mobile, ii) power tools, iii) kitchen, and iv) wearable.

[0051] For the 'Mobile' profile, the PC can be defined as PC0 and / or PC1, the communication protocol / method as IB and OB, and the operating frequency as 87-205kHz. Examples of applications include smartphones and laptops.

[0052] For the 'Power Tools' profile, the PC can be defined as PC1, the communication protocol / method as IB, and the operating frequency as 87-145kHz. Examples of applications can include power tools.

[0053] For the 'Kitchen' profile, the PC can be defined as PC2, the communication protocol / method as NFC-based, and the operating frequency as less than 100kHz. Examples of applications can include kitchen / home appliances.

[0054] For power tools and kitchen profiles, NFC communication can be used between the wireless power transmitter and receiver. The wireless power transmitter and receiver can confirm that they are NFC devices by exchanging WPC NDEF (NFC Data Exchange Profile Format).

[0055] Figure 4 is a block diagram of a wireless power transmission system according to one embodiment.

[0056] Referring to Figure 4, the wireless power transmission system 10 includes a mobile device 450 that receives power wirelessly and a base station 400 that transmits power wirelessly.

[0057] The base station 400 is a device that provides inductive or resonant power and may include at least one power transmitter 100 and a system circuit 405. The power transmitter 100 can transmit and control the transmission of inductive or resonant power. The power transmitter 100 may include a power conversion circuit 110 that converts electrical energy into a power signal by generating a magnetic field through primary coils, and a communications and control circuit 120 that controls communication with and power transmission to the power receiver 200 to transmit power at an appropriate level. The system circuit 405 can perform input power provisioning, control of multiple power transmitters, and other operational controls of the base station 400, such as user interface control.

[0058] The primary coil can generate an electromagnetic field using alternating current (AC) power (or voltage or current). The primary coil receives AC power (or voltage or current) of a specific frequency output from the power conversion circuit 110, thereby generating a magnetic field of a specific frequency. The magnetic field can be generated in a non-radiative or radiative manner, and the wireless power receiver 200 receives it and generates a current. In other words, the primary coil transmits power wirelessly.

[0059] In magnetic induction systems, the primary and secondary coils can take any suitable form, such as copper wire wound around a highly permeable material like ferrite or amorphous metal. The primary coil is sometimes called the transmitting coil, primary core, primary winding, or primary loop antenna. The secondary coil, on the other hand, is sometimes called the receiving coil, secondary core, secondary winding, secondary loop antenna, or pickup antenna.

[0060] When using a magnetic resonance method, the primary and secondary coils can be provided in the form of a primary resonant antenna and a secondary resonant antenna, respectively. The resonant antenna can have a resonant structure including a coil and a capacitor. In this case, the resonant frequency of the resonant antenna is determined by the inductance of the coil and the capacitance of the capacitor. Here, the coil can be in the form of a loop, and a core can be placed inside the loop. The core can be a physical core such as a ferrite core or an air core.

[0061] Energy transmission between a primary and secondary resonant antenna can occur via magnetic resonance. Resonance refers to the phenomenon where, when a near-field corresponding to the resonant frequency is generated in one resonant antenna, and other resonant antennas are located around it, the two resonant antennas are coupled to each other, resulting in highly efficient energy transfer between them. When a magnetic field corresponding to the resonant frequency is generated between the primary and secondary resonant antennas, the primary and secondary resonant antennas resonate with each other. As a result, the magnetic field is directed toward the secondary resonant antenna with higher efficiency than, in general, when the magnetic field generated by the primary resonant antenna is radiated into free space, and therefore, energy can be transmitted from the primary to the secondary resonant antenna with high efficiency. The magnetic induction method can be implemented in a manner 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 distance between the loops must be considerably close.

[0062] Although not shown in the drawings, the wireless power transmitter 100 may further include a communication antenna. The communication antenna can transmit and receive communication signals using communication carriers other than magnetic field communication. For example, the communication antenna can transmit and receive communication signals such as Wi-Fi, Bluetooth, Bluetooth LE, ZigBee®, and NFC.

[0063] The communication / control circuit 120 can send and receive information with the wireless power receiver 200. The communication / control circuit 120 may include at least one of either an IB communication module or an OB communication module.

[0064] An IB communication module can transmit and receive information using magnetic waves with a specific frequency as its center frequency. For example, the communication / control circuit 120 can perform in-band communication by including communication information in the operating frequency of wireless power transmission and transmitting it via the primary coil, or by receiving the operating frequency containing the information via the primary coil. In this case, modulation schemes such as binary phase shift keying (BPSK), frequency shift keying (FSK), or amplitude shift keying (ASK), and coding schemes such as Manchester coding or non-return-to-zero level (NZR-L) coding can be used to include information in the magnetic wave or to interpret the magnetic wave containing the information. Using such IB communication, the communication / control circuit 120 can transmit and receive information over distances of several meters at a data transmission rate of several kbps.

[0065] Out-of-band communication modules can also perform out-of-band communication via a communication antenna. For example, the communication / control circuit 120 can be provided by a near-field communication module. Examples of near-field communication modules include Wi-Fi, Bluetooth, Bluetooth LE, ZigBee, and NFC.

[0066] The communication / control circuit 120 can control the overall operation of the wireless power transmitter 100. The communication / control circuit 120 can perform calculations and processing of various information and control each component of the wireless power transmitter 100.

[0067] The communication / control circuit 120 can be implemented in a computer or similar device using hardware, software, or a combination thereof. In hardware terms, the communication / control circuit 120 can be provided in the form of an electronic circuit that processes electrical signals to perform control functions, and in software terms, it can be provided in the form of a program that drives the hardware communication / control circuit 120.

[0068] The communication / control circuit 120 can control the transmitted power by controlling the operating point. The operating point to be controlled can be a combination of frequency (or phase), duty cycle, duty ratio, and voltage amplitude. The communication / control circuit 120 can control the transmitted power by adjusting at least one of the frequency (or phase), duty cycle, duty ratio, and voltage amplitude. In addition, the wireless power transmitter 100 can supply a constant power, and the wireless power receiver 200 can control the received power by controlling the resonant frequency.

[0069] On the other hand, in a WPC system, the wireless power transmitter 100 can be classified, for example, in terms of power transmission amount. In this case, a wireless power transmitter 100 that supports a maximum wireless power transmission amount of 5W (i.e., a wireless power transmitter 100 that supports the BPP protocol) can be classified, for example, into type A wireless power transmitter 100 and type B wireless power transmitter 100, and a wireless power transmitter 100 that supports a maximum wireless power transmission amount of 15W (i.e., a wireless power transmitter 100 that supports the EPP protocol) can be classified, for example, into type MP-A wireless power transmitter 100 and type MP-B wireless power transmitter 100.

[0070] - Type A and Type MP A wireless power transmitter 100

[0071] A Type A and Type MP A wireless power transmitter 100 may have one or more primary coils. Since a Type A and Type MP A wireless power transmitter 100 activates a single primary coil at a time, a single primary cell matching the activated primary coil may be used.

[0072] -Type B and Type MP B wireless power transmitter 100

[0073] Type B and Type MP B power transmitters may have a primary coil array. Furthermore, Type B and Type MP B power transmitters can enable free positioning. To this end, Type B and Type MP B power transmitters can activate one or more primary coils in the array to realize primary cells at other locations on the interface surface.

[0074] The mobile device 450 includes a power receiver 200 that receives wireless power via a secondary coil, and a load 455 that receives and stores the power received by the power receiver 200 and supplies it to the device.

[0075] The wireless power receiver 200 may include a power pickup circuit 210 and a communications and control circuit 220. The power pickup circuit 210 can receive wireless power via a secondary coil and convert it into electrical energy. The power pickup circuit 210 rectifies the AC signal obtained via the secondary coil and converts it into a DC signal. The communications and control circuit 220 can control the transmission and reception (power transfer and reception) of wireless power.

[0076] The secondary coil can receive wireless power transmitted by the wireless power transmitter 100. The secondary coil can receive power by utilizing the magnetic field generated by the primary coil. Here, if a specific frequency is the resonant frequency, a magnetic resonance phenomenon occurs between the primary and secondary coils, allowing for more efficient power transmission.

[0077] On the other hand, although not shown in Figure 4, the communication / control circuit 220 may further include a communication antenna. The communication antenna can transmit and receive communication signals using communication carriers other than magnetic field communication. For example, the communication antenna can transmit and receive communication signals such as Wi-Fi, Bluetooth, Bluetooth LE, ZigBee, and NFC.

[0078] The communication / control circuit 220 can send and receive information with the wireless power transmitter 100. The communication / control circuit 220 may include at least one of either an IB communication module or an OB communication module.

[0079] An IB communication module can transmit and receive information using magnetic waves with a specific center frequency. For example, the communication / control circuit 220 can perform IB communication by embedding information in a magnetic wave and transmitting it via a secondary coil, or by receiving a magnetic wave containing information via a secondary coil. In this case, modulation schemes such as binary phase shift keying (BPSK), frequency shift keying (FSK), or amplitude shift keying (ASK), and coding schemes such as Manchester coding or non-return-to-zero level (NZR-L) coding can be used to embed information in a magnetic wave or to interpret a magnetic wave containing information. Using such IB communication, the communication / control circuit 220 can transmit and receive information over distances of several meters at a data transmission rate of several kbps.

[0080] The OB communication module can also perform out-band communication via a communication antenna. For example, the communication / control circuit 220 can be provided in the short-range communication module.

[0081] Examples of short-range communication modules include Wi-Fi, Bluetooth, Bluetooth LE, ZigBee, and NFC.

[0082] The communication / control circuit 220 can control the overall operation of the wireless power receiver 200. The communication / control circuit 220 can perform calculations and processing of various information and control each component of the wireless power receiver 200.

[0083] The communication / control circuit 220 can be implemented in a computer or similar device using hardware, software, or a combination thereof. Hardware-wise, the communication / control circuit 220 can be provided in the form of an electronic circuit that processes electrical signals to perform control functions; software-wise, it can be provided in the form of a program that drives the hardware-based communication / control circuit 220.

[0084] If the communication / control circuit 120 and the communication / control circuit 220 are Bluetooth or Bluetooth LE as OB communication modules or short-range communication modules, then the communication / control circuit 120 and the communication / control circuit 220 can be implemented and operated with the communication architecture shown in Figure 5.

[0085] Figure 5 shows an example of a Bluetooth communication architecture to which one embodiment of this specification can be applied.

[0086] Referring to Figure 5, (a) in Figure 5 shows an example of a Bluetooth BR (Basic Rate) / EDR (Enhanced Data Rate) protocol stack that supports GATT, and (b) shows an example of a Bluetooth LE (Low Energy) protocol stack.

[0087] Specifically, as shown in Figure 5(a), the Bluetooth BR / EDR protocol stack may include an upper controller stack 460 and a lower host stack 470, relative to the host controller interface (HCI, 18).

[0088] The host stack (or host module) 470 refers to a wireless transceiver module that receives 2.4GHz Bluetooth signals and hardware for transmitting or receiving Bluetooth packets, and the controller stack 460 is connected to the Bluetooth module and controls the Bluetooth module to perform its operations.

[0089] The host stack 470 may include a BR / EDR PHY layer 12, a BR / EDR Baseband layer 14, and a Link Manager layer 16.

[0090] The BR / EDR PHY layer 12 is a layer that transmits and receives 2.4GHz wireless signals, and when GFSK (Gaussian Frequency Shift Keying) modulation is used, it can transmit data by hopping between 79 RF channels.

[0091] The BR / EDR Baseband layer 14 is responsible for transmitting a digital signal, selecting a channel sequence that hops 1400 times per second, and transmitting a time slot of 625us for each channel.

[0092] The link manager layer 16 utilizes LMP (Link Manager Protocol) to control the overall operation of the Bluetooth Connection (link setup, control, security).

[0093] The link manager layer 16 can perform the following functions:

[0094] - Perform ACL / SCO logical transport, logical link setup, and control.

[0095] -Detach: Interrupts the connection and notifies the other device of the reason for the interruption.

[0096] - Perform power control and role switching.

[0097] - Executes security functions (authentication, pairing, encryption).

[0098] The host-controller interface layer 18 provides an interface between the host module and the controller module, enabling the host to provide commands and data to the controller, and the controller to provide events and data to the host.

[0099] The host stack (or host module) 20 includes a Logical Link Control and Adaptive Protocol (L2CAP) 21, an Attribute Protocol 22, a Generic Attribute Profile (GATT) 23, a Generic Access Profile (GAP) 24, and a BR / EDR profile 25.

[0100] The Logical Link Control and Adaptive Protocol (L2CAP) 21 can provide a single bidirectional channel for transmitting data to a specific protocol or profile.

[0101] The aforementioned L2CAP21 can multiplex various protocols and profiles provided at the Bluetooth level.

[0102] Bluetooth BR / EDR's L2CAP utilizes dynamic channels, supports protocol service multiplexer, retransmission, and streaming modes, and provides segmentation and reassembly, per-channel flow control, and error control.

[0103] The General Attribute Profile (GATT) 23 can function as a protocol that describes how the Attribute Protocol 22 is used when configuring a service. For example, the General Attribute Profile 23 can function to define how ATT attributes are grouped together as a service, and can function to describe features associated with a service.

[0104] Therefore, the general attribute profile 23 and the attribute protocol (ATT) 22 can use features to describe the state and services of a device, and to explain how features relate to each other and how they are used.

[0105] The attribute protocol 22 and the BR / EDR profile 25 define the service (profile) that utilizes Bluetooth BR / EDR and the application protocol for exchanging this data, while the Generic Access Profile (GAP) 24 defines device discovery, connection, and security levels.

[0106] As shown in Figure 5(b), the Bluetooth LE protocol stack includes a controller stack 480 capable of handling timing-sensitive radio device interfaces and a host stack 490 capable of handling high-level data.

[0107] First, the controller stack 480 can be embodied using a communication module that may include a Bluetooth wireless device, and a processor module that may include a processing device such as a microprocessor.

[0108] The host stack 490 is part of an OS running on a processor module, or can be realized by instantiation of a package on the OS.

[0109] In some cases, the controller stack and the host stack can operate or run on the same processing device within the processor module.

[0110] The controller stack 480 includes a physical layer (PHY) 32, a link layer 34, and a host controller interface 36.

[0111] The physical layer (PHY, wireless transceiver module) 32 is a layer that transmits and receives 2.4GHz wireless signals and uses a frequency hopping technique consisting of GFSK (Gaussian Frequency Shift Keying) modulation and 40 RF channels.

[0112] The link layer 34, which is responsible for transmitting or receiving Bluetooth packets, uses three advertising channels to perform advertising and scanning functions, then generates a device-to-device connection, and provides the ability to exchange data packets of up to 257 bytes via 37 data channels.

[0113] The host stack may include a Generic Access Profile (GAP) 40, a Logical Link Control and Adaptive Protocol (L2CAP) 41, a Security Manager (SM) 42, an Attribute Protocol (ATT) 440, a Generic Attribute Profile (GATT) 44, a Generic Access Profile 25, and an LT profile 46. However, the host stack 490 is not limited to these and may include a variety of protocols and profiles.

[0114] The host stack uses L2CAP to multiplex various protocols and profiles provided above Bluetooth.

[0115] First, L2CAP (Logical Link Control and Adaptation Protocol) 41 can provide a single bidirectional channel for transmitting data to a specific protocol or profile.

[0116] The L2CAP41 may be capable of multiplexing data between higher-layer protocols, segmenting and reassembling packages, and managing multicast data transmission.

[0117] Bluetooth LE typically uses three fixed channels (one for the signaling channel, one for the Security Manager, and one for the Attribute protocol). Dynamic channels may also be used as needed.

[0118] On the other hand, BR / EDR (Basic Rate / Enhanced Data Rate) primarily uses dynamic channels and supports protocol service multiplexer, retransmission, and streaming modes.

[0119] SM (Security Manager) 42 is a protocol for authenticating devices and providing key distribution.

[0120] ATT (Attribute Protocol) 43 defines rules for accessing data from a remote device in a server-client structure. ATT has the following six message types: Request, Response, Command, Notification, Indication, and Confirmation.

[0121] (1) Request and Response messages: A Request message is a message used to request and transmit specific information from a client device to a server device, and a Response message is a response message to a Request message that can be used to send from a server device to a client device.

[0122] (2) Command message: A message sent from a client device to a server device, primarily to instruct it to perform a specific action, and the server device does not send a response to the Command message to the client device.

[0123] (3) Notification message: A message sent from a server device to a client device for notification purposes, such as an event, and the client device does not send a confirmation message to the server device in response to the notification message.

[0124] (4) Indication and Confirm messages: These are messages sent from the server device to the client device for notification purposes, such as events. Unlike notification messages, the client device sends a confirmation message to the server device in response to the Indication message.

[0125] This specification describes how, when a GATT profile using the attribute protocol (ATT) 43 requests long data, a value for the data length can be sent so that the client can clearly understand the data length, and a characteristic value can be received from the server using a UUID.

[0126] The General Proximity Profile (GAP) 45 is a newly embodied layer for Bluetooth LE technology and is used to control how role selection and multi-profile operation occur for communication between Bluetooth LE devices.

[0127] Furthermore, the general proximity profile 45 is primarily used in the device discovery, connection generation, and security procedure sections, defining a way to provide information to the user and defining the following attribute types.

[0128] (1) Service: Defines the basic operation of the device by combining data and associated behaviors.

[0129] (2) Include: Defines the relationships between services.

[0130] (3) Characteristics: Data values ​​used in the service

[0131] (4) Behavior: A computer-readable format defined by a UUID (Universal Unique Identifier, value type).

[0132] The aforementioned LE profile 46 is a GATT-dependent profile and is mainly applied to Bluetooth LE devices. Examples of LE profiles 46 include Battery, Time, FindMe, Proximity, and Time, and the specific contents of GATT-based profiles are as follows.

[0133] (1) Battery: Battery information exchange method

[0134] (2) Time: Method of exchanging time information

[0135] (3) FindMe: Provides distance-based alarm service

[0136] (4) Proximity: Battery information exchange method

[0137] (5) Time: Method of exchanging time information

[0138] The General Attribute Profile (GATT) 44 may function as a protocol describing how the Attribute Protocol 43 is used when configuring a service. For example, the General Attribute Profile 44 may function to specify how ATT attributes are grouped together as a service, and may function to describe the characteristics associated with the service.

[0139] Therefore, the general attribute profile 44 and the attribute protocol (ATT) 43 can use features to describe the state and services of a device and to explain how features relate to each other and how they are used.

[0140] The following is a brief explanation of the Bluetooth Low Energy (BLE) technology procedure.

[0141] BLE procedures can be divided into procedures such as Device Filtering Procedure, Advertising Procedure, Scanning Procedure, Discovering Procedure, and Connecting Procedure.

[0142] Device Filtering Procedure

[0143] Device filtering procedures are a method to reduce the number of devices in the controller stack that perform responses to requests, instructions, notifications, etc.

[0144] Since not all devices need to respond to a request when it is received, the controller stack can reduce the number of requests sent, thereby reducing power consumption on the BLE controller stack.

[0145] An advertising device or scanning device may perform the device filtering procedure to restrict the devices that receive advertising packets, scan requests, or connection requests.

[0146] Here, an advertising device refers to a device that sends advertising events, that is, a device that executes advertisements, and is also referred to as an advertiser.

[0147] A scanning device refers to a device that performs scanning and sends scan requests.

[0148] In BLE, when a scanning device receives some advertising packets from an advertising device, the scanning device is required to send a scan request to the advertising device.

[0149] However, if a device filtering procedure is used and sending a scan request is unnecessary, the scanning device can ignore the advertising packets sent from the advertising device.

[0150] Device filtering procedures can also be used during the connection request process. If device filtering is used during the connection request process, it becomes unnecessary to send a response to the connection request by ignoring it.

[0151] Advertising Procedure

[0152] The advertising device executes advertising procedures to perform omnidirectional broadcasting to devices within its area.

[0153] Here, undirected advertising is advertising directed at all devices, not specific devices, allowing all devices to scan the advertisement and request additional information or connection.

[0154] In contrast, Directed advertising can scan for advertisements only on devices designated as receiving devices, and then request additional information or connections.

[0155] The advertising procedure is used to establish a Bluetooth connection with a nearby starting device.

[0156] Alternatively, the advertising procedure can be used to provide periodic broadcasts of user data to scanning devices that are listening on advertising channels.

[0157] In the advertising process, all advertisements (or advertising events) are broadcast via physical advertising channels.

[0158] An advertising device can receive scan requests from listening devices that are performing listening in order to obtain additional user data from the advertising device. The advertising device sends a response to the scan request to the device that sent the scan request via the same advertising physical channel that received the scan request.

[0159] Broadcast user data, which is sent as part of an advertising packet, is dynamic data, while scan response data is generally static data.

[0160] An advertising device can receive connection requests from an initiating device on the physical advertising (broadcast) channel. If an advertising device uses an available advertising event and the initiating device is not filtered by the device filtering procedure, the advertising device will stop the advertisement and proceed to connected mode. The advertising device can start advertising again after entering connected mode.

[0161] Scanning Procedure

[0162] A scanning device performs a scanning procedure to listen to an omnidirectional broadcast of user data from an advertising device that uses an advertising physical channel.

[0163] The scanning device sends a scan request to the advertising device via the advertising physical channel to request additional data from the advertising device. The advertising device sends a scan response, which is a response to the scan request, via the advertising physical channel, containing the additional data requested by the scanning device.

[0164] The aforementioned scanning procedure can be used while connecting with other BLE devices via a BLE piconet.

[0165] If the scanning device is in initiator mode, which allows it to receive broadcast advertising events and initiate connection requests, it can initiate a Bluetooth connection with the advertising device by sending a connection request to the advertising device via the physical advertising channel.

[0166] When a scanning device sends a connection request to an advertising device, the scanning device stops initiator mode scanning for additional broadcasts and proceeds to connection mode.

[0167] Discovering Procedure

[0168] Bluetooth-enabled devices (hereinafter referred to as "Bluetooth devices") perform advertising and scanning procedures to discover nearby devices or to be discovered by other devices within a given area.

[0169] The discovery process is performed asymmetrically. A Bluetooth device that attempts to find other devices in its vicinity is called a discovering device, and it listens to find devices advertising scannable advertising events. A Bluetooth device that is discovered and available to other devices is called a discoverable device, and it actively broadcasts advertising events via advertising (broadcast) physical channels so that other devices can scan them.

[0170] Both the discovering device and the discoverable device can already be connected to other Bluetooth devices via piconet.

[0171] Connection procedure

[0172] The connection procedure is asymmetrical, requiring one Bluetooth device to perform an advertising procedure while another Bluetooth device performs a scanning procedure.

[0173] In other words, the advertising procedure can be the objective, and as a result, only one device should respond to the advertisement. After receiving a connectable advertising event from the advertising device, a connection can be initiated by sending a connection request to the advertising device via the advertising (broadcast) physical channel.

[0174] Next, we will briefly explain the operating states in BLE technology, namely the Advertising State, Scanning State, Initiating State, and Connection State.

[0175] Advertising State

[0176] The link layer (LL) enters the advertising state at the instruction of the host (stack). When the link layer is in the advertising state, it sends advertising PDUs (Packet Data Circuits) from advertising events, etc.

[0177] Each ad event consists of at least one ad PDU, which is sent via the ad channel index being used. Once each ad event has been sent via the ad channel index being used, the ad event can be terminated earlier if it is finished or if the ad device needs to make space for other functions to run.

[0178] Scanning State

[0179] The link layer enters a scanning state at the host's (stack's) instruction. While scanning, the link layer listens for the advertising channel index.

[0180] There are two types of scanning states: passive scanning and active scanning, and each scanning type is determined by the host.

[0181] No separate time or advertising channel index is defined for scanning.

[0182] During scanning, the link layer listens for ad channel indices for a scan window duration. The scan interval is defined as the interval between the start points of two consecutive scan windows.

[0183] The link layer must listen for the completion of all scan intervals within a scan window, as instructed by the host, provided there are no scheduling conflicts. Within each scan window, the link layer must scan other ad channel indexes. The link layer uses all available ad channel indexes.

[0184] In passive scanning, the link layer only receives packets and cannot transmit any packets.

[0185] When scanning is active, the link layer listens to ad PDU types that can request ad PDUs and additional ad device-related information from the ad device.

[0186] Initiating State

[0187] The link layer enters the startup state at the instruction of the host (stack).

[0188] When the link layer is in the starting state, it listens to the advertising channel index.

[0189] During the initial state, the link layer listens for the ad channel index during the scan window interval.

[0190] Connection state

[0191] The link layer enters a connected state when a device making a connection request, i.e., the initiating device, sends a CONNECT_REQ PDU to the advertising device, or when the advertising device receives a CONNECT_REQ PDU from the initiating device.

[0192] Once a connection state is entered, it is assumed that the connection is being generated. However, it is not necessary to assume that the connection is established at the moment it enters the connection state. The only difference between a newly generated connection and a pre-established connection is the link-layer connection supervision timeout value.

[0193] When both devices are connected, they perform different roles.

[0194] A link layer that acts as the master is called the master, and a link layer that acts as a slave is called the slave. The master adjusts the timing of connection events, which are the points in time when the master and slave are synchronized.

[0195] The following briefly describes the packets defined in the Bluetooth interface. BLE devices use the packets defined below.

[0196] Packet Format

[0197] The Link Layer has only one packet format used for both advertising channel packets and data channel packets.

[0198] Each packet consists of four fields: the preamble, the connection address (access address), the PDU (Packet Data Unit), and the CRC.

[0199] When a packet is sent from an advertising physical channel, the PDU should be an advertising channel PDU, and when a packet is sent from a data physical channel, the PDU should be a data channel PDU.

[0200] Advertising Channel PDU (Advertising Channel PDU)

[0201] The advertising channel PDU (Packet Data Circuit) has a 16-bit header and payloads of various sizes.

[0202] The PDU type field of the ad channel PDU included in the header indicates the PDU type as defined in Table 1 below.

[0203] [Table 1]

[0204] Advertising PDUs (Advertising PDUs) are the advertising channel PDU types listed below, and are used for specific events.

[0205] ADV_IND: Connectable Omnidirectional Ad Events

[0206] ADV_DIRECT_IND: Connectable directional advertising events

[0207] ADV_NONCONN_IND: Unable to connect to omnidirectional ad event

[0208] ADV_SCAN_IND: Scannable Omnidirectional Ad Event

[0209] The aforementioned PDU is transmitted from the Link Layer in advertising state and received by the Link Layer in scanning state or initiating state.

[0210] Scanning PDU

[0211] The following advertising channel PDU types are called scanning PDUs and are used in the conditions described below.

[0212] SCAN_REQ: Transmitted by the link layer in scanning mode and received by the link layer in advertising mode.

[0213] SCAN_RSP: Transmitted by the link layer in advertising mode, and received by the link layer in scanning mode.

[0214] Initiating PDUs

[0215] The following ad channel PDU types are called start PDUs.

[0216] CONNECT_REQ: Sent by the link layer in the initial state, and received by the link layer in the advertisement state.

[0217] Data Channel PDU

[0218] A data channel PDU can have a 16-bit header, a payload of various sizes, and may include a Message Integrity Check (MIC) field.

[0219] As mentioned above, the procedures, states, packet formats, etc., in BLE technology can be applied to implement the method proposed herein.

[0220] Referring again to Figure 4, the load 455 is a battery. The battery can store energy by utilizing the power output from the power pickup circuit 210. On the other hand, the mobile device 450 does not necessarily have to include a battery. For example, the battery can be provided in the form of a removable external configuration. As another example, the wireless power receiver 200 may include a drive means that drives various operations of the electronic device instead of a battery.

[0221] The mobile device 450 is illustrated to include a wireless power receiver 200, and the base station 400 is illustrated to include a wireless power transmitter 100. However, in a broad sense, the wireless power receiver 200 can be considered identical to the mobile device 450, and the wireless power transmitter 100 can be considered identical to the base station 400.

[0222] If the communication / control circuits 120 and 220 include Bluetooth or Bluetooth LE as an OB communication module or short-range communication module in addition to the IB communication module, the wireless power transmitter 100 including the communication / control circuit 120 and the wireless power receiver 200 including the communication / control circuit 220 can be represented by a simplified block diagram as shown in Figure 6.

[0223] Figure 6 is a block diagram showing an example of a wireless power transmission system using BLE communication.

[0224] Referring to Figure 6, the wireless power transmitter 100 includes a power conversion circuit 110 and a communication / control circuit 120. The communication / control circuit 120 includes an in-band communication module 121 and a BLE communication module 122.

[0225] On the other hand, the wireless power receiving device 200 includes a power pickup circuit 210 and a communication / control circuit 220. The communication / control circuit 220 includes an in-band communication module 221 and a BLE communication module 222.

[0226] In one aspect, the BLE communication modules 122 and 222 perform the architecture and operation shown in Figure 5. For example, the BLE communication modules 122 and 222 may be used to establish a connection between the wireless power transmitter 100 and the wireless power receiver 200, and to exchange control information and packets necessary for wireless power transmission.

[0227] In other aspects, the communication / control circuit 120 may be configured to operate a profile for wireless charging, where the profile for wireless charging may be GATT utilizing BLE transmission.

[0228] Figure 7 is a block diagram showing a wireless power transmission system using BLE communication as another example.

[0229] Referring to Figure 7, the communication / control circuits 120 and 220 each include only the in-band communication modules 121 and 221, respectively, and the BLE communication modules 122 and 222 can be provided separately from the communication / control circuits 120 and 220.

[0230] Hereinafter, a coil or coil section includes a coil and at least one element adjacent to the coil, and may be referred to as a coil assembly, coil cell, or cell.

[0231] On the other hand, when the user places the wireless power receiver 200 within the working space of the wireless power transmitter 100, both the wireless power transmitter 100 and the wireless power receiver 200 begin communicating for the purpose of configuring and controlling power transmission. At this time, the power signal can provide a carrier for all communications, and the protocol for communication can consist of multiple stages. The communication protocol will be described below.

[0232] Figure 8 is a state transition diagram illustrating the wireless power transmission procedure.

[0233] WPC allows for the definition of two communication protocols.

[0234] -Baseline protocol (or BPP): This can refer to the original protocol that supports only one-way communication from the wireless power receiver 200 to the wireless power transmitter 100.

[0235] - Extended protocol (or EPP): Supports bidirectional communication and improved FOD (foreign object detection) functionality, and can also support data transmission stream functionality and authentication options.

[0236] Referring to Figure 8, the power transfer operation between the wireless power transmitter 100 and the wireless power receiver 200 according to one embodiment of this specification can be broadly divided into the ping phase 810, the configuration phase 820, the negotiation phase 830, and the power transfer phase.

[0237] -Pin Phase 810

[0238] At pin phase 810, the wireless power transmitter 100 may attempt to establish communication with the wireless power receiver 200. Before attempting to establish communication, a measurement may be performed to determine whether there are any objects such as bank cards, coins, or other metals that could be damaged or overheated during power transmission. Here, such a measurement may be performed without waking the wireless power receiver 200.

[0239] Here, after obtaining design information from the wireless power transmitter 100, the conclusion regarding whether the detected metal is a foreign object or a friendly metal can be postponed to the negotiation phase 830.

[0240] - Configuration Phase 820

[0241] In configuration phase 820, the wireless power receiver 200 can transmit basic identification and configuration data to the wireless power receiver 200. Both the wireless power transmitter 100 and the wireless power receiver 200 can then use this information to generate a baseline power transfer contract.

[0242] Furthermore, the wireless power transmitter 100 and the wireless power receiver 200 can decide in configuration phase 820 whether to continue with the Baseline Protocol or the Extended Protocol.

[0243] Here, the wireless power receiver 200 can utilize enhanced features such as FOD, data transmission stream, and authentication only when it implements an extended protocol.

[0244] - Negotiation Phase 830

[0245] In negotiation phase 830, the radio power transmitter 100 and the radio power receiver 200 can establish an extended power transfer contract, which includes additional settings and restrictions. The radio power receiver 200 can also provide design information to the radio power transmitter 100. Later, this design information can be used to complete the FOD before switching to power transfer phase 840.

[0246] Here, negotiation phase 830 may correspond to a stage that does not exist in the baseline protocol.

[0247] - Power transmission phase 840

[0248] The power transmission phase 840 may be the stage in which power is transmitted to the load of the wireless power receiver 200.

[0249] In the extended protocol, the wireless power transmitter 100 and the wireless power receiver 200 can perform system calibration when this stage begins. This stage may occasionally be interrupted to renegotiate elements of the power transmission contract, but power transmission may continue during such renegotiations.

[0250] The protocols for the aforementioned Ping Phase (810), Configuration Phase (820), Negotiation Phase (830), and Power Transfer Phase (840) will be explained in more detail below.

[0251] 1. Pin Phase 810

[0252] When pin phase 810 begins, the wireless power transmitter 100 does not yet know whether the wireless power receiver 200 is within the operating volume. Furthermore, the wireless power transmitter 100 cannot recognize the wireless power receiver 200 because the system is generally deactivated due to a lack of power signal.

[0253] In this situation, before the wireless power transmitter 100 initiates a digital pin to request a response from the wireless power receiver 200, the wireless power transmitter 100 may go through the following steps.

[0254] Figure 9 schematically illustrates an example of the pin phase 810 protocol.

[0255] As shown in Figure 9, the wireless power transmitter 100 can perform analog pin operations (S910). That is, the wireless power transmitter 100 can transmit analog pins to determine whether or not an object is present in the operating volume. For example, the wireless power transmitter can sense whether or not an object is present in the operating volume based on a change in the current of the transmitting coil or primary coil.

[0256] The wireless power transmitter 100 can be protected by NFC tag protection (S920). Here, the protection of the NFC tag can be carried out by the following procedure.

[0257] a) First, it can be confirmed whether one or more of the detected objects contain an NFC tag.

[0258] b) Subsequently, in the case of an object containing an NFC tag, it can be confirmed whether it can withstand the power signal without being damaged.

[0259] c) If the wireless power transmitter 100 determines that the NFC tag cannot withstand the power signal, it will hold the pin position without starting the digital pin, and the wireless power transmitter 100 can inform the user of the reason why it will not continue.

[0260] The wireless power transmitter 100 can perform foreign object detection (S930). That is, the wireless power transmitter 100 can collect information useful for determining whether or not there are foreign objects other than the wireless power receiver 200. For this purpose, the wireless power transmitter 100 can use various methods such as the free-power FOD method.

[0261] On the other hand, in the three stages mentioned above (S910, S920, and S930), the wireless power receiver does not need to be operational.

[0262] If the wireless power transmitter 100 has performed the above steps and determines that there is a potential wireless power receiver 200 in the working space, the wireless power transmitter 100 can initiate a digital pin (S940). Here, the digital pin can request a response from the wireless power receiver 200, such as a SIG (signal strength) data packet or an EPT (End Power Transfer) data packet.

[0263] Subsequently, the wireless power transmitter 100 can receive a SIG or EPT from the wireless power receiver 200 (S950). Here, the SIG data packet may provide a measurement of the coupling, and the SIG data packet may contain information regarding the signal strength value. The EPT data packet may provide a power transmission cessation request and the reason for the request.

[0264] If the wireless power transmitter 100 is unable to receive the above-mentioned response from the wireless power receiver 200, the wireless power transmitter 100 can remain in pin phase 810 and repeat the above steps.

[0265] 2. Configuration Phase 820

[0266] The configuration phase 820 is part of the following protocol.

[0267] - The wireless power receiving device 200 can cause the wireless power transmitting device 100 to identify itself.

[0268] - The wireless power receiving device 200 and the wireless power transmitting device 100 can establish a baseline power transmission contract.

[0269] - The wireless power receiving device 200 and the wireless power transmitting device 100 can determine a protocol modification for power transmission.

[0270] In the configuration phase 820, the wireless power transmitting device 100 and the wireless power receiving device 200 can continue to operate using digital pin parameters. This can mean that the power and current levels of both the wireless power transmitting device 100 and the wireless power receiving device 200 are changed only when the user moves the wireless power receiving device 200 within the operating space.

[0271] Hereinafter, the protocol in the configuration phase 820 will be described more specifically.

[0272] FIG. 10 schematically shows an example of the protocol for the configuration phase 820.

[0273] According to FIG. 10, the wireless power transmitting device 100 can receive an ID (identification) from the wireless power receiving device 200 (S1010). Alternatively, the wireless power transmitting device 100 can also receive an XID (extended identification) from the wireless power receiving device 200 (S1020). That is, the wireless power receiving device 200 can identify itself using the ID data packet and optionally the XID data packet.

[0274] The wireless power transmitter 100 can selectively receive PCH (power control hold-off) data packets from the wireless power receiver 200 (S1030), and the wireless power transmitter 100 can receive CFG data packets from the wireless power receiver 200 (S1040). That is, the wireless power receiver 200 can use the PCH and / or CFG data packets to provide data for use in a power transmission contract.

[0275] Finally, the wireless power transmitter 100 can, if possible, verify the extended protocol (S1050).

[0276] Summarizing and organizing each of the data packets mentioned above, we get the following:

[0277] -ID: The ID data packet may contain information that identifies the wireless power receiving device 200. Here, the ID may include a manufacturer code, a basic device identifier, etc. The ID may also include information that identifies the presence or absence of the XID data packet during the configuration phase.

[0278] -XID: The XID data packet may contain additional identification data.

[0279] -PCH: The PCH data packet can constitute a delay between the reception of the CE data packet and the start of coil current adjustment by the radio power transmitter 100.

[0280] -CFG: CFG data packets can provide basic configuration data.

[0281] For example, a CFG data packet can provide all the parameters that recommend power transmission in the baseline protocol. Simultaneously, a CFG data packet can provide all the FSK communication parameters used in the extended protocol. Furthermore, a CFG data packet can provide additional functionality for the wireless power receiver 200.

[0282] Figure 11 is a diagram showing the message field of a configuration packet (CFG) of a wireless power receiving device according to one embodiment.

[0283] As shown in Figure 11, a configuration packet (CFG) according to one embodiment may have a header value of 0x51, and the message field of the configuration packet (CFG) may include a 1-bit authentication (AI) flag and a 1-bit out-of-band (OB) flag.

[0284] The Authentication Flag (AI) indicates whether the wireless power receiver supports authentication functions. For example, a value of "1" for the Authentication Flag (AI) indicates that the wireless power receiver supports authentication functions or can act as an Authentication Initiator, while a value of "0" for the Authentication Flag (AI) indicates that the wireless power receiver does not support authentication functions or cannot act as an Authentication Initiator.

[0285] The Outband (OB) flag indicates whether the radio power receiver supports outband communication. For example, a value of "1" for the Outband (OB) flag indicates that the radio power receiver supports outband communication, while a value of "0" indicates that the radio power receiver does not support outband communication.

[0286] The provision of the aforementioned ID and / or XID is for identification purposes. The provision of the PCH and / or CFG is for the construction of the power transmission contract.

[0287] 3. Negotiation Phase 830

[0288] Negotiation Phase 830 is part of an extended protocol that allows the radio power transmitter 100 and the radio power receiver 200 to modify the power transmission contract. There are two types of this phase.

[0289] - Negotiation Phase 830: The negotiation phase 830 is directly connected after the configuration phase 820 and plays a role in generating an initial extended power transmission contract. At the same time, the negotiation phase 830 also plays a role in completing the pre-power FOD function. Here, the length of the negotiation stage is not limited.

[0290] - Re-negotiation Phase: The re-negotiation phase can interrupt the power transmission phase 840 multiple times and generally plays a role in adjusting a single element of the power transmission contract. Also, the FOD / qf, FOD / rf, and SRQ / rpr data packets may not be used in the re-negotiation stage. The constraints on the CE data packets in the power transmission phase 840 limit the length of the re-negotiation stage.

[0291] During the negotiation phase or the re-negotiation phase, an update of the power transmission contract may be performed to extend or modify the power transmission contract related to the reception / transmission of wireless power between the wireless power receiving device and the wireless power transmitting device, or to adjust at least a part of the elements of the power transmission contract, or an exchange of information for establishing outband communication may be performed.

[0292] FIG. 12 is a flowchart schematically showing the protocol of the negotiation phase or the re-negotiation phase according to an embodiment.

[0293] Referring to FIG. 12, the wireless power transmitting device 100 can receive an FOD status data packet (e.g., FOD) from the wireless power receiving device 200 (S1210). Here, the wireless power receiving device 200 can use the FOD status data packet to inform the wireless power transmitting device 100 of the influence of its presence on the selected attributes of the reference wireless power transmitting device 100. Then, the wireless power transmitting device 100 can configure the FOD function using this information.

[0294] The wireless power transmitting device 100 can transmit an ACK / NAK for the above FOD status data packet to the wireless power receiving device 200 (S1215).

[0295] On the other hand, the wireless power receiver 200 can receive the ID (Identification data packet), CAP (Capabilities data packet), and XCAP (extended CAP) from the wireless power transmitter 100 using GRQ (General Request data packet).

[0296] A General Request Packet (GRQ) may have a header value of 0x07 and may include a 1-byte message field. The message field of the General Request Packet (GRQ) may include the header value of a data packet that the wireless power receiver 200 requests from the wireless power transmitter 100 using the GRQ packet.

[0297] For example, during the negotiation or renegotiation phase, the wireless power receiver 200 can send a GRQ packet (GRQ / id) to the wireless power transmitter 100 requesting an ID packet from the wireless power transmitter 100 (S1220).

[0298] Upon receiving the GRQ / id, the wireless power transmitter 100 can transmit an ID packet to the wireless power receiver 200 (S1225). The ID packet from the wireless power transmitter 100 contains information for the "Manufacturer Code". The ID packet containing information for the "Manufacturer Code" allows the manufacturer of the wireless power transmitter 100 to be identified.

[0299] Alternatively, during the negotiation or renegotiation phase, the wireless power receiver 200 may send a GRQ packet (GRQ / cap) to the wireless power transmitter 100 requesting a performance packet (CAP) from the wireless power transmitter 100 (S1230). The message field of the GRQ / cap may include the header value (0x31) of the performance packet (CAP).

[0300] Upon receiving GRQ / cap, the wireless power transmitter 100 can transmit a performance packet (CAP) to the wireless power receiver 200 (S1235).

[0301] Alternatively, during the negotiation or renegotiation phase, the wireless power receiver 200 may send a GRQ packet (GRQ / xcap) to the wireless power transmitter 100 requesting a performance packet (CAP) from the wireless power transmitter 100 (S1240). The message field of the GRQ / xcap may include the header value (0x32) of the performance packet (XCAP).

[0302] Upon receiving GRQ / xcap, the wireless power transmitter 100 can transmit a performance packet (XCAP) to the wireless power receiver 200 (S1245).

[0303] Figure 13 is a diagram showing the message field of a performance packet (CAP) of a wireless power transmission device according to one embodiment.

[0304] A performance packet (CAP) according to one embodiment may have a header value of 0x31, and as shown in Figure 19, it may also include a 3-byte message field.

[0305] Referring to Figure 13, the message field of a performance packet (CAP) may include a 1-bit authentication (AR) flag and a 1-bit out-of-band (OB) flag.

[0306] The authentication flag (AR) indicates whether the wireless power transmitter 100 supports the authentication function. For example, if the value of the authentication flag (AR) is "1", it indicates that the wireless power transmitter 100 supports the authentication function or can operate as an authentication responder, and if the value of the authentication flag (AR) is "0", it indicates that the wireless power transmitter 100 does not support the authentication function or cannot operate as an authentication responder.

[0307] The Out-of-Band (OB) flag indicates whether the wireless power transmitter 100 supports out-of-band communication. For example, when the value of the Out-of-Band (OB) flag is "1", the wireless power transmitter 100 is instructed to perform out-of-band communication, and when the value of the Out-of-Band (OB) flag is "0", it can be instructed that the wireless power transmitter 100 does not support out-of-band communication.

[0308] During the negotiation phase, the wireless power receiver 200 can receive the performance packet (CAP) of the wireless power transmitter 100 and confirm whether the authentication function support and out-of-band communication support of the wireless power transmitter 100 are available.

[0309] Returning again to FIG. 12, the wireless power receiver 200 can update the elements of the power transfer contract regarding the power provided in the power transmission phase using at least one specific request packet (SRQ, Specific Request data packet) during the negotiation phase or the re-negotiation phase (S1250), and can receive an ACK / NAK for this (S1255).

[0310] On the other hand, in order to confirm the extended power transfer contract and end the negotiation phase, the wireless power receiver 200 transmits SRQ / en to the wireless power transmitter 100 (S1260), and can receive an ACK from the wireless power transmitter 100 (S1265).

[0311] 4. Power Transmission Phase 840

[0312] The power transmission phase 840 is part of the protocol in which actual power is transmitted as the load of the wireless power receiver 200. Here, the power transfer can be performed according to the conditions of the power transfer contract generated in the negotiation phase 830.

[0313] <Power Control Based on CE>

[0314] The wireless power receiver 200 can control the power level by transmitting control error (CE) data to the wireless power transmitter 100, which measures the deviation between the target and the actual operating point of the wireless power receiver 200. The wireless power transmitter 100 and the wireless power receiver 200 aim to make the control error data zero, at which point the system will operate at the target power level.

[0315] <FOD method within power transfer>

[0316] In addition to control error data, the wireless power transmitter 100 and the wireless power receiver 200 can exchange information to facilitate FOD detection. The wireless power receiver 200 periodically reports the amount of power it receives (received power level) to the wireless power transmitter 100, and the wireless power transmitter 100 can inform the wireless power receiver 200 whether or not it has detected a foreign object. Methods available for FOD detection during the power transmission phase include, for example, power loss calculation. In this approach, the wireless power transmitter 100 compares the received power level reported by the wireless power receiver 200 with the amount of transmitted power (transmitted power level), and can send a signal to the wireless power receiver 200 (indicating whether or not it has detected a foreign object) when the difference exceeds a threshold.

[0317] <Renegotiation Phase>

[0318] Depending on the circumstances, if necessary, the wireless power transmitter 100 or the wireless power receiver 200 may request renegotiation of the power transmission contract during the power transmission phase. Examples of modified circumstances in which renegotiation of the power transmission contract may take place are as follows:

[0319] - If the wireless power receiver 200 requires (substantially) more power than previously negotiated.

[0320] - If the wireless power transmitter 100 is detected to be operating at low efficiency.

[0321] - If the wireless power transmitter 100 can no longer maintain the current power level due to the increased operating temperature (or conversely, if the wireless power receiver 200 can operate at a higher power level after it has cooled sufficiently).

[0322] Here, an example of a specific protocol for the renegotiation phase is as described above.

[0323] <Data transmission stream>

[0324] The wireless power transmitter 100 and the wireless power receiver 200 can initiate a data transmission stream and exchange application-level data throughout the entire power transmission phase 840.

[0325] A key common application here is authentication, where both sides can verify each other's credentials using a modulation prevention method. For example, a wireless power receiver 200 might attempt to verify the credentials of a wireless power transmitter 100 to confirm whether it can be trusted to operate safely at high power levels. If the credentials are appropriate, it can mean that the compliance test has been passed.

[0326] Therefore, this specification provides a method for initiating power transmission at a low power level and controlling the power to a higher level only after the authentication protocol has been successfully completed.

[0327] <Protocol in power transmission phase 840>

[0328] The above provides a general overview of the operation between the wireless power transmitter 100 and the wireless power receiver 200 during the power transmission phase 840. To facilitate a smooth understanding of the operation during the power transmission phase 840, the protocols used in this phase will be described separately for the baseline protocol and the extended protocol.

[0329] Figure 14 schematically shows the data flow for power transmission phase 840 in the baseline protocol.

[0330] According to Figure 14, the wireless power receiver 200 can transmit CE to the wireless power transmitter 100 (S1410). Here, the wireless power receiver 200 can normally transmit CE data packets several times per second.

[0331] The wireless power receiver 200 can generally send RP (received power) data packets (RP8 in the baseline protocol) to the wireless power transmitter 100 once every 1.5 seconds (S1420).

[0332] Selectively, the wireless power receiver 200 can transmit CHS (charge status) data packets to the wireless power transmitter 100 (S1430).

[0333] The data packets mentioned above can be summarized and explained as follows:

[0334] -CE: The CE data packet can provide feedback on the desired power level. The CE data packet may include a control error value, which may be a signed integer value that is a relative measurement of the deviation between the actual operating point and the target operating point of the wireless power receiver 200. If the control error value is positive, it indicates that the actual operating point is below the target operating point, and the wireless power transmitter 100 can be requested to increase the power signal. If the control error value is negative, it indicates that the actual operating point is above the target operating point, and the wireless power transmitter 100 can be requested to decrease the power signal.

[0335] -RP8: The RP8 data packet can report the received power level. Here, the RP8 data packet may be included only in the baseline protocol.

[0336] -CHS: CHS data packets can provide the battery charge level under load.

[0337] Figure 15 schematically shows the data flow for power transmission phase 840 in the extended protocol.

[0338] According to Figure 15, the wireless power receiver 200 can transmit CE to the wireless power transmitter 100 (S1510). Here, the wireless power receiver 200 can generally transmit CE data packets several times per second.

[0339] The wireless power receiver 200 can generally send RP (received power) data packets (RP in the extended protocol) to the wireless power transmitter 100 once every 1.5 seconds (S1515).

[0340] During the power transmission phase, control error packets (CEs) and received power packets (RPs) are data packets that should be repeatedly transmitted / received in accordance with the required timing constraints for controlling radio power.

[0341] The wireless power transmitter 100 can control the level of wireless power to transmit based on control error packets (CE) and received power packets (RP) received from the wireless power receiver 200.

[0342] On the other hand, in the extended protocol, the wireless power transmitter 100 can respond to the received power packet (RP) with bit patterns such as ACK, NAK, and ATN (S1520).

[0343] When the wireless power transmitter 100 responds with an ACK to a received power packet (RP / 0) with a mode value of 0, it means that power transmission can continue at the current level.

[0344] When the wireless power transmitter 100 responds with NAK to a received power packet (RP / 0) with a mode value of 0, it means that the wireless power receiver 200 should reduce its power consumption.

[0345] When the wireless power transmitter 100 responds with an ACK to a received power packet (RP / 1 or RP / 2) with a mode value of 1 or 2, it means that the wireless power receiver 200 has accepted the power correction value contained in the received power packet (RP / 1 or RP / 2).

[0346] When the wireless power transmitter 100 responds with NAK to a received power packet (RP / 1 or RP / 2) with a mode value of 1 or 2, it means that the wireless power receiver 200 did not accept the power correction value contained in the received power packet (RP / 1 or RP / 2).

[0347] A received power packet (RP / 1) with a mode value of 1, as described above, can represent a first calibration data point, and a received power packet (RP / 2) with a mode value of 2 can represent an additional calibration data point. Here, the wireless power receiver can transmit multiple received power packets (RP / 2) with a mode value of 2 to the wireless power transmitter to transmit multiple additional power calibration values, and the wireless power transmitter can perform the calibration process based on the received RP / 1 and multiple RP / 2s.

[0348] When the wireless power transmitter 100 responds to a received power packet (RP) with an Attention (ATN), it means that the wireless power transmitter 100 is requesting permission to communicate. In other words, the wireless power transmitter 100 can send an Attention (ATN) response pattern in response to an RP data packet to request permission to transmit the data packet. In other words, the wireless power transmitter 100 can send an Attention (ATN) to the wireless power receiver 200 in response to an RP data packet to request permission from the wireless power receiver 200 to transmit the data packet.

[0349] Selectively, the wireless power receiver 200 can transmit CHS (charge status) data packets to the wireless power transmitter 100 (S1525).

[0350] On the other hand, the wireless power transmitter 100 and the wireless power receiver 200 can exchange DSR (data stream response) data packets, CAP data packets, and NEGO data packets in order to initiate renegotiation of elements in the power transmission contract (generally, guaranteed load power).

[0351] For example, the wireless power receiver 200 can transmit a DSR data packet to the wireless power transmitter 100 (S1530), and the wireless power transmitter 100 can transmit a CAP to the wireless power receiver 200 (S1535).

[0352] Furthermore, the wireless power receiver 200 can transmit a NEGO data packet to the wireless power transmitter 100 (S1540), and the wireless power transmitter 100 can respond to the NEGO data packet by transmitting an ACK to the wireless power receiver 200 (S1545).

[0353] The data packets related to the start of the renegotiation phase can be summarized as follows:

[0354] -DSR: A DSR data packet may be set to one of the following values:

[0355] i) 0x00-DSR / nak: Indicates that the last received data packet from the wireless power transmitter 100 was rejected.

[0356] ii) 0x33-DSR / poll: Invite the wireless power transmitter 100 to send a data packet.

[0357] iii) 0x55-DSR / nd: Indicates that the last received data packet from the wireless power transmitter 100 was unexpected.

[0358] iv) 0xFF-DSR / ack: Confirms that the last received data packet from the wireless power transmitter 100 was processed correctly.

[0359] -CAP: The CAP data packet provides information about the functions of the wireless power transmitter 100. The specific details are as described above.

[0360] -NEGO:NEGO data packets can be requested from the wireless power transmitter 100 to be used in the renegotiation phase.

[0361] The wireless power transmitter 100 and the wireless power receiver 200 can utilize ADC (auxiliary data control), ADT (auxiliary data transport), and DSR data packets for the exchange of application-level data.

[0362] In other words, in terms of sending and receiving data transmission streams for the exchange of application-level data, the wireless power receiver 200 can transmit ADC / ADT to the wireless power transmitter 100 (S1550), and the wireless power transmitter 100 can transmit ACK / NAK to the wireless power receiver 200 in response (S1555). Also, the wireless power receiver 200 can transmit DSR to the wireless power transmitter 100 (S1560), and the wireless power transmitter can transmit ADC / ADT to the wireless power receiver (S1565).

[0363] Here, the data transmission stream plays the role of transmitting application-level data from the data stream initiator to the data stream responder. This application-level data can be broadly categorized into i) authentication applications and ii) exclusive (general-purpose) applications.

[0364] Among application-level data, messages / information related to the authentication application can be organized as follows:

[0365] A message used in an authentication procedure is called an authentication message. Authentication messages are used to carry information related to authentication. There are two types of authentication messages: one is an authentication request, and the other is an authentication response. Authentication requests are sent by authentication initiators, and authentication responses are sent by authentication responders. Wireless power transmitters and receivers can be either authentication initiators or authentication responders. For example, if a wireless power transmitter is an authentication initiator, a wireless power receiver becomes an authentication responder, and if a wireless power receiver is an authentication initiator, a wireless power transmitter becomes an authentication responder.

[0366] Authentication request messages include GET_DIGESTS, GET_CERTIFICATE, and CHALLENGE.

[0367] -GET_DIGESTS: This request can be used to retrieve certificate chain digests. The wireless power receiver 200 can request any number of digests at once.

[0368] -GET_CERTIFICATE: This request is used to read a segment of the target certificate chain.

[0369] -CHALLENGE: This request can be used to initiate the certification of product equipment for power transmission devices.

[0370] Authentication response messages include DIGESTS, CERTIFICATE, CHALLENGE_AUTH, and ERROR.

[0371] -DIGESTS: The wireless power transmitter 100 can send a certificate chain summary using a DIGESTS response and report slots containing valid certificate chain summaries.

[0372] -CERTIFICATE: This response can be used by the wireless power transmitter 100 to transmit the requested segment of the certificate chain.

[0373] -CHALLENGE_AUTH: The wireless power transmitter 100 can respond to a CHALLENGE request using CHALLENGE_AUTH.

[0374] -ERROR: This response can be used to transmit error information on the power transmitter.

[0375] Authentication messages can also be called authentication packets, authentication data, or authentication control information. Messages such as GET_DIGEST and DIGESTS can also be called GET_DIGEST packets or DIGEST packets.

[0376] On the other hand, as mentioned above, the wireless power receiver 200 and the wireless power transmitter 100 can transmit application-level data via a data transmission stream. The application-level data transmitted via the data transmission stream can consist of a data packet sequence with the following structure.

[0377] - Initial ADC data packet to open the stream.

[0378] i) The type of message contained in the stream.

[0379] ii) The number of data bytes in the stream.

[0380] - A series of ADT data packets, including the actual message.

[0381] - The final ADC / end data packet that closes the stream.

[0382] The following diagrams illustrate the data transmission streams for examples where the above-described ADC, ADT, and ADC / end data packets are used.

[0383] Figure 16 shows an example of an application-level data stream between a wireless power transmitter 100 and a wireless power receiver 200.

[0384] Referring to Figure 16, the data stream may include auxiliary data control (ADC) data packets and / or auxiliary data transport (ADT) data packets.

[0385] An ADC data packet is used to start (open) a data stream. An ADC data packet can indicate the type of message to be included in the stream and the number of data bytes. Conversely, an ADT data packet is a sequence of data containing the actual message. An ADC / end data packet is used to signal the end of a stream. For example, the maximum number of data bytes in a data transmission stream may be limited to 2047.

[0386] An ACK or NAC (NACK) is used to indicate whether the ADC data packet and ADT data packet have been received successfully. Control information necessary for wireless charging, such as a control error packet (CE) or DSR, may be transmitted between the transmission timings of the ADC data packet and the ADT data packet.

[0387] Such a data stream structure may be used to transmit and receive authentication-related information or other application-level information between the wireless power transmitter and receiver.

[0388] An example illustrating the operation between the wireless power transmitter 100 and the wireless power receiver 200 during the power transmission phase 840, as described above, is as follows:

[0389] Figure 17 shows a power control method according to one embodiment.

[0390] In Figure 17, during the power transmission phase, the wireless power transmitter 100 and the wireless power receiver 200 can control the amount of power transmitted by communicating in parallel with power transmission and reception. The wireless power transmitter and wireless power receiver operate at specific control points. The control points indicate the combination of voltage and current provided at the output terminal of the wireless power receiver when power transmission is performed.

[0391] More specifically, the wireless power receiver selects a desired control point—such as the desired output current / voltage and the temperature at a specific location on the mobile device—and additionally determines the actual control point currently in operation. Using the desired and actual control points, the wireless power receiver can calculate a control error value and transmit it to the wireless power transmitter as a control error packet.

[0392] The wireless power transmitter can then use the received control error packets to set / control new operating points—amplitude, frequency, and duty cycle—and control power transfer. Thus, control error packets are transmitted / received at regular time intervals during the power transfer phase. For example, the wireless power receiver can set the control error value to a negative number when attempting to reduce the current of the wireless power transmitter, and to a positive number when attempting to increase the current. In this way, in inductive mode, power transfer can be controlled by the wireless power receiver transmitting control error packets to the wireless power transmitter.

[0393] In resonant mode, operation may differ from that in inductive mode. In resonant mode, one radio power transmitter needs to serve multiple radio power receivers simultaneously. However, when controlling power transfer as in the inductive mode described above, the power transferred is controlled by communication with one radio power receiver, making it difficult to control power transfer to additional radio power receivers. Therefore, in the resonant mode described herein, the radio power transmitter transmits a common base power, and the radio power receiver controls the amount of power received by controlling its own resonant frequency. However, even in such operation of resonant mode, the method described in Figure 17 is not completely excluded, and control of additional transmitted power may be performed using the method in Figure 17.

[0394] <Profile-related operations>

[0395] Wireless charging methods include magnetic induction, which uses the magnetic induction phenomenon between a primary and secondary coil, and magnetic resonance, which transmits power by using magnetic resonance in a frequency band of several MHz at tens of kHz. Wireless charging standards for magnetic resonance are led by the A4WP (Audio-Four-Wave Power Program), while standards for magnetic induction are led by the WPC (Wireless Power Consortium). The WPC is designed to transmit and receive various state information and commands related to wireless charging systems in-band.

[0396] The WPC standard defines a baseline power profile (BPP) and an extended power profile (EPP). The following sections will explain BPP and EPP separately.

[0397] A. BPP (Baseline Power Profile)

[0398] BPP (Broad Power Transfer Profile) is a power transfer profile between wireless power transmitters and receivers that support power transmission up to 5W. BPP supports unidirectional communication from the wireless power receiver to the wireless power transmitter. This communication method can support ASK (amplitude shift keying). BPP has three protocol phases: Ping, configuration, and power transfer.

[0399] B.EPP (extended power profile)

[0400] EPP (Electronic Power Transfer Profile) is a power transfer profile between wireless power transmitters and receivers that support power transmission up to 15W. EPP supports bidirectional communication between wireless power receivers and wireless power transmitters. Communication from the wireless power receiver to the wireless power transmitter can be done using ASK (amplitude shift keying), and communication from the wireless power transmitter to the wireless power receiver can be done using FSK (frequency shift keying). EPP has protocol phases: Ping, configuration, negotiation, and power transfer.

[0401] (a) Compatibility with EPP

[0402] EPP can support higher-level profiles than BPP.

[0403] For example, if a BPP radio power receiver is placed on an EPP radio power transmitter, the EPP radio power transmitter can operate as a BPP radio power transmitter.

[0404] For example, if an EPP radio power receiver is placed on a BPP radio power transmitter, the EPP radio power receiver can operate as a BPP radio power receiver.

[0405] In other words, EPP can maintain compatibility with BPP.

[0406] (b) EPP instruction method for EPP wireless power receiver

[0407] An EPP wireless power receiver can indicate that it is an EPP wireless power receiver by setting the "neg" bit in the configuration packet (ieCFG) to 1. A specific example of the configuration packet is as described above.

[0408] (c) EPP Wireless Power Transmitter EPP Instruction Method

[0409] When an EPP radio power transmitter receives a configuration packet from a radio power receiver with the "neg" bit set to 1, the EPP radio power transmitter can respond to this with an ACK FSK bit pattern.

[0410] For reference, as mentioned above, BPP wireless power transmitters do not support the FSK communication method, and therefore cannot transmit FSK bit patterns. In this case, an EPP wireless power receiver that has set the "neg" bit to 1 and sent a configuration packet to a BPP wireless power transmitter will not receive the aforementioned ACK response, thus identifying the other wireless power transmitter as a BPP wireless power transmitter.

[0411] Meanwhile, wireless power transfer systems are seeking to provide new power transfer profiles, and among the proposed power transfer profiles is the MPP (magnetic power profile). The MPP can support Apple's proprietary extensions based on Qiv 1.3.0.

[0412] C.MPP (Magnet Power Profile)

[0413] MPP (Multi-Power Propagation) is a power transfer profile between wireless power transmitters and receivers that support power transmission up to 15W. MPP supports bidirectional communication between the wireless power receiver and wireless power transmitter. Communication from the wireless power receiver to the wireless power transmitter can use ASK (amplitude shift keying), and communication from the wireless power transmitter to the wireless power receiver can use FSK (frequency shift keying). In this case, a fast FSK (NCYCLE=128) can be used during the negotiation and power transfer phases.

[0414] MPP has protocol phases: Ping, configuration, MPP negotiation, and MPP power transfer.

[0415] (a) Compatibility with MPP

[0416] MPP can support higher-level profiles than BPP.

[0417] For example, if a BPP radio power receiver is placed on top of an MPP radio power transmitter, the MPP radio power transmitter can operate as a BPP radio power transmitter.

[0418] For example, if an MPP radio power receiver is placed on a BPP radio power transmitter, the MPP radio power receiver can operate as a BPP radio power receiver.

[0419] In other words, MPP can maintain compatibility with BPP.

[0420] (b) MPP operation of MPP wireless power receiver (MPP instruction method)

[0421] MPP wireless power receivers can use specific MPP indicators within extended ID packets.

[0422] For an MPP radio power receiver to indicate MPP support via XID, it must inform the radio power transmitter that an XID will be transmitted via an ID packet. The ID packets that the MPP radio power receiver will transmit may be as follows:

[0423] Figure 18 schematically shows the structure of an MPP ID packet.

[0424] According to Figure 18, in the MPP ID packet, the values ​​of the major version fields from b4 to b7 of B0 can be set to 1.

[0425] In an MPP ID packet, the values ​​of the minor version fields b0-b3 of B0 may be values ​​determined later.

[0426] In the MPP ID packet, the values ​​of the B1 and B2 manufacturing codes can be assigned to the PRMC code.

[0427] In an MPP ID packet, the value of the "ext" field in B3's b7 can be set to 1, instructing the system to send an additional XID packet.

[0428] In the MPP ID packet, the values ​​of the random identifier fields b0 to b6 in B3, and b3 to b7 in B4 and B5 can be set according to the random device identification policy.

[0429] Figure 19 schematically shows an example of an XID packet in MPP.

[0430] According to Figure 19, an XID packet in MPP can include fields such as "XID Selector," "Restricted," and "Freq Mask."

[0431] Here, whether or not MPP is supported can be determined by whether or not the value of "XID Selector" is 0xFE. In other words, if the value of XID B_0 is 0xFE, then XID can correspond to information indicating that the wireless power receiver supports MPP.

[0432] The "Restricted" field can correspond to information indicating whether the wireless power receiver operates in MPP restricted mode or MPP full mode. If the wireless power receiver chooses to operate in MPP restricted mode, the field can be set to 1. In other cases (for example, if the wireless power receiver chooses not to operate in MPP restricted mode), the field can be set to 0.

[0433] The "Preferred Frequency" field can represent the MPP preferred frequency. Here, the radio-power receiver can set this field to 128 kHz if it intends to retrieve information from the radio-power transmitter before frequency switching (during the negotiation phase). Otherwise, the radio-power receiver can set this field to 360 kHz.

[0434] The "Freq Mask" field can correspond to a field used to determine whether or not a 360kHz operating frequency is supported. In other words, if the "FreqMask" field is set to 0, 360kHz is supported.

[0435] In summary, the wireless power transmitter can determine whether the wireless power receiver supports MPP by checking whether the "ext" bit of the ID received from the wireless power receiver is set to 1, and whether the B_0 of the XID is set to 0xFE.

[0436] (c) MPP operation of MPP wireless power transmitter (MPP instruction method)

[0437] After sensing the placement of a wireless power receiver on the charging surface, the MPP wireless power transmitter can identify the receiver by performing a digital ping using the information contained in the ID and XID packets.

[0438] Here, the wireless power transmitter can determine that the wireless power receiver supports MPP if all of the following conditions are met:

[0439] -Qi version: The Qi protocol version of the ID packet is set to (Major=1, Minor=TBD) or higher.

[0440] -MPP support announcement: The lower header (byte 0) of the XID packet is set as the MPP selector.

[0441] If the two conditions mentioned above are not met, the wireless power transmitter may proceed with the subsequent steps according to the Qiv1.3 specification.

[0442] On the other hand, in response to the MPP operating mode requested by the MPP radio power receiver in the XID packet, the radio power transmitter performs the following:

[0443] - Restricted profile activation (MPP restricted mode): When the "restricted" flag is set to 1.

[0444] -Full profile activation (MPP full mode): If the "restricted" flag is set to 0.

[0445] Specific examples of the restricted profiles and the full profiles will be discussed later.

[0446] On the other hand, if an MPP radio-power transmitter receives a configuration packet from a radio-power receiver with the "neg" bit set to 1, the MPP radio-power transmitter can respond to this (in MPP full mode) with an MPP ACK FSK bit pattern.

[0447] For reference, MPP-restricted wireless power transmitters do not support the FSK communication method, and therefore cannot transmit FSK bit patterns. However, since MPP-restricted wireless power transmitters use a 360kHz operating signal for power transmission, an MPP wireless power receiver that sends a configuration packet with the "neg" bit set to 1 to a wireless power transmitter operating in MPP-restricted mode can identify the other wireless power transmitter as an MPP-restricted wireless power transmitter via the operating frequency.

[0448] (d) MPP mode

[0449] On the other hand, MPP has two modes. One is MPP Restricted mode (or MPP Baseline Profile), and the other is MPP Full mode (or MPP Full Profile).

[0450] To briefly explain the difference between the two, in MPP restricted mode, the "restricted" field in the XID is set to 1, while in MPP full mode, the "restricted" field in the XID is set to 0.

[0451] Furthermore, FSK communication is not supported in MPP restricted mode, but it is supported in MPP full mode.

[0452] Furthermore, since FSK communication is not supported in MPP-restricted mode, it is not possible to send an MPP ACK to the CFG, and therefore MPP negotiation is not supported in MPP-restricted mode. In contrast, since FSK communication is supported in MPP-full mode, it is possible to send an MPP ACK to the CFG, and therefore MPP negotiation is supported in MPP-full mode.

[0453] The following provides a more detailed explanation of MPP limited mode and MPP full mode. Note that MPP limited mode can be used in conjunction with the MPP baseline profile, and MPP full mode can be used in conjunction with the MPP full profile.

[0454] Below, we will provide a more detailed explanation of the protocols in each mode to help you gain a better understanding of MPP restricted mode and MPP full mode.

[0455] i) MPP Restricted mode

[0456] As mentioned above, FSK communication is not supported in MPP restricted mode. This means that in MPP restricted mode, there may be no data packets transmitted from the wireless power transmitter to the wireless power receiver. Against this backdrop, the protocol in MPP restricted mode will be explained using diagrams.

[0457] Figure 20 schematically shows the protocol in MPP restriction mode.

[0458] According to Figure 20, the radio power receiver can transmit a SIG to the radio power transmitter on a first operating frequency (e.g., 128 kHz). This first operating frequency can correspond to an operating frequency capable of performing BPP and / or EPP. Furthermore, this first operating frequency can correspond to the frequency at which the radio power transmitter operates.

[0459] A wireless power receiver can transmit an ID packet to a wireless power transmitter on a first operating frequency. In this case, since an XID is always transmitted in MPP, the "ext" bit of the ID can be set to 1 to indicate that an XID should be transmitted further.

[0460] The wireless power receiver can transmit XID packets to the wireless power transmitter on a first operating frequency.

[0461] In this case, the value of B0 in XID is 0xFE, and setting the value of B0 in XID to 0xFE can correspond to information indicating that the radio power receiver supports MPP. In addition, the "restricted" field in XID at this time can be set to 1 to indicate that the radio power receiver is operating in MPP restricted mode.

[0462] If the wireless power transmitter receives the aforementioned XID packet indicating MPP restriction mode, the wireless power transmitter can remove the power signal and restart the Ping phase at the new operating frequency.

[0463] Once the ping phase is restarted, the radio power receiver will begin again with SIG transmission, although the operating frequency at this time may be the second operating frequency (e.g., 360 kHz).

[0464] Subsequently, the radio power receiver transmits ID, XID, and CFG packets to the radio power transmitter at the second operating frequency. In addition, the radio power receiver transmits a CEP to the radio power transmitter, enabling it to receive radio power based on the MPP baseline from the radio power transmitter.

[0465] ii) MPP Full mode

[0466] As mentioned above, FSK communication is supported in MPP full mode. That is, in MPP full mode, there are data packets transmitted from the radio power transmitter to the radio power receiver. In other words, MPP negotiations can take place between the radio power transmitter and the radio power receiver. Against this backdrop, the MPP full mode protocol will be explained using diagrams.

[0467] Figures 21 and 22 schematically illustrate the protocol in MPP full mode.

[0468] First, as shown in Figure 21, the radio power receiver can transmit a SIG to the radio power transmitter on a first operating frequency (e.g., 128 kHz). In this case, the first operating frequency can correspond to an operating frequency on which BPP and / or EPP can be performed. Furthermore, the first operating frequency in this case can correspond to the frequency on which the radio power transmitter is driven.

[0469] A wireless power receiver can transmit an ID packet to a wireless power transmitter on a first operating frequency. In this case, since an XID is always transmitted in MPP, the "ext" bit of the ID can be set to 1 to indicate that an XID should be transmitted further.

[0470] The wireless power receiver can transmit XID packets to the wireless power transmitter on a first operating frequency.

[0471] In this case, the value of B0 in XID is 0xFE, and setting the value of B0 in XID to 0xFE can correspond to information indicating that the radio power receiver supports MPP. In addition, the "restricted" field in XID at this time can be set to 0 to indicate that the radio power receiver is operating in MPP full mode.

[0472] On the other hand, in MPP full mode, unlike MPP limited mode, the radio power transmitter does not remove the power signal even if it receives an XID packet from the radio power receiver. In this case, the radio power receiver still transmits CFG packets to the radio power transmitter after the XID packet because the power signal was not removed.

[0473] The wireless power receiver can then receive an MPP ACK from the wireless power transmitter as a response to the aforementioned CFG packet.

[0474] Upon receiving an MPP ACK, the radio power receiver enters the negotiation phase with the radio power transmitter, and both the radio power receiver and the radio power transmitter can proceed with the negotiation.

[0475] After negotiations are complete, the wireless power receiver can enter the power transfer phase with the wireless power transmitter.

[0476] Meanwhile, the radio power receiver transmits an EPT packet to the radio power transmitter. Upon receiving the EPT packet, the radio power transmitter removes the power signal and can subsequently restart the Ping phase at the new operating frequency.

[0477] As shown in Figure 22, once the Ping phase is restarted, the radio power receiver will begin again with SIG transmission. However, the operating frequency at this time may be the second operating frequency (e.g., 360 kHz).

[0478] Subsequently, the radio power receiver transmits ID, XID, and CFG packets to the radio power transmitter at the second operating frequency. The radio power receiver can then receive an MPP ACK from the radio power transmitter.

[0479] Upon receiving the MPP ACK, the radio power receiver enters a negotiation phase with the radio power transmitter at a second operating frequency, and both the radio power receiver and the radio power transmitter can proceed with the negotiation.

[0480] After negotiations are complete, the radio power receiver enters the power transfer phase with the radio power transmitter at the second operating frequency. Simultaneously, the radio power receiver can receive radio power from the radio power transmitter based on MPP full mode by sending an XCE to the radio power transmitter and receiving a response (e.g., an ACK).

[0481] The following provides a more detailed explanation of this specification.

[0482] An example of differential biphase encoding is described below.

[0483] Figure 23 schematically shows an example of differential bi-phase encoding.

[0484] As shown in Figure 23, a wireless power transmitter can arrange each data bit based on 512 cycles of the power signal frequency (NCYCLE=512).

[0485] For example, a wireless power transmitter can use two transitions to represent 1 (One). Additionally, a wireless power transmitter can use one transition to represent 0.

[0486] In other words, a wireless power transmitter can, for example, indicate 1 based on two transitions of 256 cycle units, and a wireless power transmitter can, for example, indicate 0 based on one transition of 512 cycle units.

[0487] In summary, the WPC wireless charging standard has two communication methods: FSK and ASK. FSK can be used for communication transmitted from PTx to PRx.

[0488] As shown in the diagram, FSK can recognize 512 cycles with one bit. If there is one transition within one bit, which represents 512 cycles, it is recognized as bit 0. If a transition occurs every 256 cycles within one bit, resulting in a total of two transitions, it is recognized as bit 1.

[0489] Figure 24 schematically shows an example of an asynchronous serial format.

[0490] As shown in Figure 24, a wireless power transmitter can use an 11-bit asynchronous serial format to transmit one data byte. This format can consist of a start bit, eight data bits for the byte, a parity bit, and a single stop bit. Here, the start bit can be ZERO, and the stop bit can be ONE.

[0491] In other words, Figure 24 describes the bit recognition method for FSK communication. A byte in the wireless charging standard can be composed of a total of 11 bits. Here, the first bit can be the START BIT (the START BIT is always fixed at 0). The next 8 bits represent the data. After that, there are the parity bit and the STOP BIT. Here, the STOP BIT is always fixed at 1.

[0492] Figure 25 schematically shows an example of the structure of a data packet.

[0493] As shown in Figure 25, a wireless power transmitter can communicate with a wireless power receiver using data packets. A data packet can consist of a series of bytes that the wireless power transmitter needs to send in a continuous sequence; that is, there may be no pause between two consecutive bytes. As shown in Figure 25, a data packet can consist of three parts: a header, a message, and a checksum. Here, the header, message, and checksum can consist of a sequence of three or more encoded bytes.

[0494] A wireless power receiver can consider a data packet to have been successfully received in the following cases:

[0495] - When the wireless power receiver cannot detect a parity error in the bytes that make up the data packet. This includes the header byte, message byte, and checksum byte.

[0496] -When the wireless power receiver detects a stop bit in the checksum byte.

[0497] - If the wireless power receiver determines that the checksum byte matches.

[0498] If a wireless power receiver fails to successfully receive a data packet, it may discard the data packet and not use the information contained within it.

[0499] On the other hand, the header can be explained with a diagram as follows.

[0500] Figure 26 schematically shows examples of header types and their corresponding message sizes.

[0501] As shown in Figure 26, the header can consist of a single byte indicating the data packet type. The header can also implicitly provide the size of the message contained within the data packet. Here, the number of bytes in the message can be calculated based on the value contained in the data packet header. In other words, the header can represent the size of the message (payload).

[0502] Here's how to calculate the message size:

[0503] As shown in Figure 26, the number of header values ​​that can be represented as a single byte is 2^8. That is, a header with a size of one byte can, for example, indicate values ​​from 0 to 255.

[0504] Here, for example, the maximum value that can be represented as a header with a size of one byte corresponds to the case where the header has the value 0xFF. And when the value indicated by this header is expressed in decimal, it corresponds to 255.

[0505] If the header indicates the maximum value it can represent, which is 255, then the size of the message that can be derived based on the value indicated by the header can be determined by 20 + (header(=255) - 224) / 4. Here, calculating 20 + (255 - 224) / 4 gives the value 27.75. Considering that the final size of the message is determined by the integer value obtained by truncating the value obtained from the above formula, the size of the message can be determined to be 27 bytes based on the header value indicating the maximum value it can represent, which is 255.

[0506] On the other hand, with respect to messages, the wireless power transmitter must ensure that the message contained in the data packet matches the data packet type indicated in the header. Furthermore, the first byte of the message, byte B0, can be located immediately after the header.

[0507] Finally, regarding checksums, a checksum can consist of a single byte that allows a radio power receiver to check for transmission errors. Here, the radio power transmitter can calculate the checksum as follows:

[0508] [Formula 1]

number

[0509] Here, C is the calculated checksum, H is the header byte, and B0, B1, ..., Blast are the message bytes.

[0510] If the calculated checksum C and the checksum byte included in the data packet are not the same, the wireless power receiver can determine that the checksums do not match.

[0511] In summary, the data packet structure via FSK communication for wireless charging is as shown in the diagram above. As explained above, the data packet can consist of a header, a message, and a checksum. The header and checksum can each consist of 1 byte. The header includes a method for representing the message size from 0x00-0x1F / 0x20-0x7F / 0x80-0xDF / 0xE0-0xFF. Therefore, as explained above, the header can represent size values ​​from 1 to 27.

[0512] On the other hand, both the wireless power transmitter and the wireless power receiver can transmit a data transmission stream to the other party during the power transfer phase. Here, the data transmission stream may include, for example, ADC packets and / or ADT packets. The ADT packets will be described in more detail below.

[0513] Figure 27 shows a schematic example of an ADT packet.

[0514] According to Figure 27, ADT data packets transmit application data from the data transmission stream via a power receiver or power transmitter. Here, ADT data packet sizes from 1 to 7 can be used. Of course, the size of the ADT data packet can be larger than those listed above.

[0515] In this case, ADT data packets of each size can be used with odd and even headers. For example, assuming the size of an ADT data packet is 7 bytes, there will be 7-byte ADT data packets with odd headers and 7-byte ADT data packets with even headers.

[0516] As an example, a more specific explanation of ADT packets for wireless power transmitters is as follows:

[0517] <ADT packet from wireless power transmitter>

[0518] Here, the ADT packet can contain a data field, which is as follows:

[0519] -Data fields: These can be appropriately defined by the application layer.

[0520] The following DSR data packets are as follows: In other words, the following packets exist as responses to the ADT data packets from the wireless power transmitter.

[0521] -DSR / ack: The wireless power receiver has successfully processed the packet data.

[0522] -DSR / nak: The radio power receiver received the last power transmitter data packet but was unable to process the packet's data. For example, the radio power receiver may use this response if it is currently processing the data or unable to buffer it.

[0523] -DSR / nd: The wireless power receiver does not have an incoming data transport stream open.

[0524] -DSR / poll: The wireless power receiver did not receive the last power transmitter data packet.

[0525] In other words, DSR / poll is a packet that a radio power receiver sends to a radio power transmitter. DSR / poll can mean that the radio power transmitter is authorized to send a packet (either following a packet that was already being sent, or a packet that it intends to send). That is, as explained above, DSR / poll can invite the radio power transmitter to send a data packet.

[0526] <ADT packet from a wireless power receiver>

[0527] Here, the ADT packet can contain a data field, which is as follows:

[0528] -Data fields: These can be appropriately defined by the application layer.

[0529] The following are some of the responses that a wireless power receiver can give to an ADT data packet.

[0530] -ACK: The wireless power transmitter has successfully processed the packet data.

[0531] -NAK: The wireless power transmitter is unable to process the packet data.

[0532] -ND: The wireless power transmitter does not have an incoming data transport stream open.

[0533] -ATN: The wireless power transmitter requests permission for communication.

[0534] In summary, TPL (Transport Layer) can be defined as the algorithm for transmitting data in wireless charging. Here, the data stream can be opened / closed via ADC packets. When the data stream is open, the wireless power transmitter and / or wireless power receiver can transmit the actual data to the other party by sending an ADT packet. The ADT can consist of data. The ADT can be divided into Even / Odd by a header. Currently, the size of an ADT packet can consist of 1 to 7 bytes.

[0535] On the other hand, as explained above, the WPC Qi wireless charging standard provides an authentication function.

[0536] Certification is a procedure to verify whether a device has actually obtained Qi certification, a standard set by a standards organization, and is a method for confirming the existence of a standard product. For certification, the wireless power transmitter and wireless power receiver can exchange certification-related data with each other via IB (Inband) communication. The wireless power transmitter and wireless power receiver can send and receive data with each other via the transport layer.

[0537] In this case, the wireless power transmitter can send a certificate to the wireless power receiver, and in the process of sending the certificate, the wireless power transmitter can transmit a large amount of data to the wireless power receiver. The wireless power transmitter can then use an FSK to transmit a data stream to the wireless power receiver.

[0538] The use of FSK here means that there may be a difference in communication speed between the wireless power transmitter and the wireless power receiver, and between the wireless power receiver and the wireless power transmitter. Therefore, FSK, which can be used for communication from the wireless power transmitter to the wireless power receiver, is relatively slower than ASK, which can be used for communication from the wireless power receiver to the wireless power transmitter.

[0539] Furthermore, Fast FSK is provided at the physical layer to improve bidirectional communication speeds.

[0540] However, fast FSK on the physical layer alone, as described above, cannot implement a substantial speed increase.

[0541] Therefore, while it is possible to increase the communication speed at the physical layer via Fast FSK, there is a limit to how much the actual communication speed can increase if the data transmission algorithm at the transport layer is not changed. In other words, the in-band speed of communication and the data communication speed may differ from each other.

[0542] In other words, it is as follows:

[0543] The speed of FSK at the physical layer can be improved through a fast FSK method that adjusts the number of Ncycles (the number of cycles required to represent one bit) (i.e., while 1 bit is defined as 512 cycles, subsequent bits can be defined as 256, 128, 64, etc.). However, currently, depending on the specifications, the size of the ADT packet is fixed at 7 bytes. Accordingly, even if the actual FSK communication speed at the physical layer improves, the data communication speed from the TPL side does not improve. Therefore, the actual data communication speed may not improve.

[0544] This specification provides a configuration for increasing the ADT size by applying Fast FSK. Furthermore, it provides, through various experimental results, how much the ADT size can be increased.

[0545] The following drawings have been prepared to illustrate a specific example of this specification. The names of specific devices and signals / messages / fields shown in the drawings are presented as examples only, and the technical features of this specification are not limited to the specific names used in the following drawings.

[0546] Figure 28 is a sequence diagram of a method for transmitting wireless power according to one embodiment of this specification.

[0547] According to Figure 28, the wireless power transmitter can enter the power transfer phase, which is related to transmitting wireless power (S2810).

[0548] As described above, the power transfer phase 840 is part of the protocol in which the actual power is transmitted to the load of the wireless power receiver 200. Here, the power transfer can proceed according to the terms of the power transfer contract generated in the negotiation phase 830.

[0549] The wireless power transmitter 100 and the wireless power receiver 200 can exchange application level data from the data transmission stream throughout the power transfer phase 840.

[0550] Here, the content of the data transport stream transmitted by the wireless power transmitter to the wireless power receiver via the ADC, ADT, etc., is as described above. And the content of the data transport stream transmitted by the wireless power receiver to the wireless power transmitter via the ADC, ADT, etc., is also as described above.

[0551] Specific examples of the power transfer phase are as described above. Repeated content will be omitted.

[0552] The wireless power transmitter may transmit ADT (auxiliary data transport) packets to the wireless power receiver during the power transfer phase (S2820). The wireless power transmitter may transmit the ADT packets to the wireless power receiver based on FSK (Frequency Shift Keying). Here, the maximum size of the ADT packets can be determined based on the number of cycles used in the FSK.

[0553] According to this specification, a wireless power transmitter (and / or wireless power receiver) can transmit ADT packets to a counterpart using FSK. That is, while a wireless power receiver can normally transmit ADT packets to a counterpart based on ASK, this specification also provides examples in which a wireless power receiver transmits ADT packets to a counterpart using FSK as well as ASK. In this case, if the sender of the ADT packet is a wireless power transmitter, the counterpart may be a wireless power receiver, and if the sender of the ADT packet is a wireless power receiver, the counterpart may be a wireless power transmitter.

[0554] Here, the wireless power transmitter can perform FSK communication by varying the number of cycles that make up one bit. Specifically, the wireless power transmitter can perform FSK communication based on one of the following cycle counts: 512, 256, 128, or 64.

[0555] At this time, the number of cycles is set for the wireless power transmitter from the wireless power receiver. More specifically, the wireless power transmitter can receive an SRQ (specific request) packet from the wireless power receiver. At this time, the SRQ packet may contain information regarding the number of cycles. Here, the wireless power transmitter can receive the SRQ packet during the negotiation phase or the renegotiation phase.

[0556] As explained above, if the FSK signal, which was previously represented at 512 cycles per bit, can be represented at 256 / 128 / 64 cycles per bit, Fast FSK can be achieved. Below, we will discuss the data rate improvement in the TPL related to the speed improvement at the physical layer for Fast FSK.

[0557] First, let's discuss the expansion of ADT packet size.

[0558] 1. Expanding the ADT packet size

[0559] Figure 29 shows an example of the sizes of ADT packets up to 7 bytes.

[0560] According to Figure 29, the ADT header and its corresponding bytes are as follows:

[0561] -0x16 / 0x17: ADT / 1e, ADT / 1o (1 byte of ADT even / odd)

[0562] -0x26 / 0x27:ADT / 2e,ADT / 2o(2 bytes ADT even / odd)

[0563] -0x36 / 0x37:ADT / 3e,ADT / 3o(3 bytes ADT even / odd)

[0564] -0x46 / 0x47:ADT / 4e,ADT / 4o(4 bytes ADT even / odd)

[0565] -0x56 / 0x57:ADT / 5e,ADT / 5o(5 bytes ADT even / odd)

[0566] -0x66 / 0x67:ADT / 6e,ADT / 6o(6 bytes ADT even / odd)

[0567] -0x76 / 0x77:ADT / 7e,ADT / 7o(7 bytes ADT even / odd)

[0568] On the other hand, as described above, a fast FSK is provided. Therefore, this specification provides a configuration in which the ADT size is increased so that a wireless power transmitter (or wireless power receiver) transmits even more data to a wireless power receiver (or wireless power transmitter) at the same time.

[0569] In this case, the size of the ADT packet may not be fixed to an arbitrary number.

[0570] Therefore, as explained above, ADT packets are data packets. Consequently, the size of an ADT packet is not determined by an arbitrary number. As explained in Figure 26 above, the size of an ADT packet, which is a data packet, is determined based on the header value.

[0571] Furthermore, the number of units in the header value of an ADT packet can be fixed at either 6 or 7. For example, if the first number of units in the header value of an ADT packet is 6, it may be an "even" header, and if the first number of units in the header value of an ADT packet is 7, it may be an "odd" header.

[0572] Applying these principles, the sizes of ADT packets larger than 7 bytes are summarized as follows:

[0573] Figure 30 shows an example of the sizes of ADT packets larger than 7 bytes.

[0574] As shown in Figure 30, as explained above, the header value can be either 0x-6 or 0x-7. If the header ends in 6, it may be an "Even ADT" header, and if the header ends in 7, it may be an "Odd ADT" header.

[0575] Here, the size of the extended ADT packet is determined by the existing header and message size rules. The extended ADT packet can be applied to both PRx and PTx together.

[0576] The ADT header and bytes at that time are as follows:

[0577] -0x86 / 0x87: ADT / 8e, ADT / 8o (8-byte ADT even / odd)

[0578] -0x96 / 0x97: ADT / 10e, ADT / 10o (10-byte ADT even / odd)

[0579] -0xA6 / 0xA7:ADT / 12e,ADT / 12o (ADT even / odd of 12 bytes)

[0580] -0xB6 / 0xB7:ADT / 14e,ADT / 14o (ADT even / odd of 14 bytes)

[0581] -0xC6 / 0xC7:ADT / 16e,ADT / 16o(16 bytes ADT even / odd)

[0582] -0xD6 / 0xD7:ADT / 18e,ADT / 18o (ADT even / odd of 18 bytes)

[0583] -0xE6 / 0xE7:ADT / 21e,ADT / 21o(21 bytes ADT even / odd)

[0584] -0xF6 / 0xF7:ADT / 25e,ADT / 25o(25 bytes ADT even / odd)

[0585] In summary, extended ADT packets are not arbitrary in size, but can have data sizes of 8, 10, 12, 14, 16, 18, 21, or 25 bytes. Of course, packets with other data sizes will also be provided (for example, if a different rule can be established to determine the size of ADT packets).

[0586] 2. Expansion limit on ADT packet size

[0587] The following explains the limits to which the ADT size related to Fast FSK can be expanded.

[0588] As explained above, Fast FSK is a method that reduces the number of cycles required to represent one bit in an existing FSK signal, which previously represented one bit in 512 cycles, to 256 / 128 / 64 cycles.

[0589] This specification provides an example of limiting the ADT size in the TPL layer algorithm when reducing the FSK signal to 256 / 128 / 64 cycles according to a time constraint.

[0590] First, in order to calculate the limit of the ADT size per cycle, it is necessary to calculate the time required to send an ADT packet.

[0591] Assuming that 512 cycles are required to represent one bit, the transmission times for each ADT packet are summarized in the table below.

[0592] [Table 2]

[0593] The method for calculating the transmission time, as described above, can be explained in more detail as follows.

[0594] For the sake of explanation, we will use the case where the ADT packet size is 7 bytes as a representative example.

[0595] - Based on ADT 7 bytes, it consists of Header (1 byte) + Message (ADT / 7e, 7 bytes) + checksum (1 byte) (total 9 bytes)

[0596] - Wireless charging operates within the 110kHz-148kHz range. Calculations are based on the slowest (110kHz) and fastest (148kHz) frequency ranges (for message transmission speeds).

[0597] Example) 512 cycles * 11 bits * 9 bytes = 50688 cycles (ADT / 7 standard) -> 50688 cycles / 110 kHz = 460.8 ms (Preamble excluded)

[0598] The calculation method described above can also be applied to ADT packets of other sizes.

[0599] For example, the packet duration can be expressed mathematically as follows:

[0600] [Formula 2] data_bits=11*(data_bytes+2) packet_time=(NCYCLE / FOP)*data_bits=(NCYCLE / FOP)*{11*(data_bytes+2)} ADT_Bytes=floor{(520ms*FOP) / (11*NCYCLE)-2}

[0601] Here, NCYCLE can mean the number of cycles. FOP can mean the operating frequency. "data_bits" can mean the number of bits in the corresponding byte. "Data_bytes" can indicate the size of the byte.

[0602] [Table 3]

[0603] On the other hand, taking into account the packet time mentioned above, the required time for cycles and ADT packet sizes at a drive frequency of 110 kHz is summarized in the table below.

[0604] [Table 4]

[0605] In the table above, the parts in bold correspond to cases where the time taken is the same as or shorter than the time taken for a 7-byte ADT size over 512 cycles.

[0606] Below, we will explain why we marked cases with a time shorter than 7 bytes based on a 7-byte ADT size.

[0607] During the power transfer phase in which ADT packets are transmitted, as described above, the wireless power transmitter receives CE packets from the wireless power receiver for power control. The CE packets that the wireless power receiver transmits to the wireless power transmitter have a time specification called the CE interval.

[0608] Figure 31 schematically shows an example of the CE (control error) interval.

[0609] According to Figure 31, the CE interval can correspond to a time constraint in the radio power receiver. The CE interval is represented by the symbol t_interval. In this case, when both the radio power transmitter and radio power receiver are Qi version 1.3 or higher and the extended protocol is applied, the maximum value of the CE interval can be 700ms. Otherwise, the maximum value of the CE interval can be 350ms.

[0610] In summary, if the Qi version for TPL is v1.3 or higher, the "Control error Interval" can be extended from the existing 350ms to 700ms.

[0611] Here, the ADT packet must be sent within the CE packet interval (e.g., 700ms). That is, the size of the ADT packet may depend on the CE packet interval.

[0612] In this case, if the number of cycles used in FSK is 512, as is currently the case, then the packets that can transmit data within the CE interval are ADT packets with a size of 7 bytes. In other words, ADT packets larger than ADT / 7e or ADT / 7o cannot be transmitted.

[0613] Specifically, while an actual ADT 7-byte message packet is only 460ms (excluding preamble), considering control time and / or cep packet time, it is impossible to send ADT packets larger than 7 bytes.

[0614] For example, as shown in Figures 34 and 35 below, if Margin 1 and Margin 2 are calculated to be 120ms + 50ms or more, the maximum size of the ADT that can be transmitted within 700ms can be 7 bytes.

[0615] For a clearer understanding of the specification, the time required for data communication between the wireless power transmitter and wireless power receiver and the size of the associated ADT are described below.

[0616] 1) Data communication from PRx to PTx

[0617] Figure 32 shows an example of data communication from a wireless power receiver to a wireless power transmitter.

[0618] According to Figure 32, the time can be calculated as follows.

[0619] Time calculation (@110khz standard) ≦700ms: CE packet(22ms)+Tdelay(5ms~)+ Tcontrol(24ms~)+ ADTpacket + Tresponse(3-10ms)+ ACK(38ms)+ Tsilent(6ms~)

[0620] Considering the aforementioned time calculations, theoretically, an ADT packet cannot exceed 7 or 8 bytes (based on FSK cycles of 512 cycles).

[0621] 2) Data communication from PTx to PRx

[0622] Figure 33 shows an example of data communication from a wireless power transmitter to a wireless power receiver.

[0623] According to FIG. 33, the time can be calculated as follows.

[0624] Time calculation (@110khz reference) ≤ 700ms: CE packet (22ms) + Tdelay (5ms~) + Tactive (21ms~) + DSR / ack (22ms) + Tresponse (3 - 10ms) + ADT packet + Tsilent (6ms~)

[0625] Considering the above time calculation, theoretically, the ADT packet cannot exceed 7 or 8 bytes. (Based on 512 cycles of FSK cycles)

[0626] The above-described time calculation corresponds to the calculation assuming the minimum value of the time requirement in the specification. Therefore, in an actual product, the actual margin for driving can be assumed. For this reason, it is difficult for a packet with an ADT size exceeding 7 bytes to be transmitted during the 700ms corresponding to the CEP interval. Therefore, under the assumption of 512 cycles, the ADT payload of 7 bytes can be considered as the maximum byte size during the 700ms corresponding to the CEP interval.

[0627] <When the CE interval is supported up to a maximum of 700ms>

[0628] Applying the examples described so far and assuming a driving frequency of 110khz, the maximum ADT size is summarized as shown in the following table.

[0629]

Table 5

[0630] In the table above, bolded entries represent cases where the time taken is the same as or shorter than the time taken for a 7-byte ADT size in 512 cycles. Underlined entries represent examples where the maximum byte size can be increased through implementation, even if the time taken is longer than the time taken for a 7-byte ADT size.

[0631] Based on the slowest drive frequency of 110kHz, and considering the CE interval (700ms when TPL is applied), it is possible to transmit up to 7 bytes (or 8 bytes) of ADT size based on 512 cycles.

[0632] -By reducing the FSK cycles to 256 cycles and modifying the physical layer of the Fast FSK, the ADT size can be limited to 16 bytes (or 21 bytes).

[0633] -By reducing the FSK cycles to 128 cycles / 64 cycles and applying the physical layer of Fast FSK, the ADT size can be expanded to the maximum of 25 bytes.

[0634] -Intermediate cycles between 512 cycles and 256 cycles will not send an ADT size exceeding 7 bytes based on the 512 cycles standard. (For example, in the case of 384 cycles, the ADT payload will not exceed 12 bytes.) (The maximum ADT payload can be expanded up to 18 bytes considering the margin.)

[0635] Assuming a drive frequency of 148 kHz, the maximum ADT size is summarized in the table below.

[0636] [Table 6]

[0637] In the said table, boldface corresponds to cases having a time equal to or shorter than the time for a 10-byte ADT size at 512 cycles. The underlined part corresponds to examples where, even if the time for a 10-byte ADT size is longer, the maximum bytes can be increased depending on the implementation.

[0638] Based on the examples described so far, if the simulation is actually implemented, it will be as described in the following drawings.

[0639] Figure 34 shows the result of simulating an example of ADT transmission using 512 Cycles-based FSK.

[0640] According to Figure 34, assuming FSK at 512 cycles, the CEP interval can be fixed at 600 ms. When Margin1 is assumed to be 120 ms and Margin2 is assumed to be 50 ms, a 7-byte ADT packet is transmitted.

[0641] Figure 35 shows the result of simulating an example of ADT transmission using 256 Cycles-based FSK.

[0642] According to Figure 35, assuming FSK at 256 cycles, the CEP interval can be fixed at 700 ms. When Margin 1 is assumed to be 120 ms and Margin 2 is assumed to be 50 ms, an ADT packet with a size larger than 21 bytes is not transmitted. If the Ncycles of FSK is reduced to 256 Cycles or less, it is also possible to transmit an ADT packet with a maximum Payload of 25 bytes or more within the CEP interval of 700 ms.

[0643] <When only values of the CE interval smaller than a maximum of 700 ms are supported>

[0644] When Fast FSK is applied, the CEP interval can be kept at the existing maximum / target intervals of 350ms and 250ms without increasing it to 700ms for fast power control.

[0645] Therefore, if the CEP interval increases to 700ms during TPL, the Power control interval increases, which may not be advantageous for power control. Furthermore, for faster power control, the CEP interval can be advanced to a target of 250ms and a maximum of 350ms. The following points can be applied in such cases.

[0646] 1) If you want to advance the CEP interval to 250ms,

[0647] When increasing the CEP interval to 250ms, it can be defined as follows, taking into account the communication time of the ADT size.

[0648] At an FSK communication speed of 512 cycles, it is possible to transmit 1 byte (or not transmit at all); at an FSK communication speed of 256 cycles, it is possible to transmit up to 3 bytes; at an FSK communication speed of 128 cycles, it is possible to transmit up to 8 bytes; and at an FSK communication speed of 64 cycles, it is possible to transmit up to 21 bytes of ADT packets.

[0649] [Table 7]

[0650] In the table above, bolded entries represent cases where the time taken is shorter than the time taken for a 1-byte ADT size in 512 cycles. Underlined entries represent examples where the maximum byte size can be increased through implementation, even if the time taken is the same as or longer than the time taken for a 1-byte ADT size.

[0651] 2) If the CEP interval is advanced to 350ms,

[0652] When increasing the CEP interval to 350ms, it can be defined as follows, taking into account the communication time of the ADT size.

[0653] At an FSK communication speed of 512 cycles, it is possible to transmit up to 2 bytes (or up to 3 bytes of ADT); at an FSK communication speed of 256 cycles, it is possible to transmit up to 7 bytes (or up to 8 bytes of ADT); at an FSK communication speed of 128 cycles, it is possible to transmit up to 16 bytes (or up to 18 bytes of ADT); and at an FSK communication speed of 64 cycles, it is possible to transmit up to 25 bytes of ADT packets.

[0654] [Table 8]

[0655] In the table above, bolded entries represent cases where the time taken is shorter than that for a 3-byte ADT size over 512 cycles. Underlined entries represent examples where the maximum byte size can be increased through implementation, even if the time taken is the same as or longer than that for a 1-byte ADT size.

[0656] The examples described in this specification so far can be summarized as follows:

[0657] This specification expands the payload of ADT packets. It expands the existing 1-7 byte payload of ADT size packets.

[0658] The extended ADT has payloads of 8, 10, 12, 14, 16, 18, 21, and 25 bytes.

[0659] When Fast FSK is applied, only a portion of the extended ADT payload is applied, not the entire amount.

[0660] Since the CEP interval cannot exceed 700ms during TPL, only ADT payloads of a size that can be applied within 700ms will be sent.

[0661] When the CEP interval is set to TPL, and the existing 250ms or 350ms intervals are applied for fast power control, only the ADT payload size, taking into account the timing requirement, will be sent.

[0662] The example shown in Figure 28 described above will now be explained in a different form using drawings.

[0663] Figure 36 is a sequential diagram of a method for transmitting wireless power, illustrating the example in Figure 28 in a different form.

[0664] As shown in Figure 36, the wireless power transmitter can receive SRQ (Specific Request) packets related to FSK (Frequency Shift Keying) from the wireless power receiver (S3610). Here, the SRQ packet may contain information about the number of cycles used for FSK.

[0665] Subsequently, the wireless power transmitter can send an ACK for the SRQ packet to the wireless power receiver (S3620).

[0666] The radio power transmitter can send ADT packets to the radio power receiver based on the number of cycles (S3630). Here, the maximum size of the ADT packet can be selected based on the number of cycles.

[0667] Furthermore, the maximum size of the ADT packet can be determined based on the number of cycles used in the FSK.

[0668] Here, as described above, the value of the number of cycles can be 512, 256, 128, or 64.

[0669] In this case, based on the value of the number of cycles being 512, the maximum size may be 7 bytes. Based on the value of the number of cycles being 256, the maximum size may be 16 bytes. Based on the value of the number of cycles being 128 or 64, the maximum size may be 25 bytes.

[0670] Here, as described above, the maximum size can be determined based on the number of cycles and the CE (control error) interval. The wireless power transmitter can transmit the ADT packet having the maximum size within the CE interval.

[0671] On the other hand, the ADT packet has a header, the value of the header is composed of hexadecimal numbers, and the number of units digits in the header value can be 6 or 7.

[0672] In this case, the size of the ADT packet may be any one of 1 byte, 8 bytes, 10 bytes, 12 bytes, 14 bytes, 16 bytes, 18 bytes, 21 bytes, or 25 bytes.

[0673] As described above, the wireless power transmitter receives an SRQ (specific request) packet from the wireless power receiver, and the SRQ packet may contain information regarding the number of cycles. The wireless power transmitter may receive the SRQ packet during the negotiation phase or the renegotiation phase.

[0674] In summary, ADT packets larger than 7 bytes are provided with ADT packets of 8, 10, 12, 14, 16, 18, 21, and 25 bytes in size. Each of these ADT packets can have an even / odd header. In other words, ADT packets larger than 7 bytes are provided with 16 types of ADT packets.

[0675] In this case, the wireless power transmitter may need to avoid using packets larger than the ADT packets permitted in each NCYCLE.

[0676] -NCYCLE=512 allows only up to 7 bytes.

[0677] -NCYCLE=256 allows only up to 16 bytes.

[0678] -NCYCLE=128 and / or 64 only allows up to 25 bytes.

[0679] For example, during the negotiation phase, the wireless power receiver can set NCYCLE to 128. The wireless power transmitter can use a 25-byte ADT packet for authentication, for example.

[0680] For example, once authentication is complete, the radio power receiver can anticipate a large load transient. The radio power receiver can then return to a 512-cycle timing using a renegotiated packet (e.g., RENEGO). In this case, the radio power transmitter can use an ADT packet that is the same size as or smaller than a 7-byte ADT.

[0681] The embodiments of this specification will be described again below from the perspectives of various entities.

[0682] The following drawings have been prepared to illustrate a specific example of this specification. The names of specific devices and signals / messages / fields shown in the drawings are provided as examples only, and the technical features of this specification are not limited to the specific names used in the following drawings.

[0683] Figure 37 is a sequence diagram of a method for transmitting wireless power from the perspective of a wireless power transmitter, according to one embodiment of this specification.

[0684] According to Figure 37, the wireless power transmitter can enter the power transfer phase related to transmitting the wireless power (S3710).

[0685] The wireless power transmitter can transmit ADT (auxiliary data transport) packets to the wireless power receiver during the power transfer phase (S3720).

[0686] Here, the wireless power transmitter can transmit the ADT packets to the wireless power receiver based on FSK (Frequency Shift Keying). The maximum size of the ADT packets can be determined based on the number of cycles used in the FSK.

[0687] Although not shown separately, a wireless power transmitter is provided. The wireless power transmitter may include a converter related to transmitting wireless power to a wireless power receiver and a communication / controller related to controlling the transmission of said wireless power. The wireless power transmitter may enter a power transfer phase related to transmitting said wireless power and transmit ADT (auxiliary data transport) packets to the wireless power receiver during the power transfer phase. The wireless power transmitter transmits the ADT packets to the wireless power receiver based on FSK (Frequency Shift Keying), and the maximum size of the ADT packets may be determined based on the number of cycles used in the FSK.

[0688] Figure 38 is a sequence diagram of a method for receiving wireless power from the perspective of a wireless power receiver, according to one embodiment of this specification.

[0689] According to Figure 38, the wireless power receiver can enter the power transfer phase related to receiving the wireless power (S3810).

[0690] The wireless power receiver can receive ADT (auxiliary data transport) packets from the wireless power transmitter during the power transfer phase (S3820).

[0691] Here, the wireless power receiver can receive the ADT packets from the wireless power transmitter based on FSK (Frequency Shift Keying). The maximum size of the ADT packets can be determined based on the number of cycles used in the FSK.

[0692] Although not otherwise shown, a wireless power receiver is provided. The wireless power receiver may include a power pickup unit related to receiving wireless power from a wireless power transmitter and a communication / controller related to controlling the reception of said wireless power. The wireless power receiver may enter a power transfer phase related to receiving said wireless power and receive ADT (auxiliary data transport) packets from the wireless power transmitter during the power transfer phase. The wireless power receiver receives said ADT packets from the wireless power transmitter based on FSK (Frequency Shift Keying), and the maximum size of said ADT packets may be determined based on the number of cycles used in said FSK.

[0693] The effects of this specification are described below.

[0694] As explained above, in subsequent wireless power transfer systems, Fast FSK can be introduced with reduced cycle counts (NCCLEs) of 256 in 512 and 64 in 128. When Fast FSK is used, fewer cycles are utilized to represent a single bit. This means that when Fast FSK is used, larger ADT packets can be defined while maintaining the same timing requirements.

[0695] This specification defines and provides a new maximum ADT packet size permitted in each NCYCLE when Fast FSK is used.

[0696] According to this specification, Fast FSK (NCYCLE=256,128,64) can increase the size of a single ADT packet that can be transmitted during a CE packet interval. This increased size of ADT packets per CE interval can then increase overall data throughput. Therefore, it may be possible to reduce application-level data transmission and reception time (e.g., authentication time).

[0697] In particular, this specification provides specific values ​​for the maximum ADT size that can be transmitted for each cycle based on 110 kHz, which corresponds to the slowest drive frequency in the standard. These specific values ​​are not just one of the many arbitrary sizes described above, but rather values ​​that take into account the interval between the ADT header and the CE packet.

[0698] Since the ADT size in this specification is limited to a maximum of 25 bytes, the wireless power transmitter can determine the maximum ADT packet size without modifying the existing header structure. Therefore, the data communication between the wireless power transmitter and wireless power receiver in this specification not only provides compatibility with existing standards but also offers the effect of easily calculating the ADT packet size in one byte.

[0699] Furthermore, according to this specification, when determining the header for ADT packets with a size greater than 7 bytes, existing ADT header rules can be applied. That is, according to this specification, it is possible to explicitly indicate that a packet is an ADT packet by using only some of the many header values. Therefore, according to this specification, extra data packet headers can be provided, which is advantageous for subsequent expansion of data packets.

[0700] The effects obtained through specific examples in this specification are not limited to those listed above. For example, there may be a variety of technical effects that a person having ordinary skill in the related art can understand or derive from this specification. Thus, the specific effects of this specification are not limited to those explicitly stated herein, but may include a variety of effects that can be understood or derive from the technical features of this specification.

[0701] The claims described herein may be combined in various ways. For example, the technical features of the method claims herein may be combined and embodied in an apparatus, or the technical features of the apparatus claims herein may be combined and embodied in a method. Furthermore, the technical features of the method claims and the technical features of the apparatus claims herein may be combined and embodied in an apparatus, or the technical features of the method claims and the technical features of the apparatus claims herein may be combined and embodied in a method.

Claims

1. In a method for a wireless power transmission system, the method is: Executed by a wireless power transmitter, This involves receiving an SRQ (specific request) packet from a wireless power receiver. The aforementioned SRQ packet contains information related to the number of cycles that make up one FSK (Frequency Shift Keying) bit, The aforementioned SRQ packet is received during the negotiation phase, This includes transmitting an ADT (auxiliary data transport) data packet to the wireless power receiver during the power transfer phase, The wireless power transmitter communicates with the wireless power receiver based on the FSK, The size of the ADT data packet is selected based on applying a floor function to a value obtained from the operating frequency and the number of cycles associated with the FSK. The aforementioned value increases when the number of cycles decreases. The aforementioned value increases as the operating frequency increases.

2. The method according to claim 1, wherein the number of cycles is 512, 256, 128, or 64.

3. Based on the fact that the number of cycles is 512, the size is 7 bytes. Based on the fact that the number of cycles is 256, the size is 16 bytes. The method according to claim 2, wherein the size is 25 bytes based on the number of cycles being 128 or 64.

4. In a wireless power transmitter, A converter related to transmitting wireless power to a wireless power receiver, A communicator / controller related to controlling the transmission of the wireless power is provided, The aforementioned wireless power transmitter receives an SRQ (specific request) packet from the wireless power receiver. The aforementioned SRQ packet contains information related to the number of cycles that make up one FSK (Frequency Shift Keying) bit, The aforementioned SRQ packet is received during the negotiation phase. The wireless power transmitter transmits an ADT (auxiliary data transport) data packet to the wireless power receiver during the power transfer phase. The wireless power transmitter communicates with the wireless power receiver based on the FSK, The size of the ADT data packet is selected based on applying a floor function to a value obtained from the operating frequency and the number of cycles associated with the FSK. The aforementioned value increases when the number of cycles decreases. The aforementioned value increases as the operating frequency increases in a wireless power transmitter.

5. In a method for a wireless power transmission system, the method is: Performed by a wireless power receiver, This involves sending an SRQ (specific request) packet to a wireless power transmitter. The aforementioned SRQ packet contains information related to the number of cycles that make up one FSK (Frequency Shift Keying) bit, The aforementioned SRQ packet is transmitted during the negotiation phase, This includes receiving ADT (auxiliary data transport) data packets from the wireless power transmitter during the power transfer phase, The wireless power receiver communicates with the wireless power transmitter based on the FSK, The size of the ADT data packet is selected based on applying a floor function to a value obtained from the operating frequency and the number of cycles associated with the FSK. The aforementioned value increases when the number of cycles decreases. The aforementioned value increases as the operating frequency increases.

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