Method for performing channel search and apparatus therefor

Abstract

The present disclosure relates to a method for performing a channel search in a wireless communication system and an apparatus therefor, and the method may comprise the steps of: transmitting a first packet in a first sub-event within an event, the first packet including first flag information indicating that the first packet includes information about at least one channel through which at least one second packet is transmitted, and information about at least one channel through which the at least one second packet is transmitted; transmitting the at least one second packet through the at least one channel in a second sub-event within the event; and receiving a third packet including channel information about the at least one channel in the second sub-event within the event.

Description

Method for performing channel scanning and device therefor

[0001] The present disclosure relates to a wireless communication system, and more particularly, to a method for performing channel search in a Bluetooth system and a device therefor.

[0002] The Bluetooth® standard has supported Bluetooth LE (Low Energy) since v4.0, and Bluetooth LE is used in various electronic devices such as smartphones and wireless earphones by reducing power consumption compared to other wireless communication technologies.

[0003] Recently, Bluetooth LE Higher Data Throughput (HDT), which supports higher data rates within Bluetooth LE, is being discussed. Bluetooth LE HDT is expected to be used in a wider range of applications, beyond just audio streaming, by supporting higher data rates and a wider range of data rates at lower power consumption.

[0004] The problem to be solved in the present disclosure is to provide a method and a device for updating channel information and a channel map in an event-driven manner rather than a periodic manner.

[0005] In addition, the problem to be solved in the present disclosure is to provide a method and a device for effectively performing rate adaptation in the next event or sub-event.

[0006] As a first aspect of the present disclosure, a method performed by a device in a wireless communication system is provided, the method comprising: transmitting a first packet in a first sub-event within an event, the first packet including first flag information indicating that information regarding at least one channel through which at least one second packet is transmitted is included in the first packet and information regarding at least one channel through which the at least one second packet is transmitted; transmitting the at least one second packet through the at least one channel in a second sub-event within the event; and receiving a third packet including channel information regarding the at least one channel in the second sub-event within the event.

[0007] As a second aspect of the present disclosure, a device configured to operate in a wireless communication system is provided, the device comprising: a transceiver; and at least one processor coupled to the transceiver, wherein the at least one processor is configured to transmit a first packet in a first sub-event within an event, the first packet including first flag information indicating that information regarding at least one channel through which at least one second packet is transmitted is included in the first packet and information regarding at least one channel through which the at least one second packet is transmitted, transmit the at least one second packet in the at least one channel in the second sub-event within the event, and receive a third packet including channel information regarding the at least one channel in the second sub-event within the event.

[0008] As a third aspect of the present disclosure, a computer-readable non-transitory storage medium is provided, the computer-readable non-transitory storage medium including a computer program configured to cause the device, when executed on a device, to perform an operation, the operation including transmitting a first packet in a first sub-event within an event, the first packet including first flag information indicating that information regarding at least one channel through which at least one second packet is transmitted is included in the first packet and information regarding at least one channel through which the at least one second packet is transmitted, transmitting the at least one second packet in the at least one channel in the second sub-event within the event, and receiving a third packet including channel information regarding the at least one channel in the second sub-event within the event.

[0009] Additionally or alternatively, the first flag information may be included in an extension header of the first packet.

[0010] Additionally or alternatively, the first flag information may have a value of 1.

[0011] Additionally or alternatively, the information about said at least one channel may include information indicating an interval between said at least one channel and information indicating a last channel on which said at least one second packet is transmitted among said at least one channel.

[0012] Additionally or alternatively, the information indicating the last channel through which the at least one second packet is transmitted may include a channel index of the last channel.

[0013] Additionally or alternatively, the starting channel through which the at least one second packet is transmitted may be determined as the channel selected for the second sub-event.

[0014] Additionally or alternatively, the second packet may include a preamble and a control header without a protocol data unit (PDU) header and a payload.

[0015] Additionally or alternatively, the third packet may be received after an inter frame space (IFS) from the end of transmission of the last packet of the at least one second packet.

[0016] Additionally or alternatively, the third packet may further include second flag information indicating that channel information for the at least one channel is included in the third packet.

[0017] Additionally or alternatively, the second flag information may be included in an extension header of the third packet.

[0018] Additionally or alternatively, the channel information for said at least one channel may include information indicating channel quality for the channel through which said second packet is transmitted.

[0019] Additionally or alternatively, the third packet may further include information indicating a starting channel on which the at least one second packet is transmitted among the at least one channel, information indicating an interval between the at least one channel, and information indicating a last channel on which the at least one second packet is transmitted.

[0020] According to the present disclosure, channel information can be effectively obtained for a required channel at a required time and a channel map can be effectively updated.

[0021] In addition, according to the present disclosure, transmission performance can be improved by effectively performing transmission rate adaptation in the next event or the next sub-event based on the acquired channel information.

[0022] Figure 1 illustrates a channel that can be used in the proposed method of the present disclosure.

[0023] Figure 2 illustrates frequency hopping that can be used in the proposed method of the present disclosure.

[0024] Figure 3 illustrates a CIS transmission that can be used in the proposed method of the present disclosure.

[0025] Figure 4 illustrates one sub-event.

[0026] Figure 5 illustrates a packet structure that can be used in the proposed method of the present disclosure.

[0027] Figure 6 illustrates a PDU header that can be used in the proposed method of the present disclosure.

[0028] FIG. 7 illustrates an extension header and a CE information block of a CE trigger packet according to method 1 of the present disclosure.

[0029] FIG. 8 illustrates an extension header and CR information block of a channel report packet according to method 1 of the present disclosure.

[0030] FIG. 9 illustrates a sub-event in which a CE signal and a channel report packet are transmitted according to method 1 of the present disclosure.

[0031] Figure 10 illustrates a flowchart of method 1 of the present disclosure.

[0032] Figures 11 to 14 illustrate examples to which method 1 of the present disclosure is applied.

[0033] Figure 15 illustrates a sub-event to which method 2-1 of the present disclosure is applied.

[0034] Figure 16 illustrates a flowchart of method 2-1 of the present disclosure.

[0035] Figure 17 illustrates a sub-event to which method 2-2 of the present disclosure is applied.

[0036] Figure 18 illustrates a flowchart of method 2-2 of the present disclosure.

[0037] Figure 19 illustrates an example in which method 2-1 of the present disclosure is applied.

[0038] Figure 20 illustrates an example in which method 2-2 of the present disclosure is applied.

[0039] Figure 21 illustrates probabilities that can be used in method 3 of the present disclosure.

[0040] Figures 22 and 23 illustrate examples in which method 1 and method 2-1 of the present disclosure are combined.

[0041] Figures 24 and 25 illustrate examples in which method 1 and method 2-2 of the present disclosure are combined.

[0042] Fig. 26 illustrates the structure of a device in which the proposed method of the present disclosure can be implemented.

[0043] Hereinafter, the present disclosure will be described in detail with reference to the attached drawings.

[0044] In the detailed description of this disclosure, if a detailed description of a related known technology is deemed to unnecessarily obscure the main point, such detailed description will be omitted. Furthermore, numbers (e.g., "first," "second," etc.) used in the detailed description are merely identifiers used to distinguish one component from another.

[0045] The terms used in this disclosure are selected from widely used, common terms, taking into account the functions of the disclosure. However, these terms may vary depending on the intentions of those skilled in the art, precedents, the emergence of new technologies, etc. Furthermore, in certain cases, terms may be arbitrarily selected by the applicant, in which case their meanings will be described in detail in the relevant description. Therefore, the terms used in this disclosure should not be defined simply as names, but rather based on the meanings of the terms and the overall content of the disclosure.

[0046] Singular expressions may include plural expressions unless the context clearly indicates otherwise. Terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art described herein. Furthermore, terms containing ordinal numbers, such as "first" or "second," used herein may be used to describe various components, but such components should not be limited by such terms. Such terms are used solely to distinguish one component from another.

[0047] When a part of the specification is said to "include" a component, this does not exclude other components, but rather implies the inclusion of other components, unless otherwise specifically stated. Furthermore, terms such as "unit (or part)" and "module" used in the specification mean a unit that processes at least one function or operation, which may be implemented in hardware, software, or a combination of hardware and software.

[0048] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings so that those skilled in the art can easily practice the present disclosure. However, the present disclosure may be implemented in various different forms and is not limited to the embodiments described herein. In addition, in the drawings, parts that are not related to the description are omitted to clearly explain the present disclosure, and similar parts are designated with similar reference numerals throughout the specification. In addition, the reference numerals used in each drawing are only for the purpose of describing each drawing, and different reference numerals used in different drawings do not indicate different elements.

[0049] Throughout the specification, when a part is said to be "connected" to another part, this includes not only "directly connected" or "physically connected," but also "electrically connected" with another element in between. In this disclosure, the terms "transmit," "receive," and "communicate" include both direct and indirect communication. Furthermore, when a part is said to "include" or "comprise" a component, this does not exclude other components, but rather includes other components, unless otherwise specifically stated.

[0050] Throughout this disclosure, unless specifically stated otherwise, “or” is inclusive and not exclusive. Thus, unless expressly indicated otherwise or the context dictates otherwise, “A or B” can refer to “A, B, or both.” As used herein, the phrase “at least one of” or “one or more of” can mean that different combinations of one or more of the listed items can be used, or that only any one of the listed items is required. For example, “at least one of A, B, and / or C” can include any of the following combinations: A, B, C, A and B, A and C, B and C, or A and B and C. As used herein, the expression “at least one of A, B, or C” can refer to “A,” “B,” “C,” “A and B,” “A and C,” “B and C,” “all of A, B, and C,” or variations thereof.

[0051] In one embodiment of the present disclosure, "connection relationship" may include the meaning of "connection relationship," "inclusion relationship," "attachment relationship," or "matching relationship." For example, "connected" may include the meaning of "connected," "inclusion," "attachment," or "matched." In one embodiment of the present disclosure, "connection" may include the meaning of data communication being possible, either wired or wireless. For example, "A and B are connected" may include the meaning that A and B are capable of data communication, i.e., can transmit and receive data with each other.

[0052] Although the present disclosure is described based on the Bluetooth® LE (Low Energy) HDT (Higher Data Throughput) specification, the present disclosure is not limited to the Bluetooth LE HDT specification and may be equally / similarly applied to other similar communication standards. For clarity of explanation in the present disclosure, a device supporting the Bluetooth LE HDT specification may be referred to as a device. However, the device of the present disclosure may be a device supporting other similar communication standards. In addition, a system supporting the Bluetooth LE specification in the present disclosure may be referred to as a Bluetooth LE system, and a system supporting the Bluetooth LE HDT specification may be referred to as a Bluetooth LE HDT system. In the present disclosure, Bluetooth LE and Bluetooth LE HDT may be collectively referred to as Bluetooth.

[0053] In the present disclosure, a device transmitting data may be referred to as a first device, and a device receiving data may be referred to as a second device. For example, the first device may be a central device (e.g., a laptop computer, a smartphone, etc.) and the second device may be a peripheral device (e.g., wireless earphones, a wireless headset, a smartwatch, etc.). However, the present disclosure is not limited thereto and may be applied in the same / similar manner even when the first device is a peripheral device and the second device is a central device.

[0054] In the present disclosure, a packet containing data (e.g., audio data) may be referred to as a data packet, and a data packet may be simply referred to as data. In the present disclosure, a packet containing ACK (acknowledgement) information may be referred to as an ACK packet, and an ACK packet may be simply referred to as ACK or ACK information. In the present disclosure, an octet means 8 bits and may be replaced with other terms such as a byte. In the present disclosure, the fact that information is arranged in octet units may mean that the information has a number of bits that is a multiple of 8.

[0055] A. Channel Structure

[0056] In a Bluetooth system, 40 channels can be used in the 2.4 GHz band, spaced 2 MHz apart. The channels may be referred to as radio frequency (RF) channels or physical channels. For example, each of the 40 channels may have a channel index from 0 to 39, which may indicate a 2 MHz band channel from 2400 MHz to 2480 MHz. For example, among the 40 channels, three channels (e.g., channel indices 37, 38, and 39) may be primary advertising channels used for initial advertising, and the remaining 37 channels (e.g., channel indices 0 to 36) may be general-purpose channels used for most data communications. The primary advertising channels may be referred to simply as advertising channels, and the general-purpose channels may be referred to as data channels.

[0057] Figure 1 illustrates a channel that can be used in the proposed method of the present disclosure.

[0058] A device can transmit and / or receive advertising packets through an advertising channel to search for other devices to connect to, and establish a connection with the other devices. After the device establishes a connection with the other device, the device can transmit and / or receive data with the other device using a data channel. In the present disclosure, establishing a connection may have the same meaning as creating a connection, and may be used interchangeably.

[0059] In the present disclosure, a device that transmits an advertisement packet so that other devices can scan may be referred to as a broadcaster, and a device that scans an advertisement channel to receive an advertisement packet from the broadcaster may be referred to as an observer. In the present disclosure, a device that initiates and / or requests connection establishment may be referred to as a central (or central device), and a device that accepts connection establishment initiated and / or requested by the central may be referred to as a peripheral (or peripheral device). After a connection is established, the central may be referred to as a master (or master device), and the peripheral may be referred to as a slave (or slave device).

[0060] For example, the central device may be a device with relatively large computing power and / or computing resources, and the peripheral devices may be devices with relatively small computing power and / or computing resources. As a non-limiting example of the present disclosure, the central device may be a laptop computer, a smartphone, etc., and the peripheral devices may be wireless earphones, a wireless headset, a smartwatch, etc. In a typical application, the central device may transmit data (e.g., an audio stream) to the peripheral devices. However, the present disclosure allows not only the central device to transmit data to the peripheral devices, but also the peripheral devices to transmit data to the central device.

[0061] B. Interference Control

[0062] In Bluetooth systems, frequency hopping can be used to avoid interference between devices. After establishing a connection, a device can transmit and / or receive data by performing frequency hopping across data channels (e.g., 37 channels corresponding to channel indices 0 to 36 in FIG. 1).

[0063] Figure 2 illustrates frequency hopping that may be used in the proposed method of the present disclosure. As illustrated in Figure 2, a device may perform frequency hopping on a channel-by-channel basis, and frequency hopping may be referred to as channel hopping.

[0064] When performing frequency hopping, the next channel may be determined based on a channel selection algorithm (CSA). For example, a Bluetooth LE system supports channel selection algorithm #1 or channel selection algorithm #2. Since the algorithms are described in detail in the Bluetooth Core Specification v5.4, a detailed description thereof is omitted in this disclosure, and the entire contents of the Bluetooth Core Specification v5.4 are incorporated herein by reference. In this disclosure, only channel selection algorithm #1 or channel selection algorithm #2 may be used, and other channel selection algorithms may be used.

[0065] A channel selection algorithm can be selected when establishing a connection between the central and peripheral devices. In channel selection algorithm #1, channels to be used for frequency hopping can be sequentially selected when establishing a connection, while in channel selection algorithm #2, channels to be used for frequency hopping can be calculated using a predefined algorithm between the central and peripheral devices. The channels selected by calculation in channel selection algorithm #2 may appear semi-random and can be effective in avoiding interference with data channels used for connections of other devices.

[0066] Referring to FIG. 2, the first central can frequency hop data channels selected by a channel selection algorithm after establishing connection 1 with the first peripheral, and the second central can frequency hop data channels selected by a channel selection algorithm after establishing connection 2 with the second peripheral. Since data can be transmitted and / or received using different channels in connection 1 between the first central and the first peripheral and connection 2 between the second central and the second peripheral through frequency hopping, interference can be effectively avoided. FIG. 2 is merely an example and FIG. 2 does not limit the present disclosure.

[0067] Channels likely to experience transmission errors can be avoided in channel selection algorithms (e.g., channel selection algorithm #1 or channel selection algorithm #2). For this purpose, a channel map can be used. The channel map can indicate the status of 37 data channels as good or bad. The classification of good and bad channels can be determined by the implementation, and various channel classification methods can be used, such as based on the signal-to-noise ratio (SNR) or packet error rate (PER). Data channels classified as good can be used for data communication and frequency hopping. If a data channel selected by the channel selection algorithm is classified as bad in the channel map, a new data channel can be selected using a channel remapping procedure. The channel remapping procedure can refer to a procedure for remapping a bad data channel to one of the good data channels.

[0068] A device can generate a channel map when establishing a connection, and update the channel map periodically (e.g., approximately 600 ms) during the connection. For example, the device can perform channel sensing on data channels (e.g., 37 data channels) during connection establishment or at regular intervals in idle slots, classify the channels according to a channel classification method, and generate or update the channel map. As an example that is not limiting to the present disclosure, the central unit can update the channel map and provide the updated channel map to the peripherals. This allows the central unit and the peripherals to share the channel map and select a data channel for frequency hopping using the channel map and a channel selection algorithm.

[0069] C. HDT (Higher Data Throughput) transmission

[0070] In a Bluetooth LE system, devices can determine a data transmission rate when establishing a connection. For example, in a Bluetooth LE system, one of LE 1M, LE 2M, and LE Coded can be selected regarding the transmission rate. LE 1M supports a transmission rate of 1 Mbps (megabits per second), LE 2M supports a transmission rate of 2 Mbps, and LE Coded supports 500 Kbps (kilobits per second) or 125 Kbps depending on forward error correction (FEC). In a Bluetooth LE system, devices can determine a transmission rate when establishing a connection and then perform data communication regardless of the binary channel condition of good or bad based on the determined transmission rate.

[0071] In the Bluetooth LE HDT system, HDT2, HDT3, HDT4, HDT6, and HDT7.5 are supported in terms of transmission rates, which represent transmission rates of 2 Mbps, 3 Mbps, 4 Mbps, 6 Mbps, and 7.5 Mbps, respectively. In the Bluetooth LE HDT system, a device can change the transmission rate for data communication even after a connection is established. The transmission rate can be indicated by the RI (Rate Indicator) field of the control header of a packet transmitted by the device (e.g., see “E. Packet Structure” of the present disclosure), and a modulation scheme, a coding rate, and a puncturing scheme can be predefined for each transmission rate. Therefore, when the device receives a packet, the device can identify the transmission rate through the RI field of the control header of the received packet, and decode the packet based on the modulation scheme, coding rate, and puncturing scheme corresponding to the identified transmission rate.

[0072] Table 1 shows examples of transmission rates, RI fields, modulation schemes, coding rates, and puncturing schemes according to the Bluetooth LE HDT specification. For example, referring to Table 1, HDT2 and HDT3 can use pi / 4-QPSK (quadrature phase shift keying), HDT4 can use 8PSK (phase shift keying), and HDT6 and HDT7.5 can use 16QAM (quadrature amplitude modulation). In Table 1, XXX in 0bXXX represents a 3-bit bit value.

[0073] If the value of the RI field is 0b000 (or a value of 0), the RI field may indicate that the packet is a short format packet, and the packet may not have a PDU header and payload (e.g., see “E. Packet Structure” of the present disclosure).

[0074] [Table 1]

[0075]

[0076] In a Bluetooth LE HDT system, since various transmission rates can be used for each channel, it may be effective to classify the channel into various states according to the transmission rate rather than classifying the channel into a binary state of good or bad. For example, assuming that an SNR value is used to classify the channel, a method may be used to classify the channel into at least five states by dividing the SNR value into at least five sections. As a more specific example, an SNR value may be obtained for the channel in units of 1 dB (decibel), and the channel may be classified as shown in Table 2. Referring to Table 2, if the acquired SNR value is in the first section, the channel may be classified into a state for HDT2, if the acquired SNR value is in the second section, the channel may be classified into a state for HDT3, if the acquired SNR value is in the third section, the channel may be classified into a state for HDT4, if the acquired SNR value is in the fourth section, the channel may be classified into a state for HDT6, and if the acquired SNR value is in the fifth section, the channel may be classified into a state for HDT7.5.

[0077] [Table 2]

[0078]

[0079] In a Bluetooth LE HDT system, a device (e.g., a central) can create or update a channel map based on multiple channel classifications rather than binary channel classifications. Furthermore, the device can perform frequency hopping using a channel map based on multiple channel classifications. For example, if a channel is classified as HDT2 in the channel map, the device can transmit data at a data rate of 2 Mbps on the channel during frequency hopping. For example, if a channel is classified as HDT3 in the channel map, the device can transmit data at a data rate of 3 Mbps on the channel during frequency hopping. For example, if a channel is classified as HDT4 in the channel map, the device can transmit data at a data rate of 4 Mbps on the channel during frequency hopping. For example, if a channel is classified as HDT6 in the channel map, the device can transmit data at a data rate of 6 Mbps on the channel during frequency hopping. For example, a device may transmit data at a rate of 7.5 Mbps on a channel when frequency hopping if the channel is classified as HDT7.5 in the channel map.

[0080] As described above, a device can set the RI field of the control header of a packet transmitted through a channel to a corresponding transmission rate according to the channel classification, and a device receiving the packet can identify the transmission rate through the RI field and decode the packet by applying a modulation method, coding rate, and puncturing method corresponding to the transmission rate.

[0081] D. Isochronous stream

[0082] The Bluetooth LE HDT system supports isochronous streams (IS), such as connected isochronous streams (CIS) and broadcast isochronous streams (BIS). An ACK (acknowledgement) may be used for CIS, and an ACK may not be used for BIS. For example, a central unit (e.g., a smartphone) may be simultaneously connected to multiple peripherals (e.g., left / right wireless earphones), and the central unit may transmit multiple independent and synchronized data streams (e.g., audio streams) to each peripheral. In this example, each of the multiple independent and synchronized data streams may be referred to as an isochronous stream. Although the present disclosure focuses on CIS for clarity of description, the present disclosure is not limited to CIS and may be equally / similarly applied to other data streams (e.g., BIS).

[0083] Figure 3 illustrates a CIS that can be used in the proposed method of the present disclosure.

[0084] Referring to FIG. 3, an event may refer to an opportunity or time period for a device (e.g., a central device, a peripheral device) to transmit and / or receive data. An event may occur at regular intervals. An event may include one or more sub-events. An event may start at a point referred to as an anchor point and end at the end of the last sub-event. Alternatively, an event may end through signaling between devices. As a non-limiting example of the present disclosure, if a CIS includes an audio stream, an event may be a time unit for transmitting one audio frame, and a sub-event may be a frequency hopping unit and / or a retransmission unit of audio data.

[0085] Anchor points can be set to have a regular interval, and the start times of sub-events can also be set to have a regular interval. For example, the interval between anchor points can be referred to as an ISO_Interval, which can be a multiple of 1.25 ms in the range of 5 ms (milliseconds) to 4 s (seconds). The interval between the start times of sub-events can be referred to as a Sub_Interval. Since ACK can be used in CIS, the Sub_Interval can be set to be greater than or equal to, for example, the sum of the time it takes to transmit a full-sized packet (e.g., a data packet) from the central to the peripheral, the time it takes to transmit a full-sized packet (e.g., an ACK packet) from the peripheral to the central, the time interval between two consecutive packets on the same channel index, and the minimum sub-event space (MSS). The time interval between two consecutive packets on the same channel index may be referred to as the inter-frame space (IFS), and may be, for example, 150 microseconds (us). For example, the MSS may be 150 microseconds.

[0086] Anchor points, ISO_Interval, Sub_Interval, number of subevents (NSE) within an event (e.g., N in Figure 3), etc. can be determined through negotiation between devices when establishing a connection.

[0087] Figure 4 illustrates one sub-event.

[0088] In Fig. 4, C -> P (410) represents a packet transmitted from the central to the peripheral, P -> C (420) represents a packet transmitted from the peripheral to the central, T_IFS represents IFS (e.g., 150 us), and T_MSS represents MSS (e.g., 150 us). As mentioned above, Sub_Interval can be determined when establishing a connection between devices, and T_IFS can have a fixed value (e.g., 150 us). Since a packet in a Bluetooth system can have a variable length depending on the size of the payload, the remaining time (430) of the sub-event can exist depending on the time for transmitting and receiving packets between the central and the peripheral.

[0089] E. Packet Structure

[0090] As previously described, a device can transmit a packet in a sub-event. Fig. 5 illustrates a packet structure that can be used in the proposed method of the present disclosure. For example, the packet illustrated in Fig. 5 may be an HDT packet used in a Bluetooth LE HDT system.

[0091] Referring to FIG. 5, a packet may have one of three packet formats: a short format, format 0, and format 1. The short format may include a preamble and a control header (CONTROL). In the present disclosure, a short format packet may be referred to as a short packet. Format 0 includes a preamble and a control header, and may optionally additionally include a protocol data unit (PDU) header and / or a payload zone depending on the configuration of the control header. Format 1 includes a preamble, a control header, and a PDU header, and may optionally additionally include a payload zone depending on the configuration of the PDU header. In the present disclosure, for clarity of description, the payload zone may be simply referred to as a payload. In format 0, the payload may be transmitted and / or received as a single payload, whereas in format 1, the payload may be divided into multiple blocks and transmitted and / or received.

[0092] For example, a preamble may include a short training sequence (STS) repeated a predetermined number of times, a guard interval (GI), and a long training sequence (LTS) repeated a predetermined number of times. More specifically, the STS may be 2 microseconds long and repeated nine times, the GI may be 2 microseconds long, and the LTS may be 8.5 microseconds long and repeated twice. These preamble structures are merely exemplary, and preambles with other structures may also be used in the proposed method of the present disclosure.

[0093] For example, the control header may include the fields in Table 3. The control header may apply 1 / 2 coding rate and pi / 4-QPSK modulation without puncturing to ensure maximum protection. A device receiving the control header may verify the Header Error Check Field (HEC-C) and, if present, receive and decode the PDU header and / or payload if the verification passes.

[0094] [Table 3]

[0095]

[0096] In the example of Table 3, the PCA-A field may contain 24 to 39 bits of the physical channel address, and the NESN field may contain the three least significant bits (LSBs) of the next expected sequence number.

[0097] In the example of Table 3, as described above, the RI (rate indicator) field may indicate the transmission rate and / or modulation method, coding rate, and puncturing method of the packet (see "C. HDT (Higher Data Throughput) Transmission" of the present disclosure). For example, if the value of the RI field is 0 (or 0b000), the RI field may indicate that it is a short format, and the PDU header and payload may not be present. For example, if the value of the RI field is 1 (or 0b001), the RI field may indicate that the PDU header and payload have a data rate of 2 Mbps. For example, if the value of the RI field is 2 (or 0b010), the RI field can indicate that the PDU header and payload have a data rate of 3 Mbps for format 0, and that the PDU header has a data rate of 2 Mbps and the payload has a data rate of 3 Mbps for format 1. For example, if the value of the RI field is 3 (or 0b011), the RI field can indicate that the PDU header and payload have a data rate of 4 Mbps for format 0, and that the PDU header has a data rate of 3 Mbps and the payload has a data rate of 4 Mbps for format 1. For example, if the value of the RI field is 4 (or 0b100), the RI field can indicate that the PDU header and payload have a data rate of 6 Mbps for format 0, and that the PDU header has a data rate of 4 Mbps and the payload has a data rate of 6 Mbps for format 1. For example, if the value of the RI field is 5 (or 0b101), the RI field can indicate that the PDU header and payload have a data rate of 7.5 Mbps for format 0, and that the PDU header has a data rate of 4 Mbps and the payload has a data rate of 7.5 Mbps for format 1.The values ​​and meanings of the above RI fields are only examples and the values ​​and meanings of the RI fields may vary.

[0098] In the example of Table 3, the PFI field can indicate format 0 or format 1. That is, the PFI field can indicate whether the packet is transmitted in format 0 or format 1 (e.g., 0: format 0, 1: format 1, or vice versa). For example, if the PFI field indicates format 0, the control header can include a 9-bit PDU LEN field. For example, if the PFI field indicates format 1, the control header can include a 6-bit PDU HDR LEN field, a 2-bit PHY INT field, and a 1-bit RFU field. For example, if the PFI field and the RI field indicate the short format, the control header can include a 9-bit RFU field.

[0099] In the example of Table 3, the PDU LEN field can indicate the number of octets of the PDU header and payload. The PDU HDR LEN field can indicate the length of the PDU header in octets. In Format 1, the payload can be divided into PHY intervals, and a PHY interval can contain a specific number of symbols. The PHY INT field can indicate the size of the PHY interval for Format 1 (e.g., 0: 64 μs; 128 symbols, 1: 128 μs; 256 symbols, 2: 192 μs; 384 symbols, 3: 256 μs; 512 symbols, or other values ​​and meanings are also possible).

[0100] Figure 6 illustrates a PDU header that can be used in the proposed method of the present disclosure.

[0101] Referring to FIG. 6, the PDU header can include four parts: an initial octet, an Rx portion, a Tx portion, and an extended header. The initial octet can include an XHP field, an RxPP field, and a TxPP field, and can include fields whose meanings change depending on the packet type (varies field). For example, the XHP (extended header present) field can indicate whether an extended header is present (e.g., 0: absent, 1: present, or vice versa). For example, the RxPP (receive portion present) field can indicate whether an Rx portion is present (e.g., 0: absent, 1: present, or vice versa). For example, the TxPP (transmit portion present) field can indicate whether a Tx portion is present (e.g., 0: absent, 1: present, or vice versa).

[0102] In the example of FIG. 6, the Rx portion can be used for tentative acknowledgment and / or selective acknowledgment for payloads having sequence numbers NESN to NESN+3. The Tx portion can be used in Format 1 and can indicate which payload among the payloads having sequence numbers SN to SN+3 is being transmitted and information about the transmitted payload.

[0103] For example, if an extension header is present (e.g., if the XHP field of the PDU header indicates its presence), the extension header may include a flag indicating whether a feature information block is present. The flag indicating whether a feature information block is present may be referred to as a feature present flag, but may also be referred to by another name. If the feature present flag included in the extension header indicates the presence of the corresponding feature information block, the corresponding feature information block may follow the octets containing the flags in the extension header. The first bit of the extension header (e.g., bit 0) may indicate whether the current octet is the last octet containing the feature present flags (e.g., a value of 0 means the last octet, a value of 1 means there is a next octet containing the feature present flags, or vice versa). For example, if the first bit of the extension header indicates that the current octet is the last octet containing flags (e.g., the first bit of the extension header has a value of 0), the corresponding feature information blocks may be present sequentially according to the feature present flag. For example, if the first bit of the extension header indicates that the current octet is not the last octet containing feature presence flags (or that another octet containing feature presence flags exists) (e.g., if the first bit of the extension header has a value of 1), then another octet containing feature presence flags may be present sequentially.

[0104] As illustrated in FIG. 5, a short format packet does not include a PDU header and a payload. For example, a packet in format 0 contains only one payload, and the payload is not divided into blocks. For example, a packet in format 1 may contain up to four separate payloads, which may be divided into smaller blocks, and the blocks may be optionally acknowledged. Optionally, unacknowledged blocks may be retransmitted using a packet in format 1. For example, information about blocks to be transmitted or retransmitted in a packet may be indicated by the Tx portion of the PDU header. For example, ACK information about blocks in a packet may be indicated by the Rx portion of the PDU header. If the payload is not divided into blocks, the device may switch the format between format 0 and format 1 during initial transmission and retransmission.

[0105] F. Method of Proposal of the Present Disclosure

[0106] In a Bluetooth system, the channel map can be updated periodically. For example, the central unit can classify the used channels as good or bad and update the channel map at regular intervals (e.g., every 600 ms) to provide the updated channel map to the peripherals. However, if the channel map is updated periodically, there is a technical issue that transmission performance may be degraded because the channel status cannot be immediately detected even if the channel condition suddenly deteriorates during the period. In particular, in the case of a Bluetooth LE HDT system, although rate adaptation can be used to cope with changes in channel conditions, it can be highly inefficient if the channel status can only be updated periodically. Furthermore, in current Bluetooth systems, the central unit can initiate the channel map update procedure, while the peripherals cannot. Therefore, a method for triggering the channel map update procedure from the peripherals may be required.

[0107] To address the above technical issues, the present disclosure proposes a method for enabling a device to update channel information in an event-driven manner rather than periodically. For clarity, the process of transmitting a signal for acquiring channel information and / or receiving channel information to update channel information according to the proposed method of the present disclosure may be referred to as channel exploration (CE). Furthermore, the signal transmitted and / or received for acquiring channel information according to the proposed method of the present disclosure may be referred to as a CE signal, and the packet reporting the channel information may be referred to as a channel report packet.

[0108] Method 1 of the present disclosure proposes an explicit channel discovery signaling (CE signaling) method, and Method 2 of the present disclosure proposes an implicit channel discovery signaling (CE signaling) method.

[0109] According to the proposed method of the present disclosure, by explicitly signaling the timing for updating channel information and the channel for which to update channel information, it is expected that the technical effect of effectively obtaining channel information for a required channel at a required time and effectively updating a channel map can be achieved.

[0110] In addition, since the transmission rate can be adjusted for each channel in the Bluetooth LE HDT system, channel information within the coherence time can be effectively utilized. In particular, when a CIS stream for an LE Audio application is used, if channel information about channels to be used in the next event or the next sub-event can be acquired from the current event or the current sub-event, transmission performance can be improved by effectively performing transmission rate adaptation in the next event or the next sub-event. According to the proposed method of the present disclosure, the technical effect of effectively performing transmission rate adaptation in the next event or the next sub-event and thus improving transmission performance can be expected.

[0111] G. Method 1

[0112] As a first method of the present disclosure, a method for explicitly signaling channel exploration (CE) is proposed. Specifically, in method 1, for explicit signaling for channel exploration, a packet triggering channel exploration, a packet transmitted for acquiring channel information, a packet reporting channel information, and a method for transmitting and / or receiving these packets are proposed. For clarity of description in the present disclosure, a packet triggering channel exploration according to method 1 of the present disclosure (or indicating that channel exploration is performed according to the proposed method of the present disclosure) may be referred to as a CE trigger packet.

[0113] CE trigger packet

[0114] The CE trigger packet of Method 1 may include a flag indicating the presence or absence of a feature information block related to channel exploration according to the proposed method of the present disclosure (or a feature presence flag related to channel exploration). For clarity of description in the present disclosure, the feature information block related to channel exploration may be referred to as a CE information block, and the flag indicating the presence or absence of the CE information block (or a feature presence flag related to channel exploration) may be referred to as a CE flag or a CE bit.

[0115] For example, the CE flag may be 1 bit, and a first value (e.g., 1) may indicate that a CE information block is present, and a second value (e.g., 0) may indicate that a CE information block is not present (or the first value and the second value may be defined as different values). When a CE information block is present, the CE information block may include information about channels on which channel searching according to the present disclosure is performed (or information about at least one channel on which a CE signal according to Method 1 of the present disclosure is transmitted and / or received).

[0116] Channels on which channel search according to the present disclosure is performed can be determined based on the CE information block, and channel search can be performed. Accordingly, the CE flag (or CE bit) can indicate whether channel search according to the present disclosure is triggered. For example, if the CE flag has a first value (e.g., 1), it can indicate that channel search according to the present disclosure is triggered, and if the CE flag has a second value (e.g., 0), it can indicate that channel search according to the present disclosure is not triggered. The proposed method of the present disclosure can be applied even if the value of the CE flag is defined in the opposite way.

[0117] For example, the CE information block may include information regarding at least one channel on which the CE signal is transmitted. As a specific example, the CE information block may include information indicating an interval between at least one channel on which the CE signal is transmitted and information indicating a final channel on which the CE signal is transmitted. The starting channel on which the CE signal is transmitted may be determined as a channel selected (using a channel selection algorithm) for the sub-event on which the CE signal is transmitted.

[0118] FIG. 7 illustrates an extension header (710) and a CE information block (720) of a CE trigger packet (700) according to method 1 of the present disclosure. In the example of FIG. 7, 1b means 1 bit, 7b means 7 bits, 2b means 2 bits, and 6b means 6 bits. In the example of FIG. 7, only the extension header (710) and the CE information block (720) are illustrated for clarity of explanation, but the CE trigger packet (700) according to method 1 of the present disclosure may include a preamble and a control header (e.g., see “E. Packet Structure” of the present disclosure).

[0119] As described in “E. Packet Structure” of the present disclosure, the first bit (e.g., bit 0) (712) of the extension header (710) may indicate whether the current octet is the last octet containing a feature presence flag (714). The first bit (712) of the extension header may be referred to as Another Octet flag or Another Octet bit. If the Another Octet flag (712) has a second value (e.g., 0), it may indicate that the current octet is the last octet containing the flag (714), and if the Another Octet flag (712) has a first value (e.g., 1), it may indicate that another octet (not shown) containing a flag follows (or that the current octet is not the last octet containing the feature presence flag (714).

[0120] The feature presence flag (714) of the extension header (710) used in the Bluetooth LE HDT system may include Stop, Empty, CTE, and LQ. The Stop flag (or Stop bit) may only be present in an asynchronous connectionless (ACL) packet, and may indicate that the receiver of the packet should not transmit payload data until it receives another packet. The Empty flag (or Empty bit) may indicate whether the current PDU is an empty PDU, and may only be present in a CIS packet using format 0 without payload data. The CTE flag (or CTE bit) may indicate whether the packet has a CTE (constant tone extension) field. The LQ (link quality) flag (or LQ bit) can indicate the presence of two octets indicating link quality, the first of which can indicate the transmit signal strength indicator (TSSI) of the current packet, and the second of which can indicate the received signal strength indicator (RSSI) of the last packet received.

[0121] A CE trigger packet (700) according to method 1 of the present disclosure may include a CE flag (or CE bit) (716) in the extended header (710). As described above, the CE flag (716) may indicate the presence or absence of a CE information block (720) (e.g., a value of 0: absence, a value of 1: presence, or vice versa) and / or whether channel scanning according to the present disclosure is triggered (e.g., a value of 0: not triggered, a value of 1: triggered, or vice versa).

[0122] Channel discovery according to the present disclosure can be performed within a sub-event of an isochronous stream. For example, channel discovery according to the present disclosure can be performed within an idle sub-event of an isochronous stream. As described in "D. Isochronous Stream" of the present disclosure, the anchor point, ISO_Interval, Sub_Interval, the number of sub-events (NSE) within an event, etc., can be determined through negotiation between devices when establishing a connection. For example, if packets are transmitted and / or received without error in CIS, data communication may not be performed in the remaining sub-events among the NSE sub-events within the event, and in the present disclosure, sub-events without data communication may be referred to as idle sub-events. Accordingly, if there is no more data to be transmitted within the event and (the index of the current sub-event + 1) is less than the number of sub-events (NSE) within the event, channel discovery according to the present disclosure can be triggered. That (the index of the current sub-event + 1) is less than the number of sub-events in the event can be expressed as (the index of the current sub-event + 1) < NSE. If there is still data to be transmitted in the event (e.g., retransmission data) and (the index of the current sub-event + 1) is equal to the number of sub-events (NSE) in the event, channel discovery according to the present disclosure cannot be triggered. That (the index of the current sub-event + 1) is equal to the number of sub-events (NSE) in the event can be expressed as (the index of the current sub-event + 1) = NSE, which can have the same meaning as that there are no sub-events left in the event, that the current sub-event is the last sub-event in the event, or that the number of sub-events used for data communication in the event is equal to NSE.

[0123] Referring back to FIG. 7, the CE information block (720) may include information (722) indicating an exploration channel gap and / or information (724) indicating an exploration end channel. For example, in the present disclosure, the information (722) indicating an exploration channel gap may be referred to as an Exploring Gap field, and the information (724) indicating an exploration end channel may be referred to as an End Channel Index field, although other names may be used. The exploration channel may refer to a channel through which a CE signal according to the proposed method of the present disclosure is transmitted and / or received. The exploration channel gap indicates the gap between exploration channels and may be expressed as a channel index value. The exploration start channel may refer to a start channel through which a CE signal according to the proposed method of the present disclosure is transmitted and may be expressed as a channel index value. The exploration end channel may refer to the last channel or end channel through which a CE signal according to the proposed method of the present disclosure is transmitted and may be expressed as a channel index value.

[0124] For example, the CE information block (720) may include one octet. As an example, the Exploring Gap field (722) may include 2 bits. As an example, the End Channel Index field (724) may include 6 bits. The CE information block (720), the Exploring Gap field (722), and the End Channel Index field (724) of the present disclosure are not limited to these examples and may be defined to have other numbers of octets and bits.

[0125] The Exploring Gap field (722) may indicate one of a plurality of exploration channel intervals depending on the bit value. For example, a bit value of 00 of the Exploring Gap field (722) may indicate exploration channel interval 1, a bit value of 01 may indicate exploration channel interval 2, a bit value of 10 may indicate exploration channel interval 3, and a bit value of 11 may indicate exploration channel interval 4. However, the present disclosure is not limited to this example, and the bit values ​​of the Exploring Gap field (722) may be defined to indicate other exploration channel intervals. For example, an exploration channel interval of n may mean that the next CE signal is transmitted on a channel having a channel index value that is n plus the current exploration channel index, and if the channel index plus n exceeds the maximum channel index, the channel index may be recalculated from 0. The End Channel Index field (724) may indicate an exploration end channel. For example, the End Channel Index field (724) may include an exploration end channel index.

[0126] The search start channel (or search start channel index) may be determined based on a channel selection algorithm (e.g., channel selection algorithm #1 or channel selection algorithm #2). The search start channel may refer to the starting channel on which the CE signal is transmitted. For example, if transmission of the CE signal begins on a channel selected according to the channel selection algorithm, the channel on which transmission of the CE signal begins may be determined as the search start channel.

[0127] For example, if the search start channel index is determined as n based on the channel selection algorithm, the search channel interval is indicated as k by the CE information block (720), and the search end channel index is indicated as m, the CE signal can be transmitted at search channel indices n, n+k, n+2k, n+3k, ..., m. If the search channel index exceeds the maximum value (e.g., 36), it can be wrapped around using a modulo operation (e.g., modulo 37).

[0128] Channel discovery according to the present disclosure can be triggered by a first device (e.g., a central) as well as a second device (e.g., a peripheral). Accordingly, both the first device and the second device can transmit a CE trigger packet (700). For example, the CE trigger packet transmitted by the first device can be a data packet, and the CE flag value of the extension header of the data packet can be set to a first value (e.g., 1), and a CE information block (720) can be included in the data packet. The CE trigger packet transmitted by the second device can be an ACK packet, and the CE flag value of the extension header of the ACK packet can be set to a first value (e.g., 1), and a CE information block (720) can be included in the ACK packet.

[0129] CE signal

[0130] The CE signal according to Method 1 of the present disclosure may refer to at least one packet transmitted for acquiring channel information. For example, the CE signal may be transmitted and / or received using at least one packet in a short format, and the short format packet may be referred to as a short packet in the present disclosure. As described in "E. Packet Structure" of the present disclosure, the short format may include a preamble and a control header without a PDU header and a payload. For example, the short packet may have a length of 69 us (microseconds) (in the time domain), but other lengths are also possible.

[0131] As described above, the CE signal according to method 1 of the present disclosure can be transmitted and / or received, for example, in an idle sub-event within an event, and the channels (indices and number of channels) for transmitting the CE signal can be determined based on a search start channel (index), a search channel interval, and a search end channel (index). Since short packets can be transmitted for each search channel, the CE signal can include as many short packets as the number of search channels. As described above, the search start channel (index) can be determined based on a channel selection algorithm, and, for example, a channel selected for a sub-event for transmitting the CE signal can be determined as the search start channel. The search channel interval and the search end channel (index) can be indicated by a CE information block.

[0132] A CE signal according to method 1 of the present disclosure can be transmitted by a first device (e.g., central) and received by a second device (e.g., peripheral).

[0133] Channel Report Packet

[0134] A channel report packet according to method 1 of the present disclosure may refer to a packet in which a device (or a second device) that has received a CE signal reports channel information to a device (or a first device) that has transmitted the CE signal. The channel report packet of method 1 may include a flag indicating whether a feature information block related to channel information reporting exists (or a feature presence flag related to channel reporting). For clarity of description in the present disclosure, the feature information block related to channel reporting may be referred to as a CR (channel report) information block, and the flag indicating whether a CR information block exists (or a feature presence flag related to channel reporting) may be referred to as a CR flag (or CR bit). For example, the CR flag may be 1 bit, and a first value (e.g., 1) may indicate that a CR information block exists after an extension header, and a second value (e.g., 0) may indicate that a CR information block does not exist (or the bit values ​​of the CR flag may be set to the opposite values). Channel information acquired (by the second device) based on the CE signal may be included in the CR information block.

[0135] FIG. 8 illustrates an extension header (810) and a CR information block (820) of a channel report packet (800) according to method 1 of the present disclosure. In the example of FIG. 8, 1b means 1 bit, 2b means 2 bits, 4b means 4 bits, 6b means 6 bits, and 7b means 7 bits. In the example of FIG. 8, only the extension header (810) and the CR information block (820) are illustrated to clarify the present disclosure, but the channel report packet (800) according to method 1 may include a preamble and a control header (e.g., see “E. Packet Structure” of the present disclosure).

[0136] The first bit (e.g., bit 0) (812) of the extended header (810) and the Stop, Empty, CTE, and LQ among the feature presence flags (814) may be the same as those described with reference to FIG. 7. Therefore, the description of the first bit (e.g., bit 0) (712) of FIG. 7 and the Stop, Empty, CTE, and LQ among the feature presence flags (714) are included herein by reference.

[0137] A channel report packet (800) according to the present disclosure may include a CE flag (or CE bit) (816) in an extension header (810). As described with reference to FIG. 7, the CE flag (816) may indicate whether a CE information block (720) exists (e.g., a value of 0: absence, a value of 1: presence, or vice versa) and / or whether channel discovery according to the present disclosure is triggered (e.g., a value of 0: not triggered, a value of 1: triggered, or vice versa). If channel discovery is not triggered by the channel report packet (800), the CE flag (816) may be set to indicate that the CE information block (720) does not exist (e.g., the value of the CE flag is set to 0). Alternatively, the channel report packet (800) may be set not to include the CE flag (816).

[0138] A channel report packet (800) according to the present disclosure may include a CR flag (or CR bit) (818) in an extended header (810). As described above, the CR flag (818) may indicate the presence or absence of a CR information block (820) (e.g., a value of 0: absence, a value of 1: presence, or vice versa).

[0139] Referring to FIG. 8, the CR information block (820) may include information (821) indicating a start channel for channels on which channel information is to be reported (or channels on which CE signals are transmitted and / or received), information (822) indicating a channel interval, and / or information (823) indicating an end channel. And / or, the CR information block (820) may include a Reserved for Future Use (RFU) bit (824). And / or, the CR information block (820) may include information (825) indicating a channel quality for a first channel or information (826) indicating a channel quality for a last channel, and may include padding bits (827) for aligning octets. For clarity of explanation in the present disclosure, information (821) indicating a start channel may be referred to as a Start Channel Index field, information (822) indicating a channel gap may be referred to as information indicating an exploration gap or may be referred to as an Exploring Gap field, information (823) indicating an end channel may be referred to as an End Channel Index field, information (825) indicating a channel quality for a first channel may be referred to as a First Channel Quality field, and information (826) indicating a channel quality for a last channel may be referred to as a Last Channel Quality field. Information (825) indicating a channel quality for a first channel to information (826) indicating a channel quality for a last channel may be collectively referred to as information indicating a channel quality for an Nth channel, and for clarity of explanation, the First Channel Quality field to the Last Channel Quality field may be referred to as an Nth Channel Quality field.

[0140] For example, the Start Channel Index field (821) of the CR information block (820) may include a start channel index for channels on which channel information is to be reported (or channels on which CE signals are transmitted and / or received). As an example, the Start Channel Index field (821) may be a 6-bit field. As an example, the start channel or start channel index associated with the Start Channel Index field (821) may be a search start channel or search start index (determined based on a channel selection algorithm) described with reference to FIG. 7. However, the present disclosure is not limited to these examples, and the Start Channel Index field (821) may include a different number of bits and the start channel or start channel index associated with the Start Channel Index field (821) may be defined in a different manner.

[0141] For example, the Exploring Gap field (822) of the CR information block (820) may include a value indicating an exploration interval (or channel gap) for channels for which channel information is to be reported (or channels on which CE signals are transmitted and / or received). As an example, the Exploring Gap field (822) may be a 2-bit field. As an example, the Exploring Gap field (822) may be set to the same value as the Exploring Gap field (722) of the CE information block (720). However, the Exploring Gap field (822) of the present disclosure is not limited to these examples and may have a different number of bits and may be defined in a different manner than the Exploring Gap field (722) of the CE information block (720).

[0142] For example, the End Channel Index field (823) of the CR information block (820) may include an end channel index for channels on which channel information is to be reported (or channels on which a CE signal is transmitted and / or received). As an example, the End Channel Index field (823) may be a 6-bit field, but may also be composed of a different number of bits. As an example, the end channel or end channel index associated with the End Channel Index field (823) may be a discovery end channel or discovery end channel index described with reference to FIG. 7. As an example, the End Channel Index field (823) may be set to the same value as the End Channel Index (724) of the CE information block (720). However, the present disclosure is not limited to these examples, and the End Channel Index field (823) may be defined with a different number of bits, and the end channel or end channel index associated with the End Channel Index field (823) may be defined in a different manner than the End Channel Index (724) of the CE information block (720).

[0143] When the Start Channel Index field (821), the Exploring Gap field (822), and the End Channel Index (823) of the CR information block (820) include channel information (e.g., exploration start channel index, exploration channel gap, exploration end channel index) related to the CE signal (e.g., see the related description of FIG. 7), the device (or the first device) transmitting the CE signal according to method 1 of the present disclosure can receive the CR information block (820) to obtain or identify the channel information related to the CE signal without storing the channel information related to the CE signal. When the device (or the first device) transmitting the CE signal according to method 1 of the present disclosure does not store the channel information related to the CE signal, there is an advantage of saving memory.

[0144] Alternatively, even if the Start Channel Index field (821), the Exploring Gap field (822), and the End Channel Index (823) of the CR information block (820) include channel information related to the CE signal, the device (or the first device) transmitting the CE signal according to method 1 of the present disclosure may store the channel information related to the CE signal. If the device (or the first device) transmitting the CE signal according to method 1 of the present disclosure stores the channel information related to the CE signal, the Start Channel Index field (821), the Exploring Gap field (822), and the End Channel Index (823) of the CR information block (820) may be used for error verification of the channel report packet (800).

[0145] Referring again to FIG. 8, for example, the RFU bit (824) of the CR information block (820) may be a field reserved for future use. For example, the RFU bit (824) may be a 2-bit field. For example, the RFU bit (824) may be set to bit value 00. For example, the RFU bit (824) may be set to bit value 11. However, the present disclosure is not limited to these examples, and the RFU bit (824) may be defined by a different number of bits or may be set to a different bit value. Alternatively, the CR information block (820) may be set not to include the RFU bit (824).

[0146] For example, the Nth Channel Quality field (825, 826) of the CR information block (820) may include a value indicating the channel quality of the Nth channel among the channels for reporting channel information (or the channels on which the CE signal is transmitted and / or received). As an example, the value indicating the channel quality may be a signal-to-noise ratio (SNR) value. As an example, the value indicating the channel quality may be a value indicating channel classification using a CE signal, and as a more specific example, may be a value representing a transmission rate (e.g., HDT2, HDT3, HDT4, HDT6, HDT7.5) described in "C. HDT Transmission" of the present disclosure. As an example, the Nth Channel Quality field (825, 826) may be a 4-bit field and may express the channel quality (or channel state) of the Nth channel in 16 values. However, the present disclosure is not limited to these examples, and the Nth Channel Quality field (825, 826) may be defined with a different number of bits and may be set to include values ​​other than SNR and transmission rate.

[0147] The number of Nth Channel Quality fields (825, 826) in the CR information block (820) can be determined based on the start channel (or start channel index), channel interval (or search interval), and end channel (or end channel index) of the channels for reporting channel information (or channels for transmitting and / or receiving CE signals). For example, assuming that the start channel index of the channels for reporting channel information (or channels for transmitting and / or receiving CE signals) is 16, the channel interval is 2, and the end channel index is 34, the number of Nth Channel Quality fields (825, 826) can be determined as 10 (=(34-16) / 2+1). In this example, if it is assumed that the Nth Channel Quality field (825, 826) is a 4-bit field and the number of Nth Channel Quality fields (825, 826) is determined to be 10, the Nth Channel Quality field (825, 826) may include 40 bits (= 4×10 bits). For example, the number of Nth Channel Quality fields (825, 826) may be determined based on the Start Channel Index field (821), the Exploring Gap field (822), and the End Channel Index field (823). Since the primary advertising channel (e.g., channel indexes 37, 38, 39) is not used for data, the primary advertising channel may be excluded from the channels for reporting channel information. The Nth Channel Quality field (825, 826) of the present disclosure is not limited to these examples and may be determined or set in other ways.

[0148] The CR information block (820) may be aligned in octet units. If necessary to align the CR information block (820) in octet units, padding bits (827) may be included in the CR information block (820). If the CR information block (820) is already aligned in octet units, the padding bits (827) may not be included in the CR information block (820). For example, if the total number of bits of information included in the CR information block (820) is not a multiple of 8, padding bits (827) may be included so that the total number of bits can be a multiple of 8, and if the total number of bits of information included in the CR information block (820) is a multiple of 8, padding bits (827) may not be included. As a more specific example, referring back to the example described in the Nth Channel Quality field (825, 826), since the number of Nth Channel Quality fields (825, 826) is 10, the total number of bits from the Start Channel Index field (821) to the Last Channel Quality field (826) may be 56 bits, and since they are aligned in octet units, the padding bit (827) is not included in the CR information block (820). As an example, the padding bit (827) may include a bit value of 0. As an example, the padding bit (827) may include a bit value of 1. The padding bit (827) of the present disclosure is not limited to these examples and may be defined to include other bit values.

[0149] FIG. 9 illustrates a sub-event in which a CE signal and a channel report packet are transmitted according to Method 1 of the present disclosure. FIG. 9 is provided solely to aid understanding of the present disclosure, and the present disclosure is not limited to the example of FIG. 9.

[0150] In the example of FIG. 9, it is assumed that a CE trigger packet (700) is transmitted and / or received in at least one sub-event (not shown) before a sub-event (910) within an event (not shown). Accordingly, a device (or a first device) transmitting a CE signal (920) in a sub-event (910) and a device (or a second device) receiving the CE signal can determine a search channel interval and a search end channel based on the CE information block (720) of the CE trigger packet (700) (e.g., see FIG. 7 and the related description). In addition, a channel selected in the sub-event (910) can be determined as a search start channel for the CE signal (920) (e.g., see FIG. 7 and the related description).

[0151] As described with reference to FIG. 7, the CE signal (920) according to method 1 of the present disclosure may be transmitted and / or received using at least one short packet (922) (or a packet in a short format described in “E. Packet Structure”). Accordingly, in the example of FIG. 9, the short packet (922) may have a length of 69 us. Transmitting (or receiving) the CE signal (920) according to method 1 of the present disclosure may include transmitting (or receiving) the short packet (922) per channel while switching channels from a search start channel to a search end channel at a search channel interval. For channel switching, a channel switching time (e.g., [x] us in FIG. 9) may exist between the short packets (922) of the CE signal (920). For example, the channel switching time may be determined according to the implementation of the device. For example, the channel switching time may be a frequency channel switching time (T) applied during channel sounding operation. FCS) and may be about 10 us to 15 us. As a specific example, assuming that the CE signal (920) is transmitted in 20 channels from the search start channel to the search end channel and the channel switching time is 15 us, the CE signal (920) may be transmitted and / or received over 1.665 ms (= 69×20 us + 15×19 us).

[0152] In the example of FIG. 9, a channel report packet (930) may be transmitted and / or received after an inter-frame space (IFS) after the last short packet (922) of the CE signal (920) is transmitted and / or received on the discovery end channel. As described in “D. Isochronous Stream” of the present disclosure, the IFS may be, for example, 150 us. For example, the second device may transmit the channel report packet (930) after the IFS after receiving the last short packet (922) of the CE signal (920) on the discovery end channel. As described with reference to FIG. 8, the channel report packet (930) may include channel information (e.g., the Nth Channel Quality fields (825, 826) of the CR information block (820)) for channels for which channel information is to be reported, and therefore, in the example of FIG. 9, the channel report packet (930) is indicated as channel information. Additionally, as described with reference to FIG. 8, the channel report packet (930) may include a CR flag (816), for example, in the channel report packet (930), the CR flag (816) may be set to a first value (e.g., 1) and the channel report packet (930) may include channel information (e.g., Nth Channel Quality field (825, 826)) within the CR information block (820).

[0153] FIG. 10 illustrates a flowchart of Method 1 of the present disclosure. While the example of FIG. 10 focuses on the operations of a first device (e.g., a central device), operations corresponding to the operations illustrated in FIG. 10 may be performed by a second device (e.g., a peripheral device). For example, a wireless communication system in which Method 1 of the present disclosure is performed may be a Bluetooth LE HDT system, but Method 1 of the present disclosure may also be applied to systems supporting other wireless communication standards.

[0154] Referring to FIG. 10, a first device may transmit or receive a first packet in a first sub-event within an event (e.g., see sub-events 1114 and 1116 of FIGS. 11 to 14), and a second device may receive or transmit (1010) a first packet in the first sub-event within the event. For example, the first packet may be a CE trigger packet (700) according to Method 1 of the present disclosure, and may include a CE flag (716) (e.g., set to a first value) and a CE information block (720). When a channel search according to the present disclosure is triggered by the first device, the first packet may be transmitted by the first device and received by the second device. Alternatively, when a channel search according to the present disclosure is triggered by the second device, the first packet may be transmitted by the second device and received by the first device.

[0155] A first device can transmit at least one second packet via at least one channel in a second sub-event within an event (including a first sub-event), and a second device can receive at least one second packet via at least one channel in the second sub-event (1020). For example, the second sub-event may correspond to a sub-event (910), the second packet may be a short format packet (922), and the at least one second packet may be a CE signal (920). The at least one channel may be identified based on a CE information block (720) transmitted or received in 1010 and a channel selected (by a channel selection algorithm) in the second sub-event.

[0156] The first device may receive a third packet (from the second device) in a second sub-event, and the second device may transmit a third packet (to the first device) in the second sub-event (1030). For example, the second sub-event may be a sub-event (910), the third packet may be a channel report packet (800, 930), and the third packet may include a CR flag (816) (e.g., set to a first value) and a CR information block (820).

[0157] Example where method 1 applies

[0158] FIGS. 11 to 14 illustrate examples to which Method 1 of the present disclosure is applied. The examples of FIGS. 11 to 14 are solely intended to aid understanding of the present disclosure, and the present disclosure is not limited to the examples of FIGS. 11 to 14. In the examples of FIGS. 11 to 14, it is assumed that ISO_Interval includes an event (1110), the number of sub-events (NSE) within the event (1110) is determined to be 4, and the event (1110) includes sub-events (1112, 1114, 1116, 1118). However, Method 1 of the present disclosure can be applied in the same / similar manner even when a different number of sub-events is used. For clarity of explanation, a sub-event in which a CE signal and a channel report packet are transmitted and / or received according to Method 1 of the present disclosure is denoted as a CE sub-event.

[0159] Also, in the examples of FIGS. 11 to 14, it is assumed that data (1120, 1122, 1124) and ACKs (1130, 1132, 1134) are transmitted and / or received using packets of format 1. As described in “E. Packet Structure” of the present disclosure, when format 1 is used, the payload may be divided into blocks, and a selective ACK (selective acknowledgment) may be transmitted and / or received for the divided blocks. Blocks that do not receive a selective ACK may be retransmitted using packets of format 1. However, method 1 of the present disclosure is not limited to the case of using packets of format 1, and method 1 of the present disclosure may be applied in the same / similar manner even when format 0 is used.

[0160] FIGS. 11 and 12 illustrate an operation of a first device (e.g., a central) to trigger channel search according to method 1 of the present disclosure, and FIGS. 13 and 14 illustrate an operation of a second device (e.g., a peripheral) to trigger channel search according to method 1 of the present disclosure.

[0161] FIG. 11 illustrates an operation of a first device to trigger channel search according to the present disclosure.

[0162] Referring to FIG. 11, a first device may perform an original transmission (1120) in a sub-event (1112). The original transmission may be replaced with other terms such as initial transmission. For example, the CE flag (716) of the packet (1120) for the original transmission may be set to a second value (e.g., 0), the packet (1120) may not include a CE information block (720), and may not trigger channel exploration according to method 1 of the present disclosure. For example, the CE flag (716) of the packet (1120) for the original transmission may be set to a first value (e.g., 1), the packet (1120) may include a CE information block (720), and may trigger channel exploration according to method 1 of the present disclosure. Assuming that the second device fails to receive at least one block of the original transmission in sub-event (1112), the second device may transmit an optional ACK (1130) to the first device in sub-event (1112).

[0163] If the first device receives a selective ACK (1130) in sub-event (1112), the first device may perform a retransmission (1122) for blocks for which it did not receive an ACK in sub-event (1114). The retransmission (1122) may be performed using a CE trigger packet (700) according to method 1 of the present disclosure. The retransmitted packet (1122) may include a CE flag (716), for example, the CE flag (716) may be set to a first value (e.g., 1), and the retransmitted packet (1122) may include a CE information block (720). Assuming that the second device fails to receive at least one of the retransmitted blocks in sub-event (1114), the second device may transmit a selective ACK (1132) to the first device in sub-event (1114).

[0164] If the first device receives a selective ACK (1132) in the sub-event (1114), the first device may perform a retransmission (1124) for blocks for which it did not receive an ACK in the sub-event (1116). Similar to the retransmission (1122), the retransmission (1124) may be performed using a CE trigger packet (700) according to method 1 of the present disclosure, and the retransmitted packet (1124) may include a CE flag (716), for example, the CE flag (716) may be set to a first value (e.g., 1), and the retransmitted packet (1124) may include a CE information block (720). Assuming that the second device successfully receives the retransmitted blocks in the sub-event (1116), the second device may transmit a full ACK (1134) to the first device in the sub-event (1116).

[0165] When the first device receives a full ACK (1134) in the sub-event (1116), the first device may transmit a CE signal (920) and the second device may transmit a channel report packet (930) in the sub-event (910), as described with reference to FIG. 9. The operations described with reference to FIG. 9 may be performed in the sub-event (910).

[0166] If the second device successfully receives the packet being transmitted or retransmitted in the sub-event (1112, 1114) and transmits a full ACK instead of a selective ACK (1130, 1132) and the first device receives the full ACK, then the first device may transmit a CE signal (920) and the second device may transmit a channel report packet (930) as described with reference to FIG. 9 in the next sub-event (1114, 1116). In this case, the sub-event (1114, 1116) may correspond to the sub-event (910) and the operation described with reference to FIG. 9 may be performed.

[0167] If it is assumed that the second device fails to receive the retransmitted packet (1124) in sub-event (1116), the second device may transmit a selective ACK (not shown) in sub-event (1116). If the first device receives the selective ACK (not shown) in sub-event (1116), the first device may perform a retransmission (not shown) for the non-ACKed blocks in sub-event (1118). Since sub-event (1118) is the last sub-event in event (1110), channel search according to the present disclosure cannot be performed in event (1110). Therefore, in the packet (not shown) retransmitted in sub-event (1118), the CE flag (716) of the extension header (710) may be set to a second value (e.g., 0).

[0168] FIG. 12 illustrates an operation of a first device to trigger channel search according to the present disclosure.

[0169] In the example of FIG. 12, the operation for sub-events (1112) and sub-events (1114) is the same as in the example of FIG. 11, and it is assumed that in sub-event (1116), the second device transmits an ACK (1134), but the first device fails to receive the ACK (1134) (or misses the ACK (1134)). Although the example of FIG. 12 assumes that the ACK (1134) is a full ACK, the example of FIG. 12 can be equally applied even when the ACK (1134) is a selective ACK.

[0170] Referring to FIG. 12, if the first device fails to receive the ACK (1134) in the sub-event (1116) (or misses the ACK (1134)), the first device may perform retransmission (1226) for the blocks retransmitted (1124) in the sub-event (1116) in the sub-event (1118). Since the sub-event (1118) is the last sub-event in the event (1110), the channel search according to the present disclosure cannot be performed in the event (1110). Accordingly, the CE flag (716) of the extension header (710) in the packet (1226) retransmitted in the sub-event (1118) may be set to a second value (e.g., 0) and the CE information block (720) may not be included.

[0171] Since the second device received the CE trigger packet (1124) and transmitted a full ACK (1134) in the sub-event (1116), the second device can expect to receive a short packet for a CE signal (not shown) in the sub-event (1118). However, since the packet (1226) retransmitted in the sub-event (1118) contains a payload for the retransmitted block, the RI field of the control header may be set to a non-zero value (e.g., see the description related to Table 1 and the description related to Table 3 of the present disclosure). Since the RI field of the control header of the short packet is set to a value of 0, the second device can identify that the first device failed to receive the ACK (1134) based on the value of the RI field of the control header of the packet (1226) retransmitted in the sub-event (1118) and can identify that the packet (1226) is a retransmitted packet.

[0172] FIG. 13 illustrates an operation of a second device to trigger channel search according to the present disclosure.

[0173] Referring to FIG. 13, the first device may perform an original transmission (1120) in a sub-event (1112). The original transmission may be replaced with other terms such as initial transmission. In the example of FIG. 13, it is assumed that the second device triggers a channel search according to the present disclosure and the first device does not trigger a channel search. Accordingly, the CE flag (716) of the packet (1120) for the original transmission is set to a second value (e.g., 0), and the packet (1120) may not include a CE information block (720) and may not trigger a channel search according to the proposed method of the present disclosure. Assuming that the second device fails to receive at least one block of the original transmission in the sub-event (1112), the second device may transmit an optional ACK (1130) to the first device in the sub-event (1112).

[0174] If the first device receives a selective ACK (1130) in sub-event (1112), the first device may perform a retransmission (1322) for blocks for which it did not receive an ACK in sub-event (1114). Similarly, in the example of FIG. 13, since it is assumed that the first device does not trigger channel exploration, the CE flag (716) of the retransmitted packet (1322) is set to a second value (e.g., 0), and the packet (1322) may not include a CE information block (720) and may not trigger channel exploration according to the proposed method of the present disclosure. Assuming that the second device successfully receives the retransmitted blocks in sub-event (1114), the second device may transmit a full ACK (1332) in sub-event (1114).

[0175] In sub-event (1114), the second device may set the CE flag (716) of the ACK packet (1332) to a first value (e.g., 1) to trigger channel exploration according to method 1 of the present disclosure, and may include a CE information block (720) in the ACK packet (1332).

[0176] When the first device receives a full ACK (1332) in the sub-event (1114), the first device may transmit a CE signal (920) and the second device may transmit a channel report packet (930) in the sub-event (910), as described with reference to FIG. 9. The operations described with reference to FIG. 9 may be performed in the sub-event (910).

[0177] FIG. 14 illustrates an operation of a second device to trigger channel search according to the present disclosure.

[0178] In the example of FIG. 14, the operation for the sub-event (1112) is the same as in the example of FIG. 13, and assumes that in the sub-event (1114), the second device transmits an ACK (1332), but the first device fails to receive the ACK (1332) (or misses the ACK (1332)). Since the second device triggers the channel search according to the present disclosure as in the example of FIG. 13, the CE flag (716) of the ACK packet (1332) is set to a first value (e.g., 1), and the ACK packet (1332) may include a CE information block (720). Although the example of FIG. 14 assumes that the ACK (1332) is a full ACK, the example of FIG. 14 may also be equally applicable to the case where the ACK (1332) is a selective ACK.

[0179] Referring to FIG. 14, if the first device fails to receive the ACK (1332) in the sub-event (1114) (or misses the ACK (1332)), the first device may perform a retransmission (1424) for the blocks retransmitted (1322) in the sub-event (1114) in the sub-event (1116). In the example of FIG. 14, assuming that the second device triggers the channel search according to the present disclosure, the CE flag (716) of the extension header (710) in the retransmitted packet (1424) may be set to a second value (e.g., 0).

[0180] Since the second device transmitted a full ACK (1332) in sub-event (1114), the second device can expect to receive a short packet for a CE signal in sub-event (1116). However, since the packet (1424) retransmitted in sub-event (1116) contains a payload for the retransmitted block, the RI field of the control header may be set to a non-zero value (e.g., see the description related to Table 1 and the description related to Table 3 of the present disclosure). Since the RI field of the control header of the short packet is set to a value of 0, the second device can identify that the first device failed to receive the ACK (1332) based on the value of the RI field of the control header of the packet (1424) retransmitted in sub-event (1116) and can identify that the packet (1424) is a retransmitted packet.

[0181] In sub-event (1116), the second device may again transmit a full ACK (1434). To trigger channel discovery according to the present disclosure, similar to packet (1332), the second device may set the CE flag (716) of the ACK packet (1434) to a first value (e.g., 1) and include a CE information block (720) in the ACK packet (1332).

[0182] When the first device receives a full ACK (1434) in the sub-event (1116), the first device may transmit a CE signal (920) and the second device may transmit a channel report packet (930) in the sub-event (910), as described with reference to FIG. 9. The operations described with reference to FIG. 9 may be performed in the sub-event (910).

[0183] H. Method 2

[0184] As method 2 of the present disclosure, a method for implicitly signaling channel exploration (CE) is proposed. Specifically, method 2 proposes method 2-1 for a first device to transmit a CE signal and method 2-2 for a second device to transmit a CE signal.

[0185] In method 2 of the present disclosure, the discovery channel may be determined as a channel used in a sub-event of the next event. For example, the channels used in the sub-events of the next event may be identified in advance based on a channel selection algorithm (e.g., channel selection algorithm #1, channel selection algorithm #2). Alternatively, in method 2 of the present disclosure, the discovery channel may be determined as a channel used in a sub-event of the current event. The number of channels used in the next event may be equal to the number (NSE) of sub-events in the event. The number of discovery channels to which method 2 of the present disclosure is applied may be determined to be equal to the number (NSE) of sub-events in the event. The discovery channel may refer to a channel through which a CE signal according to method 2 of the present disclosure is transmitted and / or received.

[0186] As in Method 1 (e.g., see FIG. 9 and the related description), the CE signal may be transmitted using short format packets (or short packets). However, in contrast to Method 1, the CE signal according to Method 2 of the present disclosure may include as many short packets as the number of sub-events (NSE) in an event, and the short packets may be transmitted and / or received on channels used in sub-events of the next event or on channels used in sub-events of the current event.

[0187] In method 2 of the present disclosure, channel discovery can be triggered based on the remaining time of a sub-event without explicit signaling (e.g., a CE trigger packet of method 1). For example, the remaining time of a sub-event can include the time taken to transmit and / or receive a data packet, the time taken to transmit and / or receive an ACK packet, and the inter-frame space (IFS) (e.g., 150 us) (between a data packet and an ACK packet) minus the time length of the sub-event (e.g., Sub_Interval).

[0188] Figure 15 illustrates a sub-event to which method 2-1 of the present disclosure applies. Figure 15 is solely intended to aid understanding of the present disclosure, and the present disclosure is not limited to the example of Figure 15.

[0189] Referring to FIG. 15, the remaining time (1560) of the sub-event (1510) may include the time obtained by subtracting the time taken to transmit and / or receive the data packet (1520), the time taken to transmit and / or receive the ACK packet (1530), and the inter-frame space (IFS) (e.g., 150 us) (between the data packet (1520) and the ACK packet (1530)) from the time length (e.g., Sub_Interval) of the sub-event (1510). The first device (or the second device) may determine whether the channel search according to the present disclosure is triggered based on the remaining time (1560) of the sub-event (1510) at the time point (1532) when the reception (or transmission) of the ACK packet (1530) ends.

[0190] For example, in method 2-1 where the first device transmits the CE signal (1540), since the second device must receive the CE signal (1540) and transmit the channel report packet (1550), channel search may be triggered if the remaining time (1560) of the sub-event (1510) is greater than or equal to the sum of the time taken to transmit and / or receive the CE signal (1540), the time taken to transmit and / or receive the channel report packet (1550), and the IFS (e.g., 150 us) (between the CE signal (1540) and the channel report packet (1550). If the remaining time (1560) of the sub-event (1510) is less than the sum of the time taken to transmit and / or receive the CE signal (1540), the time taken to transmit and / or receive the channel report packet (1550), and the IFS (e.g., 150 us) (between the CE signal (1540) and the channel report packet (1550)), then channel search may not be triggered. As in method 1 (e.g., see FIG. 9 and related description), there may be a channel switching time between short packets for the CE signal (1540).

[0191] For example, in Method 2-1, if Equation 1 is satisfied, channel search may be triggered, and if Equation 1 is not satisfied, channel search may not be triggered. In Equation 1, T_REM represents the remaining time (1560) of the sub-event (1510), T_SP represents the time length of the short packet (1542), NSE represents the number of sub-events in the event, T_CS represents the channel switching time between short packets (1542), T_CR represents the length of the channel report packet (1550), and IFS represents the inter-frame space (between the CE signal (1540) and the channel report packet (1550)). For example, as in Method 1 (e.g., see FIG. 9 and the related description), T_SP may be 69 us, T_CS may be determined depending on the implementation of the device, and IFS may be 150 us, although other values ​​are also possible. The length of the channel report packet may be variable.

[0192] [Mathematical Formula 1]

[0193] T_REM > T_SP×NSE + T_CS×(NSE - 1) + T_CR + IFS

[0194] As in Method 1 (e.g., see FIG. 8 and the related description), the channel report packet according to Method 2 of the present disclosure may include a CR flag (816) in the extended header (810), and may further include a channel information block (820) if the CR flag (816) indicates that a CR information block (820) exists (e.g., if the CR flag (816) has a first value). However, since the exploration channels in Method 2 of the present disclosure may be (implicitly) determined as channels used in sub-events of the next event or channels used in sub-events of the current event, the channel report packet according to Method 2 of the present disclosure may not include a Start Channel Index field (821), an Exploring Gap field (822), an End Channel Index field (823), and an RFU bit (824). Alternatively, the channel report packet according to method 2 of the present disclosure includes a Start Channel Index field (821), an Exploring Gap field (822), an End Channel Index field (823), and an RFU bit (824), wherein the Start Channel Index field (821), the Exploring Gap field (822), the End Channel Index field (823), and the RFU bit (824) may be set to a certain value (e.g., a bit value of 0 or a bit value of 1) or may be defined as an RFU field.

[0195] Fig. 16 illustrates a flowchart of Method 2-1 of the present disclosure. While the example of Fig. 16 focuses on the operations of a first device (e.g., a central device), operations corresponding to the operations illustrated in Fig. 16 may be performed by a second device (e.g., a peripheral device). The wireless communication system in which Method 2-1 of the present disclosure is performed may be, for example, a Bluetooth LE HDT system, but Method 2-1 of the present disclosure may also be applied to systems supporting other wireless communication standards.

[0196] Referring to FIG. 16, the first device (and the second device) can determine whether at least one first packet is transmitted in a sub-event based on the remaining time of the sub-event within the event (1610). For example, the sub-event of 1610 can be the sub-event (1510) of FIG. 15, the first packet can be a short packet (1542), the at least one first packet can be a CE signal (1540), the remaining time of the sub-event can be the remaining time (1560) of the sub-event (1510), and the first device (or the second device) can determine whether channel discovery according to the method 2-1 of the present disclosure is triggered based on the remaining time (1560) of the sub-event (1510) at the time point (1532) when the reception (or transmission) of the ACK packet (1530) ends (e.g., see FIG. 15 and the related description).

[0197] If the first device determines that at least one first packet is to be transmitted in the sub-event, the first device may transmit at least one first packet over at least one channel in the remaining time of the sub-event (1620). Similarly, if the second device determines that at least one first packet is to be transmitted in the sub-event, the second device may receive at least one first packet over at least one channel in the remaining time of the sub-event (1620). For example, if the remaining time (1560) of the sub-event (1510) is greater than or equal to the sum of the time it takes to transmit and / or receive the CE signal (1540), the time it takes to transmit and / or receive the channel report packet (1550), and the IFS (e.g., 150 us) (between the CE signal (1540) and the channel report packet (1550), a channel search may be triggered, and the first device (and the second device) may determine that at least one first packet is to be transmitted in the sub-event (1510).

[0198] The first device can receive a second packet including channel information for at least one channel in the sub-event, and the second device can transmit a second packet including channel information for at least one channel in the sub-event (1630). For example, the second packet can be a channel report packet (1550), and the first device can receive the second packet after an IFS from the end point of transmission of the CE signal (1540), and the second device can transmit the second packet after an IFS from the end point of reception of the CE signal (1540).

[0199] Figure 17 illustrates a sub-event to which method 2-2 of the present disclosure applies. Figure 17 is solely intended to aid understanding of the present disclosure, and the present disclosure is not limited to the example of Figure 17.

[0200] Referring to FIG. 17, the remaining time (1560) of the sub-event (1510) can be determined in the same manner as the example of FIG. 15, and the point in time (1532) for determining whether channel search according to the present disclosure is triggered can also be determined in the same manner.

[0201] In contrast to the example of FIG. 15, in Method 2-2 where the second device transmits the CE signal (1540), since the first device can obtain channel information based on the CE signal (1540) transmitted by the second device, the second device may not transmit a channel report packet. Accordingly, in Method 2-2, if the remaining time (1560) of the sub-event (1510) is greater than or equal to the time taken to transmit and / or receive the CE signal (1540), channel search may be triggered. If the remaining time (1560) of the sub-event (1510) is less than the time taken to transmit and / or receive the CE signal (1540), channel search may not be triggered. As in the example of FIG. 15, a channel switching time may exist between short packets (1542) for the CE signal.

[0202] For example, in Method 2-2, if Equation 2 is satisfied, channel search may be triggered, and if Equation 2 is not satisfied, channel search may not be triggered. In Equation 2, T_REM represents the remaining time (1560) of the sub-event (1510), T_SP represents the time length of the short packet (1542), NSE represents the number of sub-events in the event, and T_CS represents the channel switching time between short packets (1542). For example, as in Method 1 (e.g., see FIG. 9 and the related description), T_SP may be 69 us, and T_CS may be determined depending on the implementation of the device, but other values ​​may also be possible.

[0203] [Equation 2]

[0204] T_REM > T_SP×NSE + T_CS×(NSE - 1)

[0205] Fig. 18 illustrates a flowchart of Method 2-2 of the present disclosure. While the example of Fig. 18 focuses on the operations of a first device (e.g., a central device), operations corresponding to the operations illustrated in Fig. 18 may be performed by a second device (e.g., a peripheral device). For example, a wireless communication system in which Method 2-2 of the present disclosure is performed may be a Bluetooth LE HDT system, but Method 2-2 of the present disclosure may also be applied to systems supporting other wireless communication standards.

[0206] Referring to FIG. 18, the first device (and the second device) can determine whether at least one first packet is transmitted in a sub-event based on the remaining time of the sub-event within the event (1810). For example, the sub-event of 1810 can be the sub-event (1510) of FIG. 17, the first packet can be a short packet (1542), the at least one first packet can be a CE signal (1540), the remaining time of the sub-event can be the remaining time (1560) of the sub-event (1510), and the first device (or the second device) can determine whether channel discovery according to the method 2-2 of the present disclosure is triggered based on the remaining time (1560) of the sub-event (1510) at the time point (1532) when the reception (or transmission) of the ACK packet (1530) ends (e.g., see FIG. 17 and the related description).

[0207] If the first device determines that at least one first packet is transmitted in the sub-event, the first device can receive at least one first packet via at least one channel in the remaining time of the sub-event (1820). Similarly, if the second device determines that at least one first packet is transmitted in the sub-event, the second device can transmit at least one first packet via at least one channel in the remaining time of the sub-event (1820). For example, as described with reference to FIG. 17, if the remaining time (1560) of the sub-event (1510) is greater than or equal to the time it takes to transmit and / or receive the CE signal (1540), a channel search can be triggered, and the first device (and the second device) can determine that at least one first packet is transmitted in the sub-event (1510).

[0208] The first device may obtain channel information for at least one channel based on at least one first packet received in the sub-event (1830) (e.g., see FIG. 17 and related description). In method 2-2 of the present disclosure, since the first device obtains the channel information, the second device may not transmit a channel report packet.

[0209] Example where method 2 applies

[0210] FIG. 19 illustrates an example to which method 2-1 of the present disclosure is applied, and FIG. 20 illustrates an example to which method 2-2 of the present disclosure is applied. FIGS. 19 and 20 are only provided to aid understanding of the present disclosure, and the present disclosure is not limited to the examples of FIGS. 19 and 20. Similar to the examples of FIGS. 11 to 14, it is assumed that ISO_Interval includes an event (1110), the number of sub-events (NSE) within the event (1110) is determined to be 4, and the event (1110) includes sub-events (1112, 1114, 1116, 1118). However, method 2 of the present disclosure can be applied in the same / similar manner even when a different number of sub-events is used.

[0211] In the examples of FIGS. 19 and 20, it is assumed that data (1920, 1922, 1924) and ACKs (1930, 1932, 1934) are transmitted and / or received using packets of format 1. As described in “E. Packet Structure” of the present disclosure, when format 1 is used, the payload may be divided into blocks, and a selective ACK (selective acknowledgment) may be transmitted and / or received for the divided blocks. Blocks that do not receive a selective ACK may be retransmitted using packets of format 1. However, method 2 of the present disclosure is not limited to the case of using packets of format 1, and method 2 of the present disclosure may be applied in the same / similar manner even when format 0 is used.

[0212] Referring to FIG. 19, a first device may transmit a CE signal (1540) and a second device may transmit a channel report packet (1550) according to method 2-1 of the present disclosure. The first device may determine whether to transmit the CE signal (1540) based on the remaining time within the sub-events (1112, 1114, 1116) at the end time of reception of an ACK packet (1930, 1932, 1934) within the sub-events (1112, 1114, 1116) within the event (1110). Similarly, the second device can identify whether a CE signal (1540) is transmitted based on the remaining time within the sub-event (1112, 1114, 1116) at the end of transmission of an ACK packet (1930, 1932, 1934) within the sub-event (1112, 1114, 1116) within the event (1110). The remaining time within the sub-event (1112, 1114, 1116) and whether a CE signal is transmitted and / or received can be determined using the method described with reference to FIG. 15.

[0213] In the example of FIG. 19, the remaining time of the sub-event (1112, 1116) may be determined to be greater than the sum of the time it takes to transmit and / or receive the CE signal (1540), the time it takes to transmit and / or receive the channel report packet (1550), and the IFS (e.g., 150 us) (between the CE signal (1540) and the channel report packet (1550)), and a channel search may be triggered in the sub-event (1112, 1116). When the channel search is triggered, the first device may receive the channel report packet (1550) from the second device after the IFS after transmitting the CE signal (1540) in the sub-event (1112, 1116), and the second device may transmit the channel report packet (1550) to the first device after the IFS after receiving the CE signal (1540) in the sub-event (1112, 1116).

[0214] In the example of FIG. 19, assuming that the number of sub-events (NSE) within the event (1110) is four, the CE signal (1540) can be transmitted and / or received using four short packets on four channels. The four channels can be channels used in the sub-events of the next event (not shown) or channels used in the sub-events (1112, 1114, 1116, 1118) of the current event (1110). FIG. 19 is merely an example, and method 2-1 of the present disclosure can be equally applied to other numbers of sub-events.

[0215] In the example of FIG. 19, the remaining time of the sub-event (1114) may be determined to be less than the sum of the time it takes to transmit and / or receive the CE signal (1540), the time it takes to transmit and / or receive the channel report packet (1550), and the IFS (e.g., 150 us) (between the CE signal (1540) and the channel report packet (1550)), and channel search may not be triggered in the sub-event (1114). Since channel search is not triggered in the sub-event (1114), the CE signal (1540) and the channel report packet (1550) may not be transmitted and / or received.

[0216] If the first device receives a full ACK (1934) from the second device in sub-event (1116), the next sub-event (1118) may be an idle sub-event. Method 2-1 of the present disclosure may not be applied to an idle sub-event. Accordingly, channel search according to Method 2-1 of the present disclosure may be omitted in sub-event (1118).

[0217] Referring to FIG. 20, according to method 2-2 of the present disclosure, a second device may transmit a CE signal (1540), and a first device may obtain channel information based on the CE signal (1540). In method 2-2 of the present disclosure, transmission and / or reception of a channel report packet (1550) may be omitted. The second device may determine whether to transmit the CE signal (1540) based on the remaining time within the sub-events (1112, 1114, 1116) at the end time of transmission of an ACK packet (1930, 1932, 1934) within the sub-events (1112, 1114, 1116) within the event (1110). Similarly, the first device can identify whether a CE signal (1540) is transmitted based on the remaining time within the sub-event (1112, 1114, 1116) at the end of reception of an ACK packet (1930, 1932, 1934) within the sub-event (1112, 1114, 1116) within the event (1110). The remaining time within the sub-event (1112, 1114, 1116) and whether a CE signal is transmitted and / or received can be determined using the method described with reference to FIG. 17.

[0218] In the example of FIG. 20, the remaining time of the sub-event (1112, 1116) may be determined to be greater than the time taken to transmit and / or receive the CE signal (1540), and channel scanning may be triggered in the sub-event (1112, 1116). If the channel scanning is triggered, the second device may transmit the CE signal (1540) in the sub-event (1112, 1116), and the first device may obtain channel information based on the CE signal (1540).

[0219] In the example of FIG. 20, assuming that the number of sub-events (NSE) within the event (1110) is four, the CE signal (1540) can be transmitted and / or received using four short packets on four channels. The four channels can be channels used in the sub-events of the next event (not shown) or channels used in the sub-events (1112, 1114, 1116, 1118) of the current event (1110). FIG. 20 is merely an example, and method 2-2 of the present disclosure can be equally applied to other numbers of sub-events.

[0220] In the example of FIG. 20, the retransmission (1922) of the sub-event (1114) may take a long time to transmit due to the low coding rate applied. The remaining time of the sub-event (1114) may be determined to be less than the time required to transmit and / or receive the CE signal (1540), and channel scanning may not be triggered for the sub-event (1114). Since channel scanning is not triggered for the sub-event (1114), the CE signal (1540) may not be transmitted and / or received.

[0221] If the first device receives a full ACK (1934) from the second device in sub-event (1116), the next sub-event (1118) may be an idle sub-event. Method 2-2 of the present disclosure may not be applied to an idle sub-event. Accordingly, channel search according to Method 2-2 of the present disclosure may be omitted in sub-event (1118).

[0222] I. Method 3

[0223] Channel discovery according to method 1 of the present disclosure can be triggered by a first device (e.g., a central device) or a second device (e.g., a peripheral device). When channel discovery is triggered, a CE trigger packet (e.g., a CE flag set to a first value and including a CE information block) proposed in method 1 of the present disclosure can be transmitted by the first device or the second device. As method 3 of the present disclosure, a method for triggering channel discovery according to method 1 of the present disclosure is proposed.

[0224] Channel exploration according to Method 1 of the present disclosure may not be triggered solely by Method 3 of the present disclosure, but may be triggered in various ways and / or under various conditions. Therefore, Method 3 of the present disclosure may be understood as an alternative for triggering channel exploration according to Method 1. The channel exploration described in Method 3 of the present disclosure may refer to the channel exploration according to Method 1 of the present disclosure, and may be simply referred to as channel exploration for clarity of explanation.

[0225] When channel exploration is triggered using method 3 of the present disclosure, the first device (e.g., the central) may transmit a CE signal according to method 1 of the present disclosure in an idle sub-event within the event in which channel exploration is triggered (e.g., see FIG. 9 and related description). However, when there is no idle sub-event within the event in which channel exploration is triggered (e.g., when retransmission is performed even in the last sub-event within the event), channel exploration according to method 1 of the present disclosure may not be performed even when channel exploration is triggered using method 3 of the present disclosure.

[0226] In method 3 of the present disclosure, channel scanning may be triggered based on a probability obtained by using the difference between the last time the channel information was updated and the current time. For clarity of explanation, the last time the channel information was updated is represented by T_last, the current time is represented by T_current, the difference between the last time the channel information was updated and the current time is represented by T_current - T_last, and the probability is represented by Pr{CE}. In method 3 of the present disclosure, the probability may be determined to be 0 if T_current - T_last is less than or equal to a first time interval, and the probability may be determined to be 1 if T_current - T_last is greater than or equal to a second time interval. In method 3 of the present disclosure, when T_current - T_last is greater than the first time interval and less than the second time interval, the probability may be determined using a probability function. If the probability is 1, the channel scanning is always triggered, and if the probability is 0, the channel scanning is never triggered. If the probability is determined to be a value between 0 and 1, the channel scanning may be triggered with the determined probability value. For example, if the probability is determined to be 0.5, channel scanning can be triggered with a probability of 1 / 2.

[0227] For example, the first time interval may be a minimum time interval associated with channel information updates, and the second time interval may be a recommended time interval associated with channel information updates. The first and second time intervals may be predefined between devices or may be negotiated during connection establishment.

[0228] For example, the probability function Pr{CE} can have T_current - T_last as an input parameter. Additionally, in order to reflect the channel state when determining the probability, the probability function Pr{CE} can have a parameter representing the channel state as an input parameter. For clarity of explanation, the parameter representing the channel state can be expressed as Intensity. For example, Intensity can be determined based on at least one of the number of retransmissions, bit error rate, block error rate, and packet error rate. For example, as the channel state worsens, the need to update channel information increases, so Intensity can be determined such that the value of the probability function Pr{CE} is high. For example, as the channel state improves, the need to update channel information decreases, so Intensity can be determined such that the value of the probability function Pr{CE} is low. As a specific example, the channel condition can be identified as worsening as the number of retransmissions, bit error rate, block error rate, and packet error rate increase, and the channel condition can be identified as good as the number of retransmissions, bit error rate, block error rate, and packet error rate decrease.

[0229] Figure 21 illustrates probabilities that can be used in Method 3 of the present disclosure. Figure 21 is solely intended to aid understanding of the present disclosure, and the present disclosure is not limited to the example of Figure 21. In Figure 21, the first time interval is represented as MIN_CE_INTERVAL, and the second time interval is represented as RECOMMENDED_CE_INTERVAL.

[0230] Referring to FIG. 21, if T_current - T_last is less than or equal to the first time interval (MIN_CE_INTERVAL), the probability can be determined as 0, and if T_current - T_last is greater than or equal to the second time interval (RECOMMENDED_CE_INTERVAL), the probability can be determined as 1. If T_current - T_last is greater than the first time interval (MIN_CE_INTERVAL) and less than the second time interval (RECOMMENDED_CE_INTERVAL), the probability can be determined using a probability function.

[0231] The probability function according to method 3 of the present disclosure may have T_current - T_last and / or Intensity as input parameters. For example, it may be expressed as Pr{CE} = foo(T_current - T_last, Intensity), where foo(T_current - T_last, Intensity) indicates that it is a function that has T_current - T_last and Intensity as input parameters. As a more specific example, mathematical expression 3 may be used as the probability function. However, method 3 of the present disclosure is not limited to mathematical expression 3, and other probability functions may be used.

[0232] [Equation 3]

[0233]

[0234] As explained above, as the channel condition worsens, the Intensity value may be determined higher, and Pr{CE} may have a form with a high probability (e.g., 2110). As the channel condition improves, the Intensity value may be determined lower, and Pr{CE} may have a form with a low probability (e.g., 2120).

[0235] J. Combination of the proposed methods of the present disclosure

[0236] The proposed methods (method 1, method 2, method 3) of the present disclosure may be performed independently or at least two of them may be combined. For example, FIGS. 22 and 23 illustrate examples in which method 1 and method 2-1 of the present disclosure are combined, and FIGS. 24 and 25 illustrate examples in which method 1 and method 2-2 of the present disclosure are combined. For example, channel search according to method 1 of the present disclosure may be triggered according to method 3 of the present disclosure or may be triggered according to another method. In the examples of FIGS. 22 to 25, it is assumed that ISO_Interval includes an event (1110), the number of sub-events (NSE) within the event (1110) is determined to be 4, and the event (1110) includes sub-events (1112, 1114, 1116, 1118), but the same / similar application may be applied even when a different number of sub-events is used. For clarity of explanation, a sub-event in which a CE signal and a channel report packet according to method 1 of the present disclosure are transmitted and / or received is denoted as a CE sub-event.

[0237] FIG. 22 illustrates an example in which a first device triggers channel search according to method 1 of the present disclosure and the first device initiates channel search according to method 2-1 of the present disclosure.

[0238] Referring to FIG. 22, method 2-1 may be applied to sub-events (1112, 1114, 1116), and method 1 may be applied to sub-event (1118). In sub-event (1112), the remaining time of the sub-event (1112) may be identified as being less than the sum of the time taken to transmit and / or receive a CE signal, the time taken to transmit and / or receive a channel report packet, and the IFS (between the CE signal and the channel report packet), and the CE signal and the channel report packet according to method 2-1 may not be transmitted and / or received. In sub-events (1114, 1116), the remaining time of the sub-event (1114, 1116) can be identified as being greater than the sum of the time it takes to transmit and / or receive the CE signal, the time it takes to transmit and / or receive the channel report packet, and the IFS (between the CE signal and the channel report packet), and in sub-events (1114, 1116), the first device can transmit the CE signal according to method 2-1 and the second device can transmit the channel report packet according to method 2-1. Assuming that in sub-events (1114, 1116), a CE trigger packet (e.g., having a CE flag set to a first value and including a CE information block) is transmitted by the first device and sub-event (1118) is an idle sub-event, in sub-event (1118), the first device can transmit the CE signal according to method 1 and the second device can transmit the channel report packet.

[0239] FIG. 23 illustrates an example in which a second device triggers channel search according to method 1 of the present disclosure and a first device initiates channel search according to method 2-1 of the present disclosure.

[0240] Referring to FIG. 23, method 2-1 may be applied to sub-events (1112, 1114), and method 1 may be applied to sub-event (1116). In sub-event (1112), the remaining time of the sub-event (1112) may be identified as being less than the sum of the time taken to transmit and / or receive a CE signal, the time taken to transmit and / or receive a channel report packet, and the IFS (between the CE signal and the channel report packet), and the CE signal and the channel report packet according to method 2-1 may not be transmitted and / or received. In a sub-event (1114), the remaining time of the sub-event (1114) may be identified as being greater than the sum of the time it takes to transmit and / or receive a CE signal, the time it takes to transmit and / or receive a channel report packet, and the IFS (between the CE signal and the channel report packet), and in the sub-event (1114), the first device may transmit a CE signal according to method 2-1, and the second device may transmit a channel report packet according to method 2-1. Assuming that in the sub-event (1114), a CE trigger packet (e.g., having a CE flag set to a first value and including a CE information block) is transmitted by the second device, and the sub-event (1116) within the event (1110) is an idle sub-event, in the sub-event (1116), the first device may transmit a CE signal according to method 1, and the second device may transmit a channel report packet according to method 1, and in the sub-event (1116), the CE signal and the channel report packet according to method 2-1 may not be transmitted and / or received. Sub-event (1118) is also an idle event, but since channel exploration according to method 1 was performed in sub-event (1116), channel exploration according to method 1 may not be performed in sub-event (1118). Channel exploration according to method 2-1 may not be performed in idle sub-event (1118).

[0241] FIG. 24 illustrates an example in which a first device triggers channel search according to method 1 of the present disclosure and a second device initiates channel search according to method 2-2 of the present disclosure.

[0242] Referring to FIG. 24, method 2-2 may be applied to sub-events (1112, 1114, 1116), and method 1 may be applied to sub-event (1118). In sub-event (1112), the remaining time of the sub-event (1112) may be identified as being less than the time taken to transmit and / or receive a CE signal, and a CE signal and a channel report packet according to method 2-2 may not be transmitted and / or received. In sub-events (1114, 1116), the remaining time of the sub-events (1114, 1116) may be identified as being greater than the time taken to transmit and / or receive a CE signal, and in sub-events (1114, 1116), a second device may transmit a CE signal according to method 2-2, and a first device may obtain channel information based on the CE signal. Assuming that a CE trigger packet (e.g., having a CE flag set to a first value and including a CE information block) is transmitted by the first device in sub-events (1114, 1116) and that sub-event (1118) is an idle sub-event, in sub-event (1118), the first device may transmit a CE signal according to method 1 and the second device may transmit a channel report packet.

[0243] FIG. 25 illustrates an example in which a second device triggers channel search according to method 1 of the present disclosure and the second device initiates channel search according to method 2-2 of the present disclosure.

[0244] Referring to FIG. 25, method 2-2 may be applied to sub-events (1112, 1114), and method 1 may be applied to sub-event (1116). In sub-event (1112), the remaining time of the sub-event (1112) may be identified as being less than the time taken to transmit and / or receive a CE signal, and a CE signal and a channel report packet according to method 2-2 may not be transmitted and / or received. In sub-event (1114), the remaining time of the sub-event (1114) may be identified as being greater than the time taken to transmit and / or receive a CE signal, and in sub-event (1114), a second device may transmit a CE signal according to method 2-2, and a first device may obtain channel information based on the CE signal. Assuming that a CE trigger packet (e.g., having a CE flag set to a first value and including a CE information block) is transmitted by the second device in sub-event (1114) and that sub-event (1116) is an idle sub-event, the first device may transmit a CE signal according to method 1 and the second device may transmit a channel report packet in sub-event (1116), and a CE signal according to method 2-2 may not be transmitted and / or received in sub-event (1116). Sub-event (1118) is also an idle event, but since a channel search according to method 1 was performed in sub-event (1116), a channel search according to method 1 may not be performed in sub-event (1118). A channel search according to method 2-2 may not be performed in the idle sub-event (1118).

[0245] In addition to the examples of FIGS. 22 to 25, the proposed methods of the present disclosure can be combined and applied in various ways.

[0246] K. Device Structure

[0247] FIG. 26 illustrates the structure of a device (2600) in which the proposed method of the present disclosure can be implemented.

[0248] Referring to FIG. 26, a device (2600) may include a processor (2610), a transceiver (2620) including a receiver and / or a transmitter, and a memory (2630). The processor (2610), the transceiver (2620), and the memory (2630) may be operably coupled and configured to implement the proposed method of the present disclosure. The structure illustrated in FIG. 26 is an example, and a device that may implement the proposed method of the present disclosure may be configured in various structures. For example, the device may include more or fewer components than the components illustrated in FIG. 26. In addition, at least one of the processor (2610), the transceiver (2620), and the memory (2630) may be implemented in the form of a single chip.

[0249] The transceiver (2620) may be configured to transmit and receive signals with other devices. The signals may include, for example, packets carrying data and / or control information. To this end, the transceiver (2620) may include an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies and down-converts the frequency of a received signal. This is an example of the transceiver (2620), and the components of the transceiver (2620) are not limited to the RF transmitter and RF receiver.

[0250] Additionally, the transceiver (2620) can receive a signal through a wireless channel and output it to the processor (2610), and transmit the signal output from the processor (2610) through the wireless channel.

[0251] The memory (2630) can store programs and data required for the operation of the device (2600). In addition, the memory (2630) can store control information or data included in signals transmitted and / or received by the device (2600). The memory (2630) can be configured as a storage medium or a combination of storage media, such as a ROM, a RAM, a hard disk, a CD-ROM, and a DVD. In addition, there can be multiple memories.

[0252] The processor (2610) may control a series of processes so that the device (2600) can operate according to the proposed method of the present disclosure. For example, the processor (2610) may control each component of the device (2600) to configure and transmit a CE trigger packet, a CE signal, and / or a channel report packet. There may be a plurality of processors (2610), and the processors (2610) may perform component control operations of the device (2600) by executing a program stored in the memory (2630).

[0253] The methods described in the claims or specification of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

[0254] When implemented in software, a non-transitory computer-readable storage medium storing one or more programs (software modules) may be provided. The one or more programs stored in the non-transitory computer-readable storage medium are configured for execution by one or more processors within the device. The one or more programs include instructions that cause the device to execute the claims of the present disclosure or the proposed methods of the present disclosure.

[0255] These programs (software modules, software) may be stored in random access memory, non-volatile memory including flash memory, read only memory (ROM), electrically erasable programmable read only memory (EEPROM), magnetic disc storage device, compact disc ROM (CD-ROM), digital versatile discs (DVDs) or other forms of optical storage device, magnetic cassette. Or, they may be stored in a memory configured as a combination of some or all of these. In addition, each configuration memory may be included in multiple numbers.

[0256] Additionally, the program may be stored in an attachable storage device that is accessible via a communication network such as the Internet, an intranet, a local area network (LAN), a wide local area network (WLAN), a storage area network (SAN), or a combination thereof. Such a storage device may be connected to a device performing the proposed method of the present disclosure via an external port. Additionally, a separate storage device on the communication network may be connected to a device performing the proposed method of the present disclosure.

[0257] In the proposed method of the present disclosure described above, components included in the invention are expressed singularly or plurally, depending on the specific embodiments presented. However, the singular or plural expressions are selected to suit the presented situation for convenience of explanation, and the present disclosure is not limited to singular or plural components. Components expressed in plural may be composed of singular elements, or components expressed in singular may be composed of plural elements.

[0258] Meanwhile, the embodiments of the present disclosure disclosed in this specification and drawings are only specific examples to easily explain the technical contents of the present disclosure and to help the understanding of the present disclosure, and are not intended to limit the scope of the present disclosure. In other words, it will be apparent to a person having ordinary skill in the art to which the present disclosure pertains that other modified embodiments are possible based on the technical idea of ​​the present disclosure. In addition, the respective embodiments above can be combined and operated with each other as needed. For example, parts of one embodiment of the present disclosure and another embodiment can be combined with each other to operate a device. Although the above embodiments have been presented based on the Bluetooth LE HDT system, other modified embodiments based on the technical idea of ​​the above embodiments can be implemented with other systems, such as other Bluetooth systems developed in the future.

[0259] Meanwhile, the order of description in the drawings explaining the method of the present invention does not necessarily correspond to the order of execution, and the order of precedence may be changed or executed in parallel.

[0260] Alternatively, the drawings illustrating the method of the present invention may omit some components and include only some components within a scope that does not harm the essence of the present invention.

[0261] In addition, the method of the present invention may be implemented by combining some or all of the contents included in each embodiment within a scope that does not harm the essence of the invention.

[0262] Various embodiments of the present disclosure have been described above. The foregoing description of the present disclosure is for illustrative purposes only, and the embodiments of the present disclosure are not limited to the disclosed embodiments. Those skilled in the art will appreciate that the present disclosure can be readily modified into other specific forms without altering the technical spirit or essential characteristics of the present disclosure. The scope of the present disclosure is indicated by the claims described below rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present disclosure.

Claims

1. A method performed by a device in a wireless communication system, A step of transmitting a first packet in a first sub-event within an event, the first packet including first flag information indicating that information regarding at least one channel through which at least one second packet is transmitted is included in the first packet and information regarding at least one channel through which the at least one second packet is transmitted; a step of transmitting at least one second packet through at least one channel in a second sub-event within the event; and A method comprising the step of receiving a third packet including channel information for at least one channel in a second sub-event within the event.

2. In claim 1, A method wherein the first flag information is included in an extended header of the first packet.

3. In claim 2, A method wherein the above first flag information has a value of 1.

4. In claim 1, A method wherein the information about the at least one channel includes information indicating an interval between the at least one channel and information indicating a last channel through which the at least one second packet is transmitted among the at least one channel.

5. In claim 4, A method wherein the information indicating the last channel through which at least one second packet is transmitted includes a channel index of the last channel.

6. In claim 4, A method wherein the starting channel through which at least one second packet is transmitted is determined as the channel selected for the second sub-event.

7. In claim 1, A method wherein the second packet includes a preamble and a control header without a PDU (protocol data unit) header and a payload.

8. In claim 1, A method wherein the third packet is received after an inter frame space (IFS) from the end of transmission of the last packet among the at least one second packet.

9. In claim 1, A method wherein the third packet further includes second flag information indicating that channel information for the at least one channel is included in the third packet.

10. In claim 9, A method wherein the second flag information is included in the extended header of the third packet.

11. In claim 9, A method wherein the channel information for at least one channel includes information indicating channel quality for the channel through which the second packet is transmitted.

12. In claim 9, A method according to claim 1, wherein the third packet further includes information indicating a start channel through which the at least one second packet is transmitted among the at least one channel, information indicating an interval between the at least one channel, and information indicating a last channel through which the at least one second packet is transmitted.

13. A device configured to operate in a wireless communication system, said device comprising: transceiver; and At least one processor connected to the transceiver, At least one processor, Transmitting a first packet in a first sub-event within an event, wherein the first packet includes first flag information indicating that the first packet includes information about at least one channel through which at least one second packet is transmitted, and information about at least one channel through which the at least one second packet is transmitted. In a second sub-event within the above event, transmitting at least one second packet on at least one channel, and A device configured to receive a third packet including channel information for at least one channel in a second sub-event within the event.

14. As a computer-readable, non-transitory storage medium, A computer program configured to cause the device to perform an action when executed on the device, the action comprising: Transmitting a first packet in a first sub-event within an event, the first packet including first flag information indicating that information about at least one channel through which at least one second packet is transmitted is included in the first packet and information about at least one channel through which the at least one second packet is transmitted; transmitting at least one second packet on at least one channel in a second sub-event within said event, and A computer-readable non-transitory storage medium comprising receiving a third packet comprising channel information for at least one channel in a second sub-event within the event.

Images