Wireless communication device and method

Abstract

The present invention pertains to a wireless communication device and a method whereby wireless LAN system communications can be reliably performed even in an environment in which there are other wireless communication systems with different signaling schemes. The wireless communication device: detects a frequency hopping signal from a frequency hopping communication system which is operated periodically; from a signal detection timing at which the frequency hopping signal has been detected, predicts a first interference timing at which interference occurs with the frequency hopping signal; and transmits a frame while avoiding the first interference timing. The present invention can be applied to wireless communication systems.

Description

Technical Field

[0001] The present technology relates to a wireless communication device and method, and particularly to a wireless communication device and method that can reliably perform communication of a wireless LAN (Local Area Network) system even in an environment where other wireless communication systems with different signal formats exist.

Background Art

[0002] Wireless LAN systems can easily provide high-speed and high-capacity communication and use an internationally recognized frequency band, so they are widely used worldwide today.

[0003] On the other hand, as a wireless communication system using the same frequency band as the wireless LAN system, there is a FH communication system that uses frequency hopping (FH) technology such as Bluetooth (registered trademark) LE (Low Energy).

[0004] Since these two wireless communication systems use the same 2.4 GHz band called the ISM band, it is necessary to construct a mechanism for both wireless communication systems to coexist by removing interference between different wireless communication systems in the same frequency band.

[0005] Therefore, in the IEEE802 technical committee, technical studies for the coexistence of both wireless communication systems have been conducted. The Bluetooth technology is defined in the IEEE standard 802.15.1, and the coexisting IEEE standard 802.15.2 has been formulated. That is, in this IEEE standard 802.15.2, a technology for limiting the channels for FH when detecting other wireless communication systems such as a wireless LAN system is defined.

[0006] Currently, in wireless LAN systems, it has become possible to newly use the frequency band of the 6 GHz band, and for the time being, concerns about the depletion of frequency resources are being dispelled.

[0007] However, there are also movements to utilize the 6GHz frequency band in other wireless communication systems. For example, Bluetooth is exploring the use of these frequency bands.

[0008] In FH communication systems such as Bluetooth LE, transmission continues even if a Wi-Fi signal is detected, because communication is performed by switching frequencies. Therefore, while this FH communication system increases the probability of successful FH communication, it also increases the probability of Wi-Fi communication failure.

[0009] In particular, in FH communication systems, narrowband signals are transmitted intermittently, making it difficult to detect the use of a transmission path by observing the carrier wave, as is done in wireless LAN systems.

[0010] As mentioned above, the IEEE 802.15.2 standard was standardized to prevent interference, but Bluetooth only operates under this standard if a wireless LAN system is already present. Therefore, this standard is only practically used when the wireless LAN system is continuously transmitting data. In other words, when the wireless LAN system starts transmitting data, Bluetooth transmits a signal that interferes with the data transmission.

[0011] Bluetooth, through its Low Energy standard, has been enhanced with improved resilience by changing the signal format and placing the advertisement channel in the gaps of the channels used by wireless LAN systems. However, since the data channel is transmitted at the same frequency as wireless LAN systems, interference with wireless LAN systems remains unresolved.

[0012] Furthermore, the presence of other wireless communication systems in newly utilized frequency bands can prevent the originally anticipated throughput from being achieved. In other words, even if fair access control is implemented within the wireless LAN system to distribute usage, interference from signals from other wireless communication systems may prevent communication within the wireless LAN system from occurring at all.

[0013] Therefore, currently, the only way to effectively coexist with FH communication systems is to add a circuit to a later-entered wireless LAN system that determines whether or not an existing FH communication system is operating, and to use a frequency channel that avoids interference (see Patent Document 1). [Prior art documents] [Patent Documents]

[0014] [Patent Document 1] International Publication No. 2020 / 201679 [Overview of the Initiative] [Problems that the invention aims to solve]

[0015] Therefore, there is an urgent need for a method that can reliably perform wireless LAN system communication in an environment where other wireless communication systems exist that use the same frequency band as the wireless LAN system but have different signal formats.

[0016] This technology was developed in light of these circumstances, and utilizes the same frequency band as the wireless LAN system to ensure reliable communication of the wireless LAN system even in environments where other wireless communication systems with different signal formats exist. [Means for solving the problem]

[0017] One aspect of this technology is a wireless communication device comprising: a detection unit that detects a frequency-hopping signal from a periodically operating frequency-hopping communication system; a communication control unit that predicts a first interference timing that is periodically affected from the signal detection timing at which the frequency-hopping signal is detected; and a transmission unit that transmits a frame while avoiding the first interference timing.

[0018] Another aspect of this technology is a wireless communication device comprising: a receiving unit that receives a first frame containing information regarding coexistence with frequency-hopping signals detected from a periodically operating frequency-hopping communication system; and a communication control unit that, based on the coexistence information, causes the device to transmit a second frame while avoiding a first interference timing in which it would be interfered with by the frequency-hopping signals.

[0019] In one aspect of this technology, a frequency-hopping signal is detected from a periodically operating frequency-hopping communication system, and a first interference timing, during which periodic interference occurs, is predicted from the signal detection timing at which the frequency-hopping signal is detected. Then, a frame is transmitted while avoiding the first interference timing.

[0020] In another aspect of this technology, a first frame is received that contains information regarding coexistence with frequency-hopping signals detected from a periodically operating frequency-hopping communication system, and a second frame is transmitted based on the coexistence information, avoiding a first interference timing in which it would be interfered with by the frequency-hopping signals. [Brief explanation of the drawing]

[0021] [Figure 1] This figure shows an example configuration of a wireless LAN system according to one embodiment of this technology. [Figure 2] This figure shows an example of frequency bands and channel allocations used in wireless LAN systems. [Figure 3] This diagram shows the operating frequency channels of the FH communication system. [Figure 4]It is a diagram showing the usage form of channels in an FH communication system. [Figure 5] It is a block diagram showing a configuration example of a wireless communication device. [Figure 6] It is a block diagram showing a configuration example of the wireless communication module in FIG. 5. [Figure 7] It is a diagram showing the communication sequence of the wireless LAN system in FIG. 1. [Figure 8] It is a diagram showing a first configuration example of a data frame. [Figure 9] It is a diagram showing a second configuration example of a data frame. [Figure 10] It is a diagram showing a third configuration example of a data frame. [Figure 11] It is a diagram showing a first configuration example of a frame in which a silent period is set. [Figure 12] It is a diagram showing a second configuration example of a frame in which a silent period is set. [Figure 13] It is a diagram showing a third configuration example of a frame in which a silent period is set. [Figure 14] It is a diagram showing a configuration example of a block ACK frame. [Figure 15] It is a diagram showing a configuration example of a frame for notifying information regarding coexistence. [Figure 16] It is a diagram showing an example of parameter information managed by a wireless communication device. [Figure 17] It is a flowchart for explaining the data transmission process of a wireless communication device on the transmission side. [Figure 18] It is a flowchart for explaining the ACK reception process of a wireless communication device on the transmission side. [Figure 19] It is a flowchart for explaining the data reception process of a wireless communication device on the reception side. [Figure 20] It is a flowchart for explaining the detection process of an FH signal. [Figure 21] It is a block diagram showing a configuration example of a computer.

Embodiments for Carrying Out the Invention

[0022] The following describes the configurations for implementing this technology. The explanation will proceed in the following order. 1. Wireless LAN system 2. Configuration of the wireless communication device 3. Operation of the wireless LAN system 4. Frame Configuration 5. Operation of the wireless communication device 6. Others

[0023] <<1. Wireless LAN System>> <Wireless LAN System Configuration> Figure 1 shows an example configuration of a wireless LAN system, which is a wireless communication system according to one embodiment of this technology.

[0024] The wireless LAN system in Figure 1 consists of wireless communication devices 11-1 and 11-2. Wireless communication devices 11-1 and 11-2 are composed of smartphones, mobile phones, mobile terminals, and personal computers, etc. In the following, unless otherwise specified, wireless communication devices 11-1 and 11-2 will be referred to as wireless communication device 11.

[0025] The wireless communication device 11-1 transmits data to the wireless communication device 11-2 and receives ACK (Acknowledgement) information, which is an acknowledgment of receipt of the data, transmitted from the wireless communication device 11-2.

[0026] The wireless communication device 11-2 receives data transmitted from the wireless communication device 11-1 and sends ACK information to the wireless communication device 11-1.

[0027] In Figure 1, a frequency hopping (FH) communication system coexists in the vicinity of a wireless LAN system.

[0028] The FH system consists of FH communication devices 12-1 to 12-4. FH communication devices 12-1 to 12-4 are composed of devices that perform FH communication, such as smartphones, mobile phones, mobile terminals, personal computers, mice, headphones, earphones, and speakers. In the following, unless otherwise necessary, FH communication devices 12-1 to 12-4 will be referred to as FH communication device 12.

[0029] In Figure 1, when data is transmitted from wireless communication device 11-1 to wireless communication device 11-2, FH communication device 12-1 is located near wireless communication device 11-1, and FH communication device 12-2 is located near wireless communication device 11-2.

[0030] Meanwhile, FH communication device 12-1 transmits data to its paired FH communication device 12-3 using the FH method. FH communication device 12-2 transmits data to its paired FH communication device 12-4 using the FH method.

[0031] Because these FH signals have reduced transmission power, they are generally used for short-range communication.

[0032] In Figure 1, the ellipses centered on the marks representing wireless communication device 11-1, wireless communication device 11-2, FH communication device 12-1, and FH communication device 12-2 represent the transmission range of the radio waves transmitted by each of these devices. Therefore, the intersection of these ellipses schematically illustrates that simultaneous operation of each communication device would cause interference between them.

[0033] Furthermore, the dashed arrow from FH communication device 12-1 to wireless communication device 11-1 indicates that the signal transmitted from FH communication device 12-1 reaches wireless communication device 11-1. Similarly, the dashed arrow from FH communication device 12-2 to wireless communication device 11-2 indicates that the signal transmitted from FH communication device 12-2 reaches wireless communication device 11-2.

[0034] On the other hand, in cases where data transmission is performed continuously across a predetermined frequency band, such as in a wireless LAN system, these signals may become noise and reach the FH communication device 12.

[0035] In other words, the dashed arrow from the wireless communication device 11-1 to the FH communication device 12-1 indicates that the data transmitted from the wireless communication device 11-1 reaches the wireless communication device 12-1. Similarly, the dashed arrow from the wireless communication device 11-2 to the FH communication device 12-2 indicates that the ACK information transmitted from the wireless communication device 11-2 reaches the FH communication device 12-2.

[0036] Therefore, in the case of Figure 1, the data transmitted from wireless communication device 11-1 interferes with the communication of FH communication device 12-1, and the ACK information transmitted from wireless communication device 11-2 interferes with the communication of FH communication device 12-2.

[0037] Therefore, in the wireless LAN system of this technology, the wireless communication device 11-1 calculates the timing at which the FH communication device 12-1 transmits a signal and controls the transmission of data so as not to interfere with the signal transmitted by the FH communication device 12-1. Similarly, the wireless communication device 11-2 calculates the timing at which the FH communication device 12-2 transmits a signal and controls the transmission of ACK information so as not to interfere with the signal transmitted by the FH communication device 12-2.

[0038] By doing so, it is possible to reliably perform wireless LAN system communication even in environments where other wireless communication systems using the same frequency band but with different signal formats, such as the FH method, exist.

[0039] The following provides further details about this technology.

[0040] <Wireless LAN system frequency band and channel allocation> Figure 2 shows an example of frequency bands and channel allocation used in a wireless LAN system.

[0041] Figure 2 shows the available frequency bands and their channel allocation status for the wireless LAN system.

[0042] First, when applying the 2.4GHz band to a 20MHz bandwidth OFDM (Orthogonal Frequency Division Multiplexing) wireless signal according to the IEEE 802.11g standard, it is possible to set up at least three frequency channels in the 2.4GHz band.

[0043] Furthermore, in the 5GHz band, multiple channels can be reserved for 20MHz bandwidth OFDM wireless signals due to standards such as IEEE802.11a.

[0044] However, operation in the 5GHz band is subject to various national laws and regulations that specify the usable frequency range, transmission power, and conditions for determining whether transmission is permitted.

[0045] In Figure 2, channel numbers are indicated below the 5GHz band. In Japan, it is possible to use 8 channels from channel 36 to channel 64 and 11 channels from channel 100 to channel 140.

[0046] In other countries and regions, channels 32, 68, 96, and 144 are also available, and in the higher frequency bands, channels 149 through 173 are also available.

[0047] Regarding the use of the 6GHz band, which is currently being standardized to enable its use, as shown in Figure 2, it is possible to deploy 25 channels in the UNII-5 band of 6GHz band A, 5 channels in the UNII-6 band of 6GHz band B, 17 channels in the UNII-7 band of 6GHz band C, and 12 channels in the UNII-8 band of 6GHz band D.

[0048] In these frequency bands, by using a plurality of 20 MHz bandwidths, for example, two bands can be combined to continuously utilize a 40 MHz bandwidth, four bands can be combined to continuously utilize an 80 MHz bandwidth, and eight bands can be combined to continuously utilize a 160 MHz bandwidth.

[0049] <FH Communication System Operating Frequency Channels> Figure 3 is a diagram showing the operating frequency channels of the FH communication system.

[0050] On the left side of Figure 3, 40 channels for communication in the FH mode are prepared using all of the 2.4 GHz band.

[0051] Figure 3 shows RF (RF0 to RF39) representing the channel numbers and the frequencies (2402 MHz to 2480 MHz) corresponding to each RF.

[0052] In this FH communication system, 3 out of the 40 channels (for example, RF37 to RF39) are set as advertising channels, and control information other than data communication is exchanged.

[0053] Note that in the FH communication system, signals are not continuously transmitted at all times like in a wireless LAN system in these channels. Instead, as will be described later with reference to Figure 4, it is configured to operate by switching frequency channels using only one channel for a short time.

[0054] From this, a mechanism for coexistence in both the wireless LAN system and the FH communication system has been standardized in IEEE802.15.2, and a part of it is defined as Adaptive Frequency Hopping (AFH).

[0055] This AFH is to set channels to be used for frequency hopping while avoiding frequency channels that are already being used in a wireless LAN system or the like in advance.

[0056] On the right side of FIG. 3, it shows how the FH communication system uses frequency channels not used by the wireless LAN system by means of AFH.

[0057] On the right side of FIG. 3, Wi-Fi ch1 (RF0 to RF8), Wi-Fi ch6 (RF11 to RF20), and Wi-Fi ch11 (RF24 to RF32) compliant with the IEEE802.11b standard are shown as the frequency channels used by the wireless LAN system.

[0058] Therefore, the FH communication system uses 12 channels of RF9, RF10, RF21 to RF23, and RF33 to RF36 among the 40 channels, in addition to RF37 to RF39 set as the advertise channels.

[0059] As described above, AFH is a mechanism when the frequency channels used by the wireless LAN system are known.

[0060] Therefore, when there is no communication by the wireless LAN system and only communication by the FH communication system is performed, the FH communication system communicates using 40 channels as shown on the left side of FIG. 3.

[0061] <Channel utilization pattern in the FH communication system> FIG. 4 is a diagram showing the channel utilization pattern in the FH communication system.

[0062] In FIG. 4, the vertical axis represents the frequency channel, and the horizontal axis represents the passage of time. For the convenience of explanation, 8 channels are shown as the frequency resource units (RU), but in reality, frequency shift is performed for each of the 40 channels and transmission is carried out.

[0063] In other words, at any given timing, an FH signal is transmitted at frequency f5, at the next timing, an FH signal is transmitted at frequency f6, and at the following timing, an FH signal is transmitted at frequency f7.

[0064] Then, after the FH signal is transmitted at frequency f8, the FH signal is transmitted at frequency f1.

[0065] Due to this frequency shift, when the lowest frequency f1 in the frequency band is used as the reference, the timing from the start of FH signal detection to the detection of an FH signal at frequency f1 is defined as the offset, the period until it returns to frequency f1 is defined as the interval, and the time during which the FH signal continues to be detected is defined as the duration.

[0066] Furthermore, as a frequency parameter, the bandwidth over which resource units (RUs) continuously frequency-hop is set to the frequency range required to detect the FH signal.

[0067] In the wireless communication device 11 of this wireless LAN system, FH signal detection is performed based on these parameters.

[0068] <<2. Configuration of Wireless Communication Device>> <Configuration of wireless communication equipment> Figure 5 is a block diagram showing an example configuration of the wireless communication device 11.

[0069] The wireless communication device 11 in Figure 5 consists of an internet connection module 51, an information input module 52, an equipment control module 53, an information output module 54, and a wireless communication module 55.

[0070] Furthermore, the wireless communication device may consist only of the necessary modules.

[0071] When the Internet connection module 51 operates as an access point device under the control of the device control module 53, it is configured to implement functions such as a communication modem for connecting to the Internet network. The Internet connection module 51 establishes a connection to the Internet via a public communication line and an Internet service provider.

[0072] The information input module 52 outputs information that conveys instructions entered by the user to the device control module 53. The information input module 52 consists of push buttons, a keyboard, a touch panel, etc.

[0073] The device control module 53 consists of a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), and other components. The device control module 53 executes programs stored in the ROM and other components, enables applications to function at higher layers, and controls the device to operate as a wireless communication device or access point.

[0074] The information output module 54 outputs information regarding the operating status of the wireless communication device 11, supplied by the device control module 53, or information obtained via the Internet. The information output module 54 consists of display elements such as LEDs, liquid crystal panels, or organic displays, or speakers that output sound or music. The information output module 54 displays or notifies the user of necessary information.

[0075] The wireless communication module 55 transmits data supplied from the equipment control module 53 to the other wireless communication device 11 by performing wireless communication. The wireless communication module 55 receives data transmitted from the other wireless communication device 11 by performing wireless communication and outputs the received data to the equipment control module 53.

[0076] <Configuration of the wireless communication module> Figure 6 is a block diagram showing an example configuration of the wireless communication module 55.

[0077] The wireless communication module 55 consists of an interface 101, a transmit buffer 102, a frame construction unit 103, a communication control unit 104, a signal transmission processing unit 105, and an FH signal detection unit 106. The wireless communication module 55 also consists of a high-frequency processing unit 107, antennas 108-1 and 108-2, a signal reception processing unit 109, a frame analysis unit 110, and a receive buffer 111.

[0078] Interface 101 functions as an interface for exchanging information input from the user via the device control module 53 and data supplied from the Internet network in a predetermined signal format.

[0079] Interface 101 outputs information and data supplied from the device control module 53 to the transmit buffer 102 and the communication control unit 104. Interface 101 also outputs information and data supplied from the receive buffer 111 to the device control module 53.

[0080] The transmit buffer 102 temporarily stores information input from the user and signals for wireless communication when it receives such signals.

[0081] The frame construction unit 103 constructs data (MAC layer protocol data unit (MPDU) frames or A-MPDU (aggregated MPDU)) frames and ACK frames using data stored in the transmission buffer 102 and ACK information supplied from the communication control unit 104, in accordance with instructions from the communication control unit 104. The frame construction unit 103 outputs the constructed frames to the signal transmission processing unit 105.

[0082] The communication control unit 104 manages operations for sending and receiving data and ACK information based on information supplied from the interface 101 and the frame analysis unit 110. The communication control unit 104 grasps the frame construction and data transmission / reception status and controls the frame construction unit 103, the signal transmission processing unit 105, the FH signal detection unit 106, and the signal reception processing unit 109.

[0083] Furthermore, the communication control unit 104 calculates the interference timing at which it receives interference from the FH communication system based on the information supplied by the FH signal detection unit 106, and stores its periodic movement in its built-in memory. The communication control unit 104 instructs the frame construction unit 103 to construct the A-MPDU frames and ACK frames of the wireless LAN system so as not to interfere with the FH communication system, and transmits them via the signal transmission processing unit 105. Note that the interference timing may be the timing at which it receives interference from the FH communication system, but it may also be the timing at which it causes interference by transmitting its own signals. Therefore, it will also be referred to below as the timing at which it interferes with the FH signal.

[0084] The signal transmission processing unit 105 performs encoding processing on the data to be transmitted and outputs the encoded data to the high-frequency processing unit 107.

[0085] The FH signal detection unit 106 detects signals from the FH communication system. Specifically, in order to coexist with the FH communication system, the FH signal detection unit 106 detects FH signals transmitted from surrounding FH communication systems and outputs information such as the signal detection timing, frequency band, and received field strength to the communication control unit 104.

[0086] The high-frequency processing unit 107 applies predetermined high-frequency processing to the data supplied from the signal transmission processing unit 105 and constructs signals for each of the multiple frequency bands. The high-frequency processing unit 107 transmits the constructed signals to the wireless communication device 11 of the communication partner via antennas 108-1 and 108-2.

[0087] Furthermore, the high-frequency processing unit 107 receives signals in each frequency band transmitted from the wireless communication device 11 of the communication partner via antennas 108-1 and 108-2, and outputs the received signals to the signal receiving processing unit 109.

[0088] The signal receiving processing unit 109 processes the signal supplied from the high-frequency processing unit 107 and outputs it to the frame analysis unit 110.

[0089] The frame analysis unit 110 extracts predetermined data frames from the received data, and extracts various information and data such as header information, delimiters, and payloads from the ACK frame. The frame analysis unit 110 outputs the extracted information to the communication control unit 104 and outputs the extracted data to the receive buffer 111.

[0090] The receive buffer 111 stores the data supplied from the frame analysis unit 110.

[0091] <<3. Operation of the Wireless LAN System>> <Communication sequence of a wireless LAN system> Figure 7 shows the communication sequence of the wireless LAN system in Figure 1.

[0092] In Figure 7, wireless communication device 11-1 is the transmitting wireless communication device. Wireless communication device 11-2 is the receiving wireless communication device. As described above in Figure 1, FH communication devices 12-1 and 12-2 are located around wireless communication devices 11-1 and 11-2, respectively.

[0093] Figure 7 shows an example in which the transmission of data (MPDU#1~#8) from wireless communication device 11-1 to wireless communication device 11-2 begins when FH communication devices 12-1 and 12-2 are already operational.

[0094] In Figure 7, the exchange of information is shown downwards in the figure, illustrating how each device operates over time. The dashed arrows in the figure indicate that FH signals are intermittently transmitted from FH communication devices 12-1 and 12-2, and that the FH signals are interfering with the wireless communication devices 11-1 and 11-2, respectively.

[0095] First, when the wireless communication device 11-1 transmits data (MPDU#1~#8), in step S1, it observes the parameters of the FH signal that is being interfered with by the surrounding FH communication device 12-1, and observes information on the period and duration of the detected FH signal in the frequency band used for transmitting data for a predetermined period of time.

[0096] Here, the specified time can be, for example, a time equal to or greater than the period of the FH signal specified in the standards of an existing FH communication system.

[0097] As a result, the wireless communication device 11-1 can calculate the parameters of the periodic FH signals of the FH communication devices 12-1 in its vicinity, as shown in Figure 4, and can therefore estimate the interference timing in which it interferes with the FH signals in the frequency band used for data transmission.

[0098] Then, in step S2, the wireless communication device 11-1 transmits data (MPDU#1~#8). At that time, the wireless communication device 11-1 constructs the data as an A-MPDU frame and determines that if the estimated interference timing falls on the boundary or padding of the MPDU, the possibility of interference is low, and if it falls in the middle of the MPDU (for example, the payload portion), it determines that there is a possibility of interference.

[0099] If the payload portions of MPDU#5 and MPDU#7 of the A-MPDU fall within the interference timing, the wireless communication device 11-1 transmits them with a timing shift, as indicated by arrows P1 and P2, to avoid interference with the FH signal. For example, the frame of the A-MPDU is transmitted with a timing shift so that the interference timing falls within the boundary or padding of that MPDU.

[0100] On the other hand, in step S3, the wireless communication device 11-2 receives a data (A-MPDU) frame addressed to itself. When the wireless communication device 11-2 receives a data (A-MPDU) frame addressed to itself, it may periodically interfere with the FH signal transmitted from the FH communication device 12-2, as shown by the dashed line in the figure.

[0101] Figure 7 shows a case where interference timing from the signal from FH communication device 12-2 overlaps with the reception of the payload portions of MPDU#4, MPDU#6, and MPDU#8, resulting in incorrect reception of this data. Specifically, a reception error occurs where the solid arrow from wireless communication device 11-1 and the dashed arrow from FH communication device 12-2 overlap.

[0102] Then, after receiving the predetermined data A-MPDU, the wireless communication device 11-2 sends an ACK frame to the wireless communication device 11-1 in step S4.

[0103] Since this ACK frame may not be received correctly if it is sent to the wireless communication device 11-1 at an interference timing that interferes with the FH signal from the FH communication device 12-1, the wireless communication device 11-2 controls the transmission to avoid these interference timings.

[0104] The interference timing information described above may be included in the data frame header or delimiter, especially if there is undelivered data, as information regarding coexistence with the FH communication device 12-1. In this case, the wireless communication device 11-2 constructs an ACK frame and performs transmission control by referring to the parameter information included in the data frame header or delimiter.

[0105] The ACK frame contains ACK information, which lists the data that was received (#1, #2, #3, #5, #7), and indicates that there is undelivered data (#4, #6, #8).

[0106] Furthermore, this ACK frame may also contain information regarding coexistence with the communication of the FH communication device 12-2 in the wireless communication device 11-2.

[0107] In this case, the wireless communication device 11-1 can retransmit the data by constructing a frame (A-MPDU) of retransmitted data, avoiding the interference timing at which the wireless communication device 11-2 interferes with the FH signal.

[0108] Then, in step S7, the wireless communication device 11-2 receives the data that is retransmitted at a timing that does not interfere with the FH signals from the FH communication devices 12-1 and 12-2.

[0109] Finally, when all the data is received, the wireless communication device 11-2 sends back an ACK frame in step S8 indicating that all the data is received.

[0110] In step S9, the wireless communication device 11-1 receives an ACK frame transmitted from the wireless communication device 11-2. After this, the communication sequence shown in Figure 7 ends.

[0111] <<4. Frame Configuration>> <Example of the first data frame structure> Figure 8 shows a first example of the data frame configuration of this technology.

[0112] The data frame shown in Figure 8 consists of an A-MPDU frame, which is formed by concatenating a predetermined preamble "H" and MPDUs #1 through #8.

[0113] In Figure 8, FH1, shown next to the data frame, represents the FH signal (hereinafter referred to as the FH1 signal) transmitted by the FH communication device 12-1. The same applies to subsequent figures.

[0114] The preamble "H" consists of the following as a predetermined PLCP (Physical Layer Convergence Protocol) header: "L-STF", "L-LTF", "L-SIG", "RL-SIG", "U-SIG", "EHT-SIG", "EHT-STF", and "EHT-LTF".

[0115] "L-STF" is the conventional short training field. "L-LTF" is the conventional long training field. "L-SIG" is the conventional signal information, and "RL-SIG" is a repetition of the L-SIG information.

[0116] "U-SIG" is signal information updated with each specified version. "EHT (Extremely High Throughput)-SIG" is signal information for the current latest version (hereinafter referred to as the EHT version). "EHT-STF" is a short training field in the EHT version. "EHT-LTF" is a long training field in the EHT version.

[0117] The "EHT-SIG" includes the "COEX Enable" bit. The "COEX Enable" bit is coexistence information used to identify whether or not coexistence operation with the FH communication system is possible.

[0118] An A-MPDU frame contains MPDUs #1 through #8, a portion "P" which is sent as padding at the MPDU boundaries, and a silent period "S". The A-MPDU frame is constructed such that if there is a possibility of interference with the FH1 signal during transmission of this frame, "P" or "S" is placed at the location where interference is expected.

[0119] In other words, the wireless communication device 11-1 predicts in advance the interference timing when it will interfere with the periodically transmitted FH1 signal based on the signal detection status of the surrounding FH communication device 12-1, and arranges the MPDUs so that padding "P" arrives between MPDU#2 and MPDU#3 to match the interference timing from the frame start timing, thereby fine-tuning the frame start timing and constructing an A-MPDU frame. In these padding operations, the device may configure the device to actually fill the data with predetermined bits, or it may configure the device to transmit while suppressing the transmission power.

[0120] Furthermore, if interference timing of the FH1 signal is predicted during MPDU#5, the wireless communication device 11-1 pre-inserts a silent period "S" between MPDU#4 and MPDU#5 until the interference timing is over, so as not to interfere with the FH1 signal when transmitting MPDU#5.

[0121] Furthermore, if interference timing of the FH1 signal is predicted during MPDU#7, the wireless communication device 11-1 pre-inserts a silent period "S" between MPDU#7 and MPDU#8 until the interference timing is over, so as not to interfere with the FH1 signal when transmitting MPDU#7.

[0122] <Second example of data frame structure> Figure 9 shows a second example of the data frame configuration of this technology.

[0123] Figure 9 shows an example of a retransmitted data frame (hereinafter also referred to as a retransmitted frame) constructed based on coexistence information transmitted from the receiving wireless communication device 11-2.

[0124] In Figure 9, FH1 shown next to the data frame represents the FH1 signal transmitted by FH communication device 12-1, and FH2 shown next to the data frame represents the signal transmitted by FH communication device 12-2 (hereinafter referred to as the FH2 signal). The same applies to subsequent figures.

[0125] The retransmitted frames in Figure 9 are frames that retransmit MPDU#4, MPDU#6, and MPDU#8. The retransmitted frames are configured to avoid interference not only with the FH1 signal from the FH communication device 12-1 surrounding the transmitting radio communication device 11-1, but also with the FH2 signal from the FH communication device 12-2 surrounding the receiving radio communication device 11-2.

[0126] In other words, the wireless communication device 11-1 sets a silent period "S" after MPDU#4 to prevent interference with the FH2 signal when the wireless communication device 11-2 receives it, and the padding "P" of MPDU#6 fine-tunes the frame start timing and constructs a retransmission frame to prevent interference with the FH1 signal when it transmits it.

[0127] <Third example of data frame structure> Figure 10 shows a third example of the data frame configuration of this technology.

[0128] Figure 10 shows an example of a data frame with a delimiter indicating the boundary of the A-MPDU frame and padding added to the MPDU payload.

[0129] The delimiter consists of the EOF, Length, COEX, and CRC fields. In other words, in Figure 10, the delimiter has an additional "COEX" field to identify that it is a frame configuration coexisting with the FH signal.

[0130] The MPDU payload consists of a frame body and a frame check sequence (FCS) for error detection, attached to a predetermined MAC header.

[0131] The MAC header consists of fields such as Frame Control, Duration, Address1 through Address3 (address fields), Sequence Control, Address4, QoS Control, and EHT Control.

[0132] Frame Control contains information used for frame control and other related tasks.

[0133] Duration contains information indicating the duration of the frame.

[0134] The address field contains address information.

[0135] Sequence Control includes the sequence number, etc.

[0136] QoS Control includes QoS parameters, etc.

[0137] EHT Control includes parameters that are controlled in the EHT version.

[0138] In Figure 10, the padding period is shown to include the timing of interference with the FH signal. By appropriately placing this padding within the frame, the A-MPDU data frame, which consists of consecutive MPDUs, can coexist with the surrounding FH signal.

[0139] <Example of a first configuration for a frame in which a silent period is set> Figure 11 shows a first example configuration of a frame in which a silent period is set.

[0140] In Figure 11, instead of the MPDU that constitutes the A-MPDU described above, a delimiter indicating the formation of a silent period is added, and an example of a frame in which a silent period is set over the length specified in the "Length" of this delimiter is shown.

[0141] Furthermore, this frame may be configured to transmit a "COEX Info" field outside the delimiter, if necessary, which contains information about coexistence.

[0142] In Figure 11, the "COEX Info" field contains COEX information, specifically the COEX time domain information, including parameters related to coexistence such as offset information, duration information, and interval information.

[0143] Furthermore, in the wireless communication device 11-1, in order to actually coexist with the FH signal, during the silent period that includes the interference timing of the FH signal (i.e., until the next delimiter), control is performed to either temporarily suspend the transmission of the signal or reduce the transmission power.

[0144] The "COEX Info" field may also contain other parameters related to coexistence, such as those shown in Figure 11, from the COEX information.

[0145] <Second example of a frame configuration in which a silent period is set> Figure 12 shows a second example of a frame configuration in which a silent period is set.

[0146] Figure 12 shows an example of a frame in which a silent period is set over the period during which multiple FH signals are received, in order to avoid interference between the FH1 signal detected by the transmitting wireless communication device 11-1 and the FH2 signal detected by the receiving wireless communication device 11-2.

[0147] In other words, the "Length" setting for the delimiter in Figure 12 is set to the length of the silent period, taking into account the period during which multiple FH signals are received.

[0148] Thus, when there are interference timings for multiple FH signals that are close in time, instead of setting silent periods for each signal individually, a single silent period may be set to avoid interference with the FH1 and FH2 signals, and to allow coexistence with the FH communication devices 12-1 and 12-2.

[0149] Furthermore, the "COEX" field of the delimiter in Figure 12 contains the coexistence-related parameters such as Offset, Duration, and Interval, which were listed as COEX time domain information in the COEX Info section of Figure 11.

[0150] In other words, as long as the specified size within the delimiter is not exceeded, parameters related to coexistence may be described in the "COEX" field of the delimiter, for example, as shown in Figure 12.

[0151] <Third example of a frame configuration in which a silent period is set> Figure 13 shows a third example of a frame configuration in which a silent period is set.

[0152] Figure 13 shows an example of a frame that notifies of a silent period by storing only the minimum necessary interval information, namely the Interval field, within the delimiter, without adding the COEX Info field for coexistence information within the frame.

[0153] In other words, since the receiving wireless communication device 11-2 only needs to detect the delimiter, the wireless communication device 11-1 stops transmitting or suppresses the transmission power for a period of Length (i.e., a silent period) after the delimiter.

[0154] <Example of a Block ACK frame configuration> Figure 14 shows an example of the configuration of a block ACK frame of this technology.

[0155] The block ACK frame shown in Figure 14 consists of a predetermined preamble "H", Frame Control, Duration, Receive Address, Transmit Address, BA Control, BA Information, COEX Info, and FCS fields.

[0156] Frame Control and Duration are the same as in Figure 10.

[0157] Duration includes information indicating the duration.

[0158] The Receive Address contains information that identifies the recipient.

[0159] The Transmit address contains information that identifies the sender.

[0160] BA Control includes control information such as the type of block ACK frame.

[0161] BA Information includes block ACK information.

[0162] COEX Info contains information about coexistence.

[0163] This COEX Info includes parameters such as the detection status of signals from surrounding FH communication devices 12.

[0164] For example, COEX Info includes subfields for coexistence as time domains: Offset, which indicates the timing from the start of detection until a signal of a predetermined frequency is detected; Duration, which indicates the time the signal continued to be detected as an FH signal; and Interval, which indicates the period until the same frequency is detected again.

[0165] Note that the COEX Info field may also contain other parameters related to coexistence (Other Parameter).

[0166] The FCS contains information for error detection.

[0167] As shown in Figure 14, by notifying wireless communication device 11-1 of COEX Info, which is information regarding coexistence, from wireless communication device 11-2 using a block ACK frame, wireless communication device 11-1 becomes able to calculate the timing at which both the transmitting and receiving sides do not interfere with the FH signal.

[0168] <Example of a frame structure for notifying information about coexistence> Figure 15 shows an example of the configuration of a frame that notifies information regarding the coexistence of this technology.

[0169] Figure 15 shows an example of a frame configuration in which these parameters are made up as information elements. This frame can be configured, for example, as part of an action frame, a management frame, or a control frame.

[0170] The frame in Figure 15 consists of a predetermined PLCP header "H", Frame Control, Duration, Frame Control, Duration, Receive Address, Transmit Address, COEX Info, and FCS.

[0171] In other words, the frame in Figure 15 is the same as in Figure 14, except that BA Control and BA Information have been removed.

[0172] <Parameter information managed by wireless communication devices> Figure 16 shows an example of parameter information managed by the wireless communication device 11.

[0173] This document describes various parameters that are exchanged between the communication control unit 104 and the FH signal detection unit 106 when the wireless communication device 11 is in operation.

[0174] The FH signal detection unit 106 outputs continuous detection period information and detection threshold information related to the period during which the FH signal is continuously detected to the communication control unit 104.

[0175] The FH signal detection unit 106 then starts a predetermined timer and, upon detecting an FH signal, acquires detection start time information, received field strength information, detection bandwidth information (information on the bandwidth of the detected frequency), and detection duration information (information on the duration of the detected signal). The FH signal detection unit 106 sequentially notifies the communication control unit 104 of these parameter information.

[0176] Furthermore, if multiple FH signals of the same frequency are detected by the FH signal detection unit 106 during the continuous detection period, the communication control unit 104 may sequentially add FH detection period information, which is information about the detection period, and notify the user. Alternatively, the communication control unit 104 may set these detection periods as a result of analysis and notify the user as FH setting period information.

[0177] When the communication control unit 104 receives parameter information detected by the FH signal detection unit 106, it stores it as interference offset information, interference bandwidth information, and interference duration information. The communication control unit 104 may also calculate the period of interference from this information and calculate interference period information.

[0178] In other words, the communication control unit 104 calculates information regarding coexistence with signals from surrounding FH communication devices 12 (interference bandwidth information, interference period information, interference offset information, interference duration information) from the parameter information detected by the FH signal detection unit 106.

[0179] Furthermore, the communication control unit 104 also stores information about the receiving device, such as the address information of the wireless communication device that will be the data communication partner, as well as information about communication parameters such as coding rate information and modulation scheme information used for communication with that communication device.

[0180] These parameters are merely some of the information necessary to explain this technology, and you may use only some of the parameters listed here, or you may use other parameters as appropriate.

[0181] <<5. Operation of Wireless Communication Devices>> <Data transmission process> Figure 17 is a flowchart illustrating the data transmission process of the transmitting wireless communication device 11-1.

[0182] In step S101, the communication control unit 104 waits until it determines that it is operating in a new frequency band. If it is determined in step S101 that it is operating in a new frequency band, the process proceeds to step S102.

[0183] In step S102, the FH signal detection unit 106 starts the signal detection process for the FH communication system. Details of this signal detection process will be described later with reference to Figure 20.

[0184] In step S103, the communication control unit 104 determines whether or not it has received data to be transmitted via the interface 101. If it is determined in step S103 that it has received data to be transmitted, the process proceeds to step S104.

[0185] In step S104, the communication control unit 104 stores the received data in the transmission buffer 102 in predetermined MPDU units.

[0186] If it is determined in step S103 that the data to be sent has not been received, step S104 is skipped and the process proceeds to step S105.

[0187] In step S105, the communication control unit 104 determines whether data transmission is possible after a predetermined waiting time for transmission backoff of access control has elapsed. If it is determined in step S105 that data transmission is not possible, the process returns to step S103, and the subsequent processes are repeated.

[0188] If it is determined in step S105 that data transmission is possible, the process proceeds to step S106. Note that, in this step, the subsequent frame construction process may be executed before the timing when data transmission becomes possible.

[0189] In step S106, the communication control unit 104 calculates the transmission timing, which is the timing at which data can be transmitted.

[0190] In step S107, the communication control unit 104 determines whether or not an FH signal has been detected in the surrounding area. If it is determined in step S107 that an FH signal has been detected in the surrounding area, the process proceeds to step S108.

[0191] In step S108, the communication control unit 104 acquires its own COEX information, which is information regarding coexistence with the FH signal.

[0192] In step S109, the communication control unit 104 controls the inclusion of COEX information in the frame header or the like.

[0193] If it is determined in step S107 that no FH signal was detected in the surrounding area, steps S108 and S109 are skipped, and the process proceeds to step S110.

[0194] In step S110, the communication control unit 104 predicts in advance the transmission timing for constructing and transmitting a predetermined A-MPDU frame, and acquires MPDU information. The communication control unit 104 calculates the transmission time based on the length of the MPDU information and the modulation scheme and coding rate parameters of the data to be transmitted.

[0195] In step S111, the communication control unit 104 determines whether there is a possibility of interference with the next arriving FH signal. If it is determined in step S111 that there is a possibility of interference, the process proceeds to step S112.

[0196] In step S112, the communication control unit 104 determines whether or not it is possible to fine-tune the timing of the MPDU. If it is determined in step S112 that it is possible to fine-tune the timing of the MPDU, the process proceeds to step S113.

[0197] In step S113, the communication control unit 104 controls the padding position at the end of the MPDU boundary position. The process then proceeds to step S115.

[0198] If it is determined in step S112 that fine-tuning of the MPDU timing is not possible, the process proceeds to step S114.

[0199] In step S114, the communication control unit 104 controls the system to insert a silent period that includes the interference timing of the next incoming FH signal. The process then proceeds to step S115.

[0200] Furthermore, if the interference timings of the FH signals occur consecutively with short periods, a silent period may be set that includes the interference timings of multiple FH signals.

[0201] If it is determined in step S111 that there is no possibility of interference, the process proceeds to step S115.

[0202] In other words, if there is no possibility of interference with the FH signal, or if the timing of the FH signal interference coincides with the padding position of the MPDU, and there is a possibility of natural coexistence, then the padding position adjustment or the insertion of a silent period control is not performed.

[0203] In step S115, the communication control unit 104 adds the MPDU and constructs an A-MPDU frame.

[0204] In step S116, the communication control unit 104 determines whether or not it is possible to add an MPDU to the A-MPDU frame. If it is determined in step S116 that it is possible to add an MPDU, the process returns to step S110, and the subsequent processes are repeated.

[0205] If it is determined in step S116 that the MPDU cannot be added, the process proceeds to step S117.

[0206] In step S117, the communication control unit 104 waits until the predetermined transmission time arrives. If it is determined in step S117 that the transmission time has arrived, the process proceeds to step S118.

[0207] In step S118, the communication control unit 104 causes the A-MPDU frame to be transmitted.

[0208] In step S119, the communication control unit 104 determines whether the transmission of all data to be transmitted has been completed. If it is determined in step S119 that the transmission of all data to be transmitted has not yet been completed, the process returns to step S103.

[0209] In step S119, when it is determined that the transmission of all data to be transmitted has ended, the data transmission process in FIG. 17 ends.

[0210] <ACK reception process> FIG. 18 is a flowchart for explaining the ACK reception process of the wireless communication device 11-1 on the transmission side.

[0211] The process in FIG. 18 is a process performed by the wireless communication device 11-1 on the transmission side after the data transmission in FIG. 17.

[0212] The communication control unit 104 of the wireless communication device 11-1 waits for an ACK from the wireless communication device 11-2, and in step S151, determines whether an ACK has been received from the wireless communication device 11-2. If it is determined in step S151 that an ACK has not been received from the wireless communication device 11-2, the process proceeds to step S152. [[ID=**15]]

[0213] In step S152, the communication control unit 104 transmits a Block ACK request to prompt the wireless communication device 11-2 to transmit a Block ACK frame. After that, the process returns to step S151, and the subsequent processes are repeated.

[0214] If it is determined in step S151 that an ACK has been received from the wireless communication device 11-2, the process proceeds to step S153. [[ID=**23]]

[0215] In step S153, the communication control unit 104 acquires the block ACK information included in the block ACK frame.

[0216] In step S154, the communication control unit 104 determines whether there is any outstanding data for which the reception of the already transmitted data has not been confirmed based on the block ACK information. If it is determined in step S154 that there is outstanding data, the process proceeds to step S155.

[0217] In step S155, the communication control unit 104 identifies the undelivered data and retrieves the undelivered MPDU from the transmission buffer 102.

[0218] In step S156, the communication control unit 104 determines whether or not a COEX information element related to coexistence is attached to the block ACK frame. If it is determined in step S156 that a COEX information element related to coexistence is attached to the block ACK frame, the process proceeds to step S157.

[0219] In step S157, the communication control unit 104 acquires interference information for the FH signal on the receiving side.

[0220] In step S158, the communication control unit 104 also acquires interference information for the FH signal on the transmitting side.

[0221] In step S159, the communication control unit 104 calculates and identifies the next interference timing that will interfere with the FH signal, based on interference information from both the receiving and transmitting sides.

[0222] In step S160, the communication control unit 104 determines whether there is a possibility that an interference timing that will interfere with the FH signal may be present in the MPDU to be retransmitted. If it is determined in step S160 that there is a possibility that an interference timing that will interfere with the FH signal may be present in the MPDU to be retransmitted, the process proceeds to step S161.

[0223] In step S161, the communication control unit 104 controls the system to insert a silent period that includes all interfering timings. The process then proceeds to step S162.

[0224] If it is determined in step S156 that the block ACK frame does not have a COEX information element related to coexistence attached, the process proceeds to step S162.

[0225] If, in step S160, it is determined that there is no possibility of interference timing occurring in the MPDU to be retransmitted that would next interfere with the FH signal, the process proceeds to step S162.

[0226] In step S162, the communication control unit 104 constructs an A-MPDU frame from the data to be retransmitted (MPDU) obtained from the transmission buffer 102 and performs retransmission.

[0227] In step S162, after sending the retransmitted frame, the process returns to step S151, and the subsequent processing is repeated. That is, the communication control unit 104 waits again for the reception of an ACK frame.

[0228] On the other hand, if it is determined in step S154 that there is no undelivered data, the ACK reception process ends.

[0229] <Data reception processing> Figure 19 is a flowchart illustrating the data reception process of the receiving wireless communication device 11-2.

[0230] In step S201, the communication control unit 104 of the wireless communication device 11-2 determines whether or not a predetermined PLCP header has been detected. If it is determined in step S201 that a predetermined PLCP header has been detected, the process proceeds to step S202.

[0231] In step S202, the communication control unit 104 starts the FH signal detection process. Details of this signal detection process will be described later with reference to Figure 20.

[0232] In step S203, the communication control unit 104 determines whether or not it has detected the configuration of a predetermined A-MPDU frame. If it is determined in step S203 that it has detected the configuration of a predetermined A-MPDU frame, the process proceeds to step S204.

[0233] In step S204, the communication control unit 104 analyzes the delimiter information from the A-MPDU frame.

[0234] In step S205, the communication control unit 104 acquires the Length information included in the delimiter information.

[0235] In step S206, the communication control unit 104 determines whether or not it is a silent period. If it is determined in step S206 that it is a silent period, the process proceeds to step S207.

[0236] In step S207, the communication control unit 104 sets the time specified in the Length information, and the process returns to step S203, and the subsequent processing is repeated. That is, the communication control unit 104 waits for the decoding process to begin until the time specified in the Length information is reached.

[0237] If, in step S206, it is determined that the data is not from a silent period, i.e., it is MPDU data, the process proceeds to step S208.

[0238] In step S208, the communication control unit 104 performs the decoding process of the MPDU.

[0239] In step S209, the communication control unit 104 determines whether the FCS for error detection is at a normal value. If it is determined in step S209 that the FCS for error detection is at a normal value, the process proceeds to step S210.

[0240] In step S210, the communication control unit 104 causes the data to be stored in the receive buffer 111.

[0241] In step S211, the communication control unit 104 constructs the sequence number of the data as ACK information. Then, the process returns to step S203, and the subsequent processing is repeated.

[0242] Furthermore, if the FCS for error detection is determined not to be a normal value in step S209, the data is treated as undelivered data, and the process returns to step S203, and the subsequent processing is repeated.

[0243] If it is determined in step S203 that the configuration of a predetermined A-MPDU frame has not been detected, for example, when the reception process for a series of A-MPDU frames is completed or when a block ACK request frame is received, the process proceeds to step S212.

[0244] In step S212, the communication control unit 104 determines whether or not an ACK (acknowledgment) is required. If it is determined in step S212 that an ACK is required, the process proceeds to step S213.

[0245] In step S213, the communication control unit 104 acquires ACK information.

[0246] In step S214, the communication control unit 104 determines whether or not an FH signal has been detected. If it is determined in step S214 that an FH signal has been detected, the process proceeds to step S215.

[0247] In step S215, the communication control unit 104 acquires COEX information regarding the coexistence of the receiving wireless communication device 11-2 and records it in a predetermined field.

[0248] If it is determined in step S214 that no FH signal has been detected, the process in step S215 is skipped, and the process proceeds to step S216.

[0249] In step S216, the communication control unit 104 constructs a block ACK frame based on the ACK information.

[0250] In step S217, the communication control unit 104 acquires COEX information regarding the coexistence of the transmitting wireless communication device 11-1.

[0251] In step S218, the communication control unit 104 waits until a timing when coexistence is possible. At this time, the COEX information regarding the coexistence of the wireless communication devices 11 on the transmission side and the reception side is referred to. If both exist, both are referred to, and if only one exists, only one is referred to. If it is determined in step S218 that the timing when coexistence is possible has arrived, the process proceeds to step S219.

[0252] In step S219, the communication control unit 104 transmits a block ACK frame.

[0253] In step S220, the communication control unit 104 determines whether there is any missing data. If it is determined in step S220 that there is no missing data, the data reception process of the wireless communication device 11-2 ends.

[0254] If it is determined in step S220 that there is missing data, the process returns to step S201, and the subsequent processes are repeated.

[0255] If it is determined in step S201 that a predetermined PLCP header has not been detected, or if it is determined in step S212 that an ACK return is not necessary, the process also returns to step S201, and the subsequent processes are repeated.

[0256] <FH Signal Detection Process> FIG. 20 is a flowchart for explaining the FH signal detection process started in step S102 of FIG. 17 and step S202 of FIG. 19.

[0257] In step S251, the FH signal detection unit 106 determines whether an FH signal exceeding a predetermined received electric field strength has been detected. If it is determined in step S251 that an FH signal has been detected, the process proceeds to step S252.

[0258] In step S252, the FH signal detection unit 106 acquires the received electric field strength information that represents the peak of the detected FH signal.

[0259] In step S253, the FH signal detection unit 106 measures the signal duration of the detected FH signal.

[0260] In step S254, the FH signal detection unit 106 stores information indicating the state of the detected FH signal (for example, the information shown within the FH signal detection unit 106 in Figure 16) in an internal memory (not shown). After step S254, the process proceeds to step S255.

[0261] If it is determined in step S251 that no FH signal has been detected, the process proceeds to step S255.

[0262] Furthermore, the detection operation by the FH signal detection unit 106 may be performed over a maximum period predetermined by the Bluetooth communication standard used to transmit the FH signal.

[0263] In step S255, the communication control unit 104 determines whether a predetermined time has elapsed. If it is determined in step S255 that a predetermined time has elapsed, the process proceeds to step S256.

[0264] In step S256, the communication control unit 104 acquires detection signal status information indicating the state of the FH signal detected within a predetermined time from the built-in memory of the FH signal detection unit 106.

[0265] In step S257, the communication control unit 104 calculates, for example, the interference period based on information indicating the state of the FH signal.

[0266] In step S258, the communication control unit 104 calculates, for example, the interference offset from the start of detection to the timing when the lowest frequency channel that can serve as a reference is detected.

[0267] In step S259, the communication control unit 104 calculates the interference duration, which is the duration of each FH signal.

[0268] In step S260, the communication control unit 104 stores, as COEX information which is information related to coexistence, parameters (for example, information shown in the communication control unit 104 in FIG. 16) in which the FH communication device 12 existing around its own device operates periodically. Thereafter, the detection process of the FH signal ends.

[0269] <<6. Others>> <Effect> As described above, in the present technology, an FH signal is detected from a periodically operating FH communication system, and from the signal detection timing at which the FH signal is detected, the first interference timing that periodically interferes with the frequency hopping signal is predicted, and a frame is transmitted while avoiding the first interference timing.

[0270] Thereby, signal transmission and reception of the wireless LAN can be performed while coexisting with communication using the surrounding FH signals, and operations can be performed while respecting each other's communication.

[0271] Also, in the present technology, information regarding the first interference timing is included in a frame and transmitted to other wireless communication devices.

[0272] Thereby, since the transmission timing on the reception side is adjusted, the transmitted ACK frame can be reliably received.

[0273] In the present technology, a silent period is inserted in the middle of the A-MPDU frame to be transmitted instead of the MPDU.

[0274] Thereby, a frame can be continuously transmitted while coexisting with the FH signal.

[0275] Furthermore, in the present technology, the receiving-side wireless communication device also detects an FH signal and notifies the signal detection status by an ACK frame.

[0276] This allows the receiving end to share information about coexistence and ensures that retransmitted frames are sent reliably.

[0277] Therefore, according to this technology, even if the FH communication system is operating using the entire frequency band, it is possible to perform communication using the frequency resources transmitted by the wireless LAN system while avoiding interference timing of the FH communication system's signals.

[0278] <Example of computer configuration> The series of processes described above can be executed by hardware or by software. When the series of processes are executed by software, the programs that make up the software are installed from a program storage medium onto a computer that is built into dedicated hardware, or a general-purpose personal computer.

[0279] Figure 21 is a block diagram showing an example of the hardware configuration of a computer that executes the series of processes described above by a program.

[0280] The CPU (Central Processing Unit) 301, ROM (Read Only Memory) 302, and RAM (Random Access Memory) 303 are interconnected by a bus 304.

[0281] An input / output interface 305 is further connected to the bus 304. An input unit 306 consisting of a keyboard, mouse, etc., and an output unit 307 consisting of a display, speakers, etc. are connected to the input / output interface 305. In addition, a storage unit 308 consisting of a hard disk, non-volatile memory, etc., a communication unit 309 consisting of a network interface, etc., and a drive 310 that drives removable media 311 are connected to the input / output interface 305.

[0282] In a computer configured as described above, the CPU 301 performs the aforementioned series of processes by loading a program stored in the memory unit 308 into the RAM 303 via the input / output interface 305 and the bus 304 and executing it.

[0283] The program executed by the CPU 301 is recorded on removable media 311, for example, or provided via a wired or wireless transmission medium such as a local area network, the internet, or digital broadcasting, and installed in the storage unit 308.

[0284] The programs executed by the computer may be programs that are processed chronologically in the order described herein, or they may be programs that are processed in parallel or at necessary times, such as when a call is made.

[0285] In this specification, a system refers to a collection of multiple components (devices, modules (parts), etc.), regardless of whether all components are located in the same enclosure. Therefore, multiple devices housed in separate enclosures and connected via a network, and a single device containing multiple modules within a single enclosure, are both considered systems.

[0286] Furthermore, the effects described herein are merely illustrative and not limiting, and other effects may also occur.

[0287] The embodiments of this technology are not limited to those described above, and various modifications are possible without departing from the spirit of this technology.

[0288] For example, this technology can be configured as cloud computing, where a single function is shared and processed collaboratively by multiple devices via a network.

[0289] In addition, each step described in the above flowchart can be executed by one device, or can be executed in cooperation by a plurality of devices.

[0290] Furthermore, when a plurality of processes are included in one step, the plurality of processes included in that one step can be executed by one device, or can be executed in cooperation by a plurality of devices.

[0291] <Example of configuration combination> This technology can also adopt the following configuration. (1) A detection unit that detects a frequency hopping signal from a frequency hopping communication system that operates periodically, A communication control unit that predicts a first interference timing that periodically interferes with the frequency hopping signal from the signal detection timing when the frequency hopping signal is detected, A transmission unit that transmits a frame while avoiding the first interference timing A wireless communication device comprising: (2) [[ID=2)4]]The communication control unit performs control to include information regarding the first interference timing in the frame and transmit it to another wireless communication device. The wireless communication device according to (1) above. (3) The communication control unit performs control to construct the frame so as to insert a silent period at the first interference timing. The wireless communication device according to (1) or (2) above. (4) The communication control unit performs control to suppress the transmission power and temporarily stop the transmission of the frame during the silent period. The wireless communication device according to (3) above. (5) The communication control unit includes information indicating that the frame includes the silent period in the header information of the frame. The wireless communication device according to (3) above. (6) The communication control unit performs control to construct the frame such that the first interference timing coincides with the boundary of a MAC layer protocol data unit (MPDU). The wireless communication device described in (1) or (2) above. (7) The communication control unit performs control to configure the frames as aggregated MAC layer protocol data units (A-MPDUs). A wireless communication device as described in any of the above (1). (8) The communication control unit includes the information regarding the first interference timing in the delimiter portion of the A-MPDU. The wireless communication device described in (7) above. (9) The communication control unit calculates the first interference timing based on the offset information of the signal detection timing, the information on the duration of the frequency hopping signal, and the information on the period in which the frequency hopping signal was detected. A wireless communication device as described in any of (1) to (8) above. (10) If the information transmitted from another wireless communication device that receives the frame contains information regarding a second interference timing in which the other wireless communication device interferes with the frequency hopping signal, the communication control unit calculates the second interference timing based on the information regarding the second interference timing. A wireless communication device as described in any of (1) to (9) above. (11) The communication control unit performs control to transmit the frame while avoiding the second interference timing. The wireless communication device described in (10) above. (12) The communication control unit performs control to retransmit the frame that needs to be retransmitted, while avoiding the second interference timing. The wireless communication device described in (11) above. (13) Wireless communication device, A frequency-hopping signal is detected from a periodically operating frequency-hopping communication system, and a first interference timing is predicted from the signal detection timing at which the frequency-hopping signal is detected, Transmit the frame while avoiding the first interference timing. Wireless communication method. (14) A receiving unit that receives a first frame from another wireless communication device containing information regarding coexistence with frequency-hopping signals detected from a periodically operating frequency-hopping communication system, A communication control unit performs control to transmit a second frame to the other wireless communication device, avoiding a first interference timing in which the other wireless communication device interferes with the frequency hopping signal, based on the information regarding the coexistence. A wireless communication device equipped with the following features. (15) The communication control unit extracts information regarding the first interference timing from the information regarding coexistence, and performs control to transmit the second frame to the other wireless communication device based on the information regarding the first interference timing. The wireless communication device described in (14) above. (16) When the communication control unit detects data destined for the other wireless communication device, it activates the detection unit that detects the frequency hopping signal and predicts a second interference timing in which it interferes with the frequency hopping signal. The wireless communication device described in (14) or (15) above. (17) The system includes a transmitting unit that transmits the second frame containing information about the second interference timing. The wireless communication device described in (16) above. (18) The communication control unit generates the second frame by adding an element containing information about the second interference timing to the ACK information. The wireless communication device described in (16) above. (19) The communication control unit records the second interference timing information if there is undelivered data addressed to it. The wireless communication device described in (18) above. (20) Wireless communication device, A first frame containing information about coexistence with frequency-hopping signals detected from a periodically operating frequency-hopping communication system is received from another wireless communication device. Based on the information regarding coexistence, control is performed to transmit a second frame to the other wireless communication device while avoiding the first interference timing in which the other wireless communication device interferes with the frequency hopping signal. Wireless communication method. [Explanation of Symbols]

[0292] 11, 11-1 and 11-2 Wireless communication devices, 12-1 and 12-2 FH communication devices, 51 Internet connection module, 52 Information input module, 53 Device control module, 54 Information output module, 55 Wireless communication module, 101 Interface, 102 Transmit buffer, 103 Frame construction unit, 104 Communication control unit, 105 Signal transmission processing unit, 106 FH signal detection unit, 107 High-frequency processing unit, 108, 108-1 and 108-2 Antennas, 109 Signal reception processing unit, 110 Frame analysis unit, 111 Receive buffer

Claims

1. A detection unit that detects frequency hopping signals from a periodically operating frequency hopping communication system, A communication control unit predicts a first interference timing that interferes with the frequency hopping signal from the signal detection timing at which the frequency hopping signal is detected, A transmitting unit that transmits a frame while avoiding the first interference timing, and A wireless communication device equipped with the following features.

2. The communication control unit performs control to include the information regarding the first interference timing in the frame and transmit it to another wireless communication device. The wireless communication device according to claim 1.

3. The communication control unit performs control to construct the frame so as to insert a silent period at the first interference timing. The wireless communication device according to claim 1.

4. The communication control unit performs control to reduce the transmission power and temporarily suspend the transmission of the frame during the silent period. The wireless communication device according to claim 3.

5. The communication control unit includes information indicating that the frame contains the silent period in the header information of the frame. The wireless communication device according to claim 3.

6. The communication control unit performs control to construct the frame such that the first interference timing coincides with the boundary of a MAC layer protocol data unit (MPDU). The wireless communication device according to claim 1.

7. The communication control unit performs control to configure the frames as an aggregated MAC layer protocol data unit (A-MPDU). The wireless communication device according to claim 1.

8. The communication control unit includes the information regarding the first interference timing in the delimiter portion of the A-MPDU. The wireless communication device according to claim 7.

9. The communication control unit calculates the first interference timing based on the offset information of the signal detection timing, the information on the duration of the frequency hopping signal, and the information on the period in which the frequency hopping signal was detected. The wireless communication device according to claim 1.

10. If the information transmitted from another wireless communication device that receives the frame contains information regarding a second interference timing in which the other wireless communication device interferes with the frequency hopping signal, the communication control unit calculates the second interference timing based on the information regarding the second interference timing. The wireless communication device according to claim 1.

11. The communication control unit performs control to transmit the frame while avoiding the second interference timing. The wireless communication device according to claim 10.

12. The communication control unit performs control to retransmit the frame that needs to be retransmitted, while avoiding the second interference timing. The wireless communication device according to claim 11.

13. Wireless communication device, A frequency-hopping signal is detected from a periodically operating frequency-hopping communication system, and a first interference timing is predicted from the signal detection timing at which the frequency-hopping signal is detected, Transmitting a frame while avoiding the first interference timing. Wireless communication method.

14. A receiving unit that receives a first frame from another wireless communication device containing information regarding coexistence with frequency-hopping signals detected from a periodically operating frequency-hopping communication system, A communication control unit performs control to transmit a second frame to the other wireless communication device, avoiding a first interference timing in which the other wireless communication device interferes with the frequency hopping signal, based on the information regarding coexistence. A wireless communication device equipped with the following features.

15. The communication control unit extracts information regarding the first interference timing from the information regarding coexistence, and performs control to transmit the second frame to the other wireless communication device based on the information regarding the first interference timing. The wireless communication device according to claim 14.

16. When the communication control unit detects data destined for the other wireless communication device, it activates the detection unit that detects the frequency hopping signal and predicts a second interference timing in which it periodically interferes with the frequency hopping signal. The wireless communication device according to claim 14.

17. The system includes a transmitting unit that transmits the second frame containing information regarding the second interference timing. The wireless communication device according to claim 16.

18. The communication control unit generates the second frame by adding an element containing information about the second interference timing to the ACK information. The wireless communication device according to claim 16.

19. The communication control unit records the second interference timing information if there is undelivered data among the data addressed to it. The wireless communication device according to claim 18.

20. Wireless communication device, A first frame containing information about coexistence with frequency-hopping signals detected from a periodically operating frequency-hopping communication system is received from another wireless communication device. Based on the information regarding coexistence, control is performed to transmit a second frame to the other wireless communication device while avoiding the first interference timing in which the other wireless communication device interferes with the frequency hopping signal. Wireless communication method.

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