Communication device, communication control method, and program

Abstract

A communication device (2) comprises a peripheral detection unit (200), a contention determination unit (202), and a communication timing change request unit (203). The peripheral detection unit (200) detects advertisements from one or more sensor terminals and estimates the reception timing of each advertisement. The contention determination unit (202) determines whether there is contention between communication with a central apparatus and reception of advertisements from each sensor terminal. The communication timing change request unit (203) requests the central apparatus to change a communication timing when it is determined by the contention determination unit (202) that there is contention between reception of advertisements from any of the sensor terminals and communication with the central apparatus.

Description

Communication device, communication control method, and program

[0001] The present disclosure relates to a communication device, a communication control method, and a program.

[0002] As described in Patent Document 1, a technology has been known in the past in which a communication device that operates as either a master or a slave controls the period during which it operates as a slave depending on the communication status with electronic devices other than the electronic device that is wirelessly connected to the communication device.

[0003] International Publication No. 2020 / 096066

[0004] Incidentally, a communication system is known in which a communication device in a central role receives advertisements from a plurality of peripheral devices such as sensor terminals in an advertisement channel method, and also communicates with the central devices in a peripheral role in a data channel method.

[0005] In the advertisement channel method, the communication device communicates without knowing the communication status with each peripheral device, i.e., the timing of receiving advertisements from each peripheral device. Therefore, in the conventional communication system with the above configuration, it is difficult for the communication device to appropriately adjust the timing of operating as a peripheral, i.e., the timing of communication with the central device.

[0006] The present disclosure has been made to solve the above problem, and aims to provide a communication device, a communication control method, and a program that are capable of appropriately adjusting communication timing with a central device.

[0007] In order to achieve the above object, the communication device according to the present disclosure comprises: a reception timing estimation means for detecting one or more peripheral devices and estimating the reception timing of an advertisement from each of the detected peripheral devices; a conflict determination means for determining whether there is a conflict between communication with a central device and reception of an advertisement from each peripheral device; and a communication timing change request means for requesting a change in communication timing from the central device when the conflict determination means determines that there is a conflict between reception of an advertisement from any of the peripheral devices and communication with the central device.

[0008] According to the present disclosure, it is possible to appropriately adjust the timing of communication with the central device.

[0009] FIG. 1 is a diagram showing the overall configuration of a communication system in an embodiment. Block diagram showing the hardware configuration of a communication device in an embodiment. Block diagram showing the hardware configuration of a central device in an embodiment. Block diagram showing the hardware configuration of a sensor terminal in an embodiment. Block diagram showing the functional configuration of a communication device in an embodiment.

[0010] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0011] 1 is a diagram showing the overall configuration of a communication system 1 according to an embodiment. The communication system 1 includes a communication device 2, a central device 3, and one or more sensor terminals 4.

[0012] <Communication Device 2> The communication device 2 is an example of a communication device according to the present disclosure. The communication device 2 collects data indicating values ​​measured by the sensor terminals 4 (hereinafter referred to as "sensor data") from each sensor terminal 4 and transmits the collected data to the central device 3. The communication device 2 also accepts various settings and operations for itself from the central device 3, and performs program updates and the like based on data received from the central device 3. If the communication device 2 is a communication adapter connected to a device such as an air conditioner or lighting device, the communication device 2 relays data exchanged between the device and the central device 3.

[0013] 2, the communication device 2 includes, as its hardware configuration, a communication interface 20, a CPU (Central Processing Unit) 21, a ROM (Read-Only Memory) 22, a RAM (Random-Access Memory) 23, and an auxiliary storage device 24. These components are interconnected via a bus 25. The communication interface 20 is hardware for wireless communication with other devices using a predetermined short-range wireless communication method, and in this embodiment, is hardware for performing Bluetooth (registered trademark) communication.

[0014] The CPU 21 performs overall control of the communication device 2. The functions of the communication device 2 realized by the CPU 21 will be described in detail later. The ROM 22 stores read-only programs such as the BIOS. The RAM 23 is used as a work area for the CPU 21. The auxiliary storage device 24 is composed of a readable / writable nonvolatile semiconductor memory, a hard disk drive (HDD), or the like. Examples of the readable / writable nonvolatile semiconductor memory include an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), and a flash memory. The auxiliary storage device 24 stores a communication control program, which is a program for realizing each function of the communication device 2 described later, and data used when the communication control program is executed.

[0015] The communication device 2 can acquire the above-mentioned communication control program or an update program for updating the communication control program via communication from the central device 3 or another device (not shown). These programs can also be stored and distributed on a computer-readable recording medium such as a CD-ROM (Compact Disc Read-Only Memory), a DVD (Digital Versatile Disc), a magneto-optical disk, a USB (Universal Serial Bus) memory, a HDD, an SSD (Solid-State Drive), or a memory card. When such a recording medium is directly or indirectly attached to the communication device 2, the communication device 2 can read the communication control program or update program from the recording medium and install it in itself.

[0016] <Central Device 3> The central device 3 is an example of a central device according to the present disclosure. The central device 3 is, for example, a smart device such as a smartphone or a tablet terminal, a notebook PC (Personal Computer), an air conditioner remote control, or a lighting remote control. The central device 3 establishes a connection with the communication device 2 and initiates data communication. That is, the central device 3 communicates with the communication device 2 using a so-called data channel method.

[0017] 3 , the central device 3 includes a display 30, an operation reception unit 31, a communication interface 32, a CPU 33, a ROM 34, a RAM 35, and an auxiliary storage device 36. These components are connected to one another via a bus 37. The display 30 includes a display device such as a liquid crystal display or an organic EL (Electroluminescence) display. Under the control of the CPU 33, the display 30 displays an operation screen for the communication device 2, a screen for displaying sensor data acquired from the communication device 2, and the like.

[0018] The operation reception unit 31 includes one or more input devices such as push buttons, a touch panel, a touch pad, a keyboard, and a mouse, and receives operation input from a user and outputs a signal related to the received operation to the CPU 33. The communication interface 32 is hardware for wireless communication with other devices using a predetermined short-range wireless communication method, and in this embodiment, is hardware for Bluetooth (registered trademark) communication. The CPU 33 performs overall control of the central device 3.

[0019] The ROM 34 stores read-only programs such as the BIOS. The RAM 35 is used as a work area for the CPU 33. The auxiliary storage device 36 is composed of a readable / writable nonvolatile semiconductor memory, a HDD, etc. Examples of the readable / writable nonvolatile semiconductor memory include an EPROM, an EEPROM, and a flash memory. The auxiliary storage device 36 stores various programs, including a program for operating the communication device 2, and data used when these programs are executed.

[0020] <Sensor Terminal 4> The sensor terminal 4 is an example of a peripheral device according to the present disclosure. As shown in Fig. 4, the sensor terminal 4 includes a sensor unit 40, a communication interface 41, a CPU 42, a ROM 43, a RAM 44, and an auxiliary storage device 45. These components are connected to each other via a bus 46.

[0021] The sensor unit 40 is a circuit for measuring environmental information around the sensor unit 40. The environmental information includes, for example, air temperature, humidity, CO ２ These include concentration, odor, PM (Particulate Matter), thermal images, illuminance, etc. The communication interface 41 is hardware for wireless communication with other devices using a predetermined short-range wireless communication method, and in this embodiment is hardware for Bluetooth (registered trademark) communication.

[0022] The CPU 42 performs overall control of the sensor terminal 4. The ROM 43 stores read-only programs such as the BIOS. The RAM 44 is used as a work area for the CPU 42. The auxiliary storage device 45 is composed of, for example, a readable / writable non-volatile semiconductor memory such as an EPROM, an EEPROM, or a flash memory. The auxiliary storage device 45 stores a program for measuring environmental information and wirelessly transmitting the measurement results, as well as data used when the program is executed.

[0023] The sensor terminal 4 configured as described above measures environmental information around where it is installed, and broadcasts an advertisement (i.e., sensor data) including its own identifier, a UUID (Universally Unigue Identifier), and the measured value at a preset time interval (i.e., advertisement interval).

[0024] 5, the communication device 2 includes, as characteristic functions, a peripheral detection unit 200, a connection management unit 201, a conflict determination unit 202, and a communication timing change request unit 203. These functional units are realized by the CPU 21 executing the above-described communication control program stored in the auxiliary storage device 24.

[0025] The peripheral detection unit 200 is an example of a reception timing estimation means according to the present disclosure. When a predetermined condition is met, the peripheral detection unit 200 detects a peripheral device, i.e., a sensor terminal 4, and executes a process of estimating the reception timing of an advertisement from the detected sensor terminal 4. The above condition is met when any of the following conditions (1) to (3) is met: (1) When short-range wireless communication of the communication device 2 is enabled and the power is turned on; (2) When short-range wireless communication of the communication device 2 is switched from disabled to enabled; or (3) When an operation to instruct peripheral detection to be executed is performed by the user.

[0026] In detail, the peripheral detection unit 200 performs a scan (specifically, a passive scan) to receive an advertisement transmitted from a surrounding sensor terminal 4. Then, the peripheral detection unit 200 extracts and acquires an identifier (in this embodiment, a UUID) from the received advertisement. The peripheral detection unit 200 registers the acquired UUID in a peripheral management table (see FIG. 6 ). The peripheral management table is a data table for managing the reception timing of peripheral devices from which sensor data is to be acquired, i.e., the sensor terminals 4, and is stored in the auxiliary storage device 24. Reception timing information is registered in the peripheral management table for each UUID. The reception timing information includes a starting time and a reception period.

[0027] The peripheral detection unit 200 repeats scanning until a predetermined time (hereinafter referred to as the "peripheral detection time") has elapsed, thereby estimating the reception period, i.e., the advertising interval, of the advertisements corresponding to each UUID, i.e., the advertisements transmitted from each sensor terminal 4. The peripheral detection unit 200 estimates the reception period of the advertisements from each sensor terminal 4 by calculating the average of the reception periods (Tn) of advertisements from the same sender (i.e., advertisements with the same UUID) detected within the peripheral detection time.

[0028] However, since the advertising interval includes a random time (advertising delay of 0 to 10 ms) to avoid collision with other advertisements, the peripheral detection unit 200 estimates the reception period of advertisements from each sensor terminal 4 by subtracting the average advertising delay (i.e., 5 ms) from the average reception period (Tn) as shown in the following formula.

[0029]

[0030] The peripheral detection unit 200 registers the estimated reception period in the peripheral management table. The peripheral detection unit 200 also registers the time when the most recent advertisement was received from the sensor terminal 4 in question in the peripheral management table as the starting time. After the peripheral detection time has elapsed, the peripheral detection unit 200 periodically receives advertisements (i.e., sensor data) of the UUIDs registered in the peripheral management table, sorts the received sensor data by UUID in chronological order, and stores the sorted data in a sensor data table (not shown). The sensor data table is a data table stored in the auxiliary storage device 24.

[0031] The connection management unit 201 establishes a connection with the central device 3. When establishing the connection, the connection management unit 201 extracts and acquires a connection interval and an offset from a connection request received from the central device 3. As shown in Fig. 7 , the connection interval indicates the communication interval with the central device 3. The offset indicates the interval from when the connection request is received from the central device 3 until the first data is received, in other words, the interval from when the connection request is received until communication with the central device 3 starts.

[0032] The connection management unit 201 calculates the time when communication with the central device 3 will start (hereinafter referred to as the "communication start time") based on the time when the connection request was received and the acquired offset. The connection management unit 201 saves communication timing information (see FIG. 8) including the calculated communication start time and the acquired connection interval in the auxiliary storage device 24.

[0033] The conflict determination unit 202 is an example of conflict determination means according to the present disclosure. The conflict determination unit 202 determines whether or not there is a conflict between communication with the central device 3 and reception of an advertisement from each sensor terminal 4. In detail, the conflict determination unit 202 determines, for each sensor terminal 4, whether or not there is a conflict between the timing of communication with the central device 3 (specifically, the timing of receiving data from the central device 3) and the timing of receiving an advertisement, based on the communication timing information stored in the auxiliary storage device 24 and the reception timing information corresponding to each sensor terminal 4 stored in the peripheral management table.

[0034] Specifically, the conflict determination unit 202 estimates whether or not there is a possibility of overlap (in other words, collision) between future reception of an advertisement from the sensor terminal 4 and future reception of data from the central device 3 within a predetermined determination time from the current time, and if it estimates that there is a possibility of overlap, it counts the number of times this occurs. The above determination time is sufficiently longer than the connection interval and the reception cycle of each sensor terminal 4.

[0035] In the above estimation, the conflict determination unit 202 does not directly compare the estimated reception time of each advertisement from the sensor terminal 4 within the above determination time with the estimated reception time of each data from the central device 3, but determines whether or not the reception of data from the central device 3 overlaps within a certain time range (for example, 5 ms, which is the average advertisement delay) from the reception time of each advertisement. If the counted number of times is equal to or greater than a certain number, the conflict determination unit 202 determines that there is a conflict between the reception of the advertisement from the sensor terminal 4 and communication with the central device 3.

[0036] When the conflict determination unit 202 determines that there is a conflict between the reception of an advertisement from any of the sensor terminals 4 and communication with the central device 3, it notifies the communication timing change request unit 203 of that fact. The communication timing change request unit 203 is an example of a communication timing change request means according to the present disclosure. When the conflict determination unit 202 determines that there is a conflict between the reception of an advertisement from any of the sensor terminals 4 and communication with the central device 3, the communication timing change request unit 203 requests the central device 3 to change the communication timing. In detail, the communication timing change request unit 203 transmits a specified message (hereinafter referred to as a "change request message") for requesting a change in the communication timing to the central device 3.

[0037] Upon receiving the change request message, the central device 3 changes at least one of the offset and the connection interval, and transmits a change completion message to the communication device 2. The connection management unit 201 extracts and acquires the connection interval and offset from the received change completion notification. The connection management unit 201 then updates the communication timing information stored in the auxiliary storage device 24 based on the acquired connection interval and offset. When the communication timing information is updated, the conflict determination unit 202 performs conflict determination again. If the conflict determination unit 202 determines that there is a conflict, the communication timing change request unit 203 again requests the central device 3 to change the communication timing. Thereafter, the above series of processes are repeated until the conflict determination unit 202 determines that there is no conflict.

[0038] 9 is a flowchart showing the steps of the peripheral detection process executed by the communication device 2. The communication device 2 executes the following peripheral detection process when the short-range wireless communication of the communication device 2 is enabled and the power is turned on, when the short-range wireless communication of the communication device 2 is switched from disabled to enabled, or when the user performs an operation to instruct the execution of peripheral detection.

[0039] (Step S100) The communication device 2 performs a scan. After that, the process of the communication device 2 proceeds to step S101.

[0040] (Step S101) The communication device 2 determines whether or not it has received an advertisement from any sensor terminal 4. If an advertisement has been received (step S101; YES), the processing of the communication device 2 proceeds to step S102. If an advertisement has not been received (step S101; NO), the processing of the communication device 2 returns to step S100.

[0041] (Step S102) The communication device 2 acquires an identifier (i.e., UUID) from the received advertise and determines whether the acquired identifier has been registered in the peripheral management table. If the acquired identifier has not been registered in the peripheral management table (Step S102; NO), the process of the communication device 2 proceeds to Step S103. If the acquired identifier has been registered in the peripheral management table (Step S102; YES), the process of the communication device 2 proceeds to Step S104.

[0042] (Step S103) The communication device 2 registers the acquired identifier in the peripheral management table (see FIG. 6). After that, the process of the communication device 2 proceeds to step S106.

[0043] (Step S104) The communication device 2 estimates the period for receiving an advise from the sensor terminal 4. After that, the process of the communication device 2 proceeds to step S105.

[0044] (Step S105) The communication device 2 registers the estimated reception cycle and start time in the peripheral management table. After that, the process of the communication device 2 proceeds to step S106.

[0045] (Step S106) The communication device 2 determines whether the time elapsed since the start of the peripheral detection process has reached the peripheral detection time. If the peripheral detection time has not elapsed (step S106; NO), the process of the communication device 2 returns to step S100. If the peripheral detection time has elapsed (step S106; YES), the communication device 2 ends the peripheral detection process.

[0046] <Connection Establishment Processing> FIG. 10 is a flowchart showing the procedure of connection establishment processing executed by the communication device 2 to establish a connection with the central device 3.

[0047] (Step S200) The communication device 2 broadcasts an advertisement including its own UUID. After that, the process of the communication device 2 proceeds to step S201.

[0048] (Step S201) The communication device 2 determines whether or not a connection request has been received from the central device 3. If a connection request has been received (step S201; YES), the process of the communication device 2 proceeds to step S202. If a connection request has not been received (step S201; NO), the process of the communication device 2 returns to step S200.

[0049] (Step S202) The communication device 2 extracts and acquires the connection interval and offset from the received connection request. After that, the process of the communication device 2 proceeds to step S203.

[0050] (Step S203) The communication device 2 establishes a connection with the central device 3. After that, the process of the communication device 2 proceeds to step S204.

[0051] (Step S204) The communication device 2 calculates the communication start time from the time when the connection request was received and the acquired offset. After that, the process of the communication device 2 proceeds to step S205.

[0052] (Step S205) The communication device 2 stores the communication timing information (see FIG. 8) including the communication start time and the acquired connection interval in the auxiliary storage device 24. Thereafter, the communication device 2 ends the connection establishment process.

[0053] 11 is a flowchart showing the procedure of the conflict determination process executed by the communication device 2. The communication device 2 executes the following conflict determination process when a connection with the central device 3 is established and whenever the communication timing information (see FIG. 8) is changed.

[0054] (Step S300) The communication device 2 reads out, one by one, the reception timing information corresponding to each sensor terminal 4 (i.e., each UUID) from the peripheral management table (see FIG. 6). After that, the process of the communication device 2 proceeds to step S301.

[0055] (Step S301) Based on the read reception timing information and the communication timing information stored in the auxiliary storage device 24, the communication device 2 determines whether reception of an advertise from the sensor terminal 4 corresponding to the reception timing information conflicts with communication with the central device 3. If reception of the advertise does not conflict with communication with the central device 3 (step S301; NO), the processing of the communication device 2 transitions to step S302. If reception of the advertise conflicts with communication with the central device 3 (step S301; YES), the processing of the communication device 2 transitions to step S303.

[0056] (Step S302) The communication device 2 determines whether all the reception timing information has been read from the peripheral management table. If all the reception timing information has not been read (step S302; NO), the communication device 2 returns to step S300. If all the reception timing information has been read (step S302; YES), the communication device 2 ends the contention determination process.

[0057] (Step S303) The communication device 2 requests a change in the communication timing from the central device 3. After that, the communication device 2 ends the contention determination process.

[0058] As described above, in the communication system 1 of this embodiment, the communication device 2 estimates the reception timing of an advertisement from each sensor terminal 4, and determines whether there is a conflict between communication with the central device 3 and reception of an advertisement from each sensor terminal 4. If it determines that there is a conflict between reception of an advertisement from any sensor terminal 4 and communication with the central device 3, it requests the central device 3 to change the communication timing. This makes it possible to appropriately adjust the communication timing with the central device 3, and prevents sensor data from being missed from the sensor terminal 4.

[0059] (Variation 1) The communication device 2 may be configured to estimate the reception timing only for an advertisement from a specific sensor terminal 4. Specifically, in the peripheral detection process (see FIG. 9 ), if the identifier (i.e., UUID) of a received advertisement does not match the identifier of a predetermined sensor data to be acquired, the communication device 2 may discard the advertisement and not register the identifier in the peripheral management table.

[0060] (Variant 2) When the communication device 2 needs to acquire the sensor data at a period longer than the reception period of the advertisement from the sensor terminal 4 (the reception period of the advertisement × n (n > 1)) for the purpose of using the sensor data, the communication device 2 may receive the sensor data (i.e., the advertisement) at that period and determine whether or not there is a conflict based on that period.

[0061] For example, even if a sensor terminal 4 measuring air temperature transmits sensor data as an advertisement every 10 seconds, if it is necessary and sufficient for the communication system 1 to acquire sensor data every minute from the sensor terminal 4, the communication device 2 will receive the advertisement every minute from the sensor terminal 4. Furthermore, in step S301 of the conflict determination process (see FIG. 11 ), the communication device 2 determines whether or not the reception of the advertisement at a one-minute cycle for the sensor terminal 4 conflicts with communication with the central device 3.

[0062] (Variation 3) When the communication device 2 determines in step S301 of the conflict determination process (see FIG. 11 ) that reception of an advertise from a sensor terminal 4 conflicts with communication with the central device 3 (step S301; YES), the communication device 2 may calculate communication timing (i.e., connection interval and offset) to prevent reception of an advertise from any sensor terminal 4 from conflicting with communication with the central device 3, and may transmit a change request message including the calculated communication timing to the central device 3. Note that the communication device 2 may calculate only either the connection interval or the offset.

[0063] Upon receiving the change request message, the central device 3 changes at least one of the offset and the connection interval in consideration of the communication timing included in the change request message, and transmits a change completion message to the communication device 2. With this configuration, it is possible to reduce the number of times that the change request message is transmitted from the communication device 2 to the central device 3.

[0064] (Variation 4) The communication device 2 may periodically execute a peripheral detection process (see FIG. 9). In this case, when a new UUID (i.e., a new sensor terminal 4) that is not registered in the previous peripheral management table (see FIG. 6) is detected, the communication device 2 executes a conflict determination process (see FIG. 11). This configuration enables the communication device 2 to automatically respond to the addition of a new peripheral device after starting operation.

[0065] (Variant 5) The communication device 2 manages the most recent reception time of an advertisement from each sensor terminal 4 using a peripheral management table or other table, and if no advertisement has been received from the sensor terminal 4 for a predetermined time (for example, the reception period of the advertisement x n) since the last reception, the communication device 2 may determine that the sensor terminal 4 has left and delete the record corresponding to the sensor terminal 4 from the peripheral management table.

[0066] (Variation 6) A priority may be set in advance for each communication type, and if the priority of the communication type in communication with the central device 3 is higher than the priority in communication with each sensor terminal 4 (i.e., the priority of the sensor data), the communication device 2 may prioritize communication with the central device 3. Specifically, in this case, the communication device 2 does not request the central device 3 to change the communication timing. The priority for each communication type is registered in advance in a communication priority table (see FIG. 12 ) stored in the auxiliary storage device 24. In communication with the central device 3, information indicating the communication type is included in the data from the central device 3.

[0067] For example, when the communication type in communication with the central device 3 is a setting or program update of the communication device 2, the communication device 2 does not request a change in communication timing from the central device 3 even if there is a conflict with reception of an advertisement from the sensor terminal 4. Alternatively, when the communication type in communication with the central device 3 is a setting or program update of the communication device, the communication device 2 may avoid executing the conflict determination process (see FIG. 11 ).

[0068] (Variation 7) All or part of the functional units (see FIG. 5) of the communication device 2 may be realized by dedicated hardware, such as a single circuit, a composite circuit, a programmed processor, an ASIC (Application-Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination thereof.

[0069] The technical ideas according to the above-described modifications may be realized independently or in appropriate combination.

[0070] The present disclosure allows various embodiments and modifications without departing from the broad spirit and scope. Furthermore, the above-described embodiments are intended to explain the present disclosure and do not limit the scope of the present disclosure. In other words, the scope of the present disclosure is defined by the claims, not the embodiments. Various modifications made within the scope of the claims and within the meaning of the disclosure equivalent thereto are considered to be within the scope of the present disclosure.

[0071] The present disclosure can be suitably adopted in an apparatus that performs short-range wireless communication with a central device and multiple peripheral devices.

[0072] REFERENCE SIGNS LIST 1 Communication system, 2 Communication device, 3 Central device, 4 Sensor terminal, 20, 32, 41 Communication interface, 21, 33, 42 CPU, 22, 34, 43 ROM, 23, 35, 44 RAM, 24, 36, 45 Auxiliary storage device, 25, 37, 46 Bus, 30 Display, 31 Operation acceptance unit, 40 Sensor unit, 200 Peripheral detection unit, 201 Connection management unit, 202 Conflict determination unit, 203 Communication timing change request unit

Claims

1. A communication device comprising: a reception timing estimation means for detecting one or more peripheral devices and estimating the reception timing of an advertisement from each of the detected peripheral devices; a conflict determination means for determining whether there is a conflict between communication with a central device and the reception of an advertisement from each peripheral device; and a communication timing change request means for requesting a change in communication timing from the central device when the conflict determination means determines that there is a conflict between the reception of an advertisement from any of the peripheral devices and communication with the central device.

2. The communication device according to claim 1, wherein, when the conflict determination means determines that a conflict exists, the communication timing change request means calculates a communication timing to prevent a conflict between communication with the central device and reception of advertisements from each of the peripheral devices, and notifies the central device of the calculated communication timing when requesting a change in the communication timing from the central device.

3. The communication device according to claim 1 or 2, wherein the reception timing estimation means periodically detects peripheral devices and estimates the reception timing of advertisements from the detected peripheral devices, and when a new peripheral device is detected by the reception timing estimation means, the conflict determination means determines whether there is a conflict between communication with the central device and reception of advertisements from each of the peripheral devices.

4. A communication device according to any one of claims 1 to 3, wherein a priority is set in advance for each communication type, and when the priority of a communication type for communication with the central device is higher than the priority of a communication type for communication with each of the peripheral devices, the communication device prioritizes communication with the central device.

5. The communication device according to any one of claims 1 to 4, wherein the reception timing estimation means estimates the reception timing of an advertisement from a specific peripheral device.

6. A communication control method, in which a reception timing estimation means detects one or more peripheral devices and estimates the reception timing of an advertisement from each of the detected peripheral devices, a conflict determination means determines whether there is a conflict between communication with a central device and reception of an advertisement from each peripheral device, and a communication timing change request means, if the conflict determination means determines that there is a conflict between reception of an advertisement from any peripheral device and communication with the central device, requests a change in communication timing from the central device.

7. A program that causes a computer to function as: a reception timing estimation means that detects one or more peripheral devices and estimates the reception timing of an advertisement from each detected peripheral device; a conflict determination means that determines whether there is a conflict between communication with a central device and the reception of an advertisement from each peripheral device; and a communication timing change request means that requests the central device to change the communication timing when the conflict determination means determines that there is a conflict between the reception of an advertisement from any peripheral device and communication with the central device.

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