JP2011188339A - Communication apparatus, communication control method, and communication control program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication apparatus, a communication control method, and a communication control program, which can efficiently determine channels for communication. <P>SOLUTION: When a communication start instruction is inputted (at S102: YES), a use frequency data table where the past use frequency of each channel is registered for each predetermined time is referred to, and a channel which can be acted is presumed (at S104). When there is a channel presumed to be a channel which can be acted (at S105: YES), the use frequency registered in the use frequency data table is referred to and grouping is performed (at S106). Groups of low use frequencies are selected as groups subjected to scanning (at S107). Further, the order of scanning is determined among the groups so that the channels are scanned. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a communication device, a communication control method, and a communication control program that execute channel scanning before emitting radio waves for transmitting and receiving data and determine a channel for communication.

  2. Description of the Related Art Conventionally, in order to prevent interference with other communications, a communication apparatus that performs channel scanning and determines a channel for communication is known in order to check an empty channel before starting data transmission / reception. For example, the channel selection circuit described in Patent Document 1 stores preset priority channel information and the past use count. The priority channel information is set in advance so that a channel that does not overlap with a channel frequently used in other wireless systems used in the vicinity is given priority. Then, the channel selection circuit detects a free channel by referring to the priority channel information and the past use count.

JP 2009-260792 A

  However, the degree of congestion of the communication band varies from time to time, and there are times when the communication band is congested, and conversely, there are times when the communication band is not congested. In the above channel selection circuit, a channel that has been used in the past is taken into account, but a channel that has been used in the past may be used depending on the time zone. For this reason, if a channel scan is executed when the communication band is congested, it takes time to select an empty channel. That is, it is not possible to efficiently determine a channel for communication. As a result, there is a problem that the load on the CPU increases and the operation becomes unstable or the power consumption increases.

  An object of the present invention is to provide a communication device, a communication control method, and a communication control program that can efficiently determine a channel for communication.

  The communication device according to the first aspect of the present invention performs a scan for detecting whether or not a plurality of channels for performing wireless communication are used by a device that performs other communication, and sets the channel for performing communication. The communication device to be determined is a past time zone in which the scan is executed and a use frequency that is a frequency at which each channel is used by a device that performs another communication in the past time zone. Storage control means for storing in the storage device a plurality of data associated with each of the channels, and each channel in the past time zone that is the same as the current time zone in the data stored in the storage device by the storage control means Order determining means for determining the order of the channels on which the scan is executed, and the channel determined by the order determining means. Executing the scan Le order, and a channel determining means for determining the communicable said channel.

  In this case, the scanning order can be determined by referring to the frequency of use of each channel in the past time zone that is the same as the current time zone in the data. Therefore, it is possible to scan a channel that is likely to be used at the current time. Therefore, the channel for communication can be determined efficiently.

  In the communication device, the order determination unit refers to the frequency of use of each channel in the past time zone that is the same as the current time zone in the data stored in the storage device, and You may determine the order which performs the said scan in order of the said channel with little use frequency in the said past time slot | zone same as time.

  In this case, the scan can be executed in the order of the low frequency of use in the past. For this reason, the channel which communicates can be determined efficiently.

  In the communication device, the order determining means refers to the use frequency of each channel in the past time zone that is the same as the current time zone in the data stored in the storage device, and is adjacent to the data A first condition that is a condition that both of the use frequencies of the channels are channels of a first use frequency that is a predetermined use frequency, and the use frequency in the channel having a higher frequency among the adjacent channels; The second condition, which is a condition that either one of the use frequencies in the low frequency channel is the channel having the first frequency or less, and the use frequency is the first frequency or less continuously for a predetermined time or more. Predetermined from the third condition, which is a channel condition, the highest frequency in the communicable frequency band, and the lowest frequency A fourth condition that is a condition that the channel is separated by a frequency width or more, and a fifth condition that is a condition that the frequency of use in the past time period that is the same as the current time period is a channel that is less than or equal to the first frequency. The order of the channels for executing the scan may be determined with reference to at least one of the conditions.

  In this case, if the frequency is equal to or lower than the first frequency, there is a high possibility that the channel is not used. Further, if adjacent channels are not used, there is a high possibility that the communication quality will be good. In other words, scanning can be performed with priority given to channels with high communication quality and channels that are not likely to be used.

  In the communication apparatus, the order determination means includes a channel satisfying the first condition, a channel satisfying the second condition, a channel satisfying the third condition, a channel satisfying the fourth condition, and a condition satisfying the fifth condition. The order in which the scans are executed may be determined in the order of channels.

  In this case, it is possible to determine the order in which scans are performed by giving priority to channels with high communication quality and channels that are not likely to be used.

  In the communication apparatus, when the channel determination unit performs the scan in the order of the channels determined by the order determination unit, the channel determination unit measures a reception signal strength of a radio signal in the channel, and the measured reception When the signal strength is equal to or higher than a predetermined threshold, the scan of the channels in the next order is performed, and when the measured received signal strength is smaller than the threshold, it may be determined as a communicable channel .

  In this case, if the received signal strength is greater than or equal to the threshold, the channel is being used by another device. Therefore, scanning is continued. If the received signal strength is less than the threshold, the channel is not being used by another device. Therefore, it can be determined as a communicable channel. That is, it is possible to determine whether or not the channel is currently used based on the received signal strength.

  The communication device refers to the frequency of use of the channel in the past time zone that is the same as the current time zone in the data stored in the storage device, and the past data that is the same as the current time zone. A frequency determining means for determining whether or not the channel having a usage frequency in a time zone equal to or less than a second frequency, which is a predetermined frequency, is provided, and the past that is the same as the current time zone by the frequency determining means When it is determined that the channel whose usage frequency is less than or equal to the second frequency does not exist, the order determination unit does not determine the order, and the channel determination unit can communicate The channel in which the channel is not determined and the frequency of use is less than or equal to the second frequency in the past time zone that is the same as the current time zone. If but it is determined to exist, the order determining unit determines the order, the channel determining means may determine a communicable said channel.

  In this case, if there is no channel whose usage frequency is equal to or lower than the second frequency in the same past time zone as the current time zone, there is a high possibility that there is no usable channel, and therefore no scan is executed. For this reason, the load on the CPU can be reduced and the power consumption can be reduced.

  In the communication apparatus, when the frequency determining means determines that the channel whose usage frequency in the past time zone is the second frequency or less is the same as the current time zone, it can be used. You may further provide the display control means to display on a display screen that possibility that there is no channel is high.

  In this case, if there is no channel whose usage frequency is less than or equal to the second frequency in the same past time zone as the current time zone, there is a high possibility that there is no usable channel, so there is a possibility that there is no usable channel. Is displayed on the display screen. As a result, it is possible to notify the user that there is a high possibility that there is no usable channel.

In the communication apparatus, the communication device further includes an input unit for inputting an instruction as to whether or not to execute the scan from a user, and the frequency determination unit uses the frequency of use in the past time zone that is the same as the current time zone. However, when it is determined that the channel having the second frequency or less does not exist, when the user inputs an instruction not to perform the scan through the input unit, the order determining unit Without determining the order
The channel determining means does not determine the communicable channel, and when an instruction to perform the scan is input by a user via the input means, the order determining means determines the order, The channel determination means may determine the channel through which communication is possible.

  In this case, if there is no channel whose usage frequency is equal to or lower than the second frequency in the same time zone as the current time zone, there is a high possibility that there is no usable channel. However, if there is an instruction from the user, the scan can be executed.

  In the communication device, the communication device is the same type of communication device as the communication device, and is transmitted from the other communication device when another communication device including the storage device that stores the data exists in the same environment. Data storage control means for receiving the data and storing the data in the storage device of the communication device.

  In this case, data created by another communication device can be stored in the storage device of the communication device. For this reason, the communication apparatus can determine the channel which communicates efficiently by using the data which the other communication apparatus produced.

  In the communication apparatus, when another communication apparatus that is the same type of communication apparatus as the communication apparatus and includes the storage device that stores the data exists in the same environment, the other communication apparatus performs the scan. Scan determining means for determining whether or not the other communication apparatus is executing the scan when the scan determining means determines that the scan determining means is executing the scan. And the channel determining means executes the scan and determines the communicable channel when the scan determining means determines that the other communication device is not executing the scan. May be.

  In this case, it is possible to prevent the communication device and another communication device from performing the same scanning timing. For this reason, it can prevent that a communication apparatus and another communication apparatus select the same channel simultaneously.

  In the communication control method according to the second aspect of the present invention, the channel for performing communication by performing a scan to detect whether or not a plurality of channels for performing wireless communication is used by a device that performs other communication A communication control method executed in a communication device for determining the past time zone in which the scan was executed, and a frequency at which each channel was used by a device performing other communication in the past time zone. A storage control step for storing data associated with a plurality of usage frequencies for each channel in the storage device, and the past in the data stored in the storage device by the storage control means that is the same as the current time zone An order determination step for determining the order of the channels on which the scan is performed with reference to the frequency of use of the channels in the time period of Serial executing the scan order of the channels is determined by the order determination step, and a channel determining step of determining a communicable said channel.

  In this case, the scanning order can be determined by referring to the frequency of use of each channel in the past time zone that is the same as the current time zone in the data. Therefore, it is possible to scan a channel that is likely to be used at the current time. Therefore, the channel for communication can be determined efficiently.

  The communication control program according to the third aspect of the present invention performs the scan for detecting whether or not a plurality of channels for performing wireless communication are used by a device that performs other communication, and performs the communication A communication control program executed in a communication device for determining the channel of each channel by a device that performs other communication in the past time zone in which the scan was performed and in the past time zone. A storage control step for storing in the storage device a plurality of data, each of which is a frequency of use, that is associated with each channel, and the current data in the data stored in the storage device by the storage control means The channel that executes the scan with reference to the frequency of use of the channels in the past time zone that is the same as the time zone. And order determining step of determining the order of, executing the scan order of the channel determined by the order determination step, to perform a channel determining step of determining a communicable said channel.

  In this case, the scanning order can be determined by referring to the frequency of use of each channel in the past time zone that is the same as the current time zone in the data. Therefore, it is possible to scan a channel that is likely to be used at the current time. Therefore, the channel for communication can be determined efficiently.

1 is a schematic diagram showing a physical configuration of a communication device 1. FIG. 2 is a schematic diagram showing an electrical configuration of the communication device 1. FIG. 3 is a schematic diagram showing a storage area of a flash memory 24. FIG. It is a schematic diagram which shows the use frequency data table. 6 is a schematic diagram showing a group number data table 52. FIG. 6 is a schematic diagram showing a weighting data table 53. FIG. It is a flowchart which shows a main process. It is a flowchart which shows a main process. It is a schematic diagram which shows the group data table. 4 is a diagram illustrating an example of an image displayed on a display 11. FIG. 3 is a graph showing a graph 60. It is a schematic diagram showing a standby time data table 55. It is a flowchart which shows an access point process. It is a flowchart which shows a master / slave setting process. It is a flowchart which shows the modification of the main process shown in FIG.

  Hereinafter, an embodiment of a communication apparatus according to the present invention will be described with reference to the drawings. These drawings are used for explaining the technical features that can be adopted by the present invention, and the configuration of the apparatus described, the flowcharts of various processes, and the like are not intended to be limited thereto. It is just an illustrative example.

  An overview of the communication device 1 will be described with reference to FIG. The communication device 1 can display various applications on the display. The communication device 1 is installed on furniture or the like, or is hung on a wall or the like, for example. The communication device 1 is connected to a public line network or the Internet network by wireless communication, and can communicate with other devices. In the present embodiment, it is assumed that the communication device 1 performs communication via a wireless LAN.

  As shown in FIG. 1, the communication device 1 has a substantially rectangular shape in front view with the left-right direction as a longitudinal direction, and includes a display 11 at a substantially center. A touch panel 12 (see FIG. 2) is provided on the front surface of the display 11. The user can input an instruction to the communication device 1 by touching the touch panel 12 while visually recognizing various information displayed on the display 11. The communication device 1 includes an antenna 13 for performing communication via a wireless LAN on the upper left side of the display 11 and inside the communication device 1. The communication device 1 is driven by power supplied from a built-in battery 34 (see FIG. 2) or power supplied by an AC power supply via an AC adapter (not shown).

  The electrical configuration of the communication device 1 will be described with reference to FIGS. As illustrated in FIG. 2, the communication device 1 includes a CPU 21, a ROM 22, a RAM 23, and a flash memory 24. The CPU 21 manages various control processes of the communication device 1. The CPU 21 is electrically connected to the ROM 22, RAM 23, and flash memory 24. The CPU 21 can access storage areas of the ROM 22, RAM 23, and flash memory 24.

  The ROM 22 includes at least a program storage area 221. The program storage area 221 stores program data necessary for the CPU 21 to execute various processes.

  The RAM 23 includes at least a group storage area 231. The group storage area 231 stores a group data table 54 (to be described later) (hereinafter referred to as a group DT54) or a group set in the process of S126 to be described later.

  As shown in FIG. 3, the flash memory 24 includes a use count data table storage area 241, a group number data table storage area 242, a weighted data table storage area 243, a recommunication start time storage area 244, and a master slave setting storage area 245. At least.

  The use count data table storage area 241 stores a use count data table 51 (hereinafter referred to as a use count DT51), which will be described later. The group number data table storage area 242 stores a group number data table 52 (hereinafter referred to as a group number DT52) which will be described later. The weighting data table storage area 243 stores a weighting data table 53 (hereinafter referred to as weighting DT53) which will be described later. The re-communication start time storage area 244 stores the re-communication start time set by the process of S129 in FIG. The master-slave setting storage area 245 stores data indicating a master device or data indicating a slave device set by the processing of S303 and the processing of S304 (see FIG. 14) in a later-described modification. Is done.

  As shown in FIG. 2, the communication device 1 includes an antenna 13 that performs communication by connecting to a public line network or the Internet network by wireless communication. The communication device 1 also includes a communication control unit 32 that controls drive control for performing wireless communication. The communication control unit 32 can switch between a transmission mode for transmitting communication data and a reception mode for detecting received signal strength (RSSI), receiving communication data, and the like. The CPU 21 can transmit and receive communication data via the public line network or the Internet network by wireless communication via the antenna 13 and the communication control unit 32. Further, the CPU 21 can detect the received signal strength via the antenna 13 and the communication control unit 32.

  The communication device 1 includes a display 11. The CPU 21 can display a desired image on the display 11. The communication device 1 includes a touch panel 12 into which an instruction from a user is input. The CPU 21 can recognize a user instruction input via the touch panel 12.

  A communication device 1 and a timer 33 are provided. The CPU 21 can measure time using the timer 33. The communication device 1 includes a battery 34 and a power control unit 35 that supplies power supplied from the battery 34 to other circuits. The above-described CPU 21 and other various devices are driven by power supplied from the battery 34 via the power supply control unit 35. The communication device 1 is connected to an AC adapter (not shown) and includes a jack for supplying power from the AC power source to the communication device 1, but is not shown. The communication device 1 can also be driven by power supplied from an AC power source.

  Next, a communication method of the communication device 1 according to the present embodiment will be described. This communication method is an example. The communication device 1 can perform communication via a wireless LAN. The frequency band of the wireless LAN is 2400 MHz to 2500 MHz. There are 14 channels in the frequency band of 2400 MHz to 2500 MHz. These 14 channels are called ch1 to ch14 in order from the channel with the lowest frequency. Each channel is assigned a band of a predetermined frequency width, and the center of the frequency width is referred to as a center frequency. When performing communication using a wireless LAN, a communication apparatus performs communication using a pseudo-random code in the frequency range assigned to each channel. That is, a device that performs communication performs communication by a so-called direct spread spectrum method.

  The center frequency of ch1 is 2412 MHz, and the center frequency of ch2 is 2417 MHz. Similarly, ch3 is 2422 MHz, ch4 is 2427 MHz, ch5 is 2432 MHz, ch6 is 2437 MHz, ch7 is 2442 MHz, ch8 is 2447 MHz, ch9 is 2452 MHz, ch10 is 2457 MHz, ch11 is 2462 MHz, ch12 is 2467 MHz, ch13 is 2472 MHz, ch14 is 2484 MHz.

  Next, various data tables 51 to 53 will be described with reference to FIGS. Information registered in various data tables can be arbitrarily set by the user. In addition, all the numerical values used in description of the various data tables 51-53 are illustrations.

  First, an example of the usage count DT51 will be described with reference to FIG. The use count DT51 is stored in the use count data table storage area 241 (see FIG. 3). In an environment where the communication device 1 is installed, there are devices that perform a plurality of communications. And the apparatus which performs several communication is communicating using a channel. The number of times of use DT51 represents the number of times (hereinafter referred to as the number of times of use) that each channel for each time is used by a device that performs a plurality of communications other than the communication device 1 (hereinafter referred to as other devices).

  In the description of the time in the following description, for example, 8:30 is represented as “8:30”. Further, the time when the number of uses is measured is represented by “T”. The number of times of use of each channel is measured a plurality of times a day, but FIG. 4 shows only the number of times of use measured during the time between 8: 30 ≦ T <10:30. Yes.

  The communication device 1 measures whether or not each channel is used by another device every time. And the measured result is divided | segmented for every measured time, and it memorize | stores in use frequency DT51. In the use count DT51, measurement results for the past 10 times are registered. The measurement results for the past 10 times are the results measured over several days (for example, 10 days). For example, in FIG. 4, the number of uses is “1” for ch1 at 9: 00 ≦ T <9:10. This indicates that ch1 has been used once by another device as a result of the past 10 measurements. In ch4 at 9: 50 ≦ T <10:00, the number of uses is “10”. This indicates that ch4 has been used 10 times by another device as a result of the past 10 measurements.

  In order to create the use count DT51, the communication device 1 scans ch1 to ch14 a plurality of times a day, and updates and stores the use count DT51. For example, in the case where the main process (see FIGS. 7 and 8) is executed, the result of the usage status of each channel measured in the main process in the process of S115 and the process of S120 (see FIG. 8) described later is used. It is registered in the use count DT51 and updated and stored. Even when the main processing is not executed, each channel is performed by performing the same processing as S112, S113, S114, S115, and S120 in the main processing described later for each of ch1 to ch14 a plurality of times a day. The result of the usage status is registered in the usage count DT51 and updated and stored.

  As shown in FIG. 4, in the usage count DT51, the time is 8: 30 ≦ T <9:00, 9: 00 ≦ T <9:10, 9: 10 ≦ T <9:20, 9: 20 ≦ T. <9:30, 9: 30 ≦ T <9:40, 9: 40 ≦ T <9:50, 9: 50 ≦ T <10:00, and 10: 00 ≦ T <10:30 .

  There are a time that is divided at intervals of 30 minutes such as 8: 30 ≦ T <9:00 and a time that is divided at intervals of 10 minutes such as 9: 00 ≦ T <9:10. When the usage status of each channel is normal, specifically, when the total of the past 10 usage counts of all channels is 80 times or less in 30 minutes, they are divided at intervals of 30 minutes. Further, when the usage status of each channel is congested, specifically, when the total of the past 10 usage counts of all channels is 80 times or more in 30 minutes, it is not an interval of 30 minutes, but 10 Divided into minute intervals. That is, when the communication status is normal, the time is divided at intervals of 30 minutes, and when the communication status is congested, the time is divided at intervals of 10 minutes. When the communication status for 30 minutes is congested, for example, when communication is concentrated only in 10 minutes out of 30 minutes, it is possible to communicate in the other 20 minutes even though communication is possible. There is a risk that it cannot be determined. For this reason, it is easy to determine a usable channel by dividing time into 10 minutes shorter than 30 minutes. In the usage count DT51, data indicating “normal” and “congested” which are communication states are associated with each other every 30 minutes.

  As shown in FIG. 4, when 8: 30 ≦ T <9:00, the number of times each channel is used is 2, 4, 4, 5, 4, 4, 0, 5, 1, 2 in the order of ch1 to ch14. , 5, 4, 6, 6. When 9: 00 ≦ T <9:10, the number of times each channel is used is 1, 4, 9, 1, 10, 9, 1, 5, 1, 1, 1, 8, 2, 2 in the order of ch1 to ch14. Nine. The other times are also stored as shown in FIG. In the time of 8: 30 ≦ T <9:00 and 10: 00 ≦ T <10:30, data indicating the communication status “normal” is associated. In addition, in the case of 9: 00 ≦ T <9:30 and 9: 30 ≦ T <10:00, data indicating the communication status “when busy” is associated.

  Next, an example of the group number DT52 will be described with reference to FIG. The group number DT52 is stored in the group number data table storage area 242 (see FIG. 3). The group number data table storage area 242 is referred to in S106 (see FIG. 7) of the main process which will be described later, and a group DT54 (see FIG. 9) which will be described later is created.

  As shown in FIG. 5, the communication status and the number of groups are registered in association with the number of groups DT52. The communication status is divided into a busy time and a normal time. The column for the time of congestion is referred to when the number of groups DT52 is used in the time associated with the data indicating the use status “when congested” in the use count DT51 (see FIG. 4). The normal column is referred to when the number of groups DT52 is used in the time associated with the data indicating the usage status “normal” in the usage count DT51.

  In FIG. 5, the communication status “congested” is associated with the number of groups “4”. The communication status “normal” is associated with the number of groups “2”. The number of groups represents the number of groups created when performing grouping in the process of S106 (see FIG. 7). Details of the grouping in the process of S106 will be described later.

  Next, an example of the weighting DT53 will be described with reference to FIG. The weighting DT53 is stored in the weighting data table storage area 243 (see FIG. 3). As shown in FIG. 6, the first to fifth conditions and the weights are associated with the weighting DT53. The weight represents a kind of priority. The higher the number, the higher the priority. The weighting DT53 is used in the processing of S109 (see FIG. 7) of the main processing described later, and is reflected in the scan order determined in the processing of S110 (see FIG. 8). Details of the processing of S109 and S110 will be described later.

  In the weighting DT53, the weight “5” is associated with the first condition. A weight “4” is associated with the second condition. A weight “3” is associated with the third condition. The fourth condition is associated with the weight “2”. The fifth condition is associated with the weight “1”.

  Hereinafter, the contents of the first to fifth conditions will be described. The contents of the first to fifth conditions are set in advance and registered in the weighting DT53. In addition, about the content of 1st-5th conditions, illustration in FIG. 6 is abbreviate | omitted. The content of the first condition is “a channel in which the number of times of use of both adjacent channels is three or less”. In other words, it is a channel that has a high possibility that the adjacent channels are not used. If the adjacent channels are not used, there is no radio wave when other devices communicate with each other on the adjacent channels. For this reason, it is hard to receive the influence of the electromagnetic wave at the time of another apparatus communicating, communication quality becomes favorable, and it becomes difficult to give radio wave interference also to another communication apparatus. For this reason, it is possible to give priority to a channel with high communication quality by giving a weight to the first condition.

  The content of the second condition is “a channel in which one of the adjacent channels is used three times or less”. In this case, it is highly likely that one of the adjacent channels is not used. For this reason, there is a high possibility that there is no radio wave when another device performs communication in either one of the adjacent channels, the communication quality is good, and radio interference occurs in other communication devices. It becomes difficult to give. For this reason, it is possible to give priority to a channel with high communication quality by giving a weight to the second condition.

  The contents of the third condition are “channels that are continued for 30 minutes before and after for 3 or less times”. That is, it is a channel that is not likely to be used for 30 minutes before and after. Such a channel is likely not being used at the current time. For this reason, by giving a weight to the third condition, it is possible to give priority to a channel that is not likely to be used.

  The content of the fourth condition is “a channel that is 20 MHz or more away from the maximum frequency and the minimum frequency in the frequency band in which the center frequency can be communicated”. In the present embodiment, there are a plurality of channels in the range of 2400 MHz to 2500 MHz, which is a wireless LAN standard. The range of 2400 MHz to 2500 MHz is determined by the standard. However, frequencies lower than 2400 MHz and frequencies higher than 2500 MHz are not wireless LAN standards. For this reason, there is a possibility that unnecessary radio waves from various other devices are flying around, and the communication quality may be deteriorated by the influence of the radio waves. For this reason, by selecting a channel that is 20 MHz or more away from the maximum frequency and the minimum frequency, it is possible to avoid the influence of radio waves from various other devices, and to maintain good communication quality. Can do. For this reason, by giving a weight to the fourth condition, priority can be given to a channel that can maintain good communication quality.

  The content of the fifth condition is “a channel in which the number of times of use in the same time zone as the current time zone is 3 or less”. That is, it is a channel that is not likely to be used at the current time. By giving a weight to the fifth condition, it is possible to give priority to a channel that is not likely to be used. The number of times of use “3 times” in the first to fifth conditions corresponds to the first frequency of the present invention and can be arbitrarily changed. Moreover, it is not necessary to make the value of the first frequency the same in the first to fifth conditions.

  Next, main processing performed by the communication device 1 according to the present embodiment will be described with reference to flowcharts shown in FIGS. The main process is executed by the CPU 21 in accordance with a program stored in the program storage area 221 of the ROM 22.

  As shown in FIG. 7, the CPU 21 initializes various data and resets various parameters and the like (S101). Next, the CPU 21 determines whether or not an instruction to start communication is input from the user via the touch panel 12 (see FIG. 2) (S102). When the CPU 21 determines that the communication start instruction has not been input (S102: NO), the re-communication start time set by the CPU 21 in the process of S129 (described later) (hereinafter, “re-communication start time”). It is determined whether or not (S103). The re-communication start time is a time that is set by the CPU 21 and stored in the re-communication start time storage area 244 in the process of S129 (described later) when the channel is congested and communication data is not transmitted. If the CPU 21 determines that the recommunication start time stored in the recommunication start time storage area 244 is not reached (S103: NO), the CPU 21 returns to the process of S102 and repeats the process.

  If the CPU 21 determines that the re-communication start time has come (S103: YES), the CPU 21 refers to the use count DT51 (see FIG. 4), and the use count is a predetermined use count (in the same time zone as the current time). Hereinafter, it is referred to as a predetermined number of times of use.) By identifying the following channels, usable channels are estimated (S104). The predetermined number of times of use is, for example, 80% of the number of times of measurement when creating the number of times of use DT51, that is, 8 times when the number of times of measurement is 10. Note that the CPU 21 also performs the process of S104 when it is determined in the process of S102 that an instruction to start communication is input by the user (S102: YES).

  The CPU 21 determines whether there is a channel estimated to be a usable channel in the process of S104 (S105). When the CPU 21 determines that there is a channel estimated to be a usable channel (S105: YES), the CPU 21 performs grouping (S106). The CPU 21 refers to the group number DT52 (see FIG. 5) stored in the group number data table storage area 242, and determines the number of groups (S106). Then, the CPU 21 assigns the usable channels estimated in the process of S104 to the number of groups corresponding to the determined number of groups, creates a group DT54 (see FIG. 9, described later), and stores it in the group storage area 231. (S106). The grouping method will be described later with a specific example.

  For example, it is assumed that the current time is 9:00 and the predetermined number of times of use is 80% of the number of times of measurement. That is, in the use count DT51 (see FIG. 4), the measurement count is 10 times, and therefore the predetermined use count is 8 times. In this case, if the CPU 21 determines that an instruction to start communication is input by the user (S102: YES), the CPU 21 estimates an available channel (S104). The CPU 21 refers to the use count DT51 (see FIG. 4) and refers to the use count of each channel in the same time zone as the current time 9:00 (S104). As shown in FIG. 4, the channels in which the number of uses in 9: 00 ≦ T <9:10 is a predetermined number of 8 or less are ch1, ch2, ch4, ch7, ch8, ch9, ch10, ch11, ch12. , And ch13, the CPU 21 estimates that these are usable channels (S104).

  The CPU 21 determines that there is a channel estimated to be a usable channel in the process of S104 (S105: YES), and performs grouping (S106). As described above, the number of groups DT52 (see FIG. 5) is divided into a crowded time and a normal time, and the number of groups is associated with each. In the use count DT51 (see FIG. 4), 9: 00 ≦ T <9:10 including the same time as the current time 9:00 is a busy time. In the group number DT52 (see FIG. 5), since the number of groups corresponding to the congestion is “4”, the CPU 21 determines the number of groups as “4” (S106). Each of the four groups is divided by the number of uses. Let X be the number of uses. Here, for example, the CPU 21 associates a channel having the number of uses satisfying “0 ≦ X ≦ 3” with the first group, and associates a channel with the number of uses satisfying “3 <X ≦ 4” with the second group. . It is assumed that the CPU 21 associates a channel having the number of uses satisfying “4 <X ≦ 6” with the third group and associates a channel with the number of uses satisfying “6 <X ≦ 8” with the fourth group.

  In this case, the CPU 21 creates a group DT54 (see FIG. 9) and stores it in the group storage area 231 (S106). As shown in the group DT54 of FIG. 9, the CPU 21 associates ch1, ch4, ch7, ch9, ch10, ch11, and ch13 satisfying “0 ≦ X ≦ 3” with the first group, and with the second group, Associate ch2 that satisfies “3 <X ≦ 4”. The CPU 21 associates ch8 satisfying “4 <X ≦ 6” with the third group, and associates ch12 satisfying “6 <X ≦ 8” with the fourth group (S106).

  After performing grouping (S106), the CPU 21 determines a group to be scanned (S107). In the process of S107, the CPU 21 preferentially selects a group with a small number of uses from the groups created in the process of S106. This is because it is highly possible that a communicable channel can be found at an early stage by scanning a group with a small number of uses. When the CPU 21 creates a group in the process of S126 described later, the CPU 21 selects the group created in the process of S126. The CPU 21 executes the process of S107 every time it determines that there is an unselected group in the process of S117, which will be described later, but does not determine the group once determined.

  Next, the CPU 21 determines whether there is a channel having the same number of uses in the group determined in the process of S107 (S108). When the CPU 21 determines that there are channels having the same number of uses (S108: YES), the CPU 21 performs a priority order determination process (S109). The CPU 21 compares various conditions of channels with the same number of times of use, and ranks the channels so that priority is given to a channel with a higher communication quality or a channel with a higher possibility of not being used. Determine (S109). The CPU 21 performs the priority order determination process with reference to the weighting DT 53 (see FIG. 6), and details will be described later with a specific example.

  Next, as shown in FIG. 8, the CPU 21 determines the order of scanning (S110). Note that the CPU 21 also performs the process of S110 when it is determined in the process of S108 that there is no channel having the same number of uses (S108: NO). The CPU 21 determines the scan order in order from the channel with the smallest number of uses in the group determined in the process of S107 (S110). Further, the CPU 21 determines the scan order for the channels having the same number of times of use in the priority order determined in the process of S109.

  For example, an example where the current time is 9:00 will be described. When the CPU 21 performs grouping as in the above-described group DT54 shown in FIG. 9, the CPU 21 selects the first group that is a group that is used less frequently (S107). Next, in the first group, the number of uses in ch1, ch4, ch7, ch9, ch10, and ch11 is all “1” and is the same (see FIG. 4), so the CPU 21 has the same number of uses. It is determined that there is a channel (S108: YES), and priority order determination processing is performed (S109). The CPU 21 refers to the weighting DT 53 (see FIG. 6), calculates the total weight, which is the sum of the weights corresponding to the channel status, for each channel, and determines the priority in order of the channels with the largest total weight ( S109).

  Among the ch1, ch4, ch7, ch9, ch10, and ch11, the channel that satisfies the first condition “channel where the number of times of use of both adjacent channels is three or less” is ch10. This is because both the channels ch9 and ch11 that are adjacent to ch10 are used three times or less (see FIG. 4). For this reason, the CPU 21 adds the weight “5” for ch10. Channels that satisfy the condition of the second condition “a channel in which one of the adjacent channels is used three times or less” are ch9 and ch11. This is because the number of uses of ch10 adjacent to ch9 is three or less and the number of uses of ch8 is greater than three (see FIG. 4). In addition, the number of uses of ch10 adjacent to ch11 is three or less, and the number of uses of ch11 is greater than three (see FIG. 4). Therefore, the CPU 21 adds the weight “4” for ch9 and ch11.

  The channels satisfying the condition of the third condition, “channels that continue for 30 minutes before and after for three minutes or less” are ch1, ch7, ch9, and ch10 (see FIG. 4). Therefore, the CPU 21 adds the weight “3” for ch1, ch7, ch9, and ch10. Channels that satisfy the fourth condition, “channels whose center frequencies are 20 MHz or more away from the maximum frequency and the minimum frequency in the communicable frequency band” are ch4, ch7, ch9, ch10, and ch11. . As described above, the frequency band of the wireless LAN in this embodiment is 2400 MHz to 2500 MHz. That is, the maximum frequency is 2500 MHz and the minimum frequency is 2400 MHz. A channel whose center frequency is 20 MHz or more away from the maximum frequency and the minimum frequency is a channel whose center frequency is between 2420 MHz and 2480 Mz. The center frequencies of ch4, ch7, ch9, ch10, and ch11 are 2437 MHz, 2442 MHz, 2452 MHz, 2457 MHz, and 2462 MHz, respectively. For this reason, the fourth condition is satisfied. The CPU 21 adds the weight “2” to each of ch4, ch7, ch9, ch10, and ch11.

  Further, channels satisfying the condition of the fifth condition “a channel in which the number of times of use in the same time zone as the current time zone is 3 or less” are ch1, ch4, ch7, ch9, ch10, and ch11 (FIG. 4). reference). The CPU 21 adds a weight “1” to each of ch1, ch4, ch7, ch9, ch10, and ch11.

  As described above, the CPU 21 adds weights to the respective channels. Since the weights “1” and “3” are added to ch1, the total weight is “4”. Since the weights “1” and “2” are added to ch4, the total weight is “3”. Since the weights “1”, “2”, and “3” are added to ch7, the total weight is “6”. Since the weights “1”, “2”, “3”, and “4” are added to ch9, the total weight is “10”. Since the weights “1”, “2”, “3”, and “5” are added to ch10, the total weight is “11”. Since the weights “1”, “2”, and “4” are added to ch11, the total weight is “7”. As a result, ch10, ch9, ch11, ch7, ch1, and ch4 are assigned in the order of the channels with the largest total weight. Then, the CPU 21 determines the priority order in this order (S109).

  Next, the CPU 21 determines the order of scanning (S110). The CPU 21 determines the scan order in the order of the channels with the smallest number of uses in the group determined in the process of S107. Among the groups determined by the CPU 21 in the process of S107, the channels with the least number of uses are ch1, ch4, ch7, ch9, ch10, and ch11 that have a use count of “1”. The CPU 21 determines the scan order for these channels in the order of ch10, ch9, ch11, ch7, ch1, ch4, which is the order determined in the process of S109 (S110).

  The channel with the next smallest number of uses is ch13, which is used twice (see FIG. 4). Therefore, the CPU 21 determines that the scan order is ch10, ch9, ch11, ch7, ch1, ch4, ch13 (S110).

  After determining the scan order (S110), the CPU 21 then controls the communication control unit 32 and sets the communication control unit 32 to the reception mode (S111). The reception mode is a state in which the CPU 21 can detect radio waves. Next, the CPU 21 controls the communication control unit 32 to set a channel and start measurement of received signal strength (S112). The channel setting is to make the received signal intensity of the frequency of the desired channel measurable so that the CPU 21 detects the usage status of the desired channel. Whenever the CPU 21 determines that there is a channel that has not been scanned in the group in the process of S116 (described later), the CPU 21 executes the process of S112, sets the channels in the scan order determined in the process of S110, Start measurement of received signal strength.

  Next, the CPU 21 measures the received signal strength for a predetermined time (S113). The predetermined time is, for example, 0.1 seconds. Next, the CPU 21 determines whether or not the state in which the received signal strength is smaller than the predetermined threshold has continued for the predetermined time when the received signal strength is measured in the process of S113 (S114). The predetermined threshold is provided to determine whether or not the channel is being used by another device. For example, the predetermined threshold is a signal received by the antenna 13 and input to the CPU 21 via the communication control unit 32. It is a voltage value. For example, when the CPU 21 is driven at 3.0V, the predetermined threshold is 0.6V, which is 20% of 3.0V. The provision of the predetermined threshold value prevents the CPU 21 from erroneously detecting noise such as white noise and erroneously determining that the channel is being used by another device. When another device is not using the channel, the state where the received signal strength is smaller than a predetermined threshold value continues for a predetermined time. On the other hand, when another device uses the channel, there is a timing at which the received signal strength becomes equal to or higher than a predetermined threshold during a predetermined time. That is, the CPU 21 determines whether or not the channel set in the process of S112 is a usable channel (S114).

  When other devices are directly communicating by spread spectrum, communication is performed using a pseudo-random code within the same channel. For this reason, if the CPU 21 measures the received signal strength for a short time (for example, 0.005 seconds) in the process of S113, the radio waves of other devices that are communicating by the generation of a pseudo-random code are transmitted. May not be detected. Therefore, the CPU 21 performs measurement for a predetermined time (S113), and if the predetermined threshold value is exceeded even once during that time, it is determined that the channel is being used by another device (S114: NO). .

  When the state where the received signal strength is smaller than the predetermined threshold does not continue for the predetermined time when the CPU 21 measured the received signal strength in the process of S113, the channel is being used by another device, so the CPU 21 Is not a usable channel (S114: NO). Subsequently, the CPU 21 registers this channel in the use count DT51 (see FIG. 4) as a channel used by another device, and updates and stores the use count DT51 (see FIG. 4) (S115). That is, the CPU 21 updates the past 10 use times in the use number DT51 (S115).

  Next, the CPU 21 determines whether there is a channel that has not been scanned in the group determined in the process of S107 (S116). When the CPU 21 determines that there is a channel that has not been scanned in the group determined in the process of S107 (S116: YES), the CPU 21 returns to the process of S112, changes the channel, and continues the scan. If the CPU 21 determines that there is no channel that has not been scanned in the group determined in S107 (S116: NO), the CPU 21 determines whether there is a group that has not been scanned (S117). ). If the CPU 21 determines that there is a group that has not been scanned (S117: YES), then it returns to S107 and repeats the process (S107). That is, since all the channels in the group determined in the process of S107 are used by other devices (S116: NO), if there is a group for which scanning has not been performed (S117: YES), the group is newly added. A determination is made (S107) and channel scanning continues.

  If the CPU 21 determines that there is no channel that has not been scanned (S117: NO), the channels of all groups are used by other devices. For this reason, the CPU 21 displays on the display 11 that data could not be transmitted because there is no usable channel, and ends the scan (S118). For example, the CPU 21 displays a display such as “data could not be transmitted” on the display 11. Next, the CPU 21 returns to the process of S102 and repeats the process.

  In the process of S114, when the state where the received signal strength is smaller than the predetermined threshold value continues for a predetermined time, the CPU 21 determines that the channel is usable (S114: YES), and determines the usable channel. Then, it is determined as a channel for communication (S119). Next, the CPU 21 registers the channel determined to be usable in the process of S114 in the usage count DT51 as a channel that has not been used by another device, and stores the usage count DT51 (see FIG. 4). The update is stored (S120). That is, the CPU 21 updates the past 10 use counts in the use count DT51.

  Next, the CPU 21 starts communication and transmits data (S121). In the process of S121, the CPU 21 controls the communication control unit 32 and sets the communication control unit 32 to the transmission mode. The transmission mode is a state in which the CPU 21 can transmit data. Then, the CPU 21 transmits data. After transmitting the data, the CPU 21 cancels the transmission mode setting and ends the communication (S122). Next, the CPU 21 returns to the process of S102 and repeats the process.

  For example, it is assumed that the predetermined time for measurement in the process of S113 is 0.1 second, and the threshold value of the received signal strength in the process of S114 is 0.6V. As described above, when the CPU 21 determines that the scanning order is ch10, ch9, ch11, ch7, ch1, ch4, ch13 (S110), the CPU 21 then receives the communication control unit 32. The mode is set (S111). Next, the CPU 21 starts measurement of received signal strength for ch10 that first executes a scan (S112). The CPU 21 continues the measurement of the received signal strength for a predetermined time of 0.1 seconds (S113), and the received signal strength is measured in the process of S113 when the received signal strength is smaller than the predetermined threshold value of 0.6V. It is determined whether or not it has continued for the predetermined time (S114).

  Here, it is assumed that ch10 is in use and the CPU 21 detects a received signal strength of 0.6 V or more in 0.1 seconds. In this case, since the state where the received signal strength is smaller than 0.6 V does not continue for 0.1 seconds when the received signal strength is measured in the process of S113, the CPU 21 determines that the channel is not usable (S114). : NO). Subsequently, the CPU 21 registers the use count DT51 (see FIG. 4) and updates and stores the use count DT51, assuming that ch10 is a channel used by another device (S115). That is, the CPU 21 updates the past 10 use counts of ch10 in the use count DT51. Next, the CPU 21 determines that there is a channel that has not been scanned in the first group determined in the process of S107 (S116: YES), selects ch9 (S112), and continues the scan.

  When ch9, ch11, ch7, ch1, ch4, and ch13 are all used by other devices, the CPU 21 repeats the processing of S112 to S116 for ch9, ch11, ch7, ch1, ch4, and ch13, and then first It is determined that there is no channel that has not been scanned in the group (S116: NO). And since CPU21 is not performing the scan about the channel of the 2nd-the 4th group (refer to Drawing 9), it judges that there is a channel which is not performing a scan (S117: YES), and sets the 2nd group. A new group to be scanned is determined (S107: NO), and the process is repeated.

  If all the channels of the second to fourth groups (see FIG. 9) are used, the CPU 21 does not have any channels that have not been scanned after scanning the channels of the second to fourth groups. (S117: NO). Next, the CPU 21 displays a display such as “data could not be transmitted” on the display 11 (S118). Next, the CPU 21 returns to the process of S102 and repeats the process.

  On the other hand, for example, when the first group of ch9 is not used by another device, the state where the received signal strength is less than 0.6 V continues for 0.1 second, so the CPU 21 is a channel that can use ch9. It is determined that there is a channel (S114: YES), and ch9 that is a usable channel is determined as a channel for communication (S119). Next, the CPU 21 registers ch9 in the use count DT51 as a channel that has not been used by another device, and updates and stores the use count DT51 (see FIG. 4) (S120). That is, the CPU 21 updates the past 10 use counts of ch9 in the use count DT51.

  Next, the CPU 21 sets the communication control unit 32 to the transmission mode, and transmits data using ch9 (S121). Next, the CPU 21 cancels the transmission mode setting and ends the communication (S122). Next, the CPU 21 returns to the process of S102 and repeats the process.

  Next, in the process of S104, a case where there is no channel that is estimated to be usable when the CPU 21 estimates a usable channel (S105: NO) will be described. In this case, the CPU 21 displays on the display 11 a comment that it is unlikely that data can be transmitted and an input button for allowing the user to input an instruction (S123). An example of comments and input buttons displayed on the display 11 is shown in FIG. As shown in FIG. 10, in the center of the display 11, as a comment, “There is a possibility that data cannot be transmitted due to communication congestion. Please enter an instruction.” Is displayed. This comment can inform the user that there is a high possibility that there is no usable channel. Below the comment, a transmission work continuation button 111 for starting execution of scanning and continuing the data transmission work, and an automatic transmission button 112 for saving data to be transmitted and automatically transmitting it later A cancel button 113 for canceling data transmission is displayed.

  Next, the CPU 21 determines whether or not an instruction from the user has been input by detecting that the touch panel 12 at a position corresponding to the input button displayed on the display 11 has been pressed by the user (S124). . When the CPU 21 determines that no instruction from the user has been input (S124: NO), the CPU 21 returns to the process of S124 and repeats the process. If the CPU 21 determines that an instruction from the user has been input (S124: YES), the CPU 21 determines whether the button pressed by the user in the process of S124 is the transmission work continuation button 111 (S125). ).

  When there is a high possibility that there is no usable channel, but the user desires to perform channel scanning, the user presses the transmission work continuation button 111. If the CPU 21 determines that the button pressed by the user is the transmission work continuation button 111 (S125: YES), the CPU 21 sets all the channels as one group and stores them in the group storage area 231 (S126). ). In the following description, the group set by the process of S126 is referred to as a fifth group. Next, the CPU 21 proceeds to the process of S107 and performs the process. That is, the CPU 21 determines the fifth group as a group for executing scanning (S107), and performs the processes of S107 to S122. As a result, even when there is a high possibility that there is no usable channel, a scan can be executed if there is an instruction from the user.

  When the CPU 21 determines that the button pressed by the user is not the transmission work continuation button 111 (S125: NO), the CPU 21 determines whether or not the button pressed by the user is the automatic transmission button 112. (S127). If the CPU 21 determines that the button pressed by the user is the automatic transmission button 112 (S127: YES), then, referring to the use count DT51 (see FIG. 4), there is an available channel. The estimated time is specified (S128). The CPU 21 refers to the number of use times DT51, and specifies a time during which a channel whose number of times of channel use is equal to or less than a predetermined number of times of use (for example, 8 times) after the time corresponding to the current time exists. The time estimated to have a usable channel is specified (S128).

  Next, the CPU 21 sets the time specified in the process of S128 as a recommunication start time, and stores it in the recommunication start time storage area 244 (S129). Next, the CPU 21 returns to the process of S102 and repeats the process. When the CPU 21 determines that the re-communication start time has come (S103: YES), the CPU 21 proceeds to the process of S104 and performs a process for performing communication. In this way, data is automatically transmitted.

  If the CPU 21 determines in the process of S127 that the button pressed by the user is not the automatic transmission button 112 (S127: NO), the cancel button 113 is pressed by the user, so the process of S102 is performed. Return and repeat the process.

  For example, it is assumed that the predetermined number of times of use is 8 and the current time is 9:40. In 9: 40 ≦ T <9:50 corresponding to the current time in the use count DT51 (see FIG. 4), the use count of all channels is more than 8. For this reason, the CPU 21 estimates that there is no usable channel (S104). Then, the CPU 21 determines that there is no channel estimated to be a usable channel (S105: NO) and, as shown in FIG. 10, a comment indicating that there is a low possibility of data transmission and an input button. A transmission work continuation button 111, an automatic transmission button 112, and a cancel button 113 are displayed on the display 11 (S123). Next, when the user presses the input button, the CPU 21 determines that an instruction from the user has been input (S124: YES), and determines whether the button pressed by the user is the transmission work continuation button 111 or not. Judgment is made (S125).

  When the CPU 21 determines that the button pressed by the user is the transmission work continuation button 111 (S125: YES), it sets all channels ch1 to ch14 as one fifth group, Store in the storage area 231 (S126). Next, the CPU 21 proceeds to the process of S107 and executes a channel scan.

  When the button pressed by the user is the automatic transmission button 112, the CPU 21 determines that the transmission work continuation button 111 is not pressed (S125: NO), and determines that the automatic transmission button 112 is pressed. (S127: YES). Next, the CPU 21 refers to the use count DT51 and estimates that there is a channel that can use 10: 00 ≦ T <10:30 in which there is a channel with the use count of 8 or less in the time after 9:40. Specified as time to be. Then, the CPU 21 sets the time 10: 00 ≦ T <10:30 specified in the process of S128 as the recommunication start time, and stores it in the recommunication start time storage area 244 (S129). Next, the CPU 21 returns to the process of S102 and repeats the process.

  When the CPU 21 determines that the time has elapsed and the time within the range of 10: 00 ≦ T <10:30 set as the re-communication start time, specifically 10:00, is determined (S103: YES) ), The CPU 21 proceeds to the process of S104 and repeats the process.

  As described above, the main processing of this embodiment is performed. According to the present embodiment, the CPU 21 estimates a usable channel by referring to the number of times each channel is used at the same time as the current time in the number of times used DT51 (S104), and determines the order of scanning. Yes. The number of uses registered in the number of uses DT51 indicates the results of channels used in the past in the environment where the communication device 1 is installed. In general, other devices are often fixed to a certain frequency band (channel) or scan according to a certain pattern to determine a channel to be used. For this reason, the number of uses DT51 shows a tendency of channels used by other devices at each time. Since the tendency of channels used by other devices appears in the usage count DT51, the CPU 21 can scan channels that are likely to be used at the current time by using the usage count DT51. Therefore, the channel for communication can be determined efficiently. In addition, it is possible to reduce the load on the CPU when scanning channels, and to reduce power consumption.

  Further, in the process of S110, the CPU 21 determines the order in which scans are executed in the order of the least number of past uses. For this reason, CPU21 can perform a scan in an order from the channel with high possibility of being usable in the present time, and can determine the channel which communicates efficiently.

  In the process of S109, the CPU 21 determines priorities by assigning weights to the first to fifth conditions. By assigning weights to the first to fifth conditions, scanning can be performed with priority on channels with high communication quality and channels that are not likely to be used. The weight value is an example, and the weight value may be changed. Further, it is not necessary to set weights for all of the first to fifth conditions. For example, only two of the first condition and the third condition may be weighted. In addition, weighting is an example, and weighting may not be performed. In this case, for example, the scan execution order is determined in the order of channels satisfying the first condition, channels satisfying the second condition, channels satisfying the third condition, channels satisfying the fourth condition, and channels satisfying the fifth condition. May be. Even in this case, scanning can be performed with priority given to channels with high communication quality or unused channels. As described above, at least one of the first to fifth conditions may be set to determine the priority order.

  In addition, the CPU 21 measures the received signal strength in the processes of S113 and S114, and determines that the channel is currently used if the received signal strength is equal to or greater than a predetermined threshold. That is, according to the present embodiment, it is possible to determine whether the channel is usable by referring to the received signal strength.

  Further, the CPU 21 estimates in the process of S104 that a channel having a predetermined number of times of use or less is a usable channel. If there is no channel estimated to be usable (S105: NO) and the user presses the cancel button 113 (S127: NO), the CPU 21 does not execute the scan. For this reason, the load on the CPU can be reduced and the power consumption can be reduced.

  In addition, this invention is not limited to said embodiment, A various change is possible. For example, although a wireless LAN has been described as an example, the present invention is not limited to this. Other communication methods may be used.

  Moreover, although the use frequency DT51 referred to only one type, it is not limited to this. For example, the usage count DT51 may be created and referred to on holidays, every day of the week, every month, and every season.

  Moreover, although the group number DT52 divided the group number at the time of congestion and a normal time, it is not limited to this. For example, the number of groups may be divided according to holidays, every day of the week, every month, and every season.

  The number of uses corresponds to the “use frequency” of the present invention, but the “use frequency” of the present invention is not limited to the number of uses. For example, it may be a ratio of the number of times used by another device to the number of times the scan is executed. Further, for example, it may be an average value of the number of times of use per minute, which is a result of dividing the total number of times of use of each channel for 30 minutes by 30 minutes. Similarly, the “first frequency” and “second frequency” of the present invention are not limited to the number of times.

  Further, in the processes of S113 to S114, the received signal strength is measured and it is determined whether or not the channel is usable. However, the present invention is not limited to this. For example, it may be determined whether the channel is usable by measuring a baseband signal.

  Further, in the process of S123, the comment indicating that the possibility of data transmission is low and the input button are displayed on the display 11. However, the present invention is not limited to this. For example, the input button may not be displayed. In this case, the transmission may be canceled without being accepted by the user, or may be automatically retransmitted later.

  Further, in the process of S123, instead of displaying a comment indicating that there is a low possibility that data can be transmitted, the graph 60 shown in FIG. The graph 60 will be described. The graph 60 represents the usage status of the channel for each time as a histogram. The horizontal axis is time, and the vertical axis is the total number of times ch1 to ch14 are used. The graph 60 represents the number of times of use every 30 minutes as a histogram, but is not limited to this. For example, the graph 60 may be represented at intervals of 10 minutes during congestion and at intervals of 30 minutes during normal times.

  The graph 60 is created from data for 24 hours in the use count DT51. For example, in the use count DT51 (see FIG. 4), the total use count of ch1 to ch14 of 8: 30 ≦ T <9:00 is 52 times. The total number of uses of ch1 to ch14 with 9: 00 ≦ T <9:30 is 189 times. In addition, the total number of uses of ch1 to ch14 with 9: 30 ≦ T <10:00 is 340 times. The total number of times of use of ch1 to ch14 with 10: 00 ≦ T <10:30 is 64 times. In the graph 60, the number of times of use is displayed as a histogram. Since the graph 60 represents the past number of times of use, it can be used as a prediction graph of the degree of congestion of current and near future communications. The user can know the degree of communication congestion with reference to the graph 60. Further, when displaying the graph 60 on the display 11, the color of the portion of the graph corresponding to the current time may be changed or blinked. Thereby, the user can confirm at a glance the prediction of the degree of communication congestion at the current time. Also, the color of the graph may be changed according to the channel usage status.

  Further, when there are a plurality of communication devices of the same type in the environment where the communication device 1 is installed, a master / slave process, which is a type of communication protocol model, may be performed. Hereinafter, a case where master / slave processing is performed will be described. When there are a plurality of communication devices of the same type under the same usage environment, the number of uses DT51 (see FIG. 4) is the same in the plurality of communication devices. For this reason, there is a possibility that a plurality of communication devices simultaneously select the same channel. In order to avoid this state, a communication device that attempts to start communication at the same time temporarily waits and starts communication again. At this time, the master device starts communication before the slave device. In the following description, in the master / slave process, the standby time data table 55 will be described first, then the process performed at the access point (not shown) will be described, and then the process performed at the communication device 1 will be described. To do.

  The standby time data table 55 (hereinafter referred to as standby time DT55) will be described. The standby time DT55 is stored in the flash memory 24 (see FIG. 2). The range of the standby time is represented by time T2, and the microsecond of time unit is represented by “μS”. As shown in FIG. 15, the standby time DT55 is divided into columns of a master device and a slave device. The column of the master device is associated with a waiting time of 10 μS ≦ T2 ≦ 50 μS. The slave device column is associated with a waiting time of 50 μS <T2 ≦ 200 μS. The standby time DT55 is referred to in the processing of S405 and S406 of the communication device 1 (see FIG. 15, described later), and details will be described later.

  Next, an access point will be described. When communicating via a wireless LAN, the communication device communicates via an access point (not shown). The access point is provided between the communication device 1 and the Internet network or public line network. When there are a plurality of communication devices of the same type under the same use environment, the same access point is used. When the communication device performs communication, the access point transmits an acknowledgment signal (ACK), which is a signal indicating that communication is permitted, to the communication device. Hereinafter, access point processing that is processing performed by the CPU of the access point will be described.

  As shown in FIG. 13, in the access point process, first, a communication inquiry signal is received. When starting communication, the CPU 21 of the communication device 1 accesses a communication inquiry signal, which is a signal for making an inquiry to the access point, in order to start communication in the process of S401 (see FIG. 15, described later). Send to point. In the process of S201, the CPU of the access point determines whether or not a communication inquiry signal transmitted from the communication device 1 and another communication device has been received (S201). When the communication question signal is not received (S201: NO), the CPU of the access point then repeats the process of S201.

  When the communication question signal is received (S201: YES), the CPU of the access point determines whether or not the received communication question signal can be analyzed (S202). When a plurality of communication devices try to start communication at the same timing, each communication device transmits a communication question signal at the same time. Therefore, the communication question signals collide with each other, and the communication question signal cannot be analyzed by the CPU of the access point. It becomes a state. When a plurality of communication devices are not trying to start communication at the same timing, the communication question signals do not collide with each other, so that the communication question signals can be analyzed by the CPU of the access point.

  When the CPU of the access point determines that the communication question signal received in the process of S201 can be analyzed (S202: YES), it indicates that communication is permitted to the communication device that has transmitted the communication question signal. An acknowledgment signal (ACK), which is a signal indicating this, is transmitted (S203). If the communication inquiry signal can be analyzed, the CPU of the access point can identify the communication device that has transmitted the communication inquiry signal. The CPU of the access point transmits an acknowledgment signal to the identified communication device. When the confirmation response signal is transmitted to the communication device 1, the confirmation response signal is received in the process of S402 of the CPU 21 of the communication device 1 (see FIG. 15). Next, the CPU of the access point returns to S201 and repeats the process.

  When the CPU of the access point determines that the communication inquiry signal received in the process of S201 cannot be analyzed (S202: NO), it does not respond to the communication device and does not transmit the confirmation response signal (S204). This is because the communication question signal cannot be analyzed, and thus the CPU of the access point cannot identify the communication device that has transmitted the communication question signal. Next, the process returns to S201 and is repeated.

  Next, a master / slave setting process executed by the CPU 21 of the communication device 1 will be described with reference to FIG. The master / slave setting process is a process of setting each communication device as a master device and a slave device when there are a plurality of communication devices of the same type. Furthermore, when set as a slave device, data of the number of use times DT51 stored in the master device can be received and stored. The master / slave setting process is performed, for example, when the communication apparatus 1 is installed in a new environment and the communication apparatus 1 is powered on, or is performed every few days.

  In the master / slave setting process shown in FIG. 14, the CPU 21 detects whether or not there is another communication device of the same type in the installation environment of the communication device 1 (S301). The detection in the process of S301 detects, for example, a pseudo-random code pattern unique to a communication device when performing direct spectrum spreading, a signal for specifying the type of communication device incorporated in a signal at the time of communication, and the like. Is done by. Note that when there is another communication device of the same type, the user may set the communication device 1 that there is another communication device.

  Next, the CPU 21 determines whether there is another communication device of the same type as a result of the detection in the process of S301 (S302). If there is no other communication device of the same type (S302: NO), the CPU 21 sets the communication device 1 as a master device by storing data indicating that it is a master device in the master slave setting storage area 245. (S303).

  If the CPU 21 determines in the process of S302 that another communication device of the same type exists (S302: YES), the CPU 21 communicates by storing data indicating that it is a slave device in the master-slave setting storage area 245. The device 1 is set as a slave device (S304). Next, the CPU 21 communicates with a communication device operating as a master device among other communication devices of the same type, and is transmitted from the master device. The use count DT51 stored in the master device (see FIG. 4). Is stored in the use count data table storage area 241 (S305). That is, the use count DT51 measured by the master device in the environment where the communication device 1 is newly installed is also stored in the communication device 1. As a result, the communication device 1 can obtain information on the status of communication in a new installation environment without performing measurement for creating the use count DT51 in the device itself. Therefore, even in a new environment, by using the use count DT51 measured by the master device, it is possible to efficiently detect a usable channel. When the process of S305 is performed, the CPU 21 ends the master / slave setting process.

  Next, a modification of the main process shown in FIGS. 7 and 8 in the case of the master / slave process will be described with reference to FIG. FIG. 15 is obtained by adding the processes of S401 to S406, which are unique processes in the case of the master / slave process, between the processes of S110 and S111 in the main process shown in FIGS. . In the following description, processes similar to those in FIGS. 7 and 8 are denoted by the same reference numerals, and detailed description thereof is omitted. 7 and 8 is the same in the case of the master / slave process, and therefore illustration and description thereof are omitted, and a modification of the process shown in FIG. Only certain FIG. 15 will be described.

  As shown in FIG. 15, when the CPU 21 determines the scan order in the process of S110, it then transmits a communication inquiry signal to the access point (S401). The communication inquiry signal is received in the process of S201 of the access point CPU (see FIG. 13). Next, the CPU 21 waits to receive an acknowledgment signal transmitted by the processing of S203 executed by the CPU of the access point (S402). The waiting time is, for example, 1 mS.

  Next, the CPU 21 determines whether or not an acknowledgment signal has been received in the process of S402 (S403). When the confirmation response signal is transmitted by the CPU 21 of the access point (S203 in FIG. 13), there is no other communication device that intends to start communication at the same time. On the other hand, when the confirmation response signal is not transmitted by the CPU 21 of the access point (the process of S204 in FIG. 13), there is another communication device that is trying to communicate at the same time (or communication due to the influence of the signal of another device). If an error occurs). That is, the CPU 21 can predict and determine whether or not another communication device is executing a scan by executing the process of S403. If the CPU 21 determines that the confirmation response signal has been received (S403: YES), the CPU 21 proceeds to S111 and executes a channel scan. This is because communication is permitted by the access point. Since the subsequent processing has already been described with reference to FIGS.

  If the CPU 21 determines that the confirmation response signal has not been received (S403: NO), then the CPU 21 determines whether or not the communication device 1 as its own device is a master device (S404). The CPU 21 determines whether or not the communication device 1 is the master device by referring to the data stored in the master / slave setting storage area 245 in the processing of S303 or S304 (see FIG. 14) (S404).

  When the CPU 21 determines that the communication device 1 is the master device (S404: YES), the CPU 21 stands by (S405). In the process of S405, the CPU 21 refers to the standby time of the master device stored in the standby time DT55 (see FIG. 12). Then, the standby time is determined within the range of the standby time associated with the master device column, and the system waits for the determined standby time (S405). The CPU 21 randomly determines the standby time within the standby time range in the standby time DT55 (S405). When the CPU 21 waits for the waiting time, it returns to S401 and repeats the process.

  For example, in the standby time DT55 (see FIG. 12), the standby time of the master device is 10 μS ≦ T2 ≦ 50 μS. The CPU 21 randomly determines a standby time between 10 μS ≦ T2 ≦ 50 μS and waits for the determined standby time (S405). For example, when the CPU 21 determines that the standby time is 25 μS, the CPU 21 waits for 25 μS, returns to the process of S401, and repeats the process. When the CPU 21 receives the confirmation response signal (403: YES), the CPU 21 proceeds to S111 and executes a channel scan.

  When the communication device 1 is a slave device, in the process of S404, the CPU 21 determines that the communication device 1 is not a master device (S404: NO), and performs standby (S406). In the process of S406, the CPU 21 refers to the standby time of the slave device stored in the standby time DT55. Then, the standby time is determined within the range of the standby time of the slave device, and waits for the determined standby time (S406). In addition, when determining the standby time, the CPU 21 determines at random within the range of the standby time (S406). When the CPU 21 waits for the standby time, the CPU 21 returns to the process of S401 and repeats the process.

  For example, in the standby time DT55, the standby time of the slave device is 50 μS <T2 ≦ 200 μS. The CPU 21 randomly determines the standby time between 50 μS <T2 ≦ 200 μS and waits for the determined standby time (S406). For example, when the CPU 21 determines the standby time to be 100 μS, the CPU 21 waits for 100 μS, returns to the process of S401, and repeats the process. When the CPU 21 receives the confirmation response signal (S403: YES), the CPU 21 proceeds to S111 and executes a channel scan.

  As described above, when there are a plurality of communication devices of the same type, a master / slave process, which is a type of communication protocol model, may be performed. When the CPU 21 determines that the confirmation response signal has been received (S403: YES), a channel scan is executed. In other words, since the scan is executed when the other communication device is not about to start communication, it is possible to prevent the scan timings of the communication device 1 and the other communication device from being the same. For this reason, it can prevent that the communication apparatus 1 and another communication apparatus select the same channel simultaneously.

  In the standby time DT55 (see FIG. 12), the standby time of the master device is set shorter than the standby time of the slave device. When the timing at which the communication device 1 tries to start communication with another communication device is the same, the CPU of the access point does not transmit an acknowledgment signal (S204, see FIG. 13). At this time, if the communication device 1 is a master device, the standby time is determined within the range of the standby time of the master device in the standby time DT55 and waits (S405). That is, the CPU 21 waits for a time shorter than the standby time of the slave device (S405), and transmits a communication inquiry signal to the access point again (S401). When the confirmation response signal is received (S403: YES), the process proceeds to S111 and the scan is executed. When the communication device 1 is a master device, the other communication devices are slave devices. Since the channel is scanned after waiting for a shorter time than the slave device, the transmission of the communication inquiry signal can be started earlier than the slave device. That is, priority is given to the communication apparatus 1 which is a master apparatus. Furthermore, it is possible to prevent the scan execution timing from being the same as that of other communication devices, and it is possible to prevent the communication device 1 and other communication devices from selecting the same channel at the same time.

  On the other hand, when the communication device 1 is a slave device, it waits for a longer time than the master device (S406). If the communication device 1 is a slave device, another communication device may be a master device. That is, priority is given to the start of communication by another communication device which is a master device. When the standby in the process of S406 ends, the CPU 21 transmits a communication inquiry signal to the access point again (S401), and receives the confirmation response signal (S403: YES), proceeds to the process of S111 and executes a scan. By executing the processing in this manner, priority is given to communication by the other communication device that is the master device, and it is possible to prevent the scan execution timing from being the same as that of the other communication device. For this reason, it can prevent that a some communication apparatus selects the same channel simultaneously.

  Note that the processes in FIGS. 7, 8, 14, and 15 are not necessarily realized by software, and may be realized by hardware.

  In the above embodiment, the use count DT51 corresponds to “data” of the present invention, and the use count data table storage area 241 corresponds to “storage device” of the present invention. The CPU 21 that performs the processing of S120 and S115 of FIG. 8 corresponds to the “storage control means” of the present invention, and the CPU 21 that performs the processing of S108 to S110 of FIGS. 7 and 8 is the “order determination means” of the present invention. Equivalent to. The CPU 21 that performs the processing of S111 to S119 in FIG. 8 corresponds to the “channel determination unit” of the present invention, and the predetermined number of times of use corresponds to the “second frequency” of the present invention. The CPU 21 that performs the process of S105 in FIG. 7 corresponds to the “frequency determination unit” of the present invention, and the CPU 21 that performs the process of S123 of FIG. 7 corresponds to the “display control unit” of the present invention. The display 11 corresponds to the “display screen” of the present invention, and the touch panel 12 corresponds to the “input means” of the present invention. The CPU 21 that performs the process of S305 in FIG. 14 corresponds to the “data storage control unit” of the present invention, and the CPU 21 that performs the process of S403 of FIG. 15 corresponds to the “scan determination unit” of the present invention.

  In the above embodiment, the processing of S120 and S115 of FIG. 8 corresponds to the “storage control step” of the present invention, and the processing of S108 to S110 of FIGS. 7 and 8 corresponds to the “order determination step” of the present invention. To do. S111 to S119 in FIG. 8 correspond to the “channel determination step” of the present invention.

1 Communication Device 11 Display 12 Touch Panel 21 CPU
32 communication control unit 33 timer 51 use count data table 241 use count data table storage area 244 recommunication start time storage area

Claims (12)

A communication device that performs a scan to detect whether or not a plurality of channels for performing wireless communication is used by a device that performs other communication, and determines the channel to perform communication,
The past time zone in which the scan was executed and the data in which a plurality of usage frequencies, which are frequencies at which the channels were used by devices that perform other communications in the past time zone, are associated with each channel. Storage control means for storing in a storage device;
In the data stored in the storage device by the storage control means, refer to the frequency of use of each channel in the past time zone that is the same as the current time zone, and determine the order of the channels for performing the scan Order determining means for determining;
A communication apparatus comprising: channel determining means for executing the scan in the order of the channels determined by the order determining means and determining the communicable channels. The order determining means includes
In the data stored in the storage device, refer to the usage frequency of each channel in the past time zone that is the same as the current time zone, and use frequency in the past time zone that is the same as the current time. The communication apparatus according to claim 1, wherein an order in which the scan is performed is determined in the order of the channels with a small number of channels. The order determining means includes
Referring to the frequency of use of each channel in the past time zone that is the same as the current time zone in the data stored in the storage device;
A first condition that is a condition that the use frequency of each of the adjacent channels is a channel having a frequency equal to or lower than a first frequency, both of which are predetermined use frequencies;
Among adjacent channels, a second condition that is a condition that one of the use frequency in the channel having a high frequency and the use frequency in a channel having a low frequency is a channel that is equal to or less than the first frequency;
A third condition that is a condition that the frequency of use is a channel that is equal to or lower than the first frequency continuously for a predetermined time; and
A fourth condition that is a condition that each channel is a predetermined frequency width or more away from the largest frequency and the smallest frequency in the communicable frequency band;
The scan is executed with reference to at least one condition of a fifth condition, which is a condition that the use frequency in the past time period that is the same as the current time period is a channel that is equal to or less than the first frequency. The communication apparatus according to claim 1, wherein an order of the channels is determined. The order determining means includes
The order in which the scan is executed in the order of the channel satisfying the first condition, the channel satisfying the second condition, the channel satisfying the third condition, the channel satisfying the fourth condition, and the channel satisfying the fifth condition. The communication device according to claim 3, wherein the communication device is determined. The channel determining means includes
When the scan is executed in the order of the channels determined by the order determination means, the received signal strength of the radio signal in the channel is measured, and the measured received signal strength is equal to or greater than a predetermined threshold In addition, the scan of the channels in the following order is performed, and when the measured received signal strength is smaller than the threshold, it is determined as a communicable channel. The communication device described. With reference to the frequency of use of the channel in the past time zone that is the same as the current time zone in the data stored in the storage device, the use in the past time zone that is the same as the current time zone A frequency determining means for determining whether or not the channel having a frequency equal to or lower than a second frequency that is a predetermined frequency exists;
When it is determined by the frequency determination means that the channel whose usage frequency in the same past time zone as the current time zone is less than or equal to the second frequency does not exist,
The order determining means does not determine the order;
The channel determining means does not determine the communicable channel,
When it is determined by the frequency determination means that the channel whose usage frequency in the same past time zone as the current time zone is less than or equal to the second frequency is present,
The order determining means determines the order;
The communication apparatus according to claim 1, wherein the channel determination unit determines the channel through which communication is possible.   There is a possibility that there is no usable channel when the frequency determining means determines that the channel whose usage frequency in the same past time zone as the current time zone is less than or equal to the second frequency does not exist. The communication apparatus according to claim 6, further comprising display control means for displaying that the value is high on the display screen. An input unit for inputting an instruction as to whether or not to execute the scan from a user;
In the case where it is determined by the frequency determining means that the channel whose usage frequency in the same past time zone as the current time zone is less than or equal to the second frequency does not exist,
When an instruction not to execute the scan is input by the user via the input unit,
The order determining means does not determine the order;
The channel determining means does not determine the communicable channel,
When an instruction to execute the scan is input by the user via the input means,
The order determining means determines the order;
The communication apparatus according to claim 6 or 7, wherein the channel determination means determines the communicable channel. When the communication device of the same type as the communication device and another communication device including the storage device that stores the data exists in the same environment,
9. The communication according to claim 1, further comprising data storage control means for receiving the data transmitted from the other communication device and storing the data in the storage device of the communication device. apparatus. When the communication device of the same type as the communication device and another communication device including the storage device that stores the data exists in the same environment,
Further comprising a scan determining means for determining whether or not the other communication device is executing the scan,
When it is determined by the scan determination means that the other communication device is executing the scan, the channel determination means does not execute the scan,
The channel determination unit executes the scan and determines the communicable channel when the scan determination unit determines that the other communication device is not executing the scan. The communication apparatus according to claim 1. A communication control method that is executed in a communication device that performs a scan to detect whether or not a plurality of channels for performing wireless communication is used by another device that performs communication and determines the channel to perform communication. And
The past time zone in which the scan was executed and the data in which a plurality of usage frequencies, which are frequencies at which the channels were used by devices that perform other communications in the past time zone, are associated with each channel. A storage control step to be stored in the storage device;
In the data stored in the storage device by the storage control means, refer to the frequency of use of each channel in the past time zone that is the same as the current time zone, and determine the order of the channels for performing the scan An order determination step to determine;
A communication control method, comprising: a channel determination step of executing the scan in the order of the channels determined by the order determination step and determining the channels that can communicate. A communication control program that is executed in a communication device that performs a scan to detect whether or not a plurality of channels for performing wireless communication are used by a device that performs other communication, and determines the channel to perform communication. And
In the CPU of the communication device,
Stores data in which a plurality of the past time zones in which the scan is executed and the usage frequency, which is the frequency at which each channel is used by a device that performs other communication in the past time zone, are associated with each channel. A storage control step to be stored in the device;
The order of the channels for performing the scan with reference to the frequency of use of the channels in the past time zone that is the same as the current time zone in the data stored in the storage device by the storage control means An order determination step to determine,
A communication control program that executes the scan in the order of the channels determined by the order determination step, and executes a channel determination step for determining the communicable channel.

Images