JP2018121210A - Wireless communication device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wireless communication device capable of reducing interruption frequency of operations caused by channel switching for applications requiring real time property.SOLUTION: A wireless communication device 1 designates a used channel from a plurality of channels included in a predetermined communication band and performs wireless communication. The wireless communication device 1 includes an application determination unit 32 for determining the presence or absence of real-time property of data communication corresponding to an application being executed, a communication quality determination unit 34 for determining whether the communication quality of the used channel has become worse than a predetermined threshold value, and a threshold value setting unit 36 for setting, at a first value (threshold value A), a threshold value when the real time property is not required for the data communication corresponding to the application being executed and setting a value when the real time property is required at a second value (threshold value B) lower than the first value.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a movable wireless communication device that is mounted on a vehicle or the like and performs wireless communication with another wireless device.

  Conventionally, there has been described a communication apparatus in which a threshold value of signal quality is variably set according to a communication load for each application (see, for example, Patent Document 1). For example, applications that perform streaming and data calls have a large communication load, applications such as net games that regularly perform communication are communication loads, applications such as mail and chat that mainly communicate text data have a small communication load, In principle, applications such as music players and memos that do not communicate are classified as having no communication load, and the signal quality threshold is increased as the communication load increases. As a result, it is possible to prevent the communication terminal that is executing an application with a high communication load from being offloaded even though the communication quality that the communication apparatus can provide is low.

JP, 2014-212417, A

  By the way, in the communication apparatus disclosed in Patent Document 1 described above, it is attempted to obtain necessary signal quality in consideration of the communication load for each application, and in use when the signal quality falls below a set threshold value. The channel will be switched. For example, when an application communicates using streaming, real-time performance is required. However, in the communication device of Patent Document 1, a signal quality threshold is set high for an application with a large communication load that executes streaming. Therefore, when the signal quality (communication state) deteriorates, the use channel is switched, and there is a problem that the application operation is interrupted due to the switching. Since the interruption of the application operation causes a sound cut or a stop of the moving image, it is desired to reduce it as much as possible.

  The present invention has been created in view of the above points, and an object of the present invention is to provide a wireless communication apparatus that can reduce the frequency of interruption of operations caused by channel switching for applications that require real-time performance. There is.

  In order to solve the above-described problem, a wireless communication device according to the present invention is an application that is being executed in a wireless communication device that performs wireless communication by designating a use channel from among a plurality of channels included in a predetermined communication band. Application determination means for determining the presence or absence of corresponding data communication in real time, communication quality determination means for determining whether or not the communication quality of the used channel has deteriorated below a predetermined threshold, and data corresponding to the application being executed Threshold setting means for setting the threshold to a first value when real-time capability is not required for communication and setting the threshold to a second value lower than the first value when real-time capability is required.

  For applications that require real-time performance, the communication quality threshold that is the basis for switching the channel used is set low, so the number of channel switching can be reduced, and the frequency of application operation interruptions caused by channel switching is reduced. It becomes possible to do.

  In addition, it is desirable that the second value described above is set higher than the minimum value of communication quality that does not interrupt the operation of a running application that requires real-time performance. As a result, it is possible to reliably ensure a state in which the application operation is not interrupted.

  In addition, the above-described application that requires real-time property is preferably an application that performs data communication by streaming. As a result, it is possible to prevent the output of audio or music obtained by using streaming distribution or the display of moving images from being temporarily stopped.

  In addition, a real-time information storage unit that stores information indicating the presence or absence of real-time property of data communication for each application is further provided, and the application determination unit determines the presence or absence of real-time property based on the information stored in the real-time information storage unit It is desirable. Thereby, the presence or absence of the real-time property of data communication can be appropriately determined for each application, and erroneous determination can be prevented.

  In addition to the above-mentioned used channels, channel search means for searching for other channels whose communication quality is higher than the second value in parallel with the communication operation using the used channels, and applications that require real-time processing are being executed. In addition, it is desirable to further include channel switching means for switching the used channel to another channel when the communication quality of the used channel becomes lower than the second value. Accordingly, when the communication state of the used channel deteriorates during the communication operation using the used channel, it is possible to quickly switch to another channel having a good communication state.

It is a figure which shows the structure of the radio | wireless communication apparatus of one Embodiment. It is a flowchart which shows the operation | movement procedure which changes communication quality during communication by executing an application and switches a use channel. It is a figure which shows the outline | summary of the channel switching according to the presence or absence of the real-time property of communication.

  Hereinafter, a wireless communication apparatus according to an embodiment to which the present invention is applied will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating a configuration of a wireless communication apparatus according to an embodiment. A wireless communication apparatus 1 shown in FIG. 1 is for performing wireless communication by designating a use channel from among a plurality of channels included in the 2.4 GHz band and the 5 GHz band, and includes wireless communication units 10 and 20, DFS. (Dynamic Frequency Selection) function units 12 and 22, a channel switching processing unit (Ch switching processing unit) 30, a scanning processing unit (SCAN processing unit) 40, and a memory 50 are configured. The wireless communication device 1 is mounted on a vehicle. The wireless communication device 1 is built in or externally attached to a head unit as an in-vehicle device that performs a navigation operation, a radio reception operation, an audio reproduction operation, a moving image reproduction operation, and the like, and is a terminal device (not shown) such as a smartphone. ) Operates as an access point when performing wireless communication with the device. This in-vehicle device includes an application processing unit 2 shown in FIG.

  The application processing unit 2 executes a plurality of applications (AP1, AP2, AP3, AP4) to realize a predetermined operation corresponding to each application. For example, by executing the application AP1, the audio data transmitted from the terminal device by wireless communication in the streaming format is acquired and reproduced (audio output). Further, by executing the application AP2, moving image data transmitted from the terminal device in a streaming format by wireless communication is acquired and reproduced (moving image display). Also, by executing the application AP3, data for Android Auto (registered trademark) transmitted from the terminal device by wireless communication is acquired, and the display screen (operation of the terminal device indicated by this data) Screen) and the like, and the operation content of the user using the display screen is transmitted to the terminal device. By executing the application AP4, reproduction data (music data and moving image data) stored in the terminal device is acquired and stored by wireless communication in the best-effort format, and is designated from among them in accordance with a user instruction. Play music / video with the title.

  Among these, the application AP1 is required to have a real-time property (there is a real-time property) because the sound interruption occurs when the wireless communication with the terminal device is interrupted. Similarly, when wireless communication with the terminal device is interrupted, the application AP2 is required to have a real-time property (there is real-time property) because the motion of the moving image stops. Further, the application AP3 is required to have real-time properties because there is a delay in updating the contents of the display screen or a delay in user operation instructions when wireless communication with the terminal device is interrupted (with real-time properties). On the other hand, the application AP4 does not require real-time performance (no real-time performance) because the music / video playback is not interrupted even when wireless communication with the terminal device is interrupted. Note that these applications AP1 to AP4 are examples for explaining the presence / absence of real-time property, and are not limited to these.

  The wireless communication unit 10 controls wireless communication by Wi-Fi using any channel included in the 2.4 GHz band and the 5 GHz band based on standards such as IEEE 802.11. Similarly, the wireless communication unit 20 controls wireless communication by Wi-Fi using any channel included in the 2.4 GHz band and the 5 GHz band based on a standard such as IEEE 802.11. The 5 GHz band described above includes channels belonging to the W53 and W56 types, which are bands in which interference with weather radar and the like occurs.

  The DFS function unit 12 detects a radio wave used by a weather radar or the like (radar detection) for a channel used for wireless communication in the wireless communication unit 10 and performs processing for performing communication while avoiding the channel. Similarly, the DFS function unit 22 detects a radio wave used by a weather radar or the like (radar detection) for a channel used for wireless communication in the wireless communication unit 20, and performs processing to avoid the channel and perform communication. I do.

  The channel switching processing unit 30 switches the channel used in each of the wireless communication units 10 and 20.

  The scan processing unit 40 switches channels used by the wireless communication unit 20 in a predetermined order to search for channels with good communication quality (good radio wave condition / high throughput). This channel search is performed in the background in parallel with the communication operation using the wireless communication unit 10.

  The memory 50 has a real-time (RT) information storage unit 52. The real-time information storage unit 52 stores information indicating the presence or absence of real-time communication for each application executed by the application processing unit 2. For example, information indicating the presence or absence of real-time property is stored in the real-time information storage unit 52 for each of the four applications AP1 to AP4 included in the application processing unit 2 illustrated in FIG.

  The channel switching processing unit 30 described above includes an application determining unit (AP determining unit) 32, a communication quality determining unit 34, a threshold setting unit 36, and a channel switching unit (Ch switching unit) 38.

  The application determination unit 32 determines whether or not there is real-time communication for each of the applications that are being executed with data communication. This determination is made based on information stored in the real-time information storage unit 52 in the memory 50, for example.

  The communication quality determination unit 34 determines whether or not the communication quality of a channel (used channel) used for communication by the wireless communication unit 10 has deteriorated below a predetermined threshold. The threshold value setting unit 36 sets the threshold value to the first value (threshold value A) when real-time property is not necessary for the application being executed, and sets the threshold value to a second value lower than the first value when real-time property is necessary. (Threshold B <threshold A).

  The channel switching unit 38 uses the wireless communication unit 10 when the communication quality of the channel used by the wireless communication unit 10 is lower than the second value (threshold value B) while executing an application that requires real-time performance. The channel is switched to another channel whose communication quality is higher than the second threshold. Further, the channel switching unit 38 is configured to execute the wireless communication unit 10 when the communication quality of the channel used by the wireless communication unit 10 becomes lower than the first value (threshold A) while executing an application that does not require real-time performance. Is switched to another channel whose communication quality is higher than the first threshold.

  The application determination unit 32 described above is the application determination unit, the communication quality determination unit 34 is the communication quality determination unit, the threshold setting unit 36 is the threshold setting unit, the real-time information storage unit 52 is the real-time storage unit, and the scan processing unit 40 is The channel switching unit 38 corresponds to the channel switching unit.

  The wireless communication apparatus 1 of the present embodiment has such a configuration, and the operation thereof will be described next.

  FIG. 2 is a flowchart showing an operation procedure for switching the use channel due to the communication quality changing during communication by executing the application. This operation procedure is performed at predetermined time intervals for each application when there are a plurality of applications being executed.

  For example, when the application AP1 shown in FIG. 1 is executed and communication using the channel used by the wireless communication unit 10 is started, the application determination unit 32 determines whether or not the application AP1 being executed has real-time characteristics. Is determined (step 100). If there is real-time capability, an affirmative determination is made, and then the communication quality determination unit 34 determines whether or not the communication quality of the channel used by the wireless communication unit 10 is equal to or less than the threshold value B (step 102). This threshold B is set higher than the minimum value of communication quality that does not interrupt the operation (audio reproduction) of the application AP1 being executed. For example, the amount of communication corresponding to an application can be measured by measuring a delay using a ping command, or measuring the amount of data in a transmission / reception buffer provided in the wireless communication unit 10 or the amount of data transmitted / received at a certain time. It is desirable to detect the threshold value and set the threshold value B based on the detection result. If the communication quality is higher than the threshold value B, a negative determination is made in the determination of step 102, and the series of processes related to the switching of the used channel is terminated without switching the used channel.

  Further, when the communication quality is equal to or lower than the threshold value B, that is, when the communication quality of the used channel is lowered so that the operation of the application AP1 is interrupted, an affirmative determination is made in the determination of step 102. Next, the channel switching unit 38 determines whether there is another channel whose communication quality is higher than the threshold B (step 104). The search for other channels is performed in the background in parallel with the communication operation using the wireless communication unit 10 by the scan processing unit 40 using the wireless communication unit 20, and the determination in step 104 is the result of this search. This can be done quickly by referring to. If there is no other applicable channel, a negative determination is made in the determination in step 104, and the series of processing relating to the switching of the used channel is terminated without switching the used channel.

  If there is another channel whose communication quality is higher than the threshold value B, an affirmative determination is made in the determination of step 104. Next, the channel switching unit 38 switches the channel used by the wireless communication unit 10 to another channel whose communication quality is higher than the threshold value B (step 106). Since this channel switching is performed using another channel that has already been specified by the search at that time, the time required for the switching is minimal, and the interruption time of the application operation caused by the channel switching is shortened. can do. Further, the channel switching can be performed also in the terminal device by notifying the terminal device of channel switching by CSA (channel-switch-announcement) from the wireless communication device 1 as an access point. After the used channel is switched in this way, a series of processes relating to the used channel switching due to the communication quality deterioration is completed.

  As described above, in the case of the application AP1, the application AP2, and the AP3, since there is real-time property, an affirmative determination is made in the determination of Step 100, and the operation procedure after Step 102 described above is performed.

  On the other hand, when the application AP4 is being executed, the communication in which the application AP4 is being executed does not have real-time characteristics, and therefore a negative determination is made in the determination of step 100. In this case, next, the communication quality determination unit 34 determines whether or not the communication quality of the channel used by the wireless communication unit 10 is equal to or less than the threshold value A (step 108). This threshold A is set higher than the above-described threshold B regardless of the minimum value of the communication quality that does not interrupt the operation of the application AP4 being executed (reproduction of title music / moving image). If the communication quality is higher than the threshold value A, a negative determination is made in the determination in step 108, and the series of processing relating to the use channel switching due to the communication quality deterioration is terminated without switching the use channel.

  Further, when the communication quality is equal to or lower than the threshold value A, an affirmative determination is made in the determination of step 108. Next, the channel switching unit 38 determines whether there is another channel whose communication quality is higher than the threshold A (step 110). The search of other channels is performed in the background in parallel with the communication operation using the wireless communication unit 10 by the scan processing unit 40 using the wireless communication unit 20, and the determination in step 110 is the result of this search. This can be done quickly by referring to. If there is no other applicable channel, a negative determination is made in the determination in step 110, and the series of processing relating to the switching of the used channel is terminated without switching the used channel.

  If there is another channel whose communication quality is higher than the threshold A, an affirmative determination is made in the determination in step 110. Next, the channel switching unit 38 switches the channel used by the wireless communication unit 10 to another channel whose communication quality is higher than the threshold A (step 112). After the used channel is switched in this way, a series of processes relating to the used channel switching due to the communication quality deterioration is completed.

  FIG. 3 is a diagram showing an overview of channel switching according to the presence or absence of real-time communication. FIG. 3A shows an overview of channel switching during execution of an application that does not require real-time property for communication (no real-time property). In this case, the communication quality threshold A for determining channel switching is set to a high value. Therefore, a situation in which the communication quality of the used channel (ch1) at that time fluctuates and falls below the threshold value A tends to occur. When the communication quality becomes equal to or lower than the threshold A, the channel is quickly switched to another channel (ch2) whose communication quality is higher than the threshold A. For the same reason, the communication quality of this channel (ch2) is likely to fluctuate and fall below the threshold A. When the communication quality becomes equal to or lower than the threshold A, the channel is switched to another channel (ch3) whose communication quality is higher than the threshold A again.

  On the other hand, FIG. 3B shows an overview of channel switching during execution of an application that requires real-time communication (with real-time property). In this case, the communication quality threshold B for determining channel switching is set to a low value. Therefore, a situation in which the communication quality of the used channel (ch1) at that time fluctuates and falls below the threshold value B hardly occurs. For this reason, the channel used by the wireless communication unit 10 cannot be switched to another channel, or the number of times of switching is reduced.

  As described above, in the wireless communication device 1 of the present embodiment, for applications that require real-time performance, the communication quality threshold B serving as a reference for switching the used channel is set low, so the number of channel switching is reduced. Therefore, it is possible to reduce the frequency of interruption of application operations caused by channel switching.

  In addition, since this threshold value B is set higher than the minimum value of the communication quality that does not interrupt the operation of the running application that requires real-time performance, it is possible to reliably ensure that the application operation is not interrupted. Become.

  In addition, by making the application that requires real-time performance an application that performs communication by streaming, it is possible to prevent temporarily stopping the output of audio and music output and video obtained by using streaming delivery. Can do.

  In addition, by providing a real-time information storage unit 52 that stores information indicating the presence / absence of real-time data communication for each application, it is possible to appropriately determine the presence / absence of communication real-time for each application. Can be prevented.

  In addition, during the communication operation using the used channel, the search for other channels to be switched to when the communication quality of the used channel is reduced is performed in the background in parallel with the communication operation using the used channel. When the communication state of this use channel deteriorates, it becomes possible to quickly switch to another channel having a good communication state.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation implementation is possible within the range of the summary of this invention. For example, in the above-described embodiment, the two wireless communication units 10 and 20 are provided, and the other wireless communication unit 20 is used to search for another channel in parallel with the communication operation by one wireless communication unit 10. Although the case of performing in the background has been described, the present invention can also be applied to the case where only the wireless communication unit 10 is provided. In this case, when the communication quality of the used channel falls below the threshold value A or the threshold value B, the search for another channel is started. Even in this case, the application operation has real-time characteristics. Since the switching frequency of the used channel in the accompanying communication can be reduced, it is possible to reduce the interruption frequency of the application operation caused by the channel switching.

  Moreover, although embodiment mentioned above demonstrated the radio | wireless communication apparatus mounted in the vehicle, this invention is also applicable to the radio | wireless communication apparatus incorporated in portable terminal devices, such as a smart phone.

  In the above-described embodiment, the case where communication is performed using channels included in the 2.4 GHz band and the 5 GHz band has been described. However, the band to be used is not limited to these, and either one of these or The present invention can be applied to a case where communication is performed using a channel included in another communication band.

  In the above-described embodiment, the case where the wireless communication device 1 operates as an access point has been described. However, the present invention also applies to a case where the wireless communication device 1 communicates with another access point as a station (STA). Can be applied.

  As described above, according to the present invention, for applications that require real-time performance, the communication quality threshold value that serves as a reference for switching the used channel is set low, so the number of channel switching can be reduced. It is possible to reduce the frequency of interruption of application operations caused by channel switching.

DESCRIPTION OF SYMBOLS 1 Wireless communication apparatus 10, 20 Wireless communication part 12, 22 DFS function part 30 Channel switching process part (Ch switching process part)
32 Application determination unit (AP determination unit)
34 Communication quality determination unit 36 Threshold setting unit 38 Channel switching unit (Ch switching unit)
40 Scan processing unit (SCAN processing unit)
50 memory 52 real-time (RT) information storage

Claims (5)

In a wireless communication apparatus that performs wireless communication by designating a use channel from a plurality of channels included in a predetermined communication band,
Application determination means for determining the presence or absence of real-time data communication corresponding to the application being executed;
Communication quality determining means for determining whether or not the communication quality of the used channel has deteriorated below a predetermined threshold;
When the real-time property is not required for data communication corresponding to the application being executed, the threshold value is set to the first value, and when the real-time property is required, the threshold value is set to a second value lower than the first value. Threshold setting means for setting;
A wireless communication apparatus comprising:   The wireless communication apparatus according to claim 1, wherein the second value is set to be higher than a minimum value of communication quality that does not interrupt an operation of a running application that requires the real-time property.   The wireless communication apparatus according to claim 1, wherein the application that requires real-time property is an application that performs data communication by streaming. Further comprising real-time information storage means for storing information indicating the presence or absence of real-time data communication for each application;
The wireless communication apparatus according to any one of claims 1 to 3, wherein the application determination unit determines whether or not there is real-time property based on information stored in the real-time information storage unit. Channel search means for searching other channels whose communication quality is higher than the second value other than the used channels in parallel with the communication operation using the used channels;
Channel switching means for switching the used channel to the other channel when the communication quality of the used channel becomes lower than the second value during execution of the application requiring the real-time property;
The wireless communication apparatus according to claim 1, further comprising:

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