JP7616026B2 - COMMUNICATION DEVICE, COMMUNICATION METHOD, AND COMMUNICATION PROGRAM - Google Patents

Description

The present invention relates to a communication device, a communication method, and a communication program that perform bandwidth estimation.

When transmitting and receiving data using a communication device, the amount of data transmitted is controlled to match the bandwidth of the communication line in order to prevent data loss during communication and the resulting need for retransmission.

Patent document 1 discloses a communication terminal device that can estimate the available bandwidth taking into account the impact of multiple applications using the network simultaneously.

JP 2010-62720 A

Here, the present inventors have found the following problem.
In the case where the communication speed of a communication device is limited by an external factor, i.e., an event that is not dependent on the communication environment of the communication line, performing bandwidth estimation even though the upper limit of the communication speed is known results in waste of hardware and communication line resources. That is, performing a calculation for bandwidth estimation consumes resources of the calculation unit and increases power consumption. In addition, transmitting the bandwidth estimation result consumes resources of the communication line.

The present invention aims to realize a communication device etc. that can effectively utilize the resources of hardware and communication lines when communication speed is limited by an event that is not dependent on the communication environment of the communication line.

The communication device (100) of the present disclosure is a communication device that communicates with another communication device via a communication line,
A receiving unit (101) for receiving data from the other communication device;
A communication speed limit determination unit (102) that determines the occurrence of a speed limit that is not dependent on the communication environment of the communication line;
a bandwidth estimation timing determination unit (103) that determines a timing for bandwidth estimation when the communication speed limit determination unit determines that the speed limit has occurred;
A bandwidth estimation unit (104) that estimates a bandwidth of the communication line at the timing and generates a bandwidth estimation result;
A transmission unit (105) that transmits the bandwidth estimation result to the other communication device;
has.

The numbers in parentheses attached to the constituent elements of the invention described in the claims and this section indicate the correspondence between the present invention and the embodiments described below, and are not intended to limit the present invention.

With the above-mentioned configuration, the communication device etc. disclosed herein can effectively utilize the resources of the hardware and communication lines when the communication speed is limited due to an event that is not dependent on the communication environment of the communication line.

FIG. 1 is an explanatory diagram showing the configuration and operation of each embodiment; FIG. 1 is a diagram showing the configuration of a communication device according to first to fourth embodiments. FIG. 1 is an explanatory diagram for explaining data used by a communication speed detection unit of a communication device according to a first embodiment. FIG. 1 is an explanatory diagram for explaining data used by a communication speed detection unit of a communication device according to a first embodiment. FIG. 1 is an explanatory diagram for explaining information stored in a storage unit of a communication device according to the first to fourth embodiments. FIG. 1 is a flow diagram showing the operation of the communication device according to the first to fourth embodiments. FIG. 1 is an explanatory diagram illustrating an example of an operation of a communication device according to a first embodiment; FIG. 1 is a diagram showing the configuration of a communication device according to a fifth to sixth embodiment; FIG. 23 is an explanatory diagram showing the operation of a communication device according to a first embodiment of the sixth embodiment; FIG. 23 is an explanatory diagram showing the operation of a communication device according to a first embodiment of the sixth embodiment; FIG. 2 is an explanatory diagram showing the operation of a communication device according to a second embodiment of the sixth embodiment; FIG. 23 is an explanatory diagram for explaining the operation of a communication device according to a third embodiment of the sixth embodiment. FIG. 2 is an explanatory diagram for explaining the operation of a communication device according to a fourth embodiment of the sixth embodiment.

The following describes an embodiment of the present invention with reference to the drawings.

The present invention refers to the invention described in the claims or in the Means for Solving the Problems section, and is not limited to the following embodiments. Furthermore, at least the words in quotation marks refer to the words described in the claims or in the Means for Solving the Problems section, and are not limited to the following embodiments.

The configurations and methods described in the dependent claims of the claims are optional configurations and methods in the invention described in the independent claims of the claims. The configurations and methods of the embodiments corresponding to the configurations and methods described in the dependent claims, and the configurations and methods described only in the embodiments without being described in the claims, are optional configurations and methods in the present invention. The configurations and methods described in the embodiments when the description of the claims is broader than the description of the embodiments are also optional configurations and methods in the present invention in the sense that they are examples of the configurations and methods of the present invention. In either case, by being described in the independent claims of the claims, they become essential configurations and methods of the present invention.

The effects described in the embodiments are the effects when the configuration of the embodiment is an example of the present invention, and are not necessarily the effects of the present invention.

When there are multiple embodiments, the configurations disclosed in each embodiment are not limited to each embodiment, but can be combined across the embodiments. For example, a configuration disclosed in one embodiment may be combined with another embodiment. Also, the configurations disclosed in each of the multiple embodiments may be collected and combined.

The problem described in the problem that the invention is intended to solve is not a publicly known problem, but was discovered independently by the inventor, and this fact, together with the configuration and method of the present invention, affirms the inventive step of the invention.

1. Configuration and Operation Prerequisite for Each Embodiment The configuration and operation prerequisite for each embodiment will be outlined below with reference to FIG.
The communication device 100 communicates with another communication device 150 via a communication line.
Specifically, the communication device 100 receives data transmitted from another communication device 150 via a reception line. Next, the communication device 100 estimates the bandwidth of the communication line to generate a bandwidth estimation result. Then, the communication device 100 transmits the generated bandwidth estimation result to the other communication device 150 via a transmission line. The other communication device 150 receives the bandwidth estimation result. Then, the other communication device 150 uses the bandwidth estimation result to control communication with the communication device 100. Here, the communication line for receiving data is expressed as a reception line and the communication line for transmitting data is expressed as a transmission line, but the same physical communication line may be used.

The communication line to be estimated is primarily a receiving line, but may also be a transmitting line. In addition, the communication line to be estimated may be only a receiving line, only a transmitting line, or both a receiving line and a transmitting line.

The communication line is primarily a wireless communication line, but may also be a wired communication line.
Examples of wireless communication lines include communication lines based on a mobile communication system, such as W-CDMA (Wideband Code Division Multiple Access), HSPA (High Speed Packet Access), LTE (Long Term Evolution), LTE-A (Long Term Evolution Advanced), 4G, 5G, 6G, or LPWA (Low Power Wide Area). In addition, communication lines based on wireless communication methods such as IEEE802.11 (Wi-Fi (registered trademark)), IEEE802.16 (WiMAX (registered trademark)), Bluetooth (registered trademark), UWB (Ultra Wide Band), ZigBee (registered trademark), or DSRC (Dedicated Short Range Communication) can also be used.

Examples of wired communication lines include LANs (Local Area Networks) such as Ethernet (registered trademark), optical fiber lines, or fixed telephone lines.

In addition, the communication line may be a combination of a wireless communication line and a wired communication line. For example, if the communication device 100 is a terminal device and the other communication device 150 is a server device connected to the Internet, the communication line between the communication device 100 and the base station device is a 4G wireless communication system, and between the base station device and the server device is a wired communication system consisting of an optical line.

The communication device 100 may be either a terminal device or a server device. Furthermore, the other communication device 150 may also be either a terminal device or a server device. In other words, as long as the prerequisite conditions are met, each embodiment can be applied to communication between terminal devices, communication between a terminal device and a server device, and communication between servers. Furthermore, the communication device 100 or the other communication device 150 may be a device that is interposed between a terminal device and a server device, such as a base station device or a gateway device.

The communication device 100 or another communication device 150 may be "mounted" on a "mobile object" such as a vehicle.
Where:
"Mobile object" refers to an object that can move and can move at any speed. It also includes cases where the mobile object is stationary. For example, it includes, but is not limited to, automobiles, motorcycles, bicycles, pedestrians, ships, aircraft, and objects mounted on these.
"Mounted" includes not only the case where the device is directly fixed to the moving body, but also the case where the device is not fixed to the moving body but moves with the moving body, such as the case where the device is carried by a person riding on the moving body, or the case where the device is mounted on cargo placed on the moving body.

The communication device 100 and the other communication device 150 can have the same configuration if they are devices of the same type.
In the following embodiments, the configuration and operation of the communication device 100 will be described.

2. Embodiment 1
(1) Configuration of the communication device 100 of this embodiment The configuration of the communication device 100 of the first embodiment will be described with reference to Fig. 2. The communication device 100 has a receiving unit 101, a communication speed limit determination unit 102, a bandwidth estimation timing determination unit 103, a bandwidth estimation unit 104, a transmitting unit 105, a bandwidth estimation data generation unit 106, and a storage unit 107. The communication speed limit determination unit 102 has at least one of a communication speed detection unit 108, a communication volume detection unit 109 , a temperature detection unit 110, and a voltage detection unit 111. In this embodiment, a case in which the communication speed detection unit 108 is included will be described.

The communication device 100 can be configured with a general-purpose CPU (Central Processing Unit), a volatile memory such as a RAM, a non-volatile memory such as a ROM, a flash memory, or a hard disk, various interfaces, and an internal bus connecting these. The communication device 100 can be configured to perform the functions of each functional block shown in FIG. 2 by executing software on this hardware.
Of course, the communication device 100 may be realized by dedicated hardware such as an LSI.
The above also applies to the communication devices of the other embodiments.

In this embodiment, the communication device 100 is assumed to be in the form of an electronic control device (ECU (Electric Control Unit), hereinafter abbreviated as ECU) as a semi-finished product, but is not limited to this. For example, the form of a component may be a semiconductor circuit or a semiconductor module, the form of a semi-finished product may be an electronic control device, an electronic control unit, or a system board, and the form of a finished product may be a server, a workstation, a personal computer (PC), a tablet, a smartphone, a mobile phone, or a navigation system.
The communication device 100 may be configured with a single ECU or multiple ECUs.
The above also applies to the communication devices of the other embodiments.

The receiving unit 101 receives "data" from another communication device 150 via a communication line.
Here, "data" includes data stored in the payload, as well as data that is determined to be exchanged using a communication protocol such as an acknowledgement (ACK) packet used for transmission control in TCP (Transmission Control Protocol), or bandwidth estimation data that is generated and transmitted by another communication device for the purpose of bandwidth estimation.

The communication speed limit determination unit 102 determines the occurrence of a "speed limit" that is not dependent on an external factor, i.e., the communication environment of the communication line. An example of a speed limit that is not dependent on the communication environment of the communication line is when, for example, a wireless communication method is used, and when a predetermined communication volume per month is exceeded, the communication speed is limited to a certain value (e.g., 128 kbps). Alternatively, when the temperature of the communication device 100 becomes high, the communication device 100 goes into a degenerate mode for cooling, and the communication speed is limited. Alternatively, when using a battery, for example, when the input voltage input to the communication device 100 drops and normal operation cannot be maintained, the communication device 100 goes into a degenerate mode to maintain a minimum communication function, and the communication limit is limited. The degenerate mode is a mode that does not stop the communication function itself, but aims to resolve an abnormal situation by temporarily limiting performance. In either case, the speed limit occurs regardless of the communication environment of the communication line.
Here, "speed restriction" includes cases where the speed is restricted directly, as well as cases where the speed is restricted as a result of restricting the frequency band, bandwidth, etc.

In contrast, speed restrictions that depend on the communication environment of the communication line include, for example, cases where the communication speed is reduced or restricted when traffic on the communication line is congested. Such cases do not fall under the speed restrictions of this embodiment.

In other words, the speed limit in this embodiment is based on an event that is expected to continue for a certain period of time.

In this embodiment, the communication speed limit determination unit 102 includes a communication speed detection unit 108. The communication speed detection unit 108 detects the communication speed of the communication line "based on the data" received by the receiving unit 101.
Here, "based on data" includes cases based on the contents of the data as well as cases based on attributes of the data, such as data size, data transmission time, data reception time, and data reception strength.

An example of detection of the communication speed by the communication speed detection unit 108 of this embodiment will be described.
First, another communication device 150 transmits data including a transmission time t1 [s] to the communication device 100. The data is received by the receiving unit 101 of the communication device 100, and the communication device 100 records the reception time t2 [s]. Then, the communication speed detection unit 108 extracts the data size D [bit] and t1 [s] of the received data from the data, and calculates the communication speed S [bps] on the receiving line using the following formula.

S=D/(t2-t1)

It is assumed that the communication device 100 and the other communication device 150 are time-synchronized using a known method such as GPS.
Of course, the communication speed may be detected using a method other than the above.

Next, the data used by the communication speed detection unit 108 to detect the communication speed will be described with reference to FIGS.
Although data with a small data size has a small transmission data load, as shown in Fig. 3, the transmission load of data with a small data load is insufficient for the available communication band, making the communication speed appear to be low. Also, as shown in Fig. 4, data with a small data size is sent and received in an extremely short time, resulting in low accuracy.
Therefore, it is preferable that the communication speed detection unit 108 of the present embodiment detects the communication speed based on data that is "larger than" a "predetermined data size" among the received data.
Where:
The "predetermined data size" may be a fixed value or may be a variable value that varies depending on conditions.
The term "larger" encompasses both the case where the data size is included in comparison with a predetermined data size and the case where the data size is not included in the predetermined data size.

As shown in Figures 3 and 4, for example, an area where a statistically constant upper limit of communication speed exists is detected, and the lower limit of that area can be set as the predetermined data size. For example, in the case of Figure 3, the data size corresponding to the transmission data load p can be set as the predetermined data size, and in the case of Figure 4, the data size q can be set as the predetermined data size.

The storage unit 107 stores the cause of an event accompanied by a speed limit, and a reference communication speed which is a communication speed determined when an event accompanied by a speed limit occurs.
A specific example of information stored in the storage unit 107 will be described with reference to FIG.

Consider line 1 in FIG.
When using a wireless communication system, if a certain communication volume is exceeded in a certain period of time, the communication speed may be limited to a certain value. In the case of Fig. 5, if the communication volume per month exceeds 6 GB, the communication speed is limited to 128 kbps, which corresponds to the reference communication speed when event A, that is, the communication volume is exceeded, occurs.
In addition, when the temperature of the communication device 100 becomes higher than a predetermined temperature, the device goes into degenerate mode for cooling, and the communication speed is limited to a certain value. In the case of Fig. 5, when the temperature of the communication module exceeds 60°C, the communication speed is limited to 30 kbps, which corresponds to the reference communication speed when the event B occurs in which the temperature of the communication device 100 becomes higher than the predetermined temperature.
Furthermore, if the input voltage of the communication device 100 falls below a predetermined input voltage, the device goes into degenerate mode in order to maintain a minimum communication function, and the communication speed is limited to a certain value. In the case of Fig. 5, when the input voltage of the communication module falls below the threshold, the communication speed is limited to 50 kbps, which corresponds to the reference communication speed when event C occurs, in which the input voltage of the communication device 100 falls below the predetermined input voltage.

5, a certain width is set for the reference communication speed, but this is to take error into consideration. Also, when the reference communication speed is low, the error becomes large, so it is desirable to set a large width.
As shown in FIG. 5, the reference communication speed may be determined by a median value and an error range, or may be determined by an upper limit value and a lower limit value, or a median value and a variance value.

The storage unit 107 further stores a reference timing corresponding to a reference communication speed.
5, the reference timing is defined by the number of decimations, which is the number of times that the band estimation is decimated with respect to the normal band estimation timing. For example, when the normal band estimation timing periodically performs band estimation at a predetermined time interval, such as [1, 2, 3, 4, 5, 6, 7, 8, 9], applying the number of decimations + 3 results in [1, 5, 9], the band estimation interval becomes four times, and the band estimation frequency becomes 1/4.

The first time at the bandwidth estimation timing refers to the number of times that it is determined that a communication speed limit has occurred, when it is the first time. Similarly, the second time or later refers to the number of times that it is determined that a communication speed limit has occurred, when it is the second time or later. For example, when event A occurs, +3 is applied the first time, and +2 is also applied the second time, so that a number of times of thinning of +5 is applied to the normal bandwidth estimation timing. In other words, the longer the duration of the speed limit, the more the number of times of thinning is added.
In contrast, for event B, the number of thinning-out times is not incremented since it is 0 from the second time onwards, and the number of thinning-out times remains constant while event B is continuing. The same is true for event C.

In this embodiment, the reference timing is defined by the number of times of thinning out, but it may be defined by other methods. For example, it may be defined by a thinning out ratio, which is a ratio of thinning out, or a thinning out time, which is a time for thinning out. Alternatively, the band estimation frequency or the band estimation interval may be directly defined. Furthermore, multiple divisions defined by the number of times of thinning out or the elapsed time may be set.
In addition, since the thinning ratio is the number of times thinning is performed relative to a reference number of times, it can also be evaluated as the "number of times thinning is performed."

Furthermore, when multiple communication lines are used, the reference communication speed and reference timing may be specified for each communication line, as shown in Figure 5.

In this embodiment, the communication speed limit determination unit 102 determines that a speed limit has occurred when the communication speed detected by the communication speed detection unit 108 is "constant" and "matches" the reference communication speed.
Where:
"Constant" does not necessarily mean that the absolute value is always constant, but rather that it is sufficient that the value is constant when observed statistically, taking into account errors and the like.
The term "match" does not necessarily mean a perfect match, but rather a match that can be statistically observed while taking into account errors and the like.

Specifically, in this embodiment, the communication speed detection unit 108 detects the communication speed for a specified period of time, and determines that the communication speed has become constant if the variance of the communication speed during the specified period is within a certain value or if the difference from the average value is within a certain percentage.
Then, the reference communication speed is read from the storage unit 107, and it is determined whether the communication speed detected by the communication speed detection unit 108 matches the reference communication speed.

When communication speed limit determination section 102 determines that a speed limit has occurred, bandwidth estimation timing determination section 103 determines the "timing" of bandwidth estimation.
Specifically, in this embodiment, the bandwidth estimation timing determination unit 103 reads out the reference timing corresponding to the communication speed detected by the communication speed detection unit 108 from the storage unit 107, and determines it as the timing for bandwidth estimation. For example, in the case of Fig. 5, when the communication speed detected by the communication speed detection unit 108 is 135 [kbps], which is within 128 [kbps] ±10% of event A, the communication speed limit determination unit 102 determines that the speed limit of event A has occurred. Then, the bandwidth estimation timing determination unit 103 reads out +3, which is the reference timing of event A, and determines this as the timing for bandwidth estimation.
Here, "timing" may refer to any time element that can identify the bandwidth estimation, such as a bandwidth estimation interval, which is the time interval at which the bandwidth estimation is performed, a bandwidth estimation frequency, which is the number of times the bandwidth estimation is performed per unit time, and a bandwidth estimation time, which is an absolute time or a relative time at which the bandwidth estimation is performed. An example of a relative time is a timer.

The reference timing stored in the storage unit 107 specifies that the bandwidth estimation should be thinned out with respect to the normal bandwidth estimation timing, so the timing determined by the bandwidth estimation timing determination unit 103 has a reduced number of bandwidth estimates per unit time compared to when no speed limit is occurring.

The bandwidth estimation unit 104 estimates the bandwidth of the communication line at the timing determined by the bandwidth estimation timing determination unit 103 to generate a bandwidth estimation result. The bandwidth of the communication line can be estimated by a known method, but in this embodiment, an estimate of the communication speed is used to estimate the bandwidth of the communication line. In this embodiment, the communication speed detection unit 108 performs the same calculation, so the detection result of the communication speed detection unit 108 can be used as is.

The bandwidth estimation data generating unit 106 generates bandwidth estimation data to be used for bandwidth estimation by the other communication device 150. The bandwidth estimation data can be configured of known data of a certain length, for example.
In this embodiment, the bandwidth estimation data generating unit 106 generates the bandwidth estimation data in accordance with the timing determined by the bandwidth estimation timing determining unit 103 .

The transmitting unit 105 transmits the bandwidth estimation result generated by the bandwidth estimation unit 104 to another communication device 150. When the bandwidth estimation data generating unit 106 generates bandwidth estimation data, the transmitting unit 105 transmits the bandwidth estimation data in addition to the bandwidth estimation result.

(2) Operation of the Communication Apparatus 100 of the Present Embodiment The operation of the communication apparatus 100 of the present embodiment will be described with reference to FIG.
Note that the following operations not only indicate the communication method in communication device 100, but also indicate the processing procedure of a communication program executed by communication device 100. The order of these processes is not limited to the order shown in Fig. 6. In other words, the order may be changed as long as there is no constraint such as a relationship in which a certain step utilizes the result of the previous step.
The above applies not only to this embodiment, but also to other embodiments and modified examples.

The receiving unit 101 of the communication device 100 receives "data" from another communication device 150 via a communication line (S101).
The communication speed limit determination unit 102 determines whether a "speed limit" occurs due to an external factor, that is, a factor that does not depend on the communication environment of the communication line (S102).
When the communication speed limit determining section 102 determines that a speed limit has occurred, the bandwidth estimation timing determining section 103 determines the "timing" of bandwidth estimation (S103).
The bandwidth estimation unit 104 estimates the bandwidth of the communication line at the timing determined by the bandwidth estimation timing determination unit 103, and generates a bandwidth estimation result (S104).
The transmitting unit 105 transmits the bandwidth estimation result generated by the bandwidth estimating unit 104 to the other communication device 150 (S105).

An example of the operation of the communication device 100 of the present embodiment will be described with reference to FIG.
The period for determining whether a communication speed limit has been imposed is defined as a judgment window. Whether the communication speed is constant or not is determined based on the communication speed detected during the period defined by the judgment window. Since the communication speed is not constant during periods h and i, it is not determined that a speed limit has been imposed. However, it is assumed that the monthly communication volume exceeds a predetermined volume midway through period i.

In period j, the communication speed is constant and is within the range of the reference communication speed (128 kbps ±10%) specified in event A in Figure 5, so it is determined that a speed limit has occurred. Therefore, the reference timing (first time) in Figure 5 is read, and a thinning count of +3 is applied in period k.

In period k, a thinning count of +3 is applied, so that the bandwidth is estimated only once during the period in which the bandwidth is normally estimated four times. The communication speed detected in period k is within the range of the reference communication speed (128 kbps ±10%) specified in event A in Figure 5, so it is determined that a speed limit has occurred. Therefore, the reference timing (from the second time onwards) in Figure 5 is read, and a thinning count of +2 is applied in period l.

In period l, a total of +5 decimation times are applied (+3 plus +2), so that only one bandwidth estimation is performed during the period in which bandwidth estimation is normally performed six times. The communication speed detected in period l is within the range of the reference communication speed (128 kbps ±10%) specified in event A in Figure 5, so it is determined that a speed limit has occurred. Therefore, the reference timing (from the second time onwards) in Figure 5 is read, and a further +2 decimation time is applied in period m.

(3) Advantages of the Present Embodiment As described above, according to the communication device 100 of the present embodiment, when a speed limit occurs that is not dependent on the communication environment of the communication line, the timing of bandwidth estimation is reduced, so that the number of times the result of bandwidth estimation is transmitted can be reduced, and the resources of the transmission line among the communication lines of the communication device 100 can be effectively utilized. In addition, since the other communication device 150 can perform control to reduce the number of times that the data for bandwidth estimation is transmitted, the resources of the reception line among the communication lines can be effectively utilized.
Furthermore, according to the communication device 100 of this embodiment, the bandwidth estimation data is generated according to the timing determined by the bandwidth estimation timing determination unit 103, so that the number of times the bandwidth estimation data is transmitted can be reduced, and the resources of the transmission line among the communication lines can be effectively utilized.

(4) Modification of the Present Embodiment The communication speed detection unit 108 of the first embodiment described above detects the communication speed based on the data transmission time, data reception time, and data size. The communication speed detection unit 108 of the present modification detects the communication speed from a bandwidth estimation result estimated and transmitted by another communication device 150.

The communication speed detection unit 108 detects the bandwidth estimation result (corresponding to the “other party’s bandwidth estimation result”) estimated by the other communication device 150 from the bandwidth estimation result included in the data received by the receiving unit 101 by extracting it from the data.
That is, this modified example is the same as the first embodiment in that the communication speed detection unit 108 detects the communication speed of the communication line "based on the data" received by the receiving unit 101. However, the difference is that the communication speed detection unit 108 of the first embodiment measures and detects the communication speed of the receiving line, whereas the communication speed detection unit 108 of this modified example acquires and detects the communication speed of the transmitting line.

As in the first embodiment, the communication speed limit determination unit 102 determines that a speed limit has occurred when the communication speed detected by the communication speed detection unit 108 is "constant" and "matches" the reference communication speed.

As described above, according to the communication device 100 of this embodiment, in addition to the effects of the first embodiment, there is no need for the communication speed detection unit 108 to perform calculations to determine the communication speed, and the hardware resources of the communication device 100 can be effectively utilized.

3. Embodiment 2
In the first embodiment, the occurrence of a speed limit is determined by comparing the communication speed detected by the communication speed detection unit 108 with the reference communication speed stored in the storage unit 107. In this embodiment, the occurrence of a speed limit is determined by using the amount of data received by the receiving unit 101 and/or the amount of data transmitted by the transmitting unit 105. Note that only the parts that differ from the first embodiment will be described below, and the description of the first embodiment will be quoted for the configurations that are common to the first embodiment.

(1) Configuration of the Communication Apparatus 100 of the Present Embodiment The configuration of the communication apparatus 100 of the second embodiment will be described with reference to FIG.
In this embodiment, the communication speed limit determination unit 102 has a communication volume detection unit 109. The communication volume detection unit 109 detects the amount of data received by the receiving unit 101 and/or the amount of data transmitted by the transmitting unit 105. That is, it is sufficient for the communication volume detection unit 109 to detect any one of the reception volume, the transmission volume, or the sum of the reception volume and the transmission volume.

When the communication volume detection unit 109 detects the volume of data transmitted from the transmission unit 105, all data transmitted from the transmission unit 105 is the target. In other words, in addition to the bandwidth estimation result generated by the bandwidth estimation unit 104 and the bandwidth estimation data generated by the bandwidth estimation data generation unit 106, data transmitted from sensors and cameras connected to the communication device 100, and data transmitted from the ECU are also the target.

When the communication volume detection unit 109 detects the amount of data received from the receiving unit 101, all data received from the receiving unit 101 is the target. In other words, the target includes bandwidth estimation results generated by other communication devices 150, sensors and cameras connected to the communication device 100, and data received addressed to the ECU.

The communication speed limit determination unit 102 determines that a speed limit has occurred when the reception amount and/or transmission amount detected by the communication amount detection unit 109 exceeds a "predetermined amount". Whether to use the reception amount, transmission amount, or the total of the reception amount and transmission amount may be determined in light of the cause of the speed limit. For example, in the event A of the line 1 in FIG. 5, the communication speed is limited when the transmission and reception amount, i.e., the total of the reception amount and transmission amount, exceeds 6 GB in one month, so the communication amount detection unit 109 detects the total of the reception amount and transmission amount, and the communication speed limit determination unit 102 determines whether the total of the reception amount and transmission amount exceeds a predetermined amount. In addition, the cause of the speed limit may be specified as a union of multiple conditions. For example, the cause of the speed limit may be when the reception amount exceeds 6 GB in one month or when the transmission amount exceeds 10 GB in three days. In this way, time information may be included as the cause of the speed limit.
Here, the "predetermined amount" may be a fixed value or a variable value that varies depending on conditions. The "predetermined amount" may also include time information.

In the present embodiment, it is optional whether or not to provide the communication speed detection unit 108. In the first embodiment, the bandwidth estimation unit 104 estimates the bandwidth by estimating the communication speed, so the bandwidth estimation unit 104 uses the detection result of the communication speed detection unit 108 as is. In the present embodiment, if the communication speed detection unit 108 is not provided, the bandwidth estimation unit 104 executes an estimation of the communication speed. The method of estimating the communication speed can be the same as the method used by the communication speed detection unit 108 in the first embodiment.

(2) Advantages of the Present Invention As described above, according to the communication device 100 of the present invention, when a speed limit occurs that is not dependent on the communication environment of the communication line, the timing of bandwidth estimation is reduced, so that the number of times the bandwidth estimation result is transmitted can be reduced, and the resources of the transmission line among the communication lines can be effectively utilized. In addition, since the other communication device 150 can perform control to reduce the number of times that the bandwidth estimation data is transmitted, the resources of the reception line among the communication lines can be effectively utilized.
Furthermore, according to the communication device 100 of the present embodiment, the number of times the bandwidth estimation calculations themselves are performed is also reduced, so that the calculations required for bandwidth estimation can be reduced and hardware resources can be used effectively.
Furthermore, according to the communication device 100 of this embodiment, the bandwidth estimation data is generated according to the timing determined by the bandwidth estimation timing determination unit 103, so that the number of times the bandwidth estimation data is transmitted can be reduced, and the resources of the transmission line among the communication lines can be effectively utilized.

(3) Modification of the Present Embodiment The communication traffic detection unit 109 of the second embodiment described above detects the amount of data transmitted and received by the communication device 100 itself. The communication traffic detection unit 109 of the present modification acquires the communication traffic of the communication device 100 and other communication devices 150 from outside.

The communication traffic detection unit 109 acquires the communication traffic of the communication device 100 from an external communication traffic management server. For example, it queries the communication carrier server of the communication carrier with which the contract for use of the communication line has been concluded about the current communication traffic, and acquires the communication traffic as a response. The communication traffic may be any of the following, depending on the cause of the speed limit: the received traffic, the transmitted traffic, or the sum of the received and transmitted traffic. The communication traffic may be acquired periodically, or at any timing. If the response from the communication carrier server of the communication carrier includes information indicating whether or not the speed is limited, that information may be used as is. If the response from the communication carrier server of the communication carrier includes communication speed information after the speed limit has been imposed, that information may be used as is.

The speed limit may occur not only when the communication device 100 exceeds a predetermined communication volume, but also when another communication device 150 exceeds a predetermined communication volume. Therefore, the communication volume detection unit 109 may obtain the communication volume of the other communication device 150 from an external communication volume management server.

Then, as in the second embodiment, the communication speed limit determination unit 102 determines that a speed limit has occurred when the communication volume acquired by the communication volume detection unit 109 exceeds the "predetermined volume."

When the communication volume of another communication device 150 exceeds a predetermined volume, the bandwidth estimation timing determination unit 103 only needs to determine the bandwidth estimation timing when communication with the other communication device 150 is performed.

As described above, according to the communication device 100 of this embodiment, in addition to the effects of the second embodiment, it is not necessary for the communication volume detection unit 109 to perform calculations to determine the communication volume, and the hardware resources of the communication device 100 can be utilized effectively.
In addition, since it is possible to know not only when a predetermined communication volume has been exceeded in communication device 100 but also when a predetermined communication volume has been exceeded in another communication device 150, it is possible to identify whether the cause of the speed limit is the own device or another device and to determine the appropriate timing for bandwidth estimation.

4. Embodiment 3
The second embodiment is an embodiment in which the speed limit is caused by an excess of communication volume. The present embodiment is an embodiment in which the speed limit is caused by a temperature rise in the communication device 100. Note that only the parts that differ from the first embodiment will be described below, and the description of the first embodiment will be quoted for the configurations that are common to the first embodiment.

(1) Configuration of the Communication Apparatus 100 of the Present Embodiment The configuration of the communication apparatus 100 of the third embodiment will be described with reference to FIG.
In this embodiment, the communication speed limit determination unit 102 has a temperature detection unit 110. The temperature detection unit 110 detects the "temperature" of the communication device 100 itself or a component constituting the communication device 100, for example, a CPU or a communication module. The temperature may be detected using information that directly indicates the temperature, such as a directly measured temperature or the output of a device such as a thermocouple, or information that indirectly indicates the temperature, such as status information transmitted from a component constituting the communication device 100.
Here, "temperature" includes not only the temperature indicated in Celsius or Fahrenheit, but also information that indirectly indicates a temperature or a temperature range.

The communication speed limit determination unit 102 determines that a speed limit has occurred when the temperature detected by the temperature detection unit 110 exceeds a "predetermined temperature." For example, in the event B of the line 1 in Fig. 5, the communication speed is limited when the temperature of the communication module exceeds 60°C, so the temperature detection unit 110 detects the temperature, and the communication speed limit determination unit 102 determines whether the temperature exceeds the predetermined temperature.
Here, the "predetermined temperature" may be a fixed value or may be a variable value that varies depending on conditions.

In the present embodiment, it is optional whether or not to provide the communication speed detection unit 108. In the first embodiment, the bandwidth estimation unit 104 estimates the bandwidth by estimating the communication speed, so the bandwidth estimation unit 104 uses the detection result of the communication speed detection unit 108 as is. In the present embodiment, if the communication speed detection unit 108 is not provided, the bandwidth estimation unit 104 executes an estimation of the communication speed. The method of estimating the communication speed can be the same as the method used by the communication speed detection unit 108 in the first embodiment.

Note that an abnormality detection unit that detects abnormalities in parts that configure the communication device 100 may be provided instead of the temperature detection unit 110. The temperature detection unit 110 is an example of the abnormality detection unit. It is only necessary to determine in advance what type of abnormality is detected that will cause the device to transition to the degenerate mode.
In this embodiment, it is determined that the speed limit has occurred when the temperature exceeds a predetermined temperature, but if the degenerate mode is also set when the temperature falls below the predetermined temperature, it may be determined that the speed limit has occurred when the temperature falls below the predetermined temperature. For example, the degenerate mode may be set when the temperature falls outside the range of -30°C to 60°C.

(2) Advantages of the Present Invention As described above, according to the communication device 100 of the present invention, when a speed limit occurs that is not dependent on the communication environment of the communication line, the timing of bandwidth estimation is reduced, so that the number of times the bandwidth estimation result is transmitted can be reduced, and the resources of the transmission line among the communication lines can be effectively utilized. In addition, since the other communication device 150 can perform control to reduce the number of times that the bandwidth estimation data is transmitted, the resources of the reception line among the communication lines can be effectively utilized.
Furthermore, according to the communication device 100 of the present embodiment, the number of times the bandwidth estimation calculations themselves are performed is also reduced, so that the calculations required for bandwidth estimation can be reduced and hardware resources can be used effectively.
Furthermore, according to the communication device 100 of this embodiment, the bandwidth estimation data is generated according to the timing determined by the bandwidth estimation timing determination unit 103, so that the number of times the bandwidth estimation data is transmitted can be reduced, and the resources of the transmission line among the communication lines can be effectively utilized.

5. Embodiment 4
The fourth embodiment is an embodiment in which the rate limit occurs due to a temperature rise in the communication device 100. The present embodiment is an embodiment in which the rate limit occurs due to an input voltage of the communication device 100. Note that only the parts that differ from the first embodiment will be described below, and the description of the first embodiment will be quoted for the configuration that is common to the first embodiment.

(1) Configuration of the Communication Apparatus 100 of the Present Embodiment The configuration of the communication apparatus 100 of the fourth embodiment will be described with reference to FIG.
In this embodiment, the communication speed limit determination unit 102 has a voltage detection unit 111. The voltage detection unit 111 detects the "input voltage" of the communication device 100 itself or a component constituting the communication device 100, for example, a semiconductor module. The input voltage may be detected using information that directly indicates the input voltage, such as a directly measured voltage value or the output of a power supply IC, or information that indirectly indicates the input voltage, such as status information transmitted from a component constituting the communication device 100.
Here, the "input voltage" includes information that directly indicates the input voltage as well as information that indirectly indicates the input voltage.

The communication speed limit determination unit 102 determines that a speed limit has occurred when the input voltage detected by the voltage detection unit 111 falls below a "predetermined input voltage." For example, in the case of event C of line 1 in Fig. 5, the communication speed is limited when the input voltage of the semiconductor module falls below 3 V, so the voltage detection unit 111 detects the input voltage, and the communication speed limit determination unit 102 determines whether the input voltage falls below the predetermined input voltage.
Here, the "predetermined input voltage" may be a fixed value or may be a variable value that varies depending on conditions.

In the present embodiment, it is optional whether or not to provide the communication speed detection unit 108. In the first embodiment, the bandwidth estimation unit 104 estimates the bandwidth by estimating the communication speed, so the bandwidth estimation unit 104 uses the detection result of the communication speed detection unit 108 as is. In the present embodiment, if the communication speed detection unit 108 is not provided, the bandwidth estimation unit 104 executes an estimation of the communication speed. The method of estimating the communication speed can be the same as the method used by the communication speed detection unit 108 in the first embodiment.

Note that an abnormality detection unit that detects abnormalities in parts that configure the communication device 100 may be provided instead of the voltage detection unit 111. The voltage detection unit 111 is an example of the abnormality detection unit. It is only necessary to determine in advance what type of abnormality is detected that will cause the device to transition to the degenerate mode.
In this embodiment, it is determined that the speed limit has occurred when the input voltage falls below a predetermined value, but if the degenerate mode is also entered when the input voltage exceeds the predetermined value, it may be determined that the speed limit has occurred when the input voltage exceeds the predetermined value. For example, the degenerate mode may be entered when the input voltage falls outside the range of 3 V to 4 V.

(2) Advantages of the Present Invention As described above, according to the communication device 100 of the present invention, when a speed limit occurs that is not dependent on the communication environment of the communication line, the timing of bandwidth estimation is reduced, so that the number of times the bandwidth estimation result is transmitted can be reduced, and the resources of the transmission line among the communication lines can be effectively utilized. In addition, since the other communication device 150 can perform control to reduce the number of times that the bandwidth estimation data is transmitted, the resources of the reception line among the communication lines can be effectively utilized.
Furthermore, according to the communication device 100 of the present embodiment, the number of times the bandwidth estimation calculations themselves are performed is also reduced, so that the calculations required for bandwidth estimation can be reduced and hardware resources can be used effectively.
Furthermore, according to the communication device 100 of this embodiment, the bandwidth estimation data is generated according to the timing determined by the bandwidth estimation timing determination unit 103, so that the number of times the bandwidth estimation data is transmitted can be reduced, and the resources of the transmission line among the communication lines can be effectively utilized.

6. Relationship between embodiment 1, embodiment 2, embodiment 3, and embodiment 4 In embodiment 1, the communication speed limit determination unit 102 includes a communication speed detection unit 108, in embodiment 2, the communication speed limit determination unit 102 includes a communication volume detection unit 109, in embodiment 3, the communication speed limit determination unit 103 includes a temperature detection unit 110, and in embodiment 4, the communication speed limit determination unit 103 includes a voltage detection unit 111. These embodiments and their modified examples can be used alone or in any combination. For example, the communication device 100 in FIG. 2 can be understood as having all the configurations of embodiment 1, embodiment 2, embodiment 3, and embodiment 4.

In the third and fourth embodiments, examples of the anomaly detection unit have been described in which the unit detects temperature anomalies and input voltage anomalies, respectively, but the unit may be configured to detect other anomalies. For example, the unit may be configured to detect vibrations, humidity, or ambient noise.

7. Embodiment 5
The configuration of the communication device 200 of the fifth embodiment will be described with reference to Fig. 8. This differs from Fig. 2, which shows the configurations of the first to fourth embodiments, in that the receiving unit 201 has a first receiving unit 211 connected to the first communication line and a second receiving unit 212 connected to the second communication line, and the transmitting unit 205 has a first transmitting unit 213 connected to the first communication line and a second transmitting unit 214 connected to the second communication line.
Also, the communication speed limit determination unit 202, the bandwidth estimation timing determination unit 203, the bandwidth estimation unit 204, the bandwidth estimation data generation unit 206, the communication speed detection unit 208, and the communication volume detection unit 209 differ in that they process the first communication line and the second communication line, respectively.

The first and second communication lines may have different communication methods, or may have the same communication method but have different communication contracts, such as different telecommunications carriers, communication providers, and communication fee structures and speed limits. Different telephone numbers may be assigned to the first and second communication lines. The first and second communication lines may be dedicated data communication lines that do not support voice calls, or may be dedicated lines using a VPN (Virtual Private Network).
The communication destination of the first communication line and the communication destination of the second communication line may be different communication devices. The same applies to the sixth embodiment.

When the communication speed limit determination unit 202 determines that a speed limit has occurred on the first communication line, the bandwidth estimation unit 204 estimates the bandwidth of the first communication line at the timing determined by the bandwidth estimation timing determination unit 203 to generate a bandwidth estimation result. The communication speed limit determination unit 202 can make a determination by at least one of the methods of embodiments 1 to 4.

The second transmission unit 214 of the transmission unit 205, which is connected to the second communication line, transmits the bandwidth estimation result of the first communication line estimated by the bandwidth estimation unit 204 to the other communication device 150.

As described above, according to this embodiment, the bandwidth estimation result is transmitted via a communication line other than the communication line on which it is determined that a speed limit has occurred, so that the bandwidth estimation result can be transmitted without being affected by the speed limit, and the communication volume on the communication line on which the speed limit has occurred can be reduced.
In particular, this is particularly effective when a speed limit is imposed on one communication line as a result of exceeding a certain communication volume in a certain period of time. For example, when multiple communication paths are to be established from the viewpoint of communication line redundancy, more data that requires redundant transmission can be transmitted to the communication line where the speed limit has occurred.

8. Embodiment 6
The configuration of the communication device 200 of the sixth embodiment will be described with reference to Fig. 8. In addition to the differences described in the fifth embodiment , the sixth embodiment differs from the configurations of the communication device 200 of the first to fourth embodiments in that a process for the case where the bandwidth estimations of the first and second communication lines overlap in time is added as a function of the bandwidth estimation timing determination unit 203.

When the communication speed limit determination unit 202 determines that a speed limit has occurred, the bandwidth estimation timing determination unit 203 determines the timing of bandwidth estimation for the communication line in which the speed limit has occurred, and when the bandwidth estimations for the first communication line and the second communication line in the bandwidth estimation unit 204 overlap in time, the bandwidth estimation timing for the first communication line and/or the second communication line is changed.

The determination by the communication speed limit determination unit 202 can be made by at least one of the methods according to the first to fourth embodiments.
The timing of the bandwidth estimation performed by the bandwidth estimation timing determination unit 203 can be determined by the method described in the first embodiment.
The timing of bandwidth estimation may be changed for either the first communication line or the second communication line, or for both the first communication line and the second communication line.

Specific examples of changing the timing of bandwidth estimation will be described in the following Examples 1 to 4.
(1) Example 1
The operation of the communication device 200 according to the first embodiment of the present invention will be described with reference to FIG. 9 and FIG.
9, for example, when the temperature of the communication module of the communication device 200 rises, the communication speed limit determination unit 202 determines that a speed limit has been applied to the first and second communication lines. Then, the bandwidth estimation timing determination unit 203 determines the timing of bandwidth estimation for the first and second communication lines. However, when the timing of bandwidth estimation for the first and second communication lines overlaps in time, the load on the software and hardware (e.g., a CPU) that realizes the function of the bandwidth estimation unit 204 is concentrated in time.

Therefore, the bandwidth estimation timing determination unit 203 shifts the timing of the bandwidth estimation of the first communication line by a predetermined time. For example, as shown in FIG. 10, the timing of the bandwidth estimation is shifted by making it one time shorter than the initial number of times that would normally be thinned out.

Whether the timings of the bandwidth estimations overlap in time can be determined by the bandwidth estimation timing determination unit 203 itself through calculation, but it may also be detected by measuring the CPU load. The same applies to other embodiments.

In this embodiment, the timing of the bandwidth estimation is changed for the first communication line because the time when the speed limit was determined to have occurred is later for the first communication line than for the second communication line. Alternatively, the bandwidth estimation timing for the second communication line may be changed midway. Of course, the bandwidth estimation timing for both communication lines may be changed. The same applies to the other embodiments.

In this embodiment, the timing of bandwidth estimation is shifted by changing the number of times the initial thinning is performed, but a predetermined time weight may also be set.

In addition, in this embodiment, a case has been described in which the periods of the bandwidth estimation timing of the first communication line and the second communication line match, but the periods do not necessarily have to match. For example, when the number of times the first communication line is thinned out is 1 and when the number of times the second communication line is thinned out is 3, the bandwidth estimation timing of the second communication line will always match the bandwidth estimation timing of the first communication line, and the processing of this embodiment is also effective in this case.

As described above, according to this embodiment, it is possible to prevent the load on software and hardware from being concentrated over time when a speed limit occurs. Specifically, it is possible to smooth out the load on software and hardware by utilizing the free time in bandwidth estimation that occurs when a speed limit occurs.

(2) Example 2
The operation of the communication device 200 according to the second embodiment of the present invention will be described with reference to FIG.
Fig. 11 shows only the portion corresponding to the portion showing the timing of the bandwidth estimation process in Fig. 9 and Fig. 10. In the case of Fig. 11, when the bandwidth estimation timing decision unit 202 sets the number of decimation times of the bandwidth estimation of the first communication line to 2 (i.e., the estimation interval is tripled because the estimation is performed once every three times) and the number of decimation times of the bandwidth estimation of the second communication line to 3 (i.e., the estimation interval is quadrupled because the estimation is performed once every four times), the least common multiple of the estimation intervals is 12, so that the timing of the bandwidth estimation overlaps in time once every 12 times.

The bandwidth estimation timing determination unit 202 therefore changes the timing of bandwidth estimation for one of the communication lines for the bandwidth estimation processes where the timings of the bandwidth estimations overlap in time. In this embodiment, the bandwidth estimation timing for the second communication line where a speed limit is subsequently generated is performed after the bandwidth estimation for the first communication line only in the portion where the bandwidth estimation timing for the second communication line overlaps with the bandwidth estimation timing for the first communication line.

As described above, according to this embodiment, it is possible to prevent the load on software and hardware from being concentrated over time when a speed limit occurs. Specifically, it is possible to smooth out the load on software and hardware by utilizing the free time in bandwidth estimation that occurs when a speed limit occurs.

(3) Example 3
The operation of the communication device 200 according to the third embodiment of the present invention will be described with reference to FIG.
The bandwidth estimation timing determination unit 202 of the second embodiment changes the timing of the bandwidth estimation of one of the communication lines only at the timing when the bandwidth estimations overlap in time based on the least common multiple of the estimation interval of the first communication line and the estimation interval of the second communication line. In this embodiment, in order to minimize the frequency of changing the timing of the bandwidth estimation of one of the communication lines in advance, the timing of the bandwidth estimation of the communication lines is changed so that the least common multiple of the estimation intervals becomes large.

The bandwidth estimation timing determination unit 202 determines the least common multiple of the estimation intervals of the first communication line and the second communication line based on the determined timing. For example, as in the second embodiment, if the number of times that the bandwidth estimation of the first communication line is thinned out is set to 2 (i.e., the estimation interval is tripled because the estimation is performed once every three times) and the number of times that the bandwidth estimation of the second communication line is thinned out is set to 3 (i.e., the estimation is performed once every four times, so the estimation interval is quadrupled), the least common multiple of the estimation intervals is 12.

Then, the bandwidth estimation timing determination unit 202 calculates the combination of the number of times of thinning out that has the largest common multiple when the number of times of thinning out is changed within the range of ±1 for each of the first communication line and the second communication line 2. In this case, as shown in FIG. 12, when 1 is added to the number of times of thinning out for the first communication line and 1 is added to the number of times of thinning out for the second communication line, the least common multiple of the estimation intervals becomes 20, which is the largest. Therefore, the bandwidth estimation timing determination unit 202 changes the number of times of thinning out for the bandwidth estimation of the first communication line to 3 and the number of times of thinning out for the bandwidth estimation of the second communication line to 4.

As another example, if the number of decimations in the bandwidth estimation of the first communication line is 6 (i.e., the estimation interval is 7 times because the estimation is performed once every 7 times) and the number of decimations in the bandwidth estimation of the second communication line is 2 (i.e., the estimation interval is 3 times because the estimation is performed once every 3 times), the least common multiple of the estimation intervals is 21. Then, the bandwidth estimation timing determination unit 202 calculates the combination of the number of decimations that has the largest least common multiple when the number of decimations is changed within the range of ±1 for each of the first communication line and the second communication line 2. In this case, as shown in FIG. 12, when the number of decimations in the first communication line is left unchanged and the number of decimations in the second communication line is added by 1, the least common multiple of the estimation intervals becomes the largest, 28. Therefore, the bandwidth estimation timing determination unit 202 keeps the number of decimations in the bandwidth estimation of the first communication line at 6 and changes the number of decimations in the bandwidth estimation of the second communication line to 3.

In this embodiment, the number of times the first communication line and the second communication line are thinned out is changed within a range of ±1, but this combination is not limiting. For example, the longest allowable bandwidth estimation interval may be set, and the number of times the thinning out may be changed within this range. The longest allowable bandwidth estimation interval may be determined based on the longest time allowed to detect that an event involving a speed limit has been resolved, for example.

This embodiment may be combined with embodiment 2 to change the timing of communication line bandwidth estimation.

As described above, according to this embodiment, it is possible to prevent the load on software and hardware from being concentrated over time when a speed limit occurs. Specifically, by changing the least common multiple of the estimation intervals to a larger value, it is possible to smooth out the load on software and hardware.

(4) Example 4
The operation of the communication device 200 according to the fourth embodiment of the present invention will be described with reference to FIG.
The bandwidth estimation timing determination unit 202 of the third embodiment changes the timing of the bandwidth estimation of the communication line so that the least common multiple of the estimation intervals becomes large. In this embodiment, the estimation intervals are changed to have a larger least common multiple as in the third embodiment, but the timing of the bandwidth estimation of the communication line is changed in consideration of the degree of change in the estimation intervals.

The bandwidth estimation timing determination unit 202 determines the least common multiple of the estimation intervals of the first communication line and the second communication line based on the determined timing. For example, as in the second and third embodiments, if the number of times that the bandwidth estimation of the first communication line is thinned out is set to 2 (i.e., the estimation interval is tripled because the estimation is performed once every three times) and the number of times that the bandwidth estimation of the second communication line is thinned out is set to 3 (i.e., the estimation is performed once every four times, so the estimation interval is quadrupled), the least common multiple of the estimation intervals is 12.

Then, the bandwidth estimation timing determination unit 202 calculates an evaluation value based on the following formula when the number of times of thinning to be added is changed in the range of 0 to 10 for each of the first communication line and the second communication line 2.

Evaluation value = (Least common multiple after change - Least common multiple before change)
÷ (change in the number of culls of the first communication line + change in the number of culls of the second communication line)

The numerator represents the degree of change in the least common multiple, and the evaluation value increases when the least common multiple is changed to one that results in a larger estimation interval.
The numerator represents the degree of change in the thinning number, and the closer it is to the initially determined thinning number, the higher the evaluation value.
The upper limit of the range of the number of times of thinning out is the longest allowable bandwidth estimation interval.

In this case, as shown in FIG. 13, the evaluation value is highest when 10 is added to the number of times of thinning out for the first communication line and when 10 is added to the number of times of thinning out for the second communication line. Therefore, the bandwidth estimation timing determination unit 202 changes the number of times of thinning out for the bandwidth estimation of the first communication line to 12 and the number of times of thinning out for the bandwidth estimation of the second communication line to 13.

As described above, according to this embodiment, it is possible to prevent the load on software and hardware from being concentrated over time when a speed limit occurs. Specifically, the load on software and hardware can be smoothed by taking into account the least common multiple of the estimation intervals and the degree of change in the estimation interval.

9. Summary The features of the communication devices and the like in each embodiment of the present invention have been described above.
The terms used in each embodiment are merely examples and may be replaced with terms having the same meaning or functions.

The block diagrams used to explain the embodiments classify and organize the device configuration by function. The blocks showing each function are realized by any combination of hardware or software. In addition, since they show functions, such block diagrams can also be understood as disclosures of method inventions and program inventions that realize the methods.

The order of the processes, flows, and blocks that can be understood as methods described in each embodiment may be changed, as long as there are no constraints such as a relationship in which one step uses the results of another step that precedes it.

Unless otherwise specified in the claims, the communication device of the present invention may be for vehicle use, and also includes dedicated or general-purpose communication devices other than for vehicle use.

Moreover, examples of the form of the communication device of the present invention include a semiconductor element, an electronic circuit, a module, and a microcomputer.
Examples of semi-finished products include an electronic control unit (ECU) and a system board.
Finished product forms include mobile phones, smartphones, tablets, personal computers (PCs), workstations, and servers.
Other examples include devices with communication functions, such as car navigation systems.

It is assumed that the communication device of the present invention will be used for the purpose of providing various services. In providing such services, the communication device of the present invention will be used, the method of the present invention will be used, and/or the program of the present invention will be executed.

In addition, the present invention can be realized not only by dedicated hardware having the configuration and functions described in each embodiment, but also as a combination of a program for implementing the present invention recorded on a recording medium such as a memory or hard disk, and general-purpose hardware having a dedicated or general-purpose CPU and memory capable of executing the program.

The program for the communication device of the present invention, which is stored in a non-transitive, substantial recording medium (e.g., an external storage device (hard disk, USB memory, CD/BD, etc.) or an internal storage device (RAM, ROM, etc.)) of dedicated or general-purpose hardware, can also be provided to the dedicated or general-purpose hardware via the recording medium, or via a communication line from a server without using a recording medium. This makes it possible to always provide the latest functions through program upgrades.

The communication device of the present invention has been described assuming that it is primarily a communication device mounted on an automobile, but it can be realized in various communication devices that perform bandwidth estimation. In addition, it can be applied not only to the application layer level, but also to lower layers in the OSI 7-layer reference model.

100, 200 Communication device, 101 Receiving unit, 102 Communication speed limit determination unit, 103 Bandwidth estimation timing determination unit, 104 Bandwidth estimation unit, 105 Transmitting unit, 106 Bandwidth estimation data generation unit, 107 Storage unit, 108 Communication speed detection unit, 109 Communication volume detection unit, 110 Temperature detection unit, Voltage detection unit 111

Claims (19)

A communication device that communicates with another communication device via a communication line,
A receiving unit (101) for receiving data from the other communication device;
A communication speed limit determination unit (102) that determines the occurrence of a speed limit that is not dependent on the communication environment of the communication line;
a bandwidth estimation timing determination unit (103) that, when it is determined by the communication speed limit determination unit that the speed limit has occurred, determines a timing for bandwidth estimation that is less frequent per unit time than when the speed limit has not occurred ;
a bandwidth estimation unit (104) for estimating a bandwidth of the communication line at the timing and generating a bandwidth estimation result;
A communication device (100) comprising: a transmission unit (105) that transmits the bandwidth estimation result to the other communication device. Further, a bandwidth estimation data generating unit (106) is provided for generating bandwidth estimation data to be used by the other communication device for bandwidth estimation,
The transmission unit transmits the bandwidth estimation data in addition to the bandwidth estimation result.
The communication device according to claim 1. Further, a storage unit (107) is provided for storing a reference communication speed, which is a communication speed determined when an event involving the speed limit occurs,
The communication speed limit determination unit has a communication speed detection unit (108) that detects the communication speed of the communication line based on the data,
the communication speed limit determination unit determines that the speed limit has been applied when the communication speed detected by the communication speed detection unit is constant and coincides with the reference communication speed.
The communication device (100) of claim 1. The storage unit further stores a reference timing corresponding to the reference communication speed,
the bandwidth estimation timing determination unit reads out from the storage unit the reference timing corresponding to the communication speed detected by the communication speed detection unit, and sets the reference timing as the timing;
The communication device according to claim 3 . The reference timing is defined by a decimation count, which is the number of times the bandwidth estimation is decimated.
The communication device according to claim 4 . The reference timing is such that the number of times of thinning out is increased as the duration of the speed limit becomes longer.
The communication device according to claim 5 . the communication speed detection unit detects the communication speed of the communication line based on data that is larger than a predetermined data size among the data.
The communication device according to claim 3 . Further, a storage unit (107) is provided for storing a reference communication speed, which is a communication speed determined when an event involving the speed limit occurs,
The communication speed limit determination unit has a communication speed detection unit (108) that detects a peer bandwidth estimation result included in the data,
the communication speed limit determination unit determines that the speed limit has occurred when the communication speed indicated by the peer bandwidth estimation result is constant and coincides with the reference communication speed.
The communication device (100) of claim 1. The communication speed limit determination unit has a communication volume detection unit (109) that detects the amount of data received by the receiving unit and/or the amount of data transmitted by the transmitting unit,
the communication speed limit determination unit determines that the speed limit has occurred when the reception amount and/or the transmission amount exceeds a predetermined amount.
The communication device (100) of claim 1. The communication speed limit determination unit has a communication traffic detection unit (109) that acquires communication traffic of the communication device or the other communication device from an external communication traffic management server,
The communication speed limit determination unit determines that the speed limit has occurred when the communication volume exceeds a predetermined volume.
The communication device (100) of claim 1. The communication speed limit determination unit has a temperature detection unit (110) that detects the temperature of the communication device itself or a component that constitutes the communication device,
the communication speed limit determination unit determines that the speed limit has occurred when the temperature exceeds a predetermined temperature.
The communication device (100) of claim 1. The communication speed limit determination unit has a temperature detection unit (110) that detects the temperature of the communication device itself or a component that constitutes the communication device,
the communication speed limit determination unit determines that the speed limit has occurred when the temperature is lower than a predetermined temperature.
A communication device (100) according to claim 1 or 11 . The communication speed limit determination unit has a voltage detection unit (111) that detects an input voltage input to the communication device itself or a component that constitutes the communication device,
the communication speed limit determination unit determines that the speed limit has occurred when the input voltage falls below a predetermined input voltage.
The communication device (100) of claim 1. The communication speed limit determination unit has a voltage detection unit (111) that detects an input voltage input to the communication device itself or a component that constitutes the communication device,
the communication speed limit determination unit determines that the speed limit has occurred when the input voltage exceeds a predetermined input voltage.
A communication device (100) according to claim 1 or 13 . A communication device that communicates with another communication device via a first communication line and a second communication line, the first communication line and the second communication line being a plurality of communication lines,
When the communication speed limit determination unit (202) determines that the speed limit of the first communication line has occurred, the transmission unit (205, 214) transmits the bandwidth estimation result via the second communication line.
The communication device (200) of claim 1. A communication device that communicates with another communication device via a first communication line and a second communication line, the first communication line and the second communication line being a plurality of communication lines,
the bandwidth estimation timing decision unit (203), when it is determined that the speed limit has occurred in the communication speed limit determination unit (202), determines a timing of bandwidth estimation of the communication line in which the speed limit has occurred, and, when the bandwidth estimations of the first communication line and the second communication line overlap in time, changes the timing of bandwidth estimation of the first communication line and/or the second communication line.
The communication device (200) of claim 1. The communication device is mounted on a mobile object.
A communication device according to any one of claims 1 to 16 . A communication method executed by a communication device that communicates with another communication device via a communication line, comprising:
Receiving data from the other communication device (S101);
Determining whether a speed limit occurs that is not dependent on the communication environment of the communication line (S102);
When it is determined that the speed limit has occurred, a bandwidth estimation timing that is less frequent per unit time than when the speed limit has not occurred is determined (S103);
Estimating the bandwidth of the communication line at the timing to generate a bandwidth estimation result (S104);
Transmitting the bandwidth estimation result to the other communication device (S105);
Communication methods. A communication program executable by a communication device that communicates with another communication device via a communication line,
Receiving data from the other communication device (S101);
Determining whether a speed limit occurs that is not dependent on the communication environment of the communication line (S102);
When it is determined that the speed limit has occurred, a bandwidth estimation timing that is less frequent per unit time than when the speed limit has not occurred is determined (S103);
Estimating the bandwidth of the communication line at the timing to generate a bandwidth estimation result (S104);
Transmitting the bandwidth estimation result to the other communication device (S105);
Communications program.