JP2023124386A - Information processing device, information processing method, and program - Google Patents

Abstract

To provide a technique that allows a reduction of costs required to control an output level.SOLUTION: An information processing device includes: an acquisition unit that obtains a first output level of a transmission signal at a first time and a second output level of a transmission signal at a second time that comes after the first time; an initial value determination unit that determines an initial value of the amount of attenuation of the transmission signal based on the first output level and the second output level; and a function control unit that activates an automatic control operation in which a first amount of attenuation of a first transmission signal is adjusted based on the initial value and also a second amount of attenuation of a second transmission signal that is transmitted after the first transmission signal is adjusted according to an output level of a third transmission signal that is transmitted before the second transmission signal.SELECTED DRAWING: Figure 1

Description

The present invention relates to an information processing device, an information processing method, and a program.

2. Description of the Related Art In recent years, there has been known a technique for controlling the output level of a signal transmitted by a wireless communication device so that the output level is kept constant. For example, a technique for controlling the output level based on the temperature detected by a temperature sensor has been disclosed (see Patent Document 1, for example).

JP 2010-74742 A

However, when the temperature sensor is used to control the output level, the provision of the temperature sensor is costly.

Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a technique capable of reducing the cost required for controlling the output level.

In order to solve the above problem, according to one aspect of the present invention, a first output level of a transmission signal at a first time and a first output level of a transmission signal at a second time later than the first time an initial value specifying unit that specifies an initial value of attenuation of a transmission signal based on the first output level and the second output level; and a first A first attenuation amount of a transmission signal is adjusted based on the initial value, and a second attenuation amount of a second transmission signal transmitted after the first transmission signal is adjusted from the second transmission signal. and a function control unit that activates an automatic control operation that adjusts according to the output level of a third transmission signal that has been transmitted previously.

The function control unit stops the automatic control operation, and the acquisition unit acquires the first output level and the second output level in a state where the automatic control operation is stopped, and controls the function. The unit may activate the automatic control action based on the initial value being specified.

The automatic control operation may include controlling to increase the attenuation amount when the output level of the third transmission signal is higher than a specified output level.

The automatic control operation may include controlling to decrease the attenuation amount when the output level of the third transmission signal is lower than a specified output level.

The initial value specifying unit may subtract the second output level from the first output level to calculate a difference, and specify an attenuation amount corresponding to the difference as the initial value.

The greater the difference, the greater the attenuation corresponding to the difference.

Further, according to an aspect of the present invention, a first output level of a transmission signal at a first time and a second output level of a transmission signal at a second time after the first time are obtaining, specifying an initial value of attenuation of the transmission signal based on the first output level and the second output level, and determining the first attenuation of the first transmission signal to the Adjusting based on an initial value and adjusting a second attenuation amount of a second transmission signal transmitted after the first transmission signal to a third transmission transmitted before the second transmission signal and activating an automatic control action that adjusts in response to the output level of the signal.

Further, according to an aspect of the present invention, a computer is configured to have a first output level of a transmission signal at a first time and a second output level of a transmission signal at a second time after the first time. an acquisition unit that acquires a level, an initial value specifying unit that specifies an initial value of attenuation of a transmission signal based on the first output level and the second output level, and an initial value of the first transmission signal Adjusting a first attenuation amount based on the initial value, and adjusting a second attenuation amount of a second transmission signal transmitted after the first transmission signal before the second transmission signal A program functioning as an information processing apparatus is provided, which includes a function control unit that activates an automatic control operation that adjusts according to the output level of a transmitted third transmission signal.

As described above, according to the present invention, it is possible to reduce the cost required for controlling the output level.

FIG. 4 is a block diagram showing a functional configuration example of a communication device related to a general output control method; 4 is a graph showing temperature characteristics of output level; 1 is a block diagram showing an example of functional configuration of a communication device according to an embodiment of the present invention; FIG. 4 is a block diagram showing a detailed configuration example of a monitoring unit; FIG. FIG. 10 is a diagram showing an example of output levels of a burst transmission signal by output control according to a comparative example; FIG. 4 is a diagram showing temporal changes in the output level of test radio waves according to the embodiment of the present invention; 4 is a graph showing temporal changes in the output level of a general DSRC radio device in a state where ALC control operation by DVATT is stopped; 4 is a flow chart showing the operation of the output control method by the communication device according to the embodiment of the present invention; FIG. 4 is a diagram showing an example of output levels of operating radio waves by output control according to the embodiment of the present invention;

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In the present specification and drawings, constituent elements having substantially the same functional configuration are denoted by the same reference numerals, thereby omitting redundant description.

In addition, in this specification and drawings, a plurality of components having substantially the same functional configuration are distinguished by attaching different numerals after the same reference numerals. In addition, similar components in different embodiments are distinguished from each other by using the same reference numerals followed by different alphabets. However, when there is no particular need to distinguish between a plurality of constituent elements having substantially the same functional configuration, only the same reference numerals are used.

[Description of overview]
Next, an outline of an embodiment of the present invention will be described.

2. Description of the Related Art In recent years, there has been known a method of controlling the output level of a signal transmitted by a wireless communication device so that the output level is kept constant (hereinafter also referred to as “output level control method”). First, a general output control method will be briefly described with reference to FIGS. 1 and 2. FIG.

FIG. 1 is a block diagram showing a functional configuration example of a communication device related to a general output control method. As shown in FIG. 1, a communication device 80 according to a general output control method includes an RF (Radio Frequency) transmission circuit 810, a DVATT (variable attenuator) 820, an amplifier 830, a detection circuit 840, an output section 860 , an AD (Analog-Digital) converter 870 , and a control section 880 .

RF transmission circuit 810 generates an RF signal and outputs the generated RF signal to DVATT 820 as a transmission signal. DVATT 820 attenuates the transmission signal input from RF transmission circuit 810 under the control of monitoring section 881 . Amplifier 830 amplifies the transmission signal after attenuation by DVATT 820 . The detection circuit 840 measures the output level of the transmission signal by detection. The output unit 860 outputs the transmission signal whose output level has been measured.

The AD converter 870 converts the analog format output level into a digital format output level and outputs the digital format output level to the control unit 880 .

The control unit 880 has a monitoring unit 881 and a storage unit 882 . The storage unit 882 stores data necessary for calculation by the monitoring unit 881 . The monitoring unit 881 performs ALC (Automatic Level Control) control (automatic control) so that the output level is kept constant. Here, the ALC control can mean comparing the output level input from the AD converter 870 and the prescribed output level stored in the storage unit 882, and controlling the DVATT 820 according to the comparison result.

For example, when the output level input from the AD converter 870 is higher than the specified output level, the monitoring section 881 controls the DVATT 820 to increase the attenuation of the transmission signal by the DVATT 820 . On the other hand, when the output level input from the AD converter 870 is lower than the specified output level, the monitoring section 881 controls the DVATT 820 to reduce the attenuation of the transmission signal by the DVATT 820 . ALC control can be realized in this way.

FIG. 2 is a graph showing temperature characteristics of the output level. As shown in FIG. 2, generally, the lower the ambient temperature, the higher the output level. As an example, when the communication device 80 starts transmitting immediately after the communication device 80 is activated, the substrate temperature is low, so the output level tends to increase. On the other hand, the higher the ambient temperature, the lower the output level. Therefore, in actual operation, it is desirable that the output level of the transmission signal output from the wireless device 80 is controlled to be constant.

Therefore, a technique for controlling the output level based on the temperature detected by the temperature sensor has been disclosed (see, for example, Japanese Unexamined Patent Application Publication No. 2002-100003).

More specifically, in this technology, if the temperature is detected when the amplifier device starts up, and if a control value corresponding to the detected temperature and the transmission frequency is stored in a memory, the transmission signal is controlled by the variable attenuator according to the control value. Sets the amount of attenuation. On the other hand, if the control value corresponding to the detected temperature and transmission frequency is not stored in the memory, a predetermined control value is output to the variable attenuator as an initial value, and the output level is stabilized at the predetermined output level. A control value is written in memory in association with the transmission frequency and the temperature.

However, such a technique requires a temperature sensor for detecting the temperature when the amplifying device starts up. Therefore, as with such techniques, it is costly to provide the temperature sensor. Therefore, in the embodiments of the present invention, a technology capable of reducing the cost required for controlling the output level will be mainly described.

The outline of the embodiment of the present invention has been described above.

[Details of embodiment]
Next, details of embodiments of the present invention will be described. As an example, the communication device according to the embodiment of the present invention can be applied to a DSRC (Dedicated Short-Range Communications) wireless communication device.

Examples of DSRC wireless communication devices include ETC (electronic Toll Collection System), VICS (registered trademark) (Vehicle Information and Communication System), and RSU (Road Side Unit). However, the type of device to which the communication device according to the embodiment of the present invention is applied is not limited.

(Description of configuration)
FIG. 3 is a block diagram showing a functional configuration example of the communication device according to the embodiment of the present invention. As shown in FIG. 3, the communication device 10 according to the embodiment of the present invention includes an RF transmission circuit 110, a DVATT 120, an amplifier 130, a detection circuit 140, an output section 160, an AD converter 170, a control section 180.

RF transmission circuit 110 generates an RF signal and outputs the generated RF signal to DVATT 120 as a transmission signal. DVATT 120 attenuates the transmission signal input from RF transmission circuit 110 under the control of monitoring section 181 . Amplifier 130 amplifies the transmission signal after attenuation by DVATT 120 . The detection circuit 140 measures the output level of the transmission signal by detection. The output unit 160 outputs the transmission signal whose output level has been measured.

The AD converter 170 converts the analog format output level into a digital format output level and outputs the digital format output level to the control unit 180 .

The control unit 180 includes a monitoring unit 181 , a storage unit 182 , an acquisition unit 183 , an initial value identification unit 184 and a function control unit 185 .

The control unit 180 includes an arithmetic device (processor), and its function can be realized by executing a program stored in a memory by the arithmetic device. At this time, a computer-readable recording medium recording the program may also be provided.

For example, the control unit 180 is configured by an FPGA (Field-Programmable Gate Array), and its function can be realized by executing circuit configuration data stored in a memory by an LSI (Large Scale Integrated Circuit). Alternatively, the control unit 180 may be composed of dedicated hardware, or may be composed of a combination of multiple pieces of hardware.

The storage unit 182 stores data required for calculations by the monitoring unit 181 , acquisition unit 183 , initial value identification unit 184 and function control unit 185 .

The monitoring unit 181 performs ALC control so that the output level is kept constant. More specifically, the monitoring unit 181 compares the output level input from the AD converter 170 and the prescribed output level stored in the storage unit 182 . The monitoring unit 181 controls the DVATT 120 according to the comparison result.

For example, the monitoring unit 181 increases the attenuation of the transmission signal by the DVATT 120 when the output level input from the AD converter 170 is higher than the specified output level. On the other hand, when the output level input from the AD converter 170 is lower than the specified output level, the monitoring section 181 reduces the amount of attenuation of the transmission signal by the DVATT 120 .

The control unit 180 is configured to be able to control the transmission time of the test RF signal (hereinafter also referred to as “test radio wave”) by the RF transmission circuit 110 . Specifically, in the embodiment of the present invention, the RF transmission circuit 110 and the control unit 180 are connected so that the control unit 180 can control the transmission time of the test radio waves by the RF transmission circuit 110. It is

In the embodiment of the present invention, test radio waves and RF signals during operation (hereinafter, also referred to as "operation radio waves") are verbally distinguished. However, the test radio waves and the operational radio waves do not have to have different characteristics, and may have similar characteristics.

FIG. 4 is a block diagram showing a detailed configuration example of the monitoring unit 181. As shown in FIG. As shown in FIG. 4 , the monitoring unit 181 includes an acquisition unit 183 , an initial value identification unit 184 and a function control unit 185 .

The acquisition unit 183 acquires the output level (first output level) (hereinafter also referred to as “AD value 0”) at the first transmission wave slot (first time) among the transmission wave slots within the transmission time of the test radio wave. described.) is obtained from the AD converter 170 . In addition, the acquisition unit 183 obtains an output level (second output level) (hereinafter referred to as “AD value t”) at a transmission wave slot (second time) after the transmission time of the test radio wave has elapsed from the first transmission wave slot. ) is obtained from the AD converter 170 . The obtaining unit 183 stores the obtained AD value 0 and the AD value t in the storage unit 182 .

The initial value specifying unit 184 determines the output level (AD value 0) in the first transmission wave slot and the output level (AD value t ), the initial value of the amount of attenuation of the transmission signal by the DVATT 120 (hereinafter also referred to as “ATT value c”) is specified.

The function control section 185 sets the transmission time of the test radio waves and stops the ALC control operation by the monitoring section 181 . The function control unit 185 causes the RF transmission circuit 110 to start outputting the test radio waves in a state where the ALC control operation is stopped. Also, the function control unit 185 activates the ALC control operation by the monitoring unit 181 after the set transmission time has elapsed. The function control unit 185 causes the RF transmission circuit 110 to start outputting an RF signal for operation by the RF transmission circuit 110 (hereinafter also referred to as an “operation radio wave”) in a state where the ALC control operation is activated.

The functional configuration example of the communication device 10 according to the embodiment of the present invention has been described above.

(Output control according to comparative example)
Next, the output level by the output control according to the comparative example will be explained.

FIG. 5 is a diagram showing an example of output levels of burst transmission signals by output control according to a comparative example. Referring to FIG. 5, in the comparative example, the output level corresponding to the first transmission wave slot is increased. Due to the ALC control operation, the output level (for example, the output level corresponding to the third transmission wave slot) is stable after a certain period of time has passed since the first transmission wave slot.

(Output control according to the embodiment of the present invention)
FIG. 6 is a diagram showing temporal changes in the output level of test radio waves according to the embodiment of the present invention. Referring to FIG. 6, the output level corresponding to the first transmission wave slot takes the maximum value. The acquiring unit 183 acquires from the AD converter 170 the output level (AD value 0) in the first transmission wave slot among the transmission wave slots within the transmission time of the test radio wave. Further, the acquisition unit 183 acquires from the AD converter 170 the output level (AD value t) in the transmission wave slot after the transmission time of the test radio wave has elapsed from the first transmission wave slot.

The transmission time of the test radio wave may be any time during which the output level of the transmission signal is stable, such as 30 seconds. An example of the test radio wave transmission time will be described with reference to FIG.

The obtaining unit 183 stores the obtained AD value 0 and the AD value t in the storage unit 182 .

FIG. 7 is a graph showing temporal changes in the output level of a general DSRC radio device when the ALC control operation by the monitoring unit 181 is stopped. Referring to FIG. 7, in the state where the ALC control operation is stopped, the output level of the transmission signal is maximized immediately after the start of transmission (0 s). It is understood that the output level of the transmission signal is stable 30 seconds after the start of transmission even in a state where the ALC control operation is stopped. That is, the function control section 185 may set the transmission time of the test radio wave to 30 seconds.

FIG. 8 is a flow chart showing the operation of the output control method by the communication device 10 according to the embodiment of the present invention. As shown in FIG. 8, the function control unit 185 sets the transmission time (eg, 30 seconds) of the test radio wave (S11). In addition, the function control unit 185 sets the attenuation of the transmission signal by the DVATT 120 to the initial value of the attenuation during the test (hereinafter also referred to as "ATT value 0") (S12). The function control unit 185 stops the ALC control operation by the monitoring unit 181 (S13).

The function control unit 185 controls the RF transmission circuit 110 so as to output the test radio waves for the set transmission time (S14). The acquisition unit 183 acquires the output level (AD value 0) corresponding to the first transmission wave slot of the test radio wave from the AD converter 170 . Further, the acquisition unit 183 acquires the output level (AD value t) of the set test radio wave after the transmission time has elapsed from the first transmission wave slot from the AD converter 170 (S15).

The initial value identifying unit 184 determines the DVATT 120 based on the output level (AD value 0) corresponding to the first transmission wave slot and the output level (AD value t) after the set transmission time of the test radio wave has elapsed. Attenuation (ATT value 0t) of the transmission signal due to is calculated. More specifically, the initial value specifying unit 184 subtracts the output level (AD value t) after the set transmission time of the test radio wave has elapsed from the output level (AD value 0) corresponding to the first transmission wave slot. Then, the difference (AD value 0t) is calculated. Then, the initial value identification unit 184 calculates the attenuation amount (ATT value 0t) of the transmission signal by the DVATT 120 corresponding to the difference (AD value 0t) (S16).

Note that the correspondence relationship between the difference (AD value 0t) and the attenuation amount (ATT value 0t) may be stored in the storage unit 182 in advance. For example, the correspondence between the difference (AD value 0t) and the attenuation (ATT value 0t) may be such that the larger the difference (AD value 0t), the larger the attenuation (ATT value 0t).

The initial value specifying unit 184 calculates the attenuation (ATT value c) of the transmission signal by the DVATT 120 by adding the initial attenuation (ATT value 0) and the calculated attenuation (ATT value 0t) during the test. Calculate (S17). The initial value specifying unit 184 sets the calculated attenuation (ATT value c) as the initial value of the attenuation during operation (S18). The function control unit 185 activates the ALC control operation by the monitoring unit 181 based on the setting of the initial value of the attenuation amount during operation (S19). The function control unit 185 controls the RF transmission circuit 110 to start outputting operating radio waves (S20).

Here, the ALC control can mean comparing the output level input from the AD converter 170 and the specified output level stored in the storage unit 182 and controlling the DVATT 120 according to the comparison result.

For example, ALC control adjusts the attenuation (first attenuation) of the transmission signal (first transmission signal) corresponding to the first transmission wave slot based on the initial value of the attenuation during operation. may include controlling the DVATT 120 to do so. More specifically, the ALC control may include outputting an initial value of attenuation during operation to DVATT 120 as the attenuation of the transmission signal corresponding to the first transmission wave slot.

Further, the ALC control sets the attenuation amount (second attenuation amount) of the transmission signal (second transmission signal) corresponding to the second and subsequent transmission wave slots (hereinafter also referred to as "adjustment slot") to AD It may include adjusting according to the output level input from the converter 170 . Here, the output level input from the AD converter 170 corresponds to the output level of the transmission signal (third transmission signal) corresponding to the transmission wave slot (hereinafter also referred to as "reference slot") preceding the adjustment slot. Applicable.

Note that the correspondence between adjustment slots and reference slots is not limited. For example, the reference slot may be the transmission wave slot that precedes the adjustment slot by one, or may be the transmission wave slot that precedes the adjustment slot by two or more slots. Alternatively, the reference slot may include multiple transmit wave slots. For example, the attenuation of the transmission signal corresponding to the adjustment slot may be adjusted based on the average value (for example, moving average) of the output levels of the transmission signal corresponding to a plurality of transmission wave slots included in the reference slot.

Also, the frequency with which the attenuation of the transmission signal corresponding to the adjustment slot is adjusted is not limited. For example, the attenuation of the transmission signal corresponding to the adjustment slot may be adjusted at predetermined intervals. Alternatively, the attenuation of the transmission signal corresponding to the adjustment slot is the output level of the transmission signal corresponding to the reference slot, or the average value of the output levels of the transmission signals corresponding to a plurality of transmission wave slots included in the reference slot, Adjustments may be made when the threshold is exceeded.

The monitoring unit 181 controls the DVATT 120 to increase the attenuation of the transmission signal by the DVATT 120 when the output level input from the AD converter 170 is higher than the specified output level. On the other hand, when the output level input from the AD converter 170 is lower than the specified output level, the monitoring section 181 controls the DVATT 120 to reduce the attenuation of the transmission signal by the DVATT 120 . ALC control can be realized in this way.

An operation example of the output control method by the communication device 10 according to the embodiment of the present invention has been described above.

[Explanation of effect]
As described above, according to the embodiment of the present invention, the temperature sensor is unnecessary, so the cost for providing the temperature sensor can be reduced.

FIG. 9 is a diagram showing an example of output levels of operating radio waves by output control according to the embodiment of the present invention. According to the embodiment of the present invention, the initial value of the attenuation during operation is set based on the change in the AD value when the ALC control operation is stopped when the test radio wave is output. Since the output level immediately after the start of transmission of the operating radio wave is controlled based on the initial value of the attenuation amount during operation set in this way, the output level immediately after the start of transmission of the operating radio wave is shown in FIG. may greatly exceed the specified output level.

Further, in the technique described in Patent Document 1, as described above, the control value when the output level is stabilized at the predetermined output level is written in the memory in association with the transmission frequency and the temperature. That is, in the technique described in Patent Document 1, ALC control operation is performed in order to stabilize the output level, so it takes a considerable amount of time until the output level is stabilized. On the other hand, according to the embodiment of the present invention, since the ALC control operation is not required until the output level of the test radio wave stabilizes, the time required until the output level of the test radio wave stabilizes can be shortened.

[Explanation of modification]
Although the preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention belongs can conceive of various modifications or modifications within the scope of the technical idea described in the claims. It is understood that these also naturally belong to the technical scope of the present invention.

In the above description, the function control unit 185 sets the time (30 seconds) after the output level of the transmission signal is stabilized as the transmission time of the test radio wave. However, the function control section 185 may set the transmission time of the test radio wave to a time (for example, 15 seconds) before the output level stabilizes. At this time, the initial value specifying unit 184 determines the output level (AD value 0) in the first transmission wave slot and the output level (AD value T ), the initial value of the attenuation amount (ATT value c) during operation of the transmission signal by the DVATT 120 may be estimated. This makes it possible to further shorten the time.

More specifically, the initial value specifying unit 184 determines the output level (AD value 0) corresponding to the first transmission wave slot from the output level ( The AD value T) may be subtracted to calculate the difference (AD value 0T). Then, the initial value identification unit 184 may estimate the attenuation amount (ATT value 0t) of the transmission signal by the DVATT 120 corresponding to the difference (AD value 0T).

Note that the correspondence relationship between the difference (AD value 0T) and the attenuation amount (ATT value 0t) may be stored in the storage unit 182 in advance. For example, the correspondence between the difference (AD value 0T) and the attenuation (ATT value 0t) may be such that the larger the difference (AD value 0T), the larger the attenuation (ATT value 0t).

10 communication device 110 RF transmission circuit 120 DVATT
130 amplifier 140 detection circuit 160 output unit 170 AD converter 180 control unit 181 monitoring unit 182 storage unit 183 acquisition unit 184 initial value identification unit 185 function control unit

Claims (8)

an acquisition unit that acquires a first output level of a transmission signal at a first time and a second output level of a transmission signal at a second time after the first time;
an initial value identifying unit that identifies an initial value of attenuation of a transmission signal based on the first output level and the second output level;
A first attenuation amount of a first transmission signal is adjusted based on the initial value, and a second attenuation amount of a second transmission signal transmitted after the first transmission signal is adjusted to the second attenuation amount. a function control unit that activates an automatic control operation that adjusts according to the output level of a third transmission signal that is transmitted before the transmission signal;
An information processing device. The function control unit stops the automatic control operation,
The acquisition unit acquires the first output level and the second output level in a state where the automatic control operation is stopped,
The function control unit activates the automatic control operation based on the identification of the initial value.
The information processing device according to claim 1 . The automatic control operation includes controlling to increase the attenuation amount when the output level of the third transmission signal is greater than a specified output level.
The information processing apparatus according to claim 1 or 2. The automatic control operation includes controlling to decrease the attenuation amount when the output level of the third transmission signal is lower than a specified output level.
The information processing apparatus according to claim 1 or 2. The initial value identifying unit calculates a difference by subtracting the second output level from the first output level, and identifies an attenuation amount corresponding to the difference as the initial value.
The information processing apparatus according to any one of claims 1 to 4. The greater the difference, the greater the attenuation corresponding to the difference,
The information processing device according to claim 5 . obtaining a first output level of a transmission signal at a first time and a second output level of a transmission signal at a second time after the first time;
identifying an initial value of attenuation of a transmission signal based on the first output level and the second output level;
A first attenuation amount of a first transmission signal is adjusted based on the initial value, and a second attenuation amount of a second transmission signal transmitted after the first transmission signal is adjusted to the second attenuation amount. activating an automatic control operation that adjusts according to the output level of a third transmission signal transmitted prior to the transmission signal;
A method of processing information, comprising: the computer,
an acquisition unit that acquires a first output level of a transmission signal at a first time and a second output level of a transmission signal at a second time after the first time;
an initial value identifying unit that identifies an initial value of attenuation of a transmission signal based on the first output level and the second output level;
A first attenuation amount of a first transmission signal is adjusted based on the initial value, and a second attenuation amount of a second transmission signal transmitted after the first transmission signal is adjusted to the second attenuation amount. a function control unit that activates an automatic control operation that adjusts according to the output level of a third transmission signal that is transmitted before the transmission signal;
A program that functions as an information processing device comprising

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