JP2012009960A - Delay measuring system and delay measuring method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a delay measuring system and a delay measuring method in which a delay time in one direction can be accurately measured even in the environment where communication with an NTP server or a satellite can not be performed.SOLUTION: In a delay measuring system, a transmitting-side delay measuring apparatus 10 and a receiving-side delay measuring apparatus 20 include a transmitting-side clock section 12 and a receiving-side clock section 22 for acquiring a common time Tfrom a common clock source 30 for time synchronism at the common time T. Even in the environment where the common time Tcan not be acquired, the transmitting-side delay measuring apparatus 10 and the receiving-side delay measuring apparatus 20 can maintain time synchronism with each other.

Description

  The present invention relates to a delay measurement system and a delay measurement method for measuring a delay time of a signal transmitted between two points.

  A delay measurement system for measuring a delay time of a signal transmitted between two points has been proposed (see, for example, Patent Document 1). The delay measurement system of Patent Document 1 measures the delay time of a signal under measurement from one device to the other device by two devices transmitting and receiving a signal under delay measurement. In order to synchronize time with each other, the two devices communicate with a common clock source, and transmit and receive a signal under measurement while acquiring the common time from the common clock source. As the common clock source, an NTP (Network Time Protocol) server or a satellite of a satellite positioning system is used.

JP 2008-118270 A

  If an attempt is made to measure the delay time of a signal transmitted between two points, there may be an environment where communication with an NTP server or a satellite cannot be performed. For example, in a station where equipment is brought in when a network is opened or maintained. Since the network is not connected in the office building, the common time cannot be acquired from the NTP server. In addition, since the radio wave from the satellite of the satellite positioning system does not reach inside the station building, it is not possible to acquire the common time from the satellite. For this reason, the delay measurement system of Patent Document 1 has a problem in that time synchronization between two devices cannot be performed in an environment where communication with an NTP server or a satellite cannot be performed.

  On the other hand, a method of measuring the round trip time of the signal under measurement using one apparatus is also conceivable. However, this method has a problem that the delay time in one direction cannot be measured separately.

  Therefore, an object of the present invention is to provide a delay measurement system and a delay measurement method capable of accurately measuring a delay time in one direction even in an environment where communication with an NTP server or a satellite cannot be performed.

  In order to achieve the above object, the delay measurement system of the present invention includes a transmission side time acquisition unit (11) for acquiring a common time from a common clock source, a time stamped by an independent oscillator, and a periodic or external instruction. The transmission side time is synchronized with the common time acquired by the transmission side time acquisition unit, the transmission side clock unit (12) that outputs the transmission side time is acquired, and the transmission side time is acquired from the transmission side clock unit. A transmission-side delay measurement device (10) including a time information transmission unit (13) for transmitting the signal under measurement on the transmission-side time and a reception-side time acquisition unit for acquiring a common time from the common clock source ( 21) a receiving side clock unit that clocks the time with an independent oscillator, synchronizes with the common time acquired by the receiving side time acquiring unit periodically or according to an external instruction, and outputs the receiving side time ( 2) A time information receiving unit (23) that receives a signal under measurement transmitted from the time information transmitting unit and outputs a transmission side time carried on the signal under measurement, and a reception side time from the reception side clock unit From the time information transmission unit to the time information reception unit using the reception side time to be detected and the transmission side time from the time information reception unit. A delay measuring device (20) on the receiving side that includes a delay calculating unit (24) that calculates a delay time of the signal under measurement.

  Since the transmission side delay measurement device (10) includes a time information transmission unit (13) and the reception side delay measurement device (20) includes a time information reception unit (23) and a delay calculation unit (24), the time information transmission unit The delay time of the signal under measurement from (13) to the time information receiver (23) can be calculated. Here, the transmission side delay measurement device (10) includes a transmission side time acquisition unit (11) and a transmission side clock unit (12), and the reception side delay measurement device (20) includes a reception side time acquisition unit (21) and reception. Since the side clock unit (22) is provided, the time is synchronized by a common clock source, and then the time is recorded by independent oscillators, so that even in an environment where communication with the NTP server or satellite cannot be performed, Time synchronization of the receiving side delay measuring device (20) can be maintained. Thereby, even in an environment where communication with an NTP server or a satellite cannot be performed, the delay time in one direction depends on the accuracy of the oscillator mounted on the transmission side delay measurement device (10) and the reception side delay measurement device (20). Can be measured with high accuracy. Therefore, the delay measurement system of the present invention can accurately measure the delay time in one direction even in an environment where communication with an NTP server or satellite cannot be performed.

In the delay measurement system of the present invention, the transmission-side delay measurement device acquires a common time from the transmission-side time acquisition unit, acquires a transmission-side time from the transmission-side clock unit, and sets the common time and the transmission-side time. A transmission side delay calculation unit (15) for calculating a transmission side delay between the transmission side and a transmission side delay obtained by the transmission side delay calculation unit is used to determine a transmission side time output from the transmission side clock unit. A transmission-side time correction unit (16) for correcting, the reception-side delay measurement device acquires a common time from the reception-side time acquisition unit, and acquires a reception-side time from the reception-side clock unit. A receiving side delay calculating unit (25) for calculating a receiving side delay between a time and a receiving side time, and the receiving side clock unit using the receiving side delay acquired by the receiving side delay calculating unit; Receiving side to correct the receiving side time output by A time correction unit (26), wherein the transmission side time acquisition unit and the reception side time acquisition unit acquire a common time from the common clock source a plurality of times, and the time information transmission unit includes the transmission side The corrected transmission side time is acquired from the time correction unit, and the measured signal is transmitted with the transmission side time at the time of transmission of the measured signal, and the delay calculation unit is corrected from the reception side time correction unit. Is received from the time information transmission unit using the reception side time to be detected and the transmission side time from the time information reception unit. A delay time of the signal under measurement up to the information receiving unit may be calculated. Here, the transmission-side delay means how much the transmission-side time is delayed or advanced with respect to the common time. Further, the reception side delay refers to how much the reception side time is delayed or advanced with respect to the common time.
Since the transmission-side delay measuring device (10) includes the transmission-side delay calculation unit (15) and the transmission-side time correction unit (16), the time chopped by an independent oscillator is corrected by the transmission-side delay, and after correction Can be placed on the signal under measurement. Since the reception-side delay measurement device (20) includes the reception-side delay calculation unit (25) and the reception-side time correction unit (26), the time chopped by the independent oscillator is corrected by the reception-side delay, and after correction The receiving side time can be used.

In the delay measurement system of the present invention, the transmission-side delay measurement device acquires a common time from the transmission-side time acquisition unit, acquires a transmission-side time from the transmission-side clock unit, and sets the common time and the transmission-side time. A transmission-side delay calculation unit (15) that calculates a transmission-side delay between the reception-side delay measurement apparatus and the reception-side delay acquisition unit that acquires a common time from the reception-side time acquisition unit and from the reception-side clock unit A receiving-side delay calculating unit (25) that acquires a time and calculates a receiving-side delay between the common time and the receiving-side time, and the transmitting-side time acquiring unit and the receiving-side time acquiring unit include: A common time from a common clock source is acquired a plurality of times, and the time information transmission unit acquires a transmission side delay from the transmission side delay calculation unit, and the signal under measurement further loaded with the transmission side delay The time information receiver The transmission side delay carried on the signal under measurement is further output, the delay calculation unit further acquires the transmission side delay from the time information reception unit to correct the transmission side time, and the reception side The reception side delay is acquired from the delay calculation unit, the reception side time is corrected, and the corrected time from the time information transmission unit to the time information reception unit is corrected using the corrected transmission side time and reception side time. The delay time of the measurement signal may be calculated.
Since the transmission-side delay measuring device (10) includes the transmission-side delay calculation unit (15), the transmission-side delay that can correct the time ticked by an independent oscillator can be placed on the signal under measurement. Since the reception-side delay measurement device (20) includes the reception-side delay calculation unit (25), it is possible to acquire the reception-side delay that can correct the time ticked by an independent oscillator. Therefore, the delay calculation unit (24) can correct the transmission side time using the transmission side delay, and can correct the reception side time using the reception side delay.

  In order to achieve the above object, in the delay measurement method of the present invention, the transmission side delay measurement device (10) and the reception side delay measurement device (20) acquire a common time from a common clock source, and the time is measured by an independent oscillator. A time synchronization procedure (S101) for synchronizing the transmission side time in the transmission side delay measurement device and the reception side time in the reception side delay measurement device periodically or in accordance with an instruction from the outside, A signal-under-measurement procedure (S102) for transmitting the signal-under-measurement with the transmission-side time at the time of transmission from the transmission-side delay measurement device to the reception-side delay measurement device; and a reception side when receiving the signal under measurement Delay calculation for calculating a delay time of the signal under measurement from the transmission side delay measurement device to the reception side delay measurement device using the time and the transmission side time carried on the signal under measurement A forward (S103), in sequence.

  Since the measured signal transmission procedure (S102) and the delay calculation procedure (S103) are sequentially provided, the delay time of the measured signal from the transmission side delay measurement device (10) to the reception side delay measurement device (20) is calculated. can do. Here, since there is a time synchronization procedure (S101) before the signal under test transmission procedure (S102), after synchronizing the time with a common clock source, each time is recorded with an independent oscillator to communicate with the NTP server and satellite. Even in an environment where this is not possible, time synchronization between the transmission side delay measurement device (10) and the reception side delay measurement device (20) can be maintained. Thereby, even in an environment where communication with an NTP server or a satellite cannot be performed, the delay time in one direction depends on the accuracy of the oscillator mounted on the transmission side delay measurement device (10) and the reception side delay measurement device (20). Can be measured with high accuracy. Therefore, the delay measurement method of the present invention can accurately measure the delay time in one direction even in an environment where communication with an NTP server or satellite cannot be performed.

In the delay measurement method of the present invention, the transmission side delay measurement device and the reception side delay measurement device acquire the common time from the common clock source after a predetermined time from the time synchronization procedure, and the transmission side delay measurement device acquires The transmission side time is corrected using the transmission side delay between the common time and the transmission side time, and the reception side delay between the common time and the reception side time acquired by the reception side delay measurement device is used. A time correction procedure (S104) for correcting the reception side time is further provided between the time synchronization procedure and the measured signal transmission procedure, and the transmission side time corrected by the time correction procedure in the measured signal transmission procedure. Is transmitted from the transmission-side delay measurement device to the reception-side delay measurement device, and the delay calculation procedure uses the reception-side time corrected by the time correction procedure. From said signal side delay measurement device to the receiving delay measurement device may calculate the delay time of the signal to be measured.
Since there is a time correction procedure (S104) before the measured signal transmission procedure (S102), the time chopped by the independent oscillator is corrected by the transmission side delay and the reception side delay, and the corrected transmission side time is obtained. It is possible to calculate the delay time of the signal under measurement by using the corrected reception side time on the signal under measurement.

In the delay measurement method of the present invention, the transmission side delay measurement device and the reception side delay measurement device acquire the common time from the common clock source after a predetermined time from the time synchronization procedure, and the transmission side delay measurement device acquires The delay calculation procedure for calculating the transmission side delay between the common time and the transmission side time and calculating the reception side delay between the common time and the reception time acquired by the reception side delay measuring device (S105) ) Between the time synchronization procedure and the measured signal transmission procedure, and in the measured signal transmission procedure, the transmission side delay calculated in the delay calculation procedure is further placed on the measured signal. The signal under measurement is transmitted from the transmission side delay measurement device to the reception side delay measurement device, and in the delay calculation procedure, the transmission side delay is transmitted using the transmission side delay transmitted in the signal under measurement transmission procedure. The reception side time is corrected using the reception side delay calculated in the delay calculation procedure, and the corrected transmission side time and reception side time are used to correct the reception side time. The delay time of the signal under measurement up to the reception-side delay measurement device may be calculated.
Since the delay calculation procedure (S105) is provided before the signal under measurement transmission procedure (S102), it is possible to acquire the transmission side delay and the reception side delay that can correct the time ticked by an independent oscillator. For this reason, in the delay calculation procedure, the transmission side time can be corrected using the transmission side delay, and the reception side time can be corrected using the reception side delay.

  According to the present invention, it is possible to provide a delay measurement system and a delay measurement method capable of accurately measuring a one-way delay time even in an environment where communication with an NTP server or a satellite cannot be performed.

1 shows an example of a delay measurement system according to a first embodiment. 2 shows an example of a delay measurement method according to the first embodiment. Time is a specific example of the synchronization, (a) shows common time _{T O,} indicates (b) transmitting side time _{T S,} indicates the reception-side time _{T R} (c). An example of the delay measurement system which concerns on Embodiment 2 is shown. An example of the delay measurement method according to the second embodiment will be described. It is a correction of the transmitting side time _{T S} and the receiving time _{T R,} indicating the (a) shows a common time _{T O,} (b) shows the transmission-side time _{T S,} (c) the receiving side time _{T R} . An example of the delay measurement system which concerns on Embodiment 3 is shown. An example of the delay measuring method which concerns on Embodiment 3 is shown.

  Embodiments of the present invention will be described with reference to the accompanying drawings. The embodiments described below are examples of the present invention, and the present invention is not limited to the following embodiments. In the present specification and drawings, the same reference numerals denote the same components.

(Embodiment 1)
FIG. 1 shows an example of a delay measurement system according to the first embodiment. The delay measurement system according to the first embodiment includes a transmission side delay measurement device 10 and a reception side delay measurement device 20. The transmission side delay measuring apparatus 10 includes a transmission side time acquisition unit 11, a transmission side clock unit 12, a time information transmission unit 13, an oscillator 17, and an antenna 18. The reception side delay measurement device 20 includes a reception side time acquisition unit 21, a reception side clock unit 22, a time information reception unit 23, a delay calculation unit 24, and an oscillator 27.

Transmitting-side clock 12, increments the time according to the timing of the independent oscillator 17, and outputs the transmission-side time T _S. Receiving clock 22, increments the time according to the timing of the independent oscillator 27, and outputs the reception-side time T _R.

  FIG. 2 shows an example of the delay measurement method according to the first embodiment. The delay measurement method according to the first embodiment includes a time synchronization procedure S101, a measured signal transmission procedure S102, and a delay calculation procedure S103 in order. The details of the delay measurement method according to the first embodiment will be described below with reference to FIG.

In the time synchronization procedure S101, time synchronization of the transmission side delay measurement device 10 and the reception side delay measurement device 20 is performed. For example, common time T _O The acquired sender time T _S and the receiving delay measurement device on the transmission side delay measurement device 10 from the transmission side delay measurement device 10 and the receiving delay measurement device 20 is a common clock source 30 20 the receiving side time T _R of the inner is time synchronization.

For example, the antenna 18 receives radio waves from the common clock source 30. Transmitting-side time acquisition unit 11 acquires the common time T _O from a common clock source 30. Transmitting-side clock unit 12 time synchronized to a common time T _O to obtain the transmission-side time acquisition unit 11. On the other hand, the antenna 28 receives radio waves from the common clock source 30. Recipient time acquisition unit 21 acquires the common time T _O from a common clock source 30. Receiving clock unit 22 time synchronized to a common time T _O to obtain the reception side time acquisition unit 21. Thus, it is possible to the receiving side time T _R to the output of the transmitting side time T _S and the receiver clock unit 22 for outputting the transmission-side clock 12 time synchronized.

Figure 3 is a specific example of time synchronization, (a) shows common time _{T O,} it indicates (b) transmitting side time _{T S,} indicates the reception-side time _{T R} (c). The transmission side time acquisition unit 11 and the reception side time acquisition unit 21 acquire, for example, the common time T 0 “ _10:00:00 ”. The transmission side clock unit 12 sets the next time to be cut by the timing from the oscillator 17 to “10:00:01” and outputs it. After this, the transmission side clock unit 12, in accordance with the timing from the oscillator 17, "10 o'clock 00 minutes 02 seconds", engrave the sender time _{T S} and ... "10 o'clock 00 minutes 03 seconds". The receiving-side clock unit 22 outputs the next time that is ticked by the timing from the oscillator 27 as “10:00:01”. After this, the receiving clock unit 22, in accordance with the timing from the oscillator 27, "10 o'clock 00 minutes 02 seconds", engrave the sender time _{T S} and ... "10 o'clock 00 minutes 03 seconds".

Here, the time synchronization procedure S101 is executed periodically or according to an external instruction. Regularly, for example, a fixed time intervals after the launch of certain common time T _O or sender delay measurement device 10 and the receiving delay measurement device 20. As an instruction from the outside, for example, a time synchronization instruction is input to the transmission-side clock unit 12 and the reception-side clock unit 22 using input means provided in the transmission-side delay measurement device 10 and the reception-side delay measurement device 20. In the time synchronization procedure S101, since it is necessary to receive radio waves from the common clock source 30, it is executed in an environment where communication with the satellite before entering the station building is possible.

After entering the station, the measured signal transmission procedure S102 is executed. In the measured signal transmission procedure S102, the measured signal S is transmitted from the transmission side delay measurement apparatus 10 to the reception side delay measurement apparatus 20 via the communication network 100. At this time, the signal under measurement _S is loaded with the transmission side time TS when the signal under measurement S is transmitted. The signal under measurement S is, for example, a packet in which the IP address of the receiving side delay measuring device 20 is placed on the destination address and the IP address of the sending side delay measuring device 10 is placed on the source address.

For example, the time information transmission unit 13 acquires the transmission side time T _S “ _10:00:03 ” from the transmission side clock unit 12. Then, the time information transmission unit 13 transmits the signal under measurement S with the transmission side time T _S “ _10:00:03 ” when the signal under measurement S is transmitted. The time information receiving unit 23 receives the signal under measurement S transmitted from the time information transmission unit 13 and outputs the transmission side time T _S “ _10:00:03 ” carried on the signal under measurement S.

In the delay calculation procedure S103, the reception side delay measuring device from a sending delay measurement device 10 by using the transmission-side time T _S, which is placed on the receiving side time T _R and the measured signal S at the time of reception of the measured signal S 20 Until the delay time of the signal under measurement S is calculated.

For example, the delay calculating unit 24, the receiving clock unit receiving side time _{T R} "10 hour 00 minutes and 30 seconds" to 22 are input, the receiving side time _{T R} "10 00 30 at the time of reception of the measured signal S "Second" is detected. Further, the delay calculation unit 24 transmits time information using the detected reception side time T _R “10:00:30” and the transmission side time T _S “ _10:00:03 ” from the time information reception unit 23. The delay time “27 seconds” of the signal under measurement S from the unit 13 to the time information receiving unit 23 is calculated.

Increments the time by an oscillator 17 the sending clock unit 12 are independent, because keeps time by an oscillator 27 receiving clock 22 is independently synchronize the oscillator 17 and the oscillator of the transmitting side time T _S and the receiving time T _R 27 Can be maintained with an accuracy depending on the accuracy of Since the accuracy of the oscillator 17 and the oscillator 27 is very high compared to the time, the delay measurement system and the delay measurement method according to the present embodiment transmit and receive the signal under measurement while maintaining the time synchronization even in the office building. Can do.

The transmission-side time acquisition unit 11 and the receiving time acquiring unit 21 has been acquired common time T _O from satellites of a satellite positioning system using the antenna 18 and the antenna 28 is not limited to this. For example, the sending time acquiring unit 11 and the receiving time acquiring unit 21 has a communication means with the NTP (Network Time Protocol) server may acquire the common time _{T O} from NTP.

Sender delay measurement device 10, the history storage unit for the transmission-side time acquiring unit 11 stores the date and time acquired common time T _O (not shown), a predetermined time from the latest date and time stored in the history storage unit If it passes, the display part (not shown) which displays that the said fixed time passed may be provided. The certain time can be arbitrarily set, for example, set to a time at which the time synchronization between the transmission side clock unit 12 and the reception side clock unit 22 starts to be lost. The display unit displays, for example, “There is a possibility that the time is not synchronized. Start the time synchronization.” In this case, the reception-side delay measurement device 20 is also provided with a history storage unit (not shown) and a display unit (not shown). As described above, since the transmission-side delay measurement device 10 and the reception-side delay measurement device 20 include the history storage unit (not shown) and the display unit, reliability of time synchronization of the transmission-side clock unit 12 and the reception-side clock unit 22 is achieved. Can be maintained. Thereby, a more accurate delay time can be measured.

Further, when the transmission-side time acquiring unit 11 can acquire the common time T _O from a common clock source 30 in the central office, the transmission-side time acquisition unit 11 is also in signal transmission procedure S102 to be measured to obtain a common time T _O Also good. In this case, it is preferable to provide a time synchronization selection switch for outputting an instruction to continue the acquisition of common time T _O to the sending time acquisition unit 11.

If the receiving time acquiring unit 21 can acquire the common time T _O from a common clock source 30 in the central office receiving and transmitting-side time acquisition unit 21 in the delay calculation procedure S103 may obtain a common time T _O. In this case, it is preferable to provide a time synchronization selection switch for outputting an instruction to continue the acquisition of common time T _O to the receiving and transmitting side time acquisition unit 21.

(Embodiment 2)
FIG. 4 shows an example of a delay measurement system according to this embodiment. Delay measurement system of this embodiment has a configuration for correcting the indolent against common time T _O of the sending time T _S and the receiving time T _R. For example, the transmission-side delay measurement device 10 of the present embodiment further includes a transmission-side delay calculation unit 15 and a transmission-side time correction unit 16 in addition to the transmission-side delay measurement device 10 of the first embodiment. The reception-side delay measurement device 20 of the present embodiment further includes a reception-side delay calculation unit 25 and a reception-side time correction unit 26 in addition to the reception-side delay measurement device 20 of the first embodiment.

  FIG. 5 shows an example of a delay measurement method according to the present embodiment. The delay measurement method of this embodiment further includes a time correction procedure S104 between the time synchronization procedure S101 and the signal under measurement transmission procedure S102 described in the first embodiment.

At time correction procedure S104, the time to acquire a common time T _O at the transmission side delay measurement device 10 and the receiving delay measurement device 20 from a common clock source 30 after a predetermined time from the synchronization procedure S101. The fixed time is after an arbitrary time, and is determined according to the accuracy of the transmission side clock unit 12 and the reception side clock unit 22. The transmission side time T _S is corrected using the transmission side delay T _SD between the common time T _O acquired by the transmission side delay measurement device 10 and the transmission side time T _S , and the reception side delay measurement device 20 acquires it. correcting the receiving-side time T _R with the recipient indolent T _RD between the common time T _O and the receiving time T _R.

For example, the sending time acquiring unit 11 acquires a plurality of times a common time T _O from a common clock source 30. Timing the sending time acquiring unit 11 acquires the common time T _O is arbitrary, for example, every fixed time. Sender indolent calculation unit 15 obtains the transmission-side time T _S from the transmitter-side clock unit 12 acquires the common time T _O from the transmitting time acquisition unit 11, a common time T _O and sender time T _S It calculates the transmission side indolent T _SD between. Transmitting-side time correcting unit 16 uses the sender indolent T _SD of acquiring the transmitting side indolent calculator 15, corrects the sender time T _S for outputting the transmission-side clock unit 12, the transmission side of the corrected and it outputs the time _{T SC.}

On the other hand, the receiving-side time acquisition unit 21 acquires a plurality of times a common time T _O from a common clock source 30. Timing the receiving time acquiring unit 21 acquires the common time T _O is arbitrary, for example, every fixed time. Recipient indolent calculator 25 acquires the receiving side time T _R from the receiving clock unit 22 acquires the common time T _O from the receiving time acquiring unit 21, a common time T _O and the receiving side time T _R The receiving side delay T _RD is calculated. Receiving side time correcting unit 26 uses the recipient indolent T _RD for obtaining the reception side indolent calculator 25, corrects the reception side the time T _R to the output of the receiving clock unit 22, the receiving side after the correction Output the time _TRC . For even recipient indolent T _RC and the receiving time T _RC corrected can be calculated similarly to the transmitting side indolent T _SD.

Figure 6 is a correction of the transmitting side time _{T S} and the receiving time _{T R,} (a) shows a common time _{T O,} (b) shows the transmission-side time _{T S,} (c) the receiving side time shows the T _R. Common time T _O obtained at the time synchronization procedure S101 is "10 hour 00 minute 00 second", and after a certain time is 3 seconds. In this case, the time synchronization sender indolent calculator 15 and the receiving side indolent calculating unit 25 acquires the "10:00 03 seconds" as a common time T _O.

Sender indolent calculating unit 15, the transmitting side clock section 12, acquires "00 minutes 05 seconds at 10" sender time T _S at acquisition common time T _O. In this case, the transmission side indolent calculating unit 15, a transmitting-side indolent T _SD is calculated as "2 seconds advances per 3 seconds". Then, the transmission side time correcting unit 16, the sending time _T if _S is "10 hour 00 minutes 06 seconds", the sending time _{T S} "10 time synchronization from the time" 10 o'clock 00 minutes 03 seconds, "went Time 3 seconds until “00:06” is calculated, and 3 seconds × (3/5) is calculated to calculate the corrected transmission side time _TSC as “10:00:04”.

The reception side delay calculation unit 25 acquires, from the transmission side clock unit 12, the reception side time T _R “ _10:00:02 ” when the common time _TO is acquired. In this case, the receiving-side indolent calculation unit 25, a reception-side indolent T _RD is calculated as "3 seconds 1 second delay per". Then, the receiving side time correcting unit 26, the receiving side time _T if _R is "10 hours, 00 minutes and 30 seconds", the receiving time _{T R} "10 from the time" 10 o'clock 00 minutes 03 seconds, "which was performed time synchronization 27 seconds × (3/2) is calculated by calculating time 27 seconds until “hour 00 minute 30 seconds”, and the corrected reception side time TRC is calculated as “ _10:00:40 ”.

In signal transmission procedure S102 to be measured, transmits the measured signal S carrying the transmitting side time T _SC after correction corrected by the time correction procedure S104 from the transmitting side delay measurement device 10 to the receiving delay measurement device 20. For example, if the transmission side time TS at the time of transmission of the signal under measurement _S is “10:00:06”, the time information transmission unit 13 corrects the transmission side time T _SC after the transmission side time correction unit 16 corrects. “10:00:04” is acquired, and the signal under measurement S is transmitted with the transmission side time T _SC “ _10:00:04 ” when the signal under measurement S is transmitted.

In the delay calculation procedure S103, it calculates the delay time of the measured signal S to the reception side delay measurement device 20 from the transmission side delay measurement device 10 with a receiving-side time T _RC corrected by the time correction procedure S104. For example, if the receiving side time T _R at the time of reception of the measured signal S is "10 hour 00 minute 30 seconds", the delay calculating unit 24, the receiving-side time T _RC corrected from the receiving time correcting unit 26 " “10:00:40” is input, and the receiving side time T _RC “ _10:00:40 ” when the signal under measurement S is received is detected. Then, the delay calculation unit 24 uses the detected reception side time T _RC “10:00:40” and the transmission side time T _SC “ _10:00:04 ” from the time information reception unit 23 to detect the time information. The delay time “36 seconds” of the signal under measurement S from the transmitter 13 to the time information receiver 23 is calculated.

Delay measurement system and a delay measuring method according to the present embodiment, the time correction procedure for having a S104, the oscillator 17 and a common time T _O generated due to the deviation of the timing of the oscillator 27 transmitting side time T _S and receiver deviation between the time T _R can be corrected. This makes it possible to improve the accuracy of maintaining the time synchronization of the transmitting side time T _S and the receiving time T _R. In the time correction procedure S104, but the acquisition of the common time T _O was performed only once, it may be twice or more.

(Embodiment 3)
FIG. 7 shows an example of a delay measurement system according to this embodiment. Delay measurement system of this embodiment has a configuration for correcting the indolent against common time T _O of the sending time T _S and the receiving time T _R. For example, the transmission-side delay measurement device 10 of the present embodiment further includes a transmission-side delay calculation unit 15 in the transmission-side delay measurement device 10 of the first embodiment. The reception-side delay measurement device 20 according to the present embodiment further includes a reception-side delay calculation unit 25 in addition to the reception-side delay measurement device 20 according to the first embodiment.

  FIG. 8 shows an example of a delay measurement method according to this embodiment. The delay measurement method of this embodiment further includes a delay calculation procedure S105 between the time synchronization procedure S101 and the signal under measurement transmission procedure S102 described in the first embodiment.

In indolent calculation procedure S105, the time to acquire a common time T _O at the transmission side delay measurement device 10 and the receiving delay measurement device 20 from a common clock source 30 after a predetermined time from the synchronization procedure S101. The fixed time is after an arbitrary time, and is determined according to the accuracy of the transmission side clock unit 12 and the reception side clock unit 22. Calculates a transmission side indolent T _SD between the common time T _O the sending time T _S acquired the transmission side delay measurement device 10, the common time T _O and the receiving time acquired in the reception side delay measuring device 20 calculating the recipient indolent _{T RD} between T _R.

For example, the sending time acquiring unit 11 acquires a plurality of times a common time T _O from a common clock source 30. Timing the sending time acquiring unit 11 acquires the common time T _O is arbitrary, for example, every fixed time. Sender indolent calculation unit 15 obtains the transmission-side time T _S from the transmitter-side clock unit 12 acquires the common time T _O from the transmitting time acquisition unit 11, a common time T _O and sender time T _S It calculates the transmission side indolent T _SD between. The specific calculation example of the transmission side indolent T _SD is as described in Embodiment 2.

On the other hand, the receiving-side time acquisition unit 21 acquires a plurality of times a common time T _O from a common clock source 30. Timing the receiving time acquiring unit 21 acquires the common time T _O is arbitrary, for example, every fixed time. Recipient indolent calculator 25 acquires the receiving side time T _R from the receiving clock unit 22 acquires the common time T _O from the receiving time acquiring unit 21, a common time T _O and the receiving side time T _R The receiving side delay T _RD is calculated. The specific example of calculation of the receiving side indolent T _RD is as described in Embodiment 2.

In the measured signal transmission procedure S102, further placed transmits to the receiving delay measurement device 20 to be measured signal S from the transmitter delay measurement device 10 on the transmitting side indolent T _SD of the measured signal S. For example, the time information transmission unit 13 acquires the transmission side time T _S from the transmission side clock unit 12, acquires the transmission side delay T _SD from the transmission side delay calculation unit 15, and transmits the transmission side time T _S and the transmission side time T _S. transmitting the measured signal S carrying the side indolent T _SD.

In the delay calculation procedure S103, it corrects the reception side time _{T R} with the recipient indolent _{T RD} calculated in indolent calculation procedure S105, using the sender indolent _{T SD} transmitted in signal transmission procedure S102 to be measured It corrects the sender time T _S, calculates the delay time of the measured signal S from the transmitter delay measurement device 10 to the reception side delay measurement device 20.

For example, the time information receiving unit 23 outputs the transmission side time T _S “10:00:06 seconds” and the transmission side delay T _SD “2 seconds advance per 3 seconds” carried on the signal under measurement S. . The delay calculation unit 24 acquires the transmission side time T _S “10:00:06 second” and the transmission side delay T _SD “2 seconds advance per 3 seconds” from the time information reception unit 23, and receives the reception side clock unit 22. The reception side time T _R “10:00:30” is acquired from the reception side, and the reception side delay calculation unit 25 acquires the reception side delay T _RD “a delay of 1 second per 3 seconds”.

Then, the delay calculating unit 24 corrects the transmission side time _{T S} using the transmission side indolent _{T SD.} For example, a sender indolent T _SD is "2 seconds per 3 seconds advances" If the transmission-side time T _S is "10:00 06 seconds", as described in the second embodiment, the corrected the transmission side time _{T SC} of calculating the "10 o'clock 00 minutes 04 seconds".

The delay calculating unit 24 corrects the reception side time _{T R} with the recipient indolent _{T RD.} For example, the receiving side indolent T _RD is "3 1 second per second delay", if the receiving side time T _R is "10 hour 00 minutes 30 seconds", as described in the second embodiment, the corrected _Is calculated as “10:00:40”.

Then, the delay calculation unit 24 calculates the delay time of the signal under measurement S from the time information transmission unit 13 to the time information reception unit 23 using the corrected transmission side time _TSC and reception side time _TRC . For example, the corrected transmission side time T _SC “10:00:04” is subtracted from the corrected reception side time T _RC “ _10:00:40 ”. Accordingly, the delay time of the signal under measurement S from the transmission side delay measurement device 10 to the reception side delay measurement device 20 can be calculated as “36 seconds”.

Delay measurement system and a delay measuring method according to the present embodiment has the indolent calculation procedure S105, common generated due to the shift of the timing of oscillator 17 and the oscillator 27 time T _O the sending time T _S and receiver it is possible to correct the deviation of the side time T _R. This makes it possible to improve the accuracy of maintaining the time synchronization of the transmitting side time T _S and the receiving time T _R. In indolent calculation procedure S105, but the acquisition of the common time T _O was performed only once, may be twice or more.

  The present invention can be applied to the information communication industry.

10: Transmission side delay measuring device 11: Transmission side time acquisition unit 12: Transmission side clock unit 13: Time information transmission unit 15: Transmission side delay calculation unit 16: Transmission side time correction unit 17: Oscillator 18: Antenna 20: Reception Side delay measurement device 21: reception side time acquisition unit 22: reception side clock unit 23: time information reception unit 24: delay calculation unit 25: reception side delay calculation unit 26: reception side time correction unit 27: oscillator 28: antenna 30 : Common clock source 100: Communication network

Claims (6)

A transmission side time acquisition unit (11) for acquiring a common time from a common clock source, clocking the time with an independent oscillator, and synchronizing the time with the common time acquired by the transmission side time acquisition unit periodically or by an external instruction The transmission side clock unit (12) for outputting the transmission side time and the transmission side time from the transmission side clock unit, and the time information for transmitting the signal under measurement with the transmission side time when transmitting the signal under measurement A transmission-side delay measurement device (10) including a transmission unit (13);
Receiving side time acquisition unit (21) for acquiring a common time from the common clock source, clocking the time with an independent oscillator, and synchronizing the time with the common time acquired by the receiving side time acquisition unit periodically or by an external instruction A receiving side clock unit (22) for outputting the receiving side time, and receiving time information for receiving the measured signal transmitted from the time information transmitting unit and outputting the transmitting side time carried on the measured signal. Unit (23) and the reception side clock unit receive the reception side time, detect the reception side time when the signal under measurement is received, and detect the reception side time and the transmission side time from the time information reception unit A receiving side delay measuring device (20) comprising a delay calculating unit (24) for calculating a delay time of the signal under measurement from the time information transmitting unit to the time information receiving unit using
A delay measurement system comprising: The transmission-side delay measurement device includes:
A transmission side delay calculation unit that acquires a common time from the transmission side time acquisition unit and acquires a transmission side time from the transmission side clock unit and calculates a transmission side delay between the common time and the transmission side time ( 15)
A transmission side time correction unit (16) for correcting the transmission side time output from the transmission side clock unit using the transmission side delay acquired by the transmission side delay calculation unit;
With
The reception-side delay measurement device includes:
A reception side delay calculation unit that acquires a common time from the reception side time acquisition unit and acquires a reception side time from the reception side clock unit, and calculates a reception side delay between the common time and the reception side time ( 25)
A reception side time correction unit (26) for correcting the reception side time output from the reception side clock unit using the reception side delay acquired by the reception side delay calculation unit;
With
The transmission side time acquisition unit and the reception side time acquisition unit acquire a common time from the common clock source a plurality of times,
The time information transmission unit acquires the transmission side time after correction from the transmission side time correction unit, and transmits the signal under measurement with the transmission side time at the time of transmission of the signal under measurement,
The delay calculation unit receives the corrected reception side time from the reception side time correction unit, detects the reception side time at the time of reception of the signal under measurement, and detects the reception side time and the time information reception unit 2. The delay measurement system according to claim 1, wherein a delay time of the signal under measurement from the time information transmission unit to the time information reception unit is calculated using the transmission side time. The transmission-side delay measurement device includes:
A transmission side delay calculation unit that acquires a common time from the transmission side time acquisition unit and acquires a transmission side time from the transmission side clock unit and calculates a transmission side delay between the common time and the transmission side time ( 15)
The reception-side delay measurement device includes:
A reception side delay calculation unit that acquires a common time from the reception side time acquisition unit and acquires a reception side time from the reception side clock unit, and calculates a reception side delay between the common time and the reception side time ( 25)
The transmission side time acquisition unit and the reception side time acquisition unit acquire a common time from the common clock source a plurality of times,
The time information transmission unit acquires the transmission side delay from the transmission side delay calculation unit, transmits the signal under measurement further loaded with the transmission side delay,
The time information receiving unit further outputs a transmission side delay carried on the signal under measurement,
The delay calculation unit further acquires a transmission side delay from the time information reception unit to correct the transmission side time, acquires a reception side delay from the reception side delay calculation unit, and sets the reception side time. The delay time of the signal under measurement from the time information transmission unit to the time information reception unit is calculated using the corrected transmission side time and reception side time after correction. Delay measurement system. The transmission-side delay measurement device (10) and the reception-side delay measurement device (20) acquire a common time from a common clock source, clock the time with an independent oscillator, and measure the transmission-side delay periodically or according to an external instruction. A time synchronization procedure (S101) for synchronizing the transmission side time in the apparatus and the reception side time in the reception side delay measurement apparatus;
A signal-under-measurement procedure (S102) for transmitting the signal-under-measurement with the transmission-side time at the time of transmitting the signal-under-measurement from the transmission-side delay measurement device to the reception-side delay measurement device;
The delay time of the signal under measurement from the transmission side delay measurement device to the reception side delay measurement device using the reception side time at the time of reception of the signal under measurement and the transmission side time carried on the signal under measurement A delay calculation procedure to calculate (S103);
The delay measuring method which has in order. A common time from the common clock source is acquired by the transmission side delay measurement device and the reception side delay measurement device after a certain time from the time synchronization procedure, and the common time and the transmission side time acquired by the transmission side delay measurement device are obtained. A time correction that corrects the transmission side time using the transmission side delay in between and corrects the reception side time using the reception side delay between the common time acquired by the reception side delay measuring device and the reception side time A procedure (S104) is further provided between the time synchronization procedure and the measured signal transmission procedure,
In the signal under measurement transmission procedure, the signal under measurement with the transmission side time corrected in the time correction procedure is transmitted from the transmission side delay measurement device to the reception side delay measurement device,
The delay calculation procedure calculates a delay time of the signal under measurement from the transmission-side delay measurement device to the reception-side delay measurement device using the reception-side time corrected by the time correction procedure. Item 5. The delay measurement method according to Item 4. A common time from the common clock source is acquired by the transmission side delay measurement device and the reception side delay measurement device after a certain time from the time synchronization procedure, and the common time and the transmission side time acquired by the transmission side delay measurement device are obtained. A delay calculation procedure (S105) for calculating a transmission side delay between the common time acquired by the reception side delay measuring device and a reception side time (S105), Further comprising during the measured signal transmission procedure;
In the measured signal transmission procedure, the transmission side delay calculated in the delay calculation procedure is further added to the measured signal, and the measured signal is transmitted from the transmission side delay measurement device to the reception side delay measurement device. ,
In the delay calculation procedure, the transmission side time is corrected using the transmission side delay transmitted in the measured signal transmission procedure, and the reception side time is calculated using the reception side delay calculated in the delay calculation procedure. 5. The delay time of the signal under measurement from the transmission side delay measurement device to the reception side delay measurement device is calculated using the corrected transmission side time and reception side time after correction. The delay measurement method described in 1.

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