JP2022048488A - Synchronization signal converter - Google Patents

Abstract

To provide a synchronization signal converter that enables the installation of a base station even in an environment where a GPS signal, a network signal, and a broadcast wave cannot be received, and can increase the degree of freedom in system construction.SOLUTION: In a synchronization signal converter, a time information acquisition unit 35 acquires reference time information from a time reference machine 21; a synchronization signal extraction unit 33 acquires system synchronization information from broadcast information of a wireless communication system; an RTC unit 41 outputs generation time information generated on the basis of the reference time information at the timing of the system synchronization information, and generates synchronized time information synchronized with a GPS reference time; and a pseudo GPS reception signal or a network signal including the synchronization time information is generated to be output to a base station device.SELECTED DRAWING: Figure 2

Description

The present invention relates to a synchronization signal conversion device attached to a base station of a mobile communication system, and in particular, can construct a system synchronized with GPS even in an environment where GPS signals cannot be received or broadcast waves cannot be received. It relates to a synchronous signal converter that can increase the degree of freedom of construction.

[Explanation of prior art]
In TDD (Time Division Duplex) wireless systems (existing wireless communication systems) such as CDMA (Code Division Multiple Access) and WiMAX (Worldwide Interoperability for Microwave Access), the timing of communication between terminals and base stations is the same for the entire system. I need to let you. Therefore, the base station generates a synchronization signal synchronized with the GPS (Global Positioning System) reference time, controls the timing of uplink / downlink communication, and realizes a system synchronized with the GPS reference time.

[Base station device equipped with GPS receiver: Fig. 8]
Here, a base station apparatus provided with a GPS receiver will be described with reference to FIG. FIG. 8 is an explanatory diagram showing a schematic configuration of a base station device including a GPS receiver.
As shown in FIG. 8, the base station device 101 includes a GPS antenna 201 and a GPS receiver 102.
The GPS antenna 201 receives a GPS signal from a GPS satellite and outputs a GPS reception signal.
The GPS receiver 102 extracts a reference time represented by UTC (Coordinated Universal Time) from the GPS reception signal input from the GPS antenna 201, and synchronizes (time synchronization) with the reference time. To generate.
Then, the base station device 101 operates in accordance with the synchronization signal to perform communication synchronized with the GPS reference time.

Here, in the present specification, signals transmitted from each GPS satellite (satellite) are referred to as "GPS signals", and signals in a state in which GPS signals from a plurality of satellites received by the GPS antenna 201 are superimposed are referred to as "GPS signals". It shall be referred to as "GPS received signal".
That is, the GPS reception signal is a signal input to the GPS receiver 102, and the GPS receiver 102 acquires the time information synchronized with the UTC and the current position information based on the input GPS reception signal (). It is designed to be calculated).

In an environment where it is difficult to receive GPS signals, a mechanism for distributing time synchronization information via a wired network defined by IEEE1588 may be used.
Further, in the existing wireless communication system using the TDD method, the notification information transmitted from the base station to the terminal includes time synchronization information, and in the base station apparatus, another base is used as a substitute for the GPS signal. A synchronization signal may be generated using the broadcast information from the station.

[Communication system notification information]
However, in LTE / LTE-Advanced, which is the main system of mobile communication at present, and 5G (fifth generation communication), which is the next-generation system currently under consideration, the standard broadcast information from the base station is not included. Does not contain time information.
Therefore, it is difficult to use it as a substitute for GPS signals.

In LTE-Advanced, the CA (Carrier Aggregation) technology that bundles frequencies to increase speed requires synchronization between base stations, and in the new LTE-Advanced and 5G frequency allocation, the TDD method is used. It is a prerequisite.
In the TDD method, interference will occur unless transmission and reception are performed at the correct timing. Therefore, in these communication systems, although the notification information from the base station does not include the time information, the periodic signal such as the frame number which is the synchronization signal of the system is notified, and this periodic signal is the reference time of GPS. Often synchronized.
Depending on the system, the periodic signal may have a certain deviation (offset) with respect to the GPS reference time.

[Related technology]
As a prior art of the synchronous signal conversion device, there is Japanese Patent Application Laid-Open No. 2019-20499 "Synchronous signal conversion device" (Patent Document 1).
In Patent Document 1, based on the time information of the broadcast wave and the system synchronization signal of the wireless communication system synchronized with the GPS reference time, the synchronization time information synchronized with the GPS reference time is generated and the time is calculated. A synchronous signal conversion device that generates a pseudo GPS reception signal and outputs the pseudo GPS reception signal to the base station device is described.

Japanese Unexamined Patent Publication No. 2019-20499

As described above, in the LTE / LTE Advanced and 5G communication systems, since the broadcast information does not include the time information, the base station apparatus uses the broadcast information instead of the GPS signal to generate a synchronization signal. There is a problem that it is difficult to establish synchronization of a communication system in an environment where it is difficult to receive GPS signals and network signals.

It should be noted that Patent Document 1 does not describe that a pseudo GPS reception signal synchronized with the GPS reference time is generated without using the time information included in the broadcast wave.

The present invention has been made in view of the above circumstances, and even in an environment where it is difficult to receive GPS signals, network signals, and broadcast waves because the broadcast information does not include time information, it is synchronized with the GPS reference time. It is an object of the present invention to provide a synchronous signal conversion device capable of realizing a system and increasing the degree of freedom in system construction.

The present invention for solving the problems of the above-mentioned conventional example is a synchronization signal conversion device connected to a base station of a wireless communication system, receives notification information of the wireless communication system, and receives GPS reference time from the notification information. The synchronization signal acquisition unit that acquires the system synchronization signal synchronized with, the time information acquisition unit that acquires the reference time information from the time reference machine, and the generation time information generated based on the reference time information are output at the timing of the system synchronization signal. By doing so, the real-time clock unit that generates the synchronized time information synchronized with the GPS reference time and the base station can calculate the time that matches the synchronized time information based on the synchronized time information, so that the orbits of multiple satellites can be calculated. It is equipped with a GPS time information conversion unit that generates pseudo GPS reception signals including information and time information corresponding to the transmission time from each satellite, and a pseudo GPS reception signal transmission unit that outputs pseudo GPS reception signals to the base station. It is characterized by.

Further, the present invention is a synchronization signal conversion device connected to a base station of a wireless communication system, which receives notification information of the wireless communication system and acquires a system synchronization signal synchronized with a GPS reference time from the notification information. Synchronized with the GPS reference time by outputting the synchronization signal acquisition unit, the time information acquisition unit that acquires the reference time information from the time reference machine, and the generation time information generated based on the reference time information at the timing of the system synchronization signal. The real-time clock unit that generates the synchronized time information, the network signal conversion unit that generates the network signal including the synchronization time information according to the format conforming to the network standard, and the network signal transmission unit that sends the network signal to the base station. It is characterized by being prepared.

Further, the present invention is characterized in that, in the synchronization signal conversion device, the real-time clock unit generates synchronization time information using the generation time information generated based on the reference time information acquired in advance from the time reference machine. ..

Further, in the present invention, in the above-mentioned synchronization signal conversion device, the real-time clock unit generates an internal clock based on the system synchronization signal acquired in advance from the broadcast information of the wireless communication system, and instead of the system synchronization signal, the internal clock is internally generated. It is characterized by generating synchronous time information using clock timing.

Further, the present invention is characterized in that, in the synchronous signal conversion device, the real-time clock section is provided with a battery section, and when the power supply to the device is cut off, the operation is continued by the electric power from the battery section. ..

Further, the present invention is a synchronization signal conversion method in a synchronization signal conversion device connected to a base station of a wireless communication system, in which the notification information of the wireless communication system is received and synchronized with the GPS reference time from the notification information. By acquiring the synchronization signal, acquiring the reference time information from the time reference machine, and outputting the generated time information generated based on the reference time information at the timing of the system synchronization signal, the synchronization time information synchronized with the GPS reference time can be obtained. It is characterized in that it is generated and converted into a pseudo GPS reception signal that can calculate the time corresponding to the synchronization time information or a network signal including the synchronization time information and output.

According to the present invention, it is a synchronization signal conversion device connected to a base station of a wireless communication system, receives notification information of the wireless communication system, and acquires a system synchronization signal synchronized with a GPS reference time from the notification information. Synchronized with the GPS reference time by outputting the synchronization signal acquisition unit, the time information acquisition unit that acquires the reference time information from the time reference machine, and the generation time information generated based on the reference time information at the timing of the system synchronization signal. The real-time clock unit that generates the synchronized time information and the time that matches the synchronized time information can be calculated by the base station based on the synchronized time information, so that the orbit information of multiple satellites and the transmission time from each satellite can be used. Since it is a synchronous signal conversion device equipped with a GPS time information conversion unit that generates a pseudo GPS reception signal including corresponding time information and a pseudo GPS reception signal transmission unit that outputs a pseudo GPS reception signal to a base station, it is a GPS signal. Even in an environment where it is not possible to receive broadcast waves, the base station can calculate time information synchronized with the GPS reference time from the pseudo GPS reception signal and generate a synchronization signal, realizing a wireless communication system synchronized with GPS. There is an effect that can be done.

Further, according to the present invention, it is a synchronization signal conversion device connected to a base station of a wireless communication system, and receives notification information of the wireless communication system, and obtains a system synchronization signal synchronized with the GPS reference time from the notification information. GPS reference time by outputting the synchronization signal acquisition unit to be acquired, the time information acquisition unit to acquire reference time information from the time reference machine, and the generation time information generated based on the reference time information at the timing of the system synchronization signal. A real-time clock unit that generates synchronized time information synchronized with, a network signal conversion unit that generates network signals including synchronized time information according to a format compliant with network standards, and a network signal transmission unit that sends network signals to base stations. Since it is a synchronized signal conversion device equipped with, the base station extracts the synchronized time information synchronized with the GPS reference time from the network signal and outputs the synchronized signal even in an environment where GPS signals and broadcast waves cannot be received. There is an effect that it can be generated and a wireless communication system synchronized with GPS can be realized.

Further, according to the present invention, the real-time clock unit is the above-mentioned synchronization signal conversion device that generates synchronization time information using the generation time information generated based on the reference time information acquired in advance from the time reference machine. If the time reference machine is connected and the reference time information is acquired at the time of installation, then the time reference machine can be removed and the synchronization time information can be generated using the generation time information generated based on the reference time information. It has the effect of reducing work and operation costs.

Further, according to the present invention, the real-time clock unit generates an internal clock based on a system synchronization signal acquired in advance from the broadcast information of the wireless communication system, and uses the timing of the internal clock instead of the system synchronization signal. Since the above-mentioned synchronization signal converter is used to generate synchronization time information, even if the radio wave environment deteriorates and the system synchronization signal cannot be obtained, synchronization time information can be generated based on the internal clock, and GPS can be generated with a certain accuracy. It has the effect of maintaining the synchronization state with respect to.

Further, according to the present invention, the real-time clock unit is provided with a battery unit, and when the power supply to the device is cut off, the real-time clock unit is the above-mentioned synchronous signal conversion device that continues to operate with the power from the battery unit. Even if the power is not supplied to, the battery unit can continue the operation of the real-time clock unit, maintain the synchronization state with a certain accuracy, and connect the time reference machine when the power is restored. However, by inputting the system synchronization signal, highly accurate synchronization time information can be generated again, and there is an effect that the restart can be easily performed and the maintenance work can be greatly reduced.

Further, according to the present invention, it is a synchronization signal conversion method in a synchronization signal conversion device connected to a base station of a wireless communication system, and receives notification information of the wireless communication system and synchronizes the notification information with a GPS reference time. Synchronized time synchronized with GPS reference time by acquiring the system synchronization signal, acquiring reference time information from the time reference machine, and outputting the generated time information generated based on the reference time information at the timing of the system synchronization signal. Since the synchronization signal conversion method is used to generate information and convert it into a pseudo GPS reception signal that can calculate the time that matches the synchronization time information or a network signal that includes synchronization time information and output it, GPS signals and broadcast waves cannot be received. Even in an environment, the base station can generate a synchronization signal by extracting the synchronization time information synchronized with the GPS reference time from the pseudo GPS reception signal or the network signal, and can realize a wireless communication system synchronized with GPS. There is an effect that can be done.

It is explanatory drawing which shows the outline of the 1st synchronous signal conversion apparatus of this invention. It is a block diagram of the composition of the 1st synchronization signal conversion apparatus. It is an operation state explanatory diagram of the 2nd synchronization signal conversion apparatus. It is an operation state explanatory diagram of the 3rd synchronization signal conversion apparatus. It is an operation state explanatory diagram of the 4th synchronization signal conversion apparatus. It is explanatory drawing which shows the outline of the 5th synchronization signal conversion apparatus. It is a block diagram of the 5th synchronization signal conversion apparatus. It is explanatory drawing which shows the schematic structure of the base station apparatus provided with the GPS receiver.

An embodiment of the present invention will be described with reference to the drawings.
[Outline of Embodiment]
The synchronization signal conversion device (the present synchronization signal conversion device) according to the embodiment of the present invention is a system synchronization signal (for example, a frame number) synchronized with a GPS reference time from the broadcast information transmitted from the base station of the mobile communication system. ), And the time information acquired from the time reference machine equipped with an atomic clock or the like is corrected at the timing of the system synchronization signal to generate time information synchronized with the GPS reference time. In response to this, a pseudo GPS reception signal including orbit information of a plurality of satellites and time information corresponding to the transmission time from each satellite is generated, and the receiving side device (for example, a base station device) equipped with a GPS receiver is used. Even if the receiving device is in an environment where GPS signals and broadcast waves cannot be received, it can generate a synchronization signal synchronized with the GPS reference time based on the pseudo GPS reception signal to realize a communication system, and can construct a system. It is possible to increase the degree of freedom.

In addition, this synchronization signal conversion device extracts a system synchronization signal (frame number) synchronized with a reference time based on a GPS signal from the broadcast information transmitted from the base station of the mobile communication system, and is equipped with an atomic clock or the like. By correcting the time information acquired from the time reference machine at the timing of the system synchronization signal, time information synchronized with the GPS reference time is generated, and the network including the time information is based on the format of the wired network. A signal is generated and output to a receiving device equipped with a wired network interface (for example, a base station device), and even a receiving device in an environment where GPS signals, network signals and broadcast waves cannot be received is a wired network. It is possible to realize a communication system by generating a synchronization signal synchronized with the GPS reference time based on the time information received by the interface of the above, and it is possible to increase the degree of freedom in system construction.

In the following embodiment, an example applied to an LTE / LTE-Advanced or 5G system as a wireless system will be described, but the synchronous signal conversion device according to the embodiment of the present invention is LTE / LTE-Advanced. Alternatively, it is not specialized for 5G, and is applicable to time synchronization in the entire system including a system synchronization signal synchronized with the GPS reference time without including time information in the broadcast information.

[Embodiment of the present synchronous signal conversion device]
The configuration and operation of the synchronous signal conversion device will be described as the first embodiment to the fifth embodiment.
[Summary of Synchronous Signal Converter Device According to First Embodiment: FIG. 1]
The outline of the synchronization signal conversion device (first synchronization signal conversion device) according to the first embodiment will be described with reference to FIG. FIG. 1 is an explanatory diagram showing an outline of the first synchronous signal conversion device of the present invention.
As shown in FIG. 1, the first synchronization signal conversion device 11 is used by being connected to a base station device 101 provided with a GPS receiver 102 similar to that of FIG. 8, and supplies a pseudo GPS signal to the base station device 101. It is something to do.

Specifically, the first synchronization signal conversion device 11 includes a receiving antenna 31 for receiving an LTE / LTE-Advanced or 5G (indicated as an LTE signal or the like in the figure) radio signal, and a time reference machine 21 is connected to the receiving antenna 31. ing.
The time reference machine 21 is equipped with an atomic clock (atomic frequency standard device) or the like, and supplies highly accurate time information to the first synchronization signal conversion device 11.
Then, the first synchronization signal conversion device 11 generates a pseudo GPS reception signal based on the LTE / LTE-Advanced or 5G radio signal and the time information from the time reference machine 21, and outputs the pseudo GPS reception signal to the base station device 101. It is something to do.

The base station device 101 includes a GPS receiver 102, but does not have a GPS antenna. Then, the GPS receiver 102 inputs a pseudo GPS reception signal from the first synchronization signal conversion device 1 instead of the GPS reception signal, acquires time information synchronized with the GPS reference time, and synchronizes based on the time information. Generate a signal.

Here, in the pseudo GPS reception signal generated by the synchronization signal conversion device of the present invention, the GPS receiver 102 of the connected base station device 101 can acquire accurate time information and correct position information synchronized with the UTC. It is a signal generated as described above, and is a signal including orbit information corresponding to a plurality of satellites and time information corresponding to the transmission time of each satellite, as in the case of receiving GPS signals from a plurality of satellites.
That is, when the pseudo GPS reception signal is input, the GPS receiver 102 of the base station device 101 recognizes that the GPS signals from a plurality of satellites are superimposed and input, and inputs the original GPS reception signal. It operates in the same way as in the case.
Here, "time information synchronized with the GPS reference time" is used as a synonym for "time information synchronized with UTC".

[Configuration of First Synchronous Signal Converter: FIG. 2]
The configuration of the first synchronization signal conversion device 11 will be described with reference to FIG. FIG. 2 is a block diagram of the configuration of the first synchronization signal conversion device.
As shown in FIG. 2, the first synchronization signal conversion device 11 includes a reception antenna 31, a radio reception unit 32, a synchronization signal extraction unit 33, a time information reception unit 34, a time information acquisition unit 35, and a GPS. It includes a time information conversion unit 36, a pseudo GPS reception signal transmission unit 37, and a real-time clock (RTC: Real Time Clock) unit 41.

Each part of the first synchronization signal conversion device 11 will be described.
The receiving antenna 31 is an antenna that receives radio waves from an LTE, LTE-Advanced or 5G base station.
The radio receiving unit 32 down-converts and demodulates the radio signal.

The synchronization signal extraction unit 33 extracts a system synchronization signal from the broadcast information included in the received signal of the wireless communication system and outputs the system synchronization signal to the RTC unit 41. Examples of the system synchronization signal include a signal indicating a specific frame number and the like. The system synchronization signal is synchronized with the timing of the GPS reference time.
Depending on the type of wireless communication system, the system synchronization signal may have a certain offset from the GPS reference time.

The time information receiving unit 34 receives the time information from the time reference machine 21.
The time information acquisition unit 35 acquires time information from the input signal and outputs it to the RTC unit 41. Although the acquired time information is highly accurate, it is not always exactly synchronized with the GPS reference time.

The RTC unit 41 is a characteristic part of the first synchronization signal conversion device, and inputs system synchronization information from the synchronization signal extraction unit 33 and time information from the time information acquisition unit 35, and time information based on these. Is output according to the timing of the system synchronization information to generate time information (synchronization time information) synchronized with the GPS reference time.
The configuration and operation of the RTC unit 41 will be described later.

The GPS time information conversion unit 36 generates a pseudo GPS reception signal based on the synchronization time information input from the RTC unit 41.
Specifically, the GPS time information conversion unit 36 pseudo-calculates GPS signals from a plurality of satellites so as to correspond to the synchronized time information, and a GPS reception signal (pseudo) as if a plurality of GPS signals overlap. GPS reception signal) is generated.

As described above, the pseudo GPS reception signal includes the orbit information of a plurality of satellites and the time information corresponding to the transmission time from each satellite, which is generated so that the synchronization time information is calculated by the receiving side device. The GPS receiver 102 of the base station apparatus 10 can calculate the same time information as the synchronization time information based on the received pseudo GPS reception signal to generate the synchronization signal and calculate the position. It becomes.

The pseudo GPS signal is the same as the signal generated by the GPS simulator used for testing the GPS receiver. For example, Keysight Technologies, Inc., published on January 6, 2015, "Keysight Technologies GPS Receiver Test". "It is described in.

The pseudo GPS reception signal transmission unit 37 outputs the pseudo GPS reception signal output from the GPS time information conversion unit 36 to the connected base station device 101.

[Operation of the first synchronization signal converter: FIGS. 1 and 2]
The operation of the first synchronization signal conversion device will be briefly described with reference to FIGS. 1 and 2.
In the first synchronous signal conversion device 11, the receiving antenna 31 receives radio waves from a base station of an LTE, LTE-Advanced or 5G wireless communication system.
Further, the time information from the time reference machine 21 is received by the time information receiving unit 34.
Then, the synchronization signal extraction unit 33 acquires the system synchronization signal from the signal of the wireless communication system, and the time information acquisition unit 35 acquires the time information. The system synchronization signal is synchronized with the timing of the GPS reference time.

Then, the RTC unit 41 corrects the time information so as to synchronize with the GPS reference time based on the system synchronization signal, and outputs the time information as synchronization time information. Then, the GPS time information conversion unit 36 generates a pseudo GPS reception signal so that the base station device 101 on the receiving side calculates the same time as the synchronization time information, and the pseudo GPS signal transmission 37 generates the pseudo GPS. The received signal is output.
In this way, the operation in the first synchronization signal conversion device is performed.

[Structure of RTC unit 41: FIG. 2]
Next, the configuration of the RTC unit 41 will be described with reference to FIG.
As shown in FIG. 2, the RTC unit 41 includes a time setting unit 42, a clock setting unit 43, a clock output unit 44, a time count-up unit 45, and a battery unit 46.
The RTC unit 41 basically performs a self-propelled operation based on the internal clock, and the time count-up unit 45 holds the time information (correction time information) from the time setting unit 42, and the clock output unit. By outputting the retained correction time information according to the timing from 44, the time information (synchronized time information) synchronized with the GPS reference time is generated. This operation will be described later.
Further, the RTC unit 41 can continue to operate by receiving power supply from the internal battery unit 46 even when the device is not connected to the power supply.

Then, in the RTC unit 41, when the system synchronization signal is input from the receiving antenna 31, the clock setting unit 43 corrects the timing, and when the time information is input from the time reference machine 21, the time is set. The internal time information is corrected by the unit 42.

By performing the self-propelled operation of the RTC unit 41, even if the radio wave from the base station of the wireless communication system does not sufficiently reach, the RTC unit 41 can output the synchronization time information without interruption.

Each part of the RTC part 41 will be specifically described.
The clock setting unit 43 converts the system synchronization signal input from the synchronization signal extraction unit 33 into a clock.
Specifically, the clock setting unit 43 is a frequency generation circuit including a VCXO (Voltage Controlled Crystal Oscillator), a TCXO (Temperature Compensated Crystal Oscillator), etc., and is used as a system synchronization signal. A self-propelled signal (self-propelled clock) of 1PPS that counts the timing based on the self-propelled signal is generated.
At that time, if the system synchronization signal has a known offset with respect to the GPS reference time, the clock setting unit 43 generates a self-propelled clock corrected by the offset.
Further, the clock setting unit 43 detects whether or not a system synchronization signal has been input, outputs a self-propelled clock if it is not input, and corrects the self-propelled clock with the system synchronization signal if it is input. Output.

The clock output unit 44 outputs the synchronization timing (timing signal) to the time count-up unit 45 every second based on the self-propelled clock from the clock setting unit 43.
That is, when the system synchronization signal is normally input, the clock setting unit 43 and the clock output unit 44 output a 1PPS timing signal synchronized with the GPS reference time.
As a result, even if the system synchronization signal has an offset with respect to the GPS reference time, or if the self-propelled state is prolonged and the synchronization timing output from the clock output unit 44 shifts, the system synchronization signal can be acquired again. The correction can be made.

The time setting unit 42 generates independent time information (internal time information) by the self-propelled clock, and outputs the corrected time information to which the specific time is added to the time count-up unit 45. The correction time information corresponds to the generation time information described in the claims.

The specific time is a time to be added in order to perform a process of generating synchronized time information synchronized with the GPS reference time from the internal time information.
Specifically, the specific time is set to be larger than the maximum time assumed as the deviation between the time information input to the time setting unit 42 and the GPS reference time, and is set to, for example, 0.5 seconds.

Further, when the time information (reference time information) from the time reference machine 21 is input, the time setting unit 42 updates the internal time information with the input reference time information.
As a result, when the reference time information is normally input, the time setting unit 42 outputs the correction time information obtained by adding the specific time to the reference time information.

The time count-up unit 45 holds the correction time information set by the time setting unit 42, and also stores the held correction time information according to the clock (synchronization timing) output from the clock output unit 44 by the GPS time information conversion unit. Output to 36 (count up the time).
That is, the time count-up unit 45 holds the correction time information input one after another from the time setting unit 42, and when the synchronization timing is input from the clock output unit 44, the correction time information held at that time is held. Is output.

As described above, the corrected time information is time information obtained by adding a specific time to the internal time information, and even if the reference time information deviates from the GPS reference time or it takes time to process, the added specific time is used. It can be sufficiently absorbed, and by outputting the corrected time information in accordance with the synchronization timing, the time information synchronized with the GPS reference time can be obtained. Since the specific operation is the same as that of Patent Document 1, the description thereof will be omitted.
As a result, the time count-up unit 45 outputs time information (synchronized time information) synchronized with the GPS reference time every second.

The battery unit 46 supplies power to each unit of the RTC unit 41.
The battery unit 46 monitors the device power supply of the synchronization signal conversion device 11, and when it detects that the power supply is cut off, it supplies power to each unit of the RTC unit 41 to continue the operation of the RTC unit 41. ..

[Effect of the first synchronization signal converter]
According to the first synchronization signal conversion device, the synchronization signal extraction unit 32 extracts the system synchronization signal synchronized with the GPS reference time from the broadcast information of the wireless communication system, and the time information acquisition unit 35 is the time reference machine. The time information from 21 is acquired, the time setting unit 42 of the RTC unit 41 outputs the correction time information in which the time information is advanced by a specific time, and the time count-up unit 45 holds the correction time information and clocks. By outputting the retained correction time information according to the timing synchronized with the system synchronization signal from the output unit 44, the synchronized time information synchronized with the GPS reference time is generated, and the GPS time information conversion unit 36 is on the receiving side. A pseudo GPS reception signal including orbit information and time information of a plurality of satellites is generated so that the same time as the synchronization time information is calculated, and the pseudo GPS reception signal transmission unit 37 is a base equipped with a GPS receiver 102. Since the output is made to the station device 101, it is possible to generate a pseudo GPS reception signal synchronized with the GPS reference time even in an environment where the broadcast wave cannot be received in addition to the GPS signal, and the base station device 101 can generate a pseudo GPS reception signal. It is possible to generate a synchronized signal by calculating time information synchronized with the GPS reference time from the GPS received signal, and there is an effect that a wireless communication system synchronized with GPS can be realized.

Further, according to the first synchronization signal conversion device, the RTC unit 41 normally operates using the synchronization clock of the self-propelled clock setting unit 43 and the internal time information of the time setting unit 42, and operates from the base station to the system. Since the synchronization timing is corrected when the synchronization signal is normally received and the internal time information is updated when the time information is normally received from the time reference machine 21, the internal time information is updated even when the time reference machine 21 is not connected. Further, there is an effect that the first synchronization signal conversion device can be used even in an environment of a weak electric field where the radio waves of the wireless communication system cannot be received satisfactorily.

[Operational mode of the first synchronous signal conversion device]
The first synchronous signal conversion device described above can be operated in various forms depending on the situation, in addition to the operation modes shown in FIG.
As shown in FIG. 2, the operation state in which the system synchronization signal is connected to the time reference machine 21 and can be acquired by the reception antenna 31, the wireless reception unit 32, and the synchronization signal extraction unit 33 is set as the first operation mode. The second to fourth operation modes will be described as the second to fourth embodiments.
By enabling various operation modes in this way, the first synchronization signal conversion device can be operated in the optimum form according to the presence / absence of the time reference machine 21 and the state of the communication environment.

[Synchronous signal conversion device according to the second embodiment: FIG. 3]
Next, the synchronization signal conversion device (second synchronization signal conversion device) according to the second embodiment of the present invention will be described with reference to FIG. The second synchronization signal conversion device corresponds to a state in which the first synchronization signal conversion device is operated in the second operation mode. FIG. 3 is an operational state explanatory diagram of the second synchronization signal conversion device.

The second synchronization signal conversion device generates synchronization time information in a state where the time reference machine 21 is not connected.
Note that FIG. 3 shows only the part related to the operation in the state where the time reference machine 21 is separated from the second synchronization signal conversion device, and the overall configuration of the device is the same as that in FIG. It includes a time information receiving unit 34 and a time information acquisition unit 35.

Although the time reference machine 21 has highly accurate time information, it is equipped with an atomic clock or the like, and is often expensive or has a large device volume.
Therefore, in the second synchronization signal conversion device, the time reference machine is temporarily connected when the device is installed, and then the time reference machine 21 is not connected.

As shown in FIG. 3, the second synchronization signal conversion device 12 does not connect to the time reference machine 21 and generates synchronization time information using the internal time held by the time setting unit 42 of the RTC unit 41. , A pseudo GPS reception signal that calculates a time equivalent to the synchronization time information is generated and provided to the base station apparatus 101.

The time set from the time reference machine 21 is set as the internal time information in the time setting unit 42, and the time setting unit 42 outputs the correction time information obtained by adding the specific time to the internal time information, and outputs the RTC unit. In 41, it is held while being updated sequentially.

Further, the receiving antenna 31, the wireless receiving unit 32, and the synchronization signal extraction unit 33 receive the LTE signal and the like, and extract the synchronization signal of the communication system.
Therefore, even if the time reference machine 21 is not connected, the time count-up unit 45 outputs (counts up) the corrected time information according to the timing from the clock output unit 44, thereby accurately synchronizing with the GPS reference time. It is possible to generate a pseudo GPS reception signal.

[Effect of the second embodiment]
According to the second synchronization signal conversion device, the time setting unit 42 holds the time set by the time reference machine 21 as internal time information, generates correction time information based on the internal time information, and counts up the time. By outputting the correction time information according to the timing of the clock extracted from the system synchronization signal of the communication system such as LTE, the unit 45 can generate the synchronization time information synchronized with the GPS reference time, and based on this, the pseudo GPS. The received signal can be generated and output to the base station device 101, and a highly accurate pseudo GPS reception signal can be generated even if the time reference machine 21 is not connected. Only when the time reference machine 21 is installed in the synchronization signal conversion device. By using it, there is an effect that the work can be reduced and the cost can be reduced.

[Synchronous signal conversion device according to the third embodiment: FIG. 4]
Next, the synchronization signal conversion device (third synchronization signal conversion device) according to the third embodiment of the present invention will be described with reference to FIG. The third synchronization signal conversion device corresponds to a state in which the first synchronization signal conversion device is operated in the third operation mode. FIG. 4 is an operational state explanatory diagram of the third synchronization signal conversion device.
The third synchronization signal conversion device does not use the time reference machine 21, and shows an operating state when the system synchronization signal cannot be extracted.

As described above, the clock setting unit 43 of the RTC unit 41 generates a self-propelled clock (internal clock) based on the system synchronization signal input so far. That is, the clock set based on the system synchronization signal is held, and the synchronization state with the timing based on the GPS reference time can be maintained with a certain accuracy.

Therefore, even if the radio wave environment deteriorates and the system synchronization signal of the communication system such as LTE cannot be obtained via the reception antenna 31, the wireless reception unit 32, and the synchronization signal extraction unit 33, the clock setting unit 43 holds the signal. The time count-up unit 45 can output the synchronized time information by outputting the corrected time information from the time setting unit 42 based on the clock, and can generate a pseudo GPS reception signal based on the synchronized time information. be.

However, in the operation mode of the third synchronization signal conversion device, since the synchronization signal of the communication system cannot be extracted, the synchronization accuracy of the pseudo GPS reception signal is not perfect.
When the radio wave environment is improved, the configuration of the second synchronization signal conversion device shown in FIG. 3 is established again, the system synchronization signal is extracted again, and the clock setting unit 43 detects the input of the system synchronization signal and self. The running clock can be corrected, and a highly accurate pseudo GPS reception signal can be generated again.

[Effect of the third embodiment]
According to the third synchronization signal conversion device, the time setting unit 42 holds the time set by the time reference machine 21 as internal time information, generates correction time information based on the internal time information, and sets the clock. The unit 43 generates a self-propelled clock based on the system synchronization signal input so far, and the time count-up unit 45 outputs the corrected time information according to the timing of the self-propelled clock, so that the accuracy is constant. Synchronized time information synchronized with the GPS reference time can be generated, a pseudo GPS reception signal can be generated and output to the base station device 101, the time reference machine 21 is not connected, the communication environment deteriorates, and the system synchronization signal is extracted. Even if it cannot be done, there is an effect that a pseudo GPS reception signal with a certain accuracy can be generated.

[Synchronous signal conversion device according to the fourth embodiment: FIG. 5]
Next, the synchronization signal conversion device (fourth synchronization signal conversion device) according to the fourth embodiment of the present invention will be described with reference to FIG. The fourth synchronization signal conversion device corresponds to a state in which the first synchronization signal conversion device is operated in the fourth operation mode. FIG. 5 is an operational state explanatory diagram of the fourth synchronization signal conversion device.
Although FIG. 5 does not describe a part other than the part that operates in the fourth operation mode, the overall configuration of the device is the same as that of the first synchronization signal conversion device.
The fourth synchronization signal conversion device shows a state in which the device power supply of the synchronization signal conversion device is cut off due to a failure of the power supply equipment or the like, and only the RTC unit 41 operates.

Normally, when the device is restarted after the power is turned off, if the time reference machine 21 is prepared again to receive the reference time, a large-scale work is required.
Therefore, in the fourth synchronization signal conversion device, the battery unit 46 inside the RTC unit 41 is discharged, so that only the RTC unit 41 continues to operate, facilitating restart.

That is, in the fourth synchronous signal conversion device, since the power of the device is turned off, the output of the pseudo GPS reception signal is stopped, but the time setting unit 42 continues to generate the internal time information, and the clock setting unit 43. Continues to generate the self-propelled clock, and the time count-up unit 45 continues to generate the synchronized time information.
As a result, the fourth synchronization signal conversion device can maintain the state in which the internal synchronization state is synchronized with the GPS reference time with a certain accuracy even after the power of the device is turned off.

Then, when the power supply of the device is restored, the configuration is the same as that of the second synchronization signal conversion device shown in FIG. 3, and the clock setting unit 43 is corrected by using the system synchronization signal of the communication system, and the accuracy is high again. Synchronous time information can be generated.

[Effect of the fourth embodiment]
According to the fourth synchronization signal conversion device, when the power of the device is turned off, the RTC unit 41 operates by receiving the power supply from the battery unit 46, and maintains the generation of the internal time information and the self-propelled clock. Therefore, the synchronization state can be maintained with a certain accuracy, and when the power is restored, the synchronization time information with high accuracy can be obtained again by inputting the system synchronization signal without connecting the time reference machine 21. It can be generated, and it has the effect of easily restarting and greatly reducing maintenance work.

[Summary of Synchronous Signal Converter Device According to Fifth Embodiment: FIG. 6]
Next, the outline of the synchronization signal conversion device (fifth synchronization signal conversion device) according to the fifth embodiment of the present invention will be described with reference to FIG. FIG. 6 is an explanatory diagram showing an outline of the fifth synchronization signal conversion device.
As shown in FIG. 6, the fifth synchronization signal conversion device 51, like the first synchronization signal conversion device, is an LTE / LTE-Advanced or 5G radio system signal and time information from the time reference machine 21. Based on the above, time information synchronized with the GPS reference time is generated and provided to the base station device 103 installed in an environment where GPS signals cannot be received via a specific wired network (for example, IEEE1588).

Here, the base station apparatus 103 includes an interface (network interface) 104 of a specific wired network (for example, IEEE1588).
Then, the fifth synchronization signal conversion device 51 converts the time information (synchronization time information) synchronized with the GPS reference time into a network synchronization signal and sends it to the base station device 103.
The base station apparatus 103 extracts a synchronization signal from the network signal input via the network interface 104 and uses it as a reference clock.

[Configuration of Fifth Synchronous Signal Converter: FIG. 7]
The configuration of the fifth synchronization signal conversion device 51 will be described with reference to FIG. 7. FIG. 7 is a block diagram of a fifth synchronization signal converter.
As shown in FIG. 7, the fifth synchronization signal conversion device 51 includes a reception antenna 31, a wireless reception unit 32, a synchronization signal extraction unit 33, a time information reception unit 34, a time information acquisition unit 35, and an RTC. A unit 41, a network signal conversion unit 61, and a network signal transmission unit 62 are provided.
Here, since the components other than the network signal conversion unit 61 and the network signal transmission unit 62 have the same configuration and operation as the first synchronization signal conversion device, the description thereof will be omitted.

The characteristic portion of the fifth synchronization signal conversion device 51 will be described.
The network signal conversion unit 61 inputs synchronization time information synchronized with the GPS reference time output from the time count-up unit 45 of the RTC unit 41, and converts it into a predetermined format conforming to a network standard such as IEEE1588. , Generates a network signal containing the sync time information.

The network signal transmission unit 62 transmits the network signal from the network signal conversion unit 61 to the base station apparatus 103.
The base station apparatus 103 extracts synchronization time information from the network signal received via the network interface 104, generates a synchronization signal (reference clock) from the synchronization time information, and realizes communication.

As a result, even if the base station device 103 is installed in an environment that does not have a GPS receiver and cannot receive network signals compliant with IEEE1588 or the like, the network signal output by the fifth synchronization signal conversion device can be used. It is possible to generate a reference clock by extracting synchronization time information synchronized with the GPS reference time.

[Effect of the fifth synchronization signal converter]
According to the fifth synchronization signal conversion device, the RTC unit 41 corrects the time information according to the system synchronization signal by using the system synchronization signal synchronized with the GPS reference time and the time information from the time reference machine 21. By doing so, the synchronization time information synchronized with the GPS reference time is generated, the network signal conversion unit 61 generates a network signal including the synchronization time information according to the network format such as IEEE1588, and the network signal transmission unit 62 Since the network signal is output to the base station device 103 provided with the network interface 104, the GPS receiver is installed in an environment where the broadcast wave does not reach and the network signal conforming to IEEE1588 or the like cannot be received. Even if the base station device 103 is not provided, it can receive the network signal from the fifth synchronization signal conversion device 51, extract the synchronization time information synchronized with the GPS reference time, and use it as the reference clock. It has the effect of increasing the degree of freedom in system construction.

Further, the fifth synchronization signal conversion device can also be operated in the same second to fourth operation modes as the first synchronization signal conversion device, and is operated in the optimum operation mode depending on the situation. There is an effect that can be done.

The present invention is particularly suitable for a synchronized signal conversion device capable of constructing a system using time information synchronized with GPS even in an area where GPS signals and broadcast waves cannot be received, and increasing the degree of freedom in system construction. There is.

11, 12, 13, 14, 51 ... Synchronous signal converter, 21 ... Time reference machine, 31,201 ... Receiving antenna, 32 ... Wireless receiver, 33 ... Synchronous signal extraction unit, 36 ... GPS time information conversion unit, 37 ... Pseudo GPS reception signal transmission unit, 41 ... RTC (real-time clock) unit, 42 ... Time setting unit, 43 ... Clock setting unit, 44 ... Clock output unit, 45 ... Time count-up unit, 46 ... Battery unit, 61 ... Network Signal conversion unit, 62 ... Network signal transmission unit, 101, 103 ... Base station equipment, 102 ... GPS receiver, 103 ... Network interface

Claims (6)

A synchronous signal converter connected to a base station of a wireless communication system.
A synchronization signal acquisition unit that receives notification information of the wireless communication system and acquires a system synchronization signal synchronized with the GPS reference time from the notification information.
The time information acquisition unit that acquires reference time information from the time reference machine,
A real-time clock unit that generates synchronization time information synchronized with the GPS reference time by outputting the generation time information generated based on the reference time information at the timing of the system synchronization signal.
Pseudo GPS including orbit information of a plurality of satellites and time information corresponding to the transmission time from each satellite so that the base station can calculate the time corresponding to the synchronization time information based on the synchronization time information. GPS time information conversion unit that generates received signals,
A synchronous signal conversion device including a pseudo GPS reception signal transmission unit that outputs the pseudo GPS reception signal to the base station. A synchronous signal converter connected to a base station of a wireless communication system.
A synchronization signal acquisition unit that receives notification information of the wireless communication system and acquires a system synchronization signal synchronized with the GPS reference time from the notification information.
The time information acquisition unit that acquires reference time information from the time reference machine,
A real-time clock unit that generates synchronization time information synchronized with the GPS reference time by outputting the generation time information generated based on the reference time information at the timing of the system synchronization signal.
A network signal conversion unit that generates a network signal including the synchronization time information according to a format conforming to the network standard.
A synchronous signal conversion device including a network signal transmission unit that transmits the network signal to the base station. The synchronization signal conversion device according to claim 1 or 2, wherein the real-time clock unit generates synchronization time information using the generation time information generated based on the reference time information acquired in advance from the time reference machine. The real-time clock unit generates an internal clock based on a system synchronization signal acquired in advance from the broadcast information of the wireless communication system, and generates synchronization time information using the timing of the internal clock instead of the system synchronization signal. The synchronization signal conversion device according to any one of claims 1 to 3, wherein the synchronization signal conversion device is characterized. The synchronization signal conversion device according to claim 3 or 4, wherein the real-time clock unit includes a battery unit, and when the power supply to the device is cut off, the real-time clock unit continues to operate with the electric power from the battery unit. It is a synchronization signal conversion method in a synchronization signal conversion device connected to a base station of a wireless communication system.
The generation that received the notification information of the wireless communication system, acquired the system synchronization signal synchronized with the GPS reference time from the notification information, acquired the reference time information from the time reference machine, and generated based on the reference time information. By outputting the time information at the timing of the system synchronization signal, the synchronization time information synchronized with the GPS reference time is generated, and the pseudo GPS reception signal or the synchronization time information capable of calculating the time matching the synchronization time information is obtained. A synchronization signal conversion method characterized in that it is converted into a network signal including it and output.

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