JP7480011B2 - Communication device - Google Patents

Description

The present invention relates to a communication device.

The method of communication in a wireless communication system described in Patent Document 1 includes a determining step and a communicating step. The determining step determines a measure of communication quality of at least one of a first communication channel and a second communication channel. The communicating step communicates through one of the first communication channel or the second communication channel based on the measure of communication quality of one communication channel. In the wireless communication system, a mobile terminal is controlled to communicate with a base station through a communication channel selected based on the measure of communication quality (strength of a received signal).

JP 2002-530932 A

However, in the wireless communication system described in Patent Document 1, communication between a communication unit such as that in a mobile terminal and a base station may not be successful. In other words, even if the communication quality (strength of the received signal) meets the criteria, the communication unit may not be able to communicate with the base station.

The present invention has been made in consideration of the above problems, and aims to provide a communication device that enables communication between a communication unit and a base station and can prevent the meter measurement results from being unable to be transmitted to a server.

According to one aspect of the present invention, a communication device includes a communication unit, a communication determination unit, a switching unit, and a communication control unit. The communication unit communicates with one of a plurality of first base stations that emit radio waves in a first frequency band. The communication determination unit determines whether communication between the communication unit and one of the plurality of first base stations is successful. The switching unit switches the frequency band of radio waves transmitted and received by the communication unit to a second frequency band different from the first frequency band based on a determination result of the communication determination unit. The communication control unit controls the communication unit so that the communication unit communicates with one of a plurality of second base stations that emit radio waves in the second frequency band.

The communication device of the present invention can prevent the meter measurement results from being unable to be transmitted to the server.

1 is a block diagram showing a configuration of a telemetry system according to an embodiment of the present invention. 1 is a diagram illustrating a communication device and a plurality of base stations according to an embodiment of the present invention. FIG. 2 is another diagram showing a communication device and a plurality of base stations according to the embodiment. 4 shows a flowchart of a process executed by a control unit of the communication device according to the present embodiment. 6 is a flowchart showing a fixing process executed by a control unit of the communication device according to the embodiment.

Embodiments of the present invention will be described below with reference to the drawings. Note that in the drawings, the same or corresponding parts will be given the same reference symbols and descriptions will not be repeated.

A telemetry system 100 according to a first embodiment of the present invention will be described with reference to FIG. 1. FIG. 1 is a block diagram showing the configuration of the telemetry system 100.

As shown in FIG. 1, the telemeter system 100 includes a communication device 1, a meter 2, a server 3, and a base station B. In the first embodiment, the telemeter system 100 includes multiple communication devices 1, multiple meters 2, multiple servers 3, and multiple base stations B. The telemeter system 100 is a system that collects information indicating the measurement results of the meter 2. More specifically, the telemeter system 100 is a system in which the communication device 1 transmits information indicating the measurement results of the meter 2 to the base station B, and causes the base station B to collect the information indicating the measurement results. The server 3 and the base station B are, for example, a center system.

Base station B emits radio waves in a specific frequency band. The multiple base stations B emit radio waves in different frequency bands. The multiple base stations B include base station BA, base station BB, base station BC, and base station BD.

Base station BA emits radio waves in a first frequency band. Base station BB emits radio waves in the first frequency band. Base station BA and base station BB are examples of a "first base station." Base station BC emits radio waves in a second frequency band. Base station BD emits radio waves in the second frequency band. Base station BC and base station BD are examples of a "second base station."

Base station B performs information control for communication device 1.

The server 3 stores the measurement values collected by each of the multiple base stations B. The server 3 is, for example, a database server. The server 3 collects information indicating the measurement results of the meter 2, for example, via the base station B and the communication device 1.

The server 3 and the multiple base stations B are connected to a first network N1. The first network N1 includes, for example, the Internet, a LAN (Local Area Network), a public telephone network, and a short-range wireless network. Various communication devices (for example, routers, bridges, access points, hubs, and repeaters) are connected to the first network N1.

Meter 2 is a measuring device related to resources or energy. Meter 2 measures, for example, gas, water, or electricity. Meter 2 is installed for each consumer, such as a private home, a company, or various facilities. That is, meter 2 is a measuring device that measures, for example, the amount of gas, water, or electricity used, and outputs a measurement value as the measurement result. Meter 2 is replaced, for example, at regular intervals. Also, meter 2 is replaced when a malfunction occurs in meter 2. In the following, in this specification, an example will be described in which meter 2 is a gas meter that measures gas usage.

The meter 2 is installed, for example, in a gas pipe. Gas to be measured by the meter 2 flows through the gas pipe. The gas is supplied to a consumer from a gas cylinder or a gas holder through the gas pipe. The gas to be measured by the meter 2 may be LP gas (liquefied petroleum gas) or city gas. The meter 2 measures the amount of gas used by measuring the flow rate of the gas flowing through the gas pipe. The type of the meter 2 is not particularly limited. The meter 2 is, for example, a 5-bit meter, an 8-bit meter, a U-bus meter, or a microcomputer meter. In the first embodiment, the meter 2 is a 5-bit meter.

Note that while the meter 2 will be described as an example of a measuring device, as long as the measuring device is related to resources or energy, the measuring device may be, for example, an on-off sensor provided in a gas shutoff device. The gas shutoff device is provided on a gas pipe. For example, when an earthquake is measured, the on-off sensor turns on and shuts off the gas pipe. In other words, it shuts off the flow of gas in the gas pipe. Note that when no earthquake is occurring, the on-off sensor is in the off state. When the on-off sensor is in the off state, gas flow is permitted. Gas flow indicates that gas is flowing through the gas pipe. The communication device 1 transmits information indicating that the on-off sensor is on to the base station B as a measurement result.

The communication device 1 transmits information indicating the measurement results of the meter 2 to the base station B. A communication device 1 is installed for each meter 2. The communication device 1 is also installed, for example, on a wall or gas pipe surrounding the meter 2. When installing the meter 2, a worker operates the communication device 1 to set it so that the communication device 1 can transmit the measurement results of the meter 2 to the base station B. Therefore, when installing the meter 2, a worker can cause the communication device 1 to start an operation mode related to communication between the communication device 1 and the base station B. As a result, the communication device 1 is set so that the measurement results of the meter 2 can be transmitted to the base station B.

The communication device 1 is connected to the meter 2 via a wire so that they can communicate with each other. The wire is, for example, an electric wire PL. The electric wire PL includes a signal line and a ground line. Note that the communication device 1 may also be connected to the meter 2 so that they can communicate with each other wirelessly.

The communication device 1 and the base station B are connected so as to be able to communicate wirelessly. Specifically, the communication device 1 and the base station B are connected to a wide area wireless network N2 such as an LTE (Long Term Evolution) network. Each of the multiple communication devices 1 and the base station B communicate wirelessly with each other via the wide area wireless network N2.

Continuing with the above, the communication device 1 will be described with reference to FIG. 1. As shown in FIG. 1, the communication device 1 includes a housing Ca and a battery 11. The communication device 1 further includes a control unit 10, a communication unit 40, and a connection unit 60.

The housing Ca houses the battery 11, the memory unit 12, the control unit 10, the communication unit 40, and the connection unit 60. The housing Ca is, for example, a hollow member. The housing Ca is made of a material that does not block magnetism, such as resin. The housing Ca is also, for example, waterproofed.

The storage unit 12 includes, for example, a semiconductor memory such as a ROM (Read Only Memory), a RAM (Random Access Memory), and a flash memory. The storage unit 12 stores various computer programs executed by the control unit 10. The storage unit 12 also stores programs indicating multiple operation modes. The storage unit 12 may further store, for example, a log of communication between the communication device 1 and the base station B.

The control unit 10 includes a processor, such as a CPU (Central Processing Unit) and an MPU (Micro Processing Unit), and a storage device. The processor controls each element of the communication device 1 by executing a computer program stored in the storage device. The control unit 10 also has a timer function and detects that a predetermined time has elapsed. The control unit 10 is also connected to a battery 11. The control unit 10 converts the power supply voltage supplied from the battery 11 into an internal power supply voltage and supplies the internal power supply voltage to the communication unit 40.

The communication unit 40 is connected to the wide area wireless network N2 and performs wireless communication via the wide area wireless network N2. The communication unit 40 is, for example, a wireless communication module that complies with the communication protocol of the wide area wireless network N2. The communication unit 40 communicates, for example, with one of a plurality of base stations B that emit radio waves in a first frequency band. The communication unit 40 also communicates, for example, with one of a plurality of base stations B that emit radio waves in a second frequency band.

The electric wire PL connected to the meter 2 is connected to the connection unit 60. That is, the connection unit 60 is wired to the meter 2 by the electric wire PL. The control unit 10 acquires information indicating the measurement results of the meter 2 via the electric wire PL and the connection unit 60. In the first embodiment, the type of the meter 2 that can be connected to the connection unit 60 is, for example, a 5-bit meter, a U-bus meter, or a microcomputer meter. In the first embodiment, the type of the meter 2 is a 5-bit meter. Therefore, the electric wire PL connected to the meter 2 is connected to the connection unit 60.

Continuing with the above, the process executed by the control unit 10 of the communication device 1 will be described with reference to FIG. 1. As shown in FIG. 1, the control unit 10 has a selection unit 13, a communication determination unit 14, a communication control unit 15, and a switching unit 16.

The communication control unit 15 controls the communication unit 40. For example, the communication control unit 15 controls the communication unit 40 so that the communication unit 40 receives notification information from each of the multiple base stations B at predetermined intervals. The notification information includes, for example, identification information of the telecommunications carrier and information indicating the frequency band. The notification information is, for example, continuously transmitted from the base station B to the communication device 1.

The communication determination unit 14 determines whether or not communication between the communication unit 40 and a first base station B, which is one of the multiple base stations B, is successful. For example, when the frequency band of the radio waves transmitted and received by the communication unit 40 is the first frequency band, the communication determination unit 14 determines whether or not communication between the base station BA and the communication unit 40 is successful. Also, for example, when the frequency band of the radio waves transmitted and received by the communication unit 40 is the second frequency band, the communication determination unit 14 determines whether or not communication between the base station BC and the communication unit 40 is successful.

The switching unit 16 switches the frequency band of the radio waves transmitted and received by the communication unit 40 to a second frequency band different from the first frequency band based on the determination result of the communication determination unit 14. For example, when the frequency band of the radio waves transmitted and received by the communication unit 40 is the first frequency band, the switching unit 16 switches the frequency band of the radio waves transmitted and received by the communication unit 40 from the first frequency band to the second frequency band.

Then, the communication control unit 15 controls the communication unit 40 so that the communication unit 40 communicates with one of the multiple base stations B that emit radio waves in the second frequency band. As a result, communication between the base station B and the communication unit 40 is possible, and it is possible to prevent the measurement results of the meter 2 from being unable to be transmitted to the server 3.

The control unit 10 of this embodiment measures the quality of radio waves based on the broadcast information. Specifically, the control unit 10 acquires and measures parameters indicating the quality of radio waves emitted from base station B based on the broadcast information. The quality of radio waves is represented, for example, by at least one of field strength and communication quality. The communication quality includes the received power of the RS (Reference Signal) (RSRP: Reference Signal Received Power) and the received quality of the RS (for example, RSRQ: Reference Signal Received Quality).

The selection unit 13 selects a base station B with which the communication unit 40 communicates. Specifically, based on a parameter indicating the quality of radio waves, the selection unit 13 selects one base station B with which the communication unit 40 communicates from among multiple base stations B that emit radio waves in the same frequency band.

For example, when the frequency band of radio waves used by the communication unit 40 is the first frequency band, the control unit 10 measures the quality of radio waves emitted from the base station BA. Then, based on a parameter indicating the quality of radio waves from the base station BA and a parameter indicating the quality of radio waves from the base station BB, the selection unit 13 selects one base station B from among the multiple base stations B with which the communication unit 40 will communicate.

For example, when the frequency band of the radio waves with which the communication unit 40 communicates is the second frequency band, the control unit 10 measures the quality of the radio waves emitted from the base station BC. Then, based on a parameter indicating the quality of the radio waves from the base station BC and a parameter indicating the quality of the radio waves from the base station BD, the selection unit 13 selects one base station B with which the communication unit 40 communicates from among the multiple base stations B.

Then, the communication control unit 15 controls the communication unit 40 so that the communication unit 40 communicates with the base station B selected by the selection unit 13. As a result, it is possible to communicate with the base station B with good radio wave quality.

In addition, if a parameter indicating the quality of radio waves from the base station BA selected by the selection unit 13 deteriorates, the selection unit 13 may select a base station B other than the base station BA that emits radio waves in the first frequency band.

Next, the processing of the control unit 10 of this embodiment will be described in detail with reference to Figs. 1 to 3. Fig. 2 is a diagram showing a communication device 1 and multiple base stations B. Fig. 3 is another diagram showing a communication device 1 and multiple base stations B. In Figs. 2 and 3, in order to facilitate understanding of the invention, an example in which the communication device 1 communicates with base station BA or base station BC will be described.

As shown in FIG. 2, for example, the communication unit 40 (see FIG. 1) of the communication device 1 is set to communicate with base station B that emits radio waves in the first frequency band. For example, the communication determination unit 14 determines whether or not communication between the communication unit 40 and base station B that emits radio waves in the first frequency band has been successful. For example, if communication between the communication unit 40 and base station B that emits radio waves in the first frequency band has been successful, the switching unit 16 does not switch the frequency band of the radio waves transmitted and received by the communication unit 40 to the second frequency band. In other words, the communication control unit 15 controls the communication unit 40 so that the communication unit 40 communicates with base station B that emits radio waves in the first frequency band.

When communicating with base station B that emits radio waves in the first frequency band, the control unit 10 acquires a parameter indicating the quality of the radio waves. For example, as shown in FIG. 1, the control unit 10 measures the radio waves emitted from base station BA, and acquires a parameter indicating the quality of the radio waves from base station BA. For example, as shown in FIG. 1, the control unit 10 measures the radio waves emitted from base station BB, and acquires a parameter indicating the quality of the radio waves from base station BB.

Then, for example, the selection unit 13 selects base station BA or base station BB based on a parameter indicating the quality of radio waves from base station BA and a parameter indicating the quality of radio waves from base station BB.

For example, if the selection unit 13 selects the base station BA, the communication control unit 15 controls the communication unit 40 so that the base station BA and the communication unit 40 communicate with each other. Also, as shown in Figures 1 and 2, the base station BA that receives a polling signal from the server 3 transmits page information to the communication device 1.

The communication unit 40 of the communication device 1 that receives the page information from the base station BA transmits a first message M1 to the base station BA. The first message M1 is a connection request ("RRC Connection Request" (Radio Resource Control Connection Request)).

If the base station BA can receive the first message M1, the base station BA transmits a second message M2 to the communication device 1 in response to the first message M1. The second message M2 is "RRC Connection Setup."

Having received the second message M2, the communication device 1 transmits a third message M3 to the base station BA. The third message M3 is an "RRC Connection Setup Complete." When the third message M3 is transmitted from the communication device 1 to the base station BA, the communication between the communication device 1 and the base station BA becomes successful.

In addition, base station B may transmit a change instruction to communication device 1 for the purpose of load balancing and reducing delays in communication speed. The change instruction indicates an instruction to change the frequency band of radio waves transmitted and received by communication unit 40. For example, the change instruction indicates an instruction to change the frequency band of radio waves transmitted and received by communication unit 40 from a first frequency band to a second frequency band.

Also, as shown in FIG. 3, there are cases where the base station BA cannot receive the first message M1. If the base station BA cannot receive the first message M1, the second message M2 is not transmitted from the base station BA to the communication device 1. In other words, communication has failed. Specifically, even though the communication device 1 receives radio waves from the base station BA, the base station BA and the communication device 1 cannot communicate with each other. In other words, communication between the communication device 1 and the base station BA has not been successful.

However, for example, in the communication control unit 15 of this embodiment, if communication between base station BA and the communication unit 40 is unsuccessful, the switching unit 16 switches the frequency band of the radio waves transmitted and received by the communication unit 40 to a second frequency band different from the first frequency band. In other words, as shown in FIG. 3, the communication control unit 15 controls the communication unit 40 so that the communication unit 40 communicates with a base station BC that emits radio waves in the second frequency band. Therefore, it is possible to prevent the communication unit 40 from attempting to communicate with a base station B with which it cannot communicate. As a result, it is possible to prevent the measurement results of the meter 2 from being unable to be transmitted to the server 3.

As shown in Figs. 1 and 3, the communication control unit 15 also executes fixed processing. The fixed processing indicates processing for prohibiting base station B, which communicates with the communication unit 40, from sending a change instruction. In other words, the frequency band of radio waves emitted by base station B with which communication is not possible due to a change instruction cannot be switched. Therefore, the communication unit 40 can communicate only with base station B with which communication is possible. As a result, it is possible to further prevent the measurement results of the meter 2 from being unable to be transmitted to the server 3.

For example, as shown in Figs. 1 and 3, based on a determination result indicating that communication between base station BA and communication unit 40 has not been successful, switching unit 16 switches the frequency band of radio waves transmitted and received by communication unit 40 to a second frequency band different from the first frequency band. Then, as shown in Fig. 1, communication control unit 15 controls communication unit 40 so that communication unit 40 communicates with base station BC or base station BD.

Specifically, when communicating with base station B that emits radio waves in the second frequency band, the control unit 10 acquires a parameter indicating the quality of the radio waves. For example, as shown in FIG. 1, the control unit 10 measures the radio waves emitted from base station BC, and acquires a parameter indicating the quality of the radio waves from base station BC. For example, as shown in FIG. 1, the control unit 10 measures the radio waves emitted from base station BD, and acquires a parameter indicating the quality of the radio waves from base station BD.

Then, for example, the selection unit 13 selects the base station BC or the base station BD based on a parameter indicating the quality of radio waves from the base station BC and a parameter indicating the quality of radio waves from the base station BD. For example, the communication control unit 15 transmits and receives the first message M1 to the third message M3 between the base station BC and the communication unit 40. Then, communication between the base station BC and the communication unit 40 is started.

Furthermore, the communication control unit 15 executes a fixing process. Therefore, for example, a change instruction is not transmitted from the base station BC. In other words, communication between the base station BC and the communication unit 40 is maintained. As a result, the communication unit 40 is not forced to change the frequency band of the radio waves it transmits and receives to the frequency band of the radio waves emitted by the base station B with which it cannot communicate, and the communication unit 40 can communicate with the base station B with which it can communicate and transmit the measurement results of the meter 2 to the server 3. Note that the fixing process may be performed at the same time that the selection unit 13 selects the base station B.

As shown in FIG. 1, the communication determination unit 14 of this embodiment determines whether communication between one of the multiple second base stations B and the communication unit 40 is successful. For example, when the communication determination unit 14 determines that communication between the base station BC and the communication unit 40 is not successful, the switching unit 16 switches the frequency band of the radio waves transmitted and received by the communication unit 40 to a frequency band different from the second frequency band. Then, the communication control unit 15 executes a fixing process to fix the frequency band of the radio waves transmitted and received by the communication unit 40 to a frequency band different from the second frequency band. In other words, if the base station B is changed to a base station B that emits radio waves of the second frequency band, and the base station B and the communication unit 40 cannot communicate with each other, the switching unit 16 changes the frequency band of the radio waves transmitted and received by the communication unit 40 to a frequency band different from the second frequency band. Then, the communication control unit 15 executes the fixing process. As a result, it is possible to suppress the inability to transmit the measurement results of the meter 2 to the server 3 while searching for a base station B that can communicate.

The communication control unit 15 also releases the fixed processing after a predetermined period of time has elapsed. After the predetermined period of time has elapsed, communication may become possible with a base station B that emits radio waves in a different frequency band from the base station B with which the communication unit 40 communicates in the frequency band of radio waves transmitted and received. The predetermined period is, for example, 10 days. Thus, the communication device 1 can accept an instruction to change the base station B and put the base station B in a state in which distributed processing is active. In other words, the communication device 1 accepts an instruction to change the base station B so as to achieve the objectives of load balancing of the base station B and reducing delays in communication speed. As a result, the measurement results of the meter 2 can be transmitted to the server 3 while the base station B is in a state in which distributed processing is active.

The communication control unit 15 repeats the execution of fixed processing and the release of fixed processing at regular intervals. Furthermore, even after a specified period has elapsed, there are cases where communication is not possible between base station B, which emits radio waves in a certain frequency band, and the communication unit 40. Therefore, by repeating the execution of fixed processing and the release of fixed processing, base station B's distributed processing is enabled, and a base station B that is capable of communication and the communication unit 40 can communicate. As a result, a base station B that is not capable of communication and the communication unit 40 can be prevented from attempting communication, while base station B's distributed processing is enabled.

If communication by the communication unit 40 is not successful in all frequency bands in which the communication unit 40 can transmit and receive radio waves, the communication control unit 15 does not execute fixed processing. Therefore, the communication control unit 15 causes the communication unit 40 to wait before attempting to communicate with base station B until base station B, which emits radio waves in any of the frequency bands, is in a state in which communication is possible. As a result, base station B and the communication unit 40 can communicate when communication is possible.

Next, the process executed by the control unit 10 will be described with reference to Figs. 4 and 5. Fig. 4 shows a flowchart of the process executed by the control unit 10. As shown in Fig. 4, the process executed by the control unit 10 includes steps S11 to S17.

In step S11, the communication control unit 15 controls the communication unit 40 so that the communication unit 40 communicates with base station B that emits radio waves in the first frequency band. The process proceeds to step S12.

In step S12, the communication determination unit 14 determines whether or not communication between the base station B, which emits radio waves in the first frequency band, and the communication unit 40 has been successful. If communication between the base station B and the communication unit 40 has not been successful (No in step S12), the process proceeds to step S16. If communication between the base station B and the communication unit 40 has been successful (Yes in step S12), the process ends.

If the answer is Yes in step S12, in step S13, the control unit 10 determines whether the quality of the radio waves emitted by base station B is good. If the quality of the radio waves emitted by base station B is not good (No in step S13), the process proceeds to step S16. If the quality of the radio waves emitted by base station B is good (Yes in step S12), the process proceeds to step S14.

In step S14, the communication control unit 15 controls the communication unit 40 so that the communication unit 40 continues communication with base station B. The process ends.

If the answer is No in step S12, in step S15, the communication control unit 15 executes a fixing process. The fixing process will be described later with reference to FIG. 5. The process returns to step S11.

If the answer is No in step S13, in step S16, the selection unit 13 selects one base station B with which the communication unit 40 will communicate from among multiple base stations B that emit radio waves in the same frequency band. The process proceeds to step S17.

In step S17, the communication control unit 15 controls the communication unit 40 so that the communication unit 40 communicates with base station B. The process ends.

Next, the fixing process executed by the control unit 10 will be described in detail with reference to FIG. 5. FIG. 5 is a flowchart showing the fixing process executed by the control unit 10. As shown in FIG. 5, the fixing process executed by the control unit 10 includes steps S161 to S167.

In step S161, the switching unit 16 switches the frequency band of the radio waves transmitted and received by the communication unit 40 to a second frequency band different from the first frequency band based on the determination result of the communication determination unit 14. Then, the communication control unit 15 executes a fixing process. The process returns to step S162.

In step S162, the communication control unit 15 determines whether communication between the base station B, which emits radio waves in the second frequency band, and the communication unit 40 has been successful. If communication between the base station B and the communication unit 40 has not been successful (No in step S162), the process proceeds to step S166. If communication between the base station B and the communication unit 40 has been successful (Yes in step S162), the process proceeds to step S163.

If the answer is Yes in step S162, in step S163, the communication control unit 15 determines whether or not a predetermined period of time has elapsed since the fixed process was executed. If the predetermined period of time has not elapsed since the fixed process was executed (No in step S163), the process repeats step S163. If the predetermined period of time has elapsed since the fixed process was executed (Yes in step S163), the process proceeds to step S164.

If the answer is Yes in step S163, in step S164, the communication control unit 15 releases the fixed processing. The process returns to the flowchart shown in FIG. 4.

In addition, after canceling the fixed processing in step S164, the communication control unit 15 may further determine whether or not a predetermined period of time has elapsed since the fixed processing was canceled. If the predetermined period of time has elapsed since the fixed processing was canceled, the process may return to step S161. In other words, the communication control unit 15 repeats the execution of the fixed processing and the cancellation of the fixed processing at regular intervals.

If the answer is No in step S162, then in step S166 the control unit 10 determines whether or not communication by the communication unit 40 has failed in all frequency bands in which the communication unit 40 can transmit and receive radio waves. If communication by the communication unit 40 has failed in all frequency bands (Yes in step S166), the process proceeds to step S168. In other words, if communication by the communication unit 40 is unsuccessful in all frequency bands in which the communication unit 40 can transmit and receive radio waves, the communication control unit 15 does not execute fixed processing and the process proceeds to step S168. If communication by the communication unit 40 has not failed in all frequency bands (No in step S166), the process proceeds to step S167.

If the answer is No in step S166, the switching unit 16 switches the frequency band of the radio waves transmitted and received by the communication unit 40 to a frequency band different from the second frequency band based on the determination result of the control unit 10. Then, the communication control unit 15 executes a fixing process. The process returns to step S162.

If the answer is Yes in step S166, in step S168, the communication control unit 15 releases the fixed processing. The process returns to the flowchart shown in FIG. 4.

The above describes an embodiment of the present invention with reference to the drawings. However, the present invention is not limited to the above embodiment, and can be implemented in various forms without departing from the gist of the present invention. The drawings are mainly schematic illustrations of each component for ease of understanding, and the number, spacing, etc. of each component shown in the drawings may differ from the actual number due to the convenience of creating the drawings. Furthermore, each component shown in the above embodiment is merely an example, and is not particularly limited, and various modifications are possible without substantially departing from the configuration of the present invention.

The present invention provides a communication device and has industrial applicability.

1: Communication device 2: Meter 10: Control unit 13: Selection unit 14: Communication determination unit 15: Communication control unit 16: Switching unit 40: Communication unit B: Base station BA: Base station BB: Base station BC: Base station BD: Base station

Claims (6)

a communication unit that communicates with one of a plurality of first base stations that emit radio waves in a first frequency band;
a communication determination unit that determines whether communication between one of the plurality of first base stations and the communication unit has been successful;
a switching unit that switches a frequency band of radio waves transmitted and received by the communication unit to a second frequency band different from the first frequency band based on a determination result of the communication determination unit;
a communication control unit that controls the communication unit so that the communication unit communicates with one of a plurality of second base stations that emit radio waves in the second frequency band;
When the communication determination unit determines that communication between one of the plurality of first base stations and the communication unit is not successful, the switching unit switches a frequency band of radio waves transmitted and received by the communication unit from the first frequency band to the second frequency band,
the communication control unit executes a fixing process of fixing a frequency band of radio waves transmitted and received by the communication unit to the second frequency band;
the fixing process indicates a process of prohibiting a base station communicating with the communication unit from transmitting a change instruction,
The change instruction indicates an instruction to change a frequency band of radio waves transmitted and received by the communication unit. A selection unit that selects one of the plurality of second base stations based on a parameter indicating a quality of the radio wave,
The communication device according to claim 1 , wherein the communication control unit controls the communication unit so that the communication unit communicates with the second base station selected by the selection unit. the communication determination unit determines whether communication between one of the plurality of second base stations and the communication unit has been successful;
When the communication determination unit determines that communication between one of the plurality of second base stations and the communication unit is not successful, the switching unit switches the frequency band of the radio waves transmitted and received by the communication unit to a frequency band different from the second frequency band,
The communication device according to claim 1 , wherein the communication control unit executes a fixing process for fixing a frequency band of radio waves transmitted and received by the communication unit to the different frequency band. The communication device according to claim 2 or 3, wherein the communication control unit cancels the fixing process after a predetermined period of time has elapsed. The communication device according to any one of claims 1 to 4, wherein the communication control unit repeats execution of the fixed process and cancellation of the fixed process at regular intervals. The communication device according to any one of claims 1 to 5, wherein if communication by the communication unit is not successful in all frequency bands in which the communication unit can transmit and receive radio waves, the communication control unit does not execute the fixed processing.

Images