JP7650165B2 - Base station and control method - Google Patents

Description

This disclosure relates to a base station and a control method.

Unlicensed bands are sometimes used for communication between wireless communication devices (e.g., between a base station and a terminal). Because unlicensed bands are used by a variety of wireless communication systems, interference due to various factors can occur, and this interference can degrade communication characteristics (e.g., throughput).

For example, Patent Document 1 describes a wireless communication system that increases the overall throughput of multiple base stations by controlling the channel allocation of channels acquired by the base stations by a central station.

JP 2013-81089 A

However, there is room for further study on methods to improve communication characteristics by performing control that takes interference into account in an environment where various wireless communication systems are used.

Non-limiting examples of the present disclosure contribute to providing a base station and a control method that can improve communication characteristics by performing control that takes interference into account.

A base station according to an embodiment of the present disclosure is a base station that supports a first wireless system and belongs to a first network, and includes a measurement unit that measures a first amount of interference based on a received signal received at a specific measurement time, an estimation unit that estimates a second amount of interference based on a received signal determined to have been transmitted by a first wireless device that supports the first wireless system and belongs to the first network, a correction unit that corrects the second amount of interference based on a communication success rate of the first wireless device, and a determination unit that determines a third amount of interference based on a signal transmitted by a second wireless device that does not belong to the first network, from the first amount of interference and the corrected second amount of interference.

A control method according to one embodiment of the present disclosure includes: a base station supporting a first wireless system and belonging to a first network measures a first amount of interference based on a received signal received at a specific measurement time; estimating a second amount of interference based on a received signal determined to have been transmitted by a first wireless device supporting the first wireless system and belonging to the first network; correcting the second amount of interference based on a communication success rate of the first wireless device; and determining a third amount of interference based on a signal transmitted by a second wireless device not belonging to the first network from the first amount of interference and the corrected second amount of interference.

These comprehensive or specific aspects may be realized as a system, device, method, integrated circuit, computer program, or recording medium, or as any combination of a system, device, method, integrated circuit, computer program, and recording medium.

According to one embodiment of the present disclosure, communication characteristics can be improved by performing control that takes interference into account.

Further advantages and benefits of an embodiment of the present disclosure will become apparent from the specification and drawings. Such advantages and/or benefits may be provided by some of the embodiments and features described in the specification and drawings, respectively, but not necessarily all of them need be provided to obtain one or more identical features.

FIG. 1 is a diagram showing an overview of a wireless system including an LPWA. FIG. 1 is a block diagram showing a configuration example of a base station according to an embodiment; FIG. 13 is a diagram showing an example of a process for classifying interference into interference within management and interference outside management. A diagram showing an example of an error in interference classification. FIG. 4B illustrates an example of channel allocation in response to the misclassification shown in FIG. 4A. A diagram showing an example of a communication success rate A flowchart showing a first example of a processing flow of a base station in an embodiment. A flowchart showing a second example of a processing flow of a base station in an embodiment. A flowchart showing a third example of a processing flow of a base station in an embodiment. A flowchart showing a fourth example of a processing flow of a base station in an embodiment. A flowchart showing a fifth example of a processing flow of a base station in an embodiment. A flowchart showing a sixth example of a processing flow of a base station in an embodiment. A flowchart showing a seventh example of a processing flow of a base station in an embodiment. A flowchart showing an eighth example of the flow of processing by a base station in an embodiment.

A preferred embodiment of the present disclosure will be described in detail below with reference to the attached drawings. In this specification and drawings, components having substantially the same functions are designated by the same reference numerals to avoid redundant description.

(One embodiment)
In the Internet of Things (IoT) and/or Machine to Machine (M2M), the use of a wireless communication technology called Low Power Wide Area (LPWA), which enables communication over a wide area with low power consumption, is being considered.

Operation of LPWA in unlicensed bands (e.g., 920 MHz band) is being considered. There are multiple methods (standards) for LPWA. For example, LPWA communication methods include a first communication method that uses a spread spectrum method for communication, and a second communication method that does not use a spread spectrum method. The first communication method includes, for example, a communication method called "LoRa." The second communication method includes, for example, a communication method called "Wi-SUN (Wireless Smart Utility Network)."

In the following, a communication method called "LoRa" (hereinafter referred to as "LoRa method") is given as an example of the first communication method, and a communication method called "Wi-SUN" (hereinafter referred to as "Wi-SUN method") is given as an example of the second communication method. However, the present disclosure is not limited to the LoRa method and the Wi-SUN method.

Furthermore, below, a terminal that operates based on the LoRa method (supports the LoRa method) may be described as a "LoRa terminal", and a terminal that operates based on the Wi-SUN method (supports the Wi-SUN method) may be described as a "Wi-SUN terminal". Furthermore, "LoRa terminals" and "Wi-SUN terminals" may be described as LPWA terminals without distinction. Furthermore, below, a signal transmitted and received based on the LoRa method is described as a "LoRa signal", and a signal transmitted and received based on the Wi-SUN method is described as a "Wi-SUN signal".

LPWA terminals are not limited to terminals owned by users, but are installed in various devices. For example, LPWA terminals are installed in home appliances such as televisions, air conditioners, washing machines, and refrigerators, as well as in mobile transportation such as vehicles.

In addition to LPWA, unlicensed bands are used by a variety of systems, including Wi-Fi (registered trademark) and RFID (Radio Frequency IDentifier).

In the following, an example will be described in which the wireless system according to the present embodiment is an LPWA system. The present disclosure is not limited to this, and may be applied to wireless systems other than LPWA systems.

Figure 1 shows an overview of a wireless system including an LPWA.

Figure 1 shows group #1, group #2, and group #3. Each group includes multiple devices.

Both groups #1 and #2 are LPWA systems. However, network #1 (NW#1) to which each device in group #1 belongs is different from network #2 (NW#2) to which each device in group #2 belongs. For example, NW#1 and NW#2 are the same LPWA system, but are networks operated by different operators. The LPWA system in group #2 is a wireless system in a network not managed by group #1 (unmanaged network).

Group #1 includes devices that belong to NW #1 and are connected to NW #1 via a wired or wireless connection. For example, group #1 includes base station #1, Wi-SUN terminal #1, LoRa terminal #1, and LoRa terminal #2. Group #1 also includes control device #1 that centrally controls GWs, etc. via NW #1. The control device may be a server, a control server, etc.

Base station #1 may have a gateway (GW) function and a radio wave monitoring function. For example, the GW function of base station #1 may support both the Wi-SUN and LoRa systems. Wi-SUN terminal #1, LoRa terminal #1, and LoRa terminal #2 may be wirelessly connected to base station #1 and transmit and receive signals.

Group #2 includes devices that belong to NW #2 and are connected to NW #2 via wired or wireless connections. For example, group #2 includes base station #2, Wi-SUN terminal #2, LoRa terminal #3, and LoRa terminal #4. Group #2 also includes control device #2 that centrally controls GWs and the like via NW #2.

Base station #2 may have a GW function and a radio wave monitoring function. For example, the GW function of base station #2 may support both the Wi-SUN and LoRa systems. Wi-SUN terminal #2, LoRa terminal #3, and LoRa terminal #4 may be wirelessly connected to base station #2 to transmit and receive signals.

Note that the number of devices in group #1 and group #2 in FIG. 1 is an example, and the present disclosure is not limited thereto. For example, the number of base stations included in group #1 and group #2 in FIG. 1 may be two or more. The number of LPWA terminals included in group #1 and group #2 in FIG. 1 may be four or more, or two or less. In addition, other devices may be connected to the network of each group.

Group #1 may also include a relay station that relays wireless communication between base station #1 and one of the terminals. Group #2 may also include a similar relay station.

Group #3 is a wireless system different from the wireless system (LPWA system) of group #1. The wireless system of group #3 is a wireless system of an unmanaged network that is not managed by group #1. The wireless system of group #3 is, for example, an RFID system. Group #3 includes an RFID reader/writer and an RFID tag. The wireless system of group #3 may include an LTE (Long Term Evolution) system, a radar system, etc.

Note that the network configuration and/or device configuration shown in FIG. 1 is an example, and the present disclosure is not limited thereto.

For example, FIG. 1 shows an example in which the LoRa terminal and the Wi-SUN terminal are separate terminals, but the terminal may be capable of operating based on both the LoRa system and the Wi-SUN system.

In the above, base station #1 and base station #2 have an example in which they have a GW that supports both the Wi-SUN system and the LoRa system, but the GW that supports the Wi-SUN system and the GW that supports the LoRa system may be separate devices. Also, the device that performs radio wave monitoring may be a device separate from the base station.

Also, for example, two or more of the Wi-SUN gateway, LoRa gateway, radio wave monitoring device, and control device may be integrated.

Each network shown in FIG. 1 may include devices other than those shown in FIG. 1. In that case, the other devices may have some or all of the functions of the devices shown in FIG. 1. For example, if a relay station is provided between a base station and a Wi-SUN terminal and/or a LoRa terminal, the relay station may have the functions of a radio wave monitoring device. The relay station may also have the functions of a Wi-SUN gateway and/or a LoRa gateway and the functions of a radio wave monitoring device. Alternatively, the relay station may have the functions of a radio wave monitoring device, but not the functions of a Wi-SUN gateway and/or a LoRa gateway.

Each wireless device in groups #1 to #3 uses a common system band (e.g., an unlicensed band). Therefore, each wireless device in groups #1 to #3 is subject to interference from the other wireless devices. We will explain this using the example of interference experienced by a wireless device in group #1.

For example, a signal transmitted or received by a wireless device (e.g., LoRa terminal #2) included in group #1 causes interference in another wireless device (e.g., LoRa terminal #1) included in group #1. Hereinafter, interference received by a wireless device belonging to NW #1 from another wireless device belonging to NW #1 may be described as "interference within management." For example, interference within management corresponds to interference received by a wireless device that supports communication in an LPWA system and belongs to NW #1 from another wireless device that supports communication in the LPWA system and belongs to NW #1.

In addition, a terminal (e.g., LoRa terminal #2) that belongs to the same network as a certain base station (e.g., base station #1) and a certain terminal (e.g., LoRa terminal #1) may be described as an "in-management terminal" with respect to the certain base station and the certain terminal. An in-management terminal may be a terminal that may transmit a signal that causes in-management interference. In addition, a LoRa terminal and a Wi-SUN terminal that are in-management terminals may be described as an "in-management LoRa terminal" and an "in-management Wi-SUN terminal", respectively.

Furthermore, for example, a signal transmitted or received by a wireless device (e.g., LoRa terminal #3 and/or an RFID reader/writer) included in group #2 and/or group #3 causes interference in a wireless device (e.g., LoRa terminal #1) included in group #1. Hereinafter, interference received by a wireless device belonging to NW #1 from a wireless device not belonging to NW #1 may be described as "unmanaged interference." For example, unmanaged interference corresponds to interference received by a wireless device that supports communication in an LPWA system and belongs to NW #1 from a wireless device not belonging to NW #1.

In addition, a terminal (e.g., LoRa terminal #3) that belongs to a different network from a certain base station (e.g., base station #1) and a certain terminal (e.g., LoRa terminal #1) may be described as an "unmanaged terminal" with respect to the certain base station and the certain terminal. An unmanaged terminal may be a terminal that may transmit a signal that causes unmanaged interference. In addition, a LoRa terminal and a Wi-SUN terminal that are unmanaged terminals may be described as an "unmanaged LoRa terminal" and an "unmanaged Wi-SUN terminal", respectively.

Uncontrolled interference may be further classified based on the cause of the interference.

For example, a signal transmitted or received by a wireless device (e.g., LoRa terminal #3) included in group #2 causes interference in a wireless device (e.g., LoRa terminal #1) included in group #1. In the following, interference received by a wireless device belonging to NW #1 from a wireless device belonging to NW #2 may be described as "radio interference" among "unmanaged interference". For example, "radio interference" corresponds to interference received by a wireless device belonging to NW #1, which supports communication in an LPWA system, from a wireless device belonging to NW #2, which supports communication in an LPWA system and is different from NW #1.

Furthermore, for example, a signal transmitted or received by a wireless device (e.g., an RFID reader/writer) included in group #3 causes interference in a wireless device (e.g., LoRa terminal #1) included in group #1. In the following, interference received by a wireless device that supports communication in the LPWA system and belongs to NW #1 from a wireless device that supports a wireless system different from the LPWA system may be described as "ambient noise" under "unmanaged interference."

As shown in FIG. 1 as an example, an LPWA system uses a common system band with a wireless system different from the LPWA system and/or with the same LPWA system that belongs to a different network. Therefore, it is desirable for the LPWA system to detect (monitor) interference and use the detected results to improve the efficiency (e.g., frequency utilization efficiency) and/or communication quality (communication characteristics) of the LPWA system.

In a wireless system including LPWA, a base station assigns channels to terminals (managed terminals) under the base station, and the managed terminals transmit signals on the assigned channels using the LoRa and/or Wi-SUN systems. In the channel assigned to the managed terminal, other managed terminals and/or unmanaged terminals transmit signals, which may cause interference and degrade communication characteristics.

For example, it is being considered that a base station could classify the interference that occurs in each channel and assign channels to managed terminals based on the classification results, thereby making appropriate channel assignments and suppressing degradation of communication characteristics.

However, for example, if an interference component that is within-management interference is classified as unmanaged interference, there is a risk that an appropriate channel cannot be assigned to an within-management terminal.

In a non-limiting embodiment of the present disclosure, a base station and a control method are described that can achieve appropriate channel allocation to managed terminals and improve communication characteristics by correcting (compensating) for errors in interference classification.

The wireless communication system according to this embodiment includes the base station 100 shown in FIG. 2 and a terminal subordinate to the base station 100. The base station 100 and the terminal are included in, for example, an LPWA wireless communication system. For example, the base station 100 supports both the LoRa system and the Wi-SUN system.

<Base station configuration>
2 is a block diagram showing a configuration example of a base station 100 according to this embodiment. The base station 100 includes a receiving unit 101, a communication quality measuring unit 102, a preamble detecting unit 103, an interference classifying unit 104, a correcting unit 105, a demodulating/decoding unit 106, an allocation control unit 107, a control signal generating unit 108, an encoding/modulating unit 109, and a transmitting unit 110. For example, some or all of the communication quality measuring unit 102, the preamble detecting unit 103, the interference classifying unit 104, the correcting unit 105, the demodulating/decoding unit 106, the allocation control unit 107, the control signal generating unit 108, and the encoding/modulating unit 109 may be collectively referred to as a "control unit."

The receiving unit 101 receives a signal transmitted by the terminal and performs a predetermined receiving process on the received signal. For example, the predetermined receiving process includes a frequency conversion process (down-conversion) based on the frequency of the channel assigned to the terminal. Information on the frequency of the channel assigned to the terminal may be obtained, for example, from the allocation control unit 107.

The receiving unit 101 also receives signals on each available channel (e.g., each channel included in the unlicensed band) for interference measurement (radio wave monitoring). The receiving unit 101 then performs a predetermined reception process on the received signal. The predetermined reception process includes, for example, a frequency conversion process based on the frequency of each channel.

The receiving unit 101 outputs the received signal that has undergone a predetermined receiving process to the communication quality measuring unit 102, the preamble detecting unit 103, and the demodulating/decoding unit 106.

The demodulation/decoding unit 106 performs demodulation and decoding of the received signal to generate received data. For example, if the received signal is a LoRa signal, the demodulation/decoding unit 106 performs despreading of the LoRa signal. The demodulation/decoding unit 106 outputs the received data to the allocation control unit 107. Note that the received data may include an identifier that identifies a terminal that belongs to the same NW (Network) as the base station 100.

The communication quality measurement unit 102 generates communication quality information based on the received signal acquired from the receiving unit 101. The communication quality information may include, for example, the quality of the received signal (for example, Received Signal Strength Indicator (RSSI)). The communication quality information may also include an error detection result of the received signal. The communication quality measurement unit 102 outputs the communication quality information to the allocation control unit 107. Note that the result of error detection of the received signal may be obtained by demodulation processing or decoding processing in the demodulation/decoding unit 106.

The preamble detection unit 103 detects whether or not a preamble is included in the received signal acquired from the receiving unit 101. If a preamble is included, the preamble detection unit 103 determines the type of preamble included in the received signal.

For example, the preamble detection unit 103 calculates the correlation between a preamble used in the LoRa system and the received signal. If the calculated correlation results in a peak equal to or greater than a predetermined value, the preamble detection unit 103 determines that the received signal contains a preamble used in the LoRa system. If the received signal contains a preamble used in the LoRa system, it is determined that the received signal is a LoRa signal and that the sender of the received signal is a LoRa terminal.

As in the example of the LoRa system, the preamble detection unit 103 calculates the correlation between the preamble used in the Wi-SUN system and the received signal. If a peak equal to or greater than a predetermined value occurs in the calculated correlation, the preamble detection unit 103 determines that the received signal contains a preamble used in the Wi-SUN system. If the received signal contains a preamble used in the Wi-SUN system, it is determined that the received signal is a Wi-SUN signal and that the sender of the received signal is a Wi-SUN terminal.

Note that the preamble detection unit 103 detects the preamble regardless of whether the source of the received signal is included in the network to which the base station 100 belongs. In other words, the preamble detection unit 103 may determine the type of preamble included in a signal transmitted by a LoRa terminal and a Wi-SUN terminal that are not included in the network to which the base station 100 belongs.

In addition, if no peak equal to or greater than a predetermined value occurs in either the correlation result between the preamble used in the LoRa system and the received signal or the correlation result between the preamble used in the Wi-SUN system and the received signal, the preamble detection unit 103 determines that the sender of the received signal is neither a LoRa terminal nor a Wi-SUN terminal.

The preamble detection unit 103 outputs information indicating whether or not a preamble is included in the received signal, and, if a preamble is included in the received signal, information indicating the type of the preamble, to the interference classification unit 104. In addition, the preamble detection unit 103 outputs the received signal acquired from the receiving unit 101 to the interference classification unit 104.

The interference classification unit 104 classifies, for example, the interference in each channel. For example, the interference classification unit 104 performs classification by monitoring the received signal for a predetermined time in one channel. For example, the interference classification unit 104 may determine the difference in the source of the received signal within the predetermined time. The interference classification unit 104 calculates the ratio of the time of the received signal for each source to the predetermined time, and classifies the interference in each channel. For example, the interference classification unit 104 may classify the source of the signal that causes dominant interference in the interference in each channel. Here, dominant interference in each channel may correspond to, for example, a proportion of the time that occupies a predetermined percentage or more of the predetermined time as a result of monitoring the received signal for a predetermined time.

The interference classification unit 104 outputs the interference classification results for each channel to the correction unit 105.

The correction unit 105 corrects the interference classification result for each channel. For example, the correction unit 105 corrects the interference classification result based on information on the success or failure of communication from the source of the signal that caused the interference. Alternatively, the correction unit 105 performs correction based on past interference classification results. The correction unit 105 may perform correction based on information on the received signal obtained from the allocation control unit 107 (for example, packet information such as data volume and/or reception interval). The correction method will be described later. The correction unit 105 outputs the corrected interference classification result to the allocation control unit 107.

The allocation control unit 107 determines the channel to be assigned to the terminal based on the communication quality information (e.g., information indicating the received power such as RSSI) acquired from the communication quality measurement unit 102. The allocation control unit 107 may determine the channel to be assigned to the terminal based on the communication quality information and the interference classification result acquired from the correction unit 105.

The allocation control unit 107 outputs information about the channels allocated to the terminal (channel allocation information) to the control signal generation unit 108.

The allocation control unit 107 also controls data communication with the terminal. For example, the received data acquired from the demodulation/decoding unit 106 may be output to a higher-level station (not shown) or to another device in the network (for example, a control device (see FIG. 1)). The allocation control unit 107 also outputs transmission data addressed to the terminal acquired from a higher-level station or another device in the network to the encoding/modulation unit 109. The transmission data addressed to the terminal may include an identifier indicating the destination.

The control signal generating unit 108 generates a control signal addressed to the terminal based on the channel allocation information acquired from the allocation control unit 107. The control signal generating unit 108 outputs the control signal that has been subjected to predetermined signal processing (e.g., encoding processing and modulation processing) to the transmitting unit 110.

The coding/modulation unit 109 performs coding and modulation processing on the transmission data acquired from the allocation control unit 107 to generate a transmission signal. The coding/modulation unit 109 outputs the transmission signal to the transmission unit 110. Note that if the terminal to which the transmission signal is to be sent is a LoRa terminal, the modulation processing may include spectrum spreading processing used in the LoRa system.

The transmitting unit 110 performs a predetermined transmission process on the transmission signal acquired from the encoding/modulation unit 109. For example, the predetermined transmission process includes a frequency conversion process (up-conversion) based on the frequency of the channel assigned to the terminal. Information on the frequency of the channel assigned to the terminal may be acquired, for example, from the allocation control unit 107.

The transmitting unit 110 also performs a predetermined transmission process on the control signal acquired from the control signal generating unit 108. For example, the predetermined transmission process includes a frequency conversion process (up-conversion) based on the frequency of the channel for transmitting the control signal to the terminal. The channel for transmitting the control signal to the terminal may be, for example, a predetermined channel, or may be a channel currently being used for communication with the terminal.

In the above, an example has been described in which the configuration shown in FIG. 2 is included in one base station 100. The present disclosure is not limited to this. For example, any one of two or more devices may include each of the configurations shown in FIG. 2.

In addition, in the above description, an example has been given in which the base station 100 shown in FIG. 2 is included in an LPWA system, but the base station 100 of the present disclosure may support a communication method different from the LPWA communication method. For example, the base station 100 may support the Wi-Fi communication method instead of the LPWA communication method, or may support both the LPWA and Wi-Fi communication methods.

<Classification process example>
Next, a description will be given of an example of the classification process in the interference classification unit 104. A classification process for classifying a signal (interference) received in the receiving unit 101 into within-management interference and outside-management interference will be described.

<Example of classification process of interference within control and interference outside control>
Fig. 3 is a diagram showing an example of classification processing of in-management interference and out-of-management interference. The horizontal axis of Fig. 3 indicates the time axis. Fig. 3 shows the signal level of a received signal in a predetermined monitoring section, the detection result of interference with the received signal, the detection result of the terminal identifier (terminal ID), and the judgment result.

The detection result of interference with the received signal corresponds to, for example, the detection result by preamble detection. The LoRa signal contained in the received signal is determined based on this result.

When the terminal identifier (terminal ID) detection result shows that an identifier can be obtained by demodulation/decoding processing of the received signal, the terminal ID indicates "OK". When the terminal ID indicates "OK", it is determined that the network to which the sender of the received signal belongs is the same network as base station 100. In other words, as shown in the determination result, it is determined that the received signal corresponds to intra-management interference.

When the terminal identifier (terminal ID) detection result indicates that the identifier cannot be obtained by demodulation/decoding processing of the received signal, the terminal ID indicates "NG." When the terminal ID indicates "NG," it is determined that the network to which the sender of the received signal belongs is a network different from base station 100. In other words, as indicated by the determination result, it is determined that the received signal corresponds to unmanaged interference.

The above classification process classifies the received signal as corresponding to either managed interference or unmanaged interference.

For example, in the classification described above, if the demodulation and decoding of a received signal is performed without error and the terminal ID cannot be detected, the received signal is determined to correspond to non-management interference, not to within-management interference. As a result, an interference component that is actually within-management interference may be determined to be non-management interference, and a correct classification result may not be obtained.

Figure 4A is a diagram showing an example in which an error occurs in interference classification. Figure 4B is a diagram showing an example of channel allocation according to the classification error shown in Figure 4A. The horizontal axis of Figures 4A and 4B indicates frequency (channel), and the vertical axis indicates transmission probability (or channel occupancy rate).

Figure 4A shows an example of interference measured and classified in four channels, ch#1 to ch#4. For example, ch#3 and ch#4 are channels in which there is an unmanaged interference component and no in-management interference component. ch#1 and ch#2 are channels in which there is an in-management interference component and no unmanaged interference component. However, some of the in-management interference components of ch#1 and ch#2 are in-management interference (in-management interference that results in communication failure) caused by a received signal that was unsuccessfully received by base station 100.

In ch#1 and ch#2 shown in FIG. 4A, the base station 100 judges that "interference within management that causes communication to be NG" is interference outside management. In this case, the base station 100 judges that there is more interference outside management in ch#1 and ch#2 than there actually is.

Figure 4B shows an example of channel allocation to an in-management terminal after determining that the "in-management interference that does not allow communication" in Figure 4A is out-of-management interference.

In ch#1 and ch#2 in Figure 4B, it is determined that there is more non-managed interference than actually exists, so some of the managed terminals that would have been assigned to ch#1 and ch#2 are assigned to ch#3 and ch#4. As a result, the transmission probability is no longer balanced between the channels, resulting in inappropriate channel assignment.

In this embodiment, the correction unit 105 of the base station 100, for example, improves the accuracy of the interference classification results by correcting the difference that occurs when a component of managed interference, such as that illustrated in FIG. 4A, is determined to be unmanaged interference.

The method of classifying interference into within-management interference and unmanaged interference is not particularly limited, but for example, a channel occupancy rate may be used to classify interference into within-management interference and unmanaged interference in a certain channel. Hereinafter, a channel occupancy rate corresponding to within-management interference may be described as an "in-management channel occupancy rate," and a channel occupancy rate corresponding to unmanaged interference may be described as an "unmanaged channel occupancy rate." Although the channel occupancy rate represents the amount of interference, the present disclosure is not limited thereto. The amount of interference may be represented by other parameters.

Below, as an example, interference classification in channel #m to which N managed terminals, managed terminal #1 to managed terminal #N, are assigned will be described. Note that channel #m represents, for example, a channel whose identifier for identifying the channel is m, where m is an integer equal to or greater than 0. Also, managed terminal #i (i is an integer between 1 and N) represents a managed terminal whose identifier for identifying the managed terminal is i, where N is an integer equal to or greater than 1.

For example, the out-of-control channel occupancy rate COR _out in a certain channel #m is determined using the total channel occupancy rate COR _total in a certain channel #m and the in-control channel occupancy rate COR _in, as shown in equation (1).

The in-management channel occupancy rate COR _in is represented by the sum of the channel occupancy rates of the in-management terminals assigned to the channel #m. The channel occupancy rate cor(i) of the in-management terminal #i may be represented by, for example, formula (2).
cor(i) = (number of successfully communicated packets) × (time length of packet) / observation time (2)

The "number of successful communication packets" in formula (2) indicates the number of packets transmitted by managed terminal #i and successfully received by base station 100, and the "duration of packets" indicates the duration of packets successfully received by base station 100. cor(i) shown in formula (2) is an example of the channel occupancy rate of managed terminal #i calculated by base station 100.

Since cor(i) in equation (2) is a value based on the number of packets that the base station 100 successfully receives, it does not take into account the number of packets that the managed terminal #i transmitted and the base station 100 failed to receive. In this case, as shown in FIG. 4A, the channel occupancy rate based on packets that the managed terminal #i transmitted and the base station 100 failed to receive is classified as an unmanaged channel occupancy rate, which is not an appropriate classification.

Therefore, in this embodiment, a method for appropriately classifying interference into within-management interference and outside-management interference by correcting the channel occupancy rate based on packets transmitted by an within-management terminal and failed to be received by the base station 100 is described.

For example, the first correction method is a method that uses information regarding the success or failure of packet communication. The information regarding the success or failure of packet communication is, for example, the communication success rate. The communication success rate of managed terminal #i indicates the ratio between the total number of packets transmitted by managed terminal #i within a certain period of time and the number of packets transmitted by managed terminal #i and successfully received by base station 100.

The communication success rate of managed terminal #i may be estimated, for example, based on the channel occupancy rate of managed terminal #i and the strength of the signal transmitted by managed terminal #i and received by base station 100 (e.g., received signal strength indicator (RSSI)). For example, the communication success rate may be represented by a variable with the channel occupancy rate and RSSI as parameters.

Figure 5 is a diagram showing an example of a communication success rate. The horizontal axis of Figure 5 indicates the channel occupancy rate, and the vertical axis indicates the communication success rate. Figure 5 shows the communication success rate versus the channel occupancy rate for each of three cases where the RSSI is x [dB], y [dB], and z [dB]. Note that the channel occupancy rate on the horizontal axis of Figure 5 corresponds to, for example, the channel occupancy rate expressed by equation (2) (the channel occupancy rate before correction).

For example, if the RSSI is x [dB] and the channel occupancy rate is 0.6, the communication success rate is 0.2.

For example, if the communication success rate of managed terminal #i is expressed as p(i) and the number of packets transmitted by managed terminal #i and successfully received by base station 100 (i.e., the number of successful communication packets) is expressed as x, then the total number of packets transmitted by managed terminal #i is estimated to be x/p(i).

Therefore, in the first correction method of this embodiment, the inverse of the communication success rate is set as a correction coefficient, and the correction is performed by multiplying the correction coefficient by the managed channel occupancy rate. For example, the correction coefficient k(i) of managed terminal #i is expressed as k(i) = 1/p(i).

k(i) is determined for each of the N managed terminals. Since the communication success rate p(i) is a value between 0 and 1, k(i) is a real number greater than or equal to 1. Furthermore, the higher the communication success rate (the larger p(i) is), the larger the value of k(i). For example, when the communication success rate p(i) is 1, that is, when there are no packets sent by managed terminal #i that fail to be received, k(i) is 1. Furthermore, when the communication success rate p(i) is 0.5, and half of the packets sent by managed terminal #i are packets that fail to be received, k(i) is 2.

Then, using the measured channel occupancy rate cor(i) of the in-management terminal #i and the correction coefficient k(i), the corrected channel occupancy rate COR _{in_aft} corresponding to the in-management interference is calculated by equation (3).

A corrected channel occupancy rate COR _{out_aft} corresponding to the corrected out-of-control interference in a certain channel #m is derived by subtracting a corrected channel occupancy rate COR _{in_aft} corresponding to the in-control interference obtained by equation (3) from a total channel occupancy rate COR _total in channel #m, as shown in equation (4).

As described above, in the first correction method, the channel occupancy rate based on packets transmitted by an in-management terminal and unsuccessfully received by the base station 100 is corrected based on the communication success rate of the in-management terminal, thereby making it possible to avoid a situation in which the out-of-management interference becomes greater than it actually is, and to appropriately classify in-management interference and out-of-management interference.

Here, instead of the number of successful communication packets, the number of detected terminal identifiers (terminal IDs) and/or the number of detected preambles may be used.

In addition, the communication success rate has been shown to be expressed by variables with the channel occupancy rate and RSSI as parameters, but other parameters may also be used. For example, in a multipath environment, the communication success rate may use the magnitude of delay dispersion as a parameter.

Next, the processing flow in the base station 100 that applies the first correction method will be described. FIG. 6 is a flowchart showing a first example of the processing flow in the base station 100 in this embodiment. In the following, the classification of interference in channel #m will be described as an example. In addition, as an example, managed terminals #1 to #N are assigned to channel #m.

The base station 100 measures the amount of interference (total channel occupancy rate) of channel #m (S101). Note that in the process of S101, the amount of interference of a channel other than channel #m may be measured. In the process of S101, the amount of interference of each channel that the base station 100 can use may be measured. In this case, the base station 100 may perform the processes from S102 onwards for each of the available channels.

The base station 100 calculates the channel occupancy rate of the interference within the management (channel occupancy rate within the management) based on the number of packets that were successfully received and processed and the length of the packets received from each of the terminals within the management #1 to #N (S102).

Based on the total channel occupancy rate measured in S101 and the managed channel occupancy rate calculated in S102, the base station 100 classifies the interference on channel #m into managed interference and unmanaged interference (S103).

The base station 100 corrects the channel occupancy rate of the managed interference calculated in S102 (S104).

The base station 100 corrects the classification result obtained in S103 using the channel occupancy rate of the managed interference corrected in S104 (S105). Then, the flow shown in FIG. 6 ends.

As described above, in the first correction method, the base station 100 performs correction based on the communication success rate of the managed terminal, thereby making it possible to perform interference classification that takes into account interference components based on received signals that were transmitted by the managed terminal and that the base station 100 failed to receive. This makes it possible to avoid, for example, a situation in which non-managed interference in a certain channel becomes greater than it actually is, and allows the base station 100 to perform appropriate channel allocation when allocating channels to each managed terminal, thereby improving the communication characteristics between the base station 100 and the managed terminal.

The above describes a first correction method for correcting the classification of interference into within-management interference and outside-management interference by correcting the channel occupancy rate of within-management interference based on the communication success rate.

Next, a second correction method that is different from the first correction method will be described. In the second correction method, when a packet transmitted from a certain managed terminal #i has not been received, information on the channel occupancy rate of each managed terminal (channel occupancy rate information) held by the base station 100 or a control server connected to the base station 100 is used.

The channel occupancy information for each managed terminal held by the control server may be, for example, a channel occupancy rate equivalent to the managed interference estimated at an observation time prior to observation time T in order to correct the results measured at observation time T.

A condition (selection condition) for selecting between the two methods described above may be set. Then, if the selection condition is met, the second correction method using the channel occupancy rate information held by the control server may be applied, and if the selection condition is not met, the first correction method may be applied.

For example, the selection condition is a condition that determines whether or not past channel occupancy information held by the control server may be used. For example, the selection condition is that the amount of data contained in each packet is a constant value, and that the interval between receiving packets is constant.

In other words, if the amount of data contained in each packet is a constant value and the packets are received at a constant interval, the second correction method is applied; otherwise, the first correction method is applied.

The amount of data contained in each packet being constant may correspond to a packet having a constant amount of data being received a predetermined number of times or more. The reception interval of packets being constant may correspond to the number of reception intervals that are less than a predetermined value among the reception intervals of packets received at an observation time T-t prior to the observation time T being equal to or more than a predetermined number of times.

In other words, if the amount of data contained in each packet is not constant, for example, if the difference in the amount of data between multiple packets is greater than a predetermined amount and there is a large variation in the amount of data between packets, it is not appropriate to use past channel occupancy rates.

Next, we will explain the processing of the base station 100 when switching between the first correction method and the second correction method.

Figure 7 is a flowchart showing a second example of the flow of processing by the base station 100 in this embodiment. Note that in Figure 7, the same processes as those in Figure 6 are denoted by the same reference numerals, and descriptions thereof may be omitted.

After classifying the interference in S103, the base station 100 determines whether the amount of data per packet of packets received at an observation time prior to the observation time T is constant (S201). A constant amount of data of packets received at the base station 100 corresponds to a constant amount of data (amount of transmitted data) of packets transmitted by the managed terminal. For example, if the absolute value of the difference (e.g., standard deviation) between the average amount of data of multiple received packets and the amount of data of each packet is equal to or less than a predetermined value, it may be determined that the amount of data per packet is constant. Alternatively, if the amount of data of multiple received packets falls within a predetermined range, it may be determined that the amount of data per packet is constant. Note that the amount of data may be represented, for example, by the length of the signal or by the number of bits of decoded data.

If the amount of data per packet is constant (YES in S201), the base station 100 judges whether the reception interval of the packets is constant (S202). A constant reception interval in the base station 100 corresponds to a constant transmission interval (transmission period) of the managed terminal. For example, if the absolute value of the difference between the average reception interval of the multiple received packets and each reception interval (e.g., standard deviation) is equal to or less than a predetermined interval, the reception interval may be judged to be constant. Alternatively, if the length (length of time) of the reception interval of the multiple received packets falls within a predetermined range, the reception interval may be judged to be constant.

If the reception interval is a fixed interval (YES in S202), the base station 100 applies the second correction method (S203).

If the amount of data per packet is not constant (NO in S201) or if the interval at which packets are received is not constant (NO in S202), the base station 100 applies the first correction method (S204).

Based on the applied correction method, the base station 100 corrects the interference classification result (S205). Then, the flow shown in FIG. 7 ends.

As described above, by switching between the first and second correction methods, when the amount of transmission data and transmission period of the managed terminal are constant, previously estimated channel occupancy rate information can be used if available, and when the amount of transmission data and transmission period of the managed terminal are not constant, packet error rate information can be used. Therefore, regardless of the propagation environment, amount of transmission data, and transmission period, errors in interference classification can be suppressed. This makes it possible to avoid, for example, a situation in which non-managed interference becomes greater than it actually is in a certain channel, and when base station 100 assigns channels to each managed terminal, it can perform appropriate channel assignment, thereby improving the communication characteristics between base station 100 and managed terminals.

When switching the correction method described above, the switching of the correction method may be determined independently for each managed terminal. Next, the processing flow when switching the correction method independently for each managed terminal will be described.

Figure 8 is a flowchart showing a third example of the flow of processing by the base station 100 in this embodiment. Note that in Figure 8, the same processes as those in Figures 6 and 7 are denoted by the same reference numerals, and descriptions thereof may be omitted.

The base station 100 initializes the terminal IDs (S301). For example, the base station 100 assigns N terminal IDs, #1 to #N, to the N managed terminals assigned to channel #m, and initializes the index i indicating the terminal IDs to 1.

The base station 100 determines whether i is greater than N (S302).

If i is not greater than N (NO in S302), the base station 100 determines whether the amount of data per packet received from managed terminal #i is constant (S303).

If the amount of data per packet is constant (YES in S303), the base station 100 determines whether the reception interval of the packets received from the managed terminal #i is constant (S304).

If the reception interval is a fixed interval (YES in S304), the base station 100 applies the second correction method to correct the in-management interference caused by the in-management terminal #i (S305).

If the amount of data per packet is not constant (NO in S303) or if the packet reception interval is not constant (NO in S304), the base station 100 applies the first correction method to correct the in-management interference caused by the in-management terminal #1 (S306).

The base station 100 adds 1 to i (S307). Then, the process of S302 is executed.

If i is greater than N (YES in S302), that is, when the base station 100 has finished selecting a correction method for each of the managed terminals assigned to channel #m, the interference classification result is corrected based on the correction method of each selection result (S308). Then, the flow shown in FIG. 8 ends.

As described above, the process shown in FIG. 8 allows the base station 100 to select a correction method appropriate for each managed terminal, thereby enabling more appropriate correction of the classification results.

For example, a fixed correction method may be applied to a specific terminal among the managed terminals. For example, the specific terminal is a terminal whose communication quality is more stable for a long period of time than other managed terminals. The specific terminal may be, for example, a terminal located near a base station, a terminal located in a place with few obstructions between the base station and the terminal, or a terminal with a longer transmission period than other terminals. Alternatively, a terminal that regularly transmits a small amount of data may be applied as the specific terminal. For example, a terminal that is mounted on a meter for electricity or gas and transmits data on the amount of electricity or gas used, a terminal used to watch over elderly people, a terminal used to notify which parking spaces are available in a parking lot, or the like, that does not need to notify image information may be applied. For example, whether a certain managed terminal is a specific terminal may be determined in advance based on the type of data transmitted by the managed terminal, the purpose of the managed terminal, the location of the managed terminal, etc. Alternatively, whether or not a certain managed terminal is a specific terminal may be dynamically determined by the base station 100 based on information notified from the managed terminal (information about the distance between the base station and the managed terminal, information about radio wave propagation such as power attenuation or multipath).

Figure 9 is a flowchart showing a fourth example of the flow of processing by the base station 100 in this embodiment. Note that in Figure 9, the same processes as those in Figures 6 to 8 are denoted by the same reference numerals, and descriptions thereof may be omitted.

If i is not greater than N (NO in S302), the base station 100 determines whether the managed terminal #i is a specific terminal (S401). For example, the base station 100 makes this determination based on information about the terminal type acquired from the managed terminal #i.

If the managed terminal #i is a specific terminal (YES in S401), the base station 100 applies the second correction method to correct the managed interference caused by the managed terminal #i (S305).

If managed terminal #i is not a specific terminal (NO in S401), the base station 100 executes the process of S303.

Here, when the transmission cycle is long, it may take time to collect the information necessary to select the correction method to be used from the first correction method and the second correction method. In such a case, the correction method to be used may be selected from the first correction method and the second correction method before sufficient information has been collected, and it may not be possible to select the optimal correction method. In the above example, a fixed correction method is applied to a managed terminal that corresponds to a specific terminal, so that the optimal correction method can be selected even for a terminal that has a longer transmission cycle than other terminals.

In the above, an example was shown in which the correction method to be used was determined independently for each managed terminal, but the correction method to be used may also be determined for each observation time period. Next, a process flow for when the correction method is switched for each observation time period will be described.

Figure 10 is a flowchart showing a fifth example of the flow of processing by the base station 100 in this embodiment. Note that in Figure 10, the same processes as those in Figures 6 to 9 are denoted by the same reference numerals, and descriptions thereof may be omitted.

After classifying the interference in S103, the base station 100 sets a correction time period for correcting the classified interference (S501). For example, the base station 100 divides the observation time period into multiple time periods and sets one of the divided time periods as the correction time period.

The base station 100 determines whether the amount of data per packet of received packets is constant during the set correction time period (S502). For example, if the absolute value of the difference (e.g., standard deviation) between the average amount of data of the multiple received packets and the amount of data of each packet is equal to or less than a predetermined value, it may be determined that the amount of data per packet is constant. Alternatively, if the amount of data of the multiple received packets falls within a predetermined range, it may be determined that the amount of data per packet is constant.

If the amount of data per packet is constant (YES in S502), the base station 100 determines whether the reception interval of packets is constant during the set correction time period (S503). For example, if the absolute value of the difference between the average reception interval of the multiple received packets and each reception interval (e.g., standard deviation) is equal to or less than a predetermined interval, the reception interval may be determined to be constant. Alternatively, if the length (length of time) of the reception interval of the multiple received packets falls within a predetermined range, the reception interval may be determined to be constant.

If the reception interval is a fixed interval (YES in S503), the base station 100 applies the second correction method (S504).

If the amount of data per packet is not constant (NO in S502), or if the interval at which packets are received is not constant (NO in S503), the base station 100 applies the first correction method (S505).

Then, the base station 100 corrects the interference classification result according to the correction method applied for each time period (S506). Then, the flow shown in FIG. 10 ends.

As described above, the process shown in FIG. 10 allows the base station 100 to select a correction method appropriate for each time period, thereby enabling more appropriate correction of the classification results.

For example, a fixed correction method may be applied during a specific time period. For example, a specific time period is a time period during which each terminal does not transmit a large amount of information, such as image information, and/or a time period during which the amount of traffic is relatively small. Alternatively, a time period from when each terminal starts communication until a predetermined time has elapsed may be applied as the specific time period. For example, the specific time period may be determined in advance, or may be dynamically determined by the base station 100 or the like. For example, the specific time period may be determined based on the type and amount of data transmitted and received during each time period.

Figure 11 is a flowchart showing a sixth example of the flow of processing by the base station 100 in this embodiment. Note that in Figure 11, the same processes as those in Figures 6 to 10 are denoted by the same reference numerals, and descriptions thereof may be omitted.

After setting the time period in S501, the base station 100 determines whether the set time period is a specific time period (S601). For example, the base station 100 may make this determination by referring to communication history such as the amount of traffic for each past time period.

If the time period is a specific time period (YES in S601), the base station 100 applies the second correction method to correct the channel occupancy rate of the managed interference in the specific time period (S504).

If the time period is not a specific time period (NO in S601), the base station 100 executes the process of S502.

Here, it may take time to collect information necessary to select the correction method to be used from the first correction method and the second correction method, for example, immediately after the start of communication. In such a case, the correction method to be used may be selected from the first correction method and the second correction method before sufficient information has been collected, and it may not be possible to select the optimal correction method. In the above example, a fixed correction method is applied in a specific time period, making it possible to select the optimal correction method even immediately after the start of communication.

In addition, in each of the above examples, the communication method between the base station 100 and the managed terminal is not limited. In addition, the correction method to be used may be determined from the first correction method and the second correction method depending on the communication method between the base station 100 and the managed terminal.

In the following, as an example, when the communication method between the base station 100 and the managed terminal includes Wi-Fi and LPWA, a first correction method is always used for Wi-Fi, and the correction method to be used for LPWA is determined from the first correction method and the second correction method.

Figure 12 is a flowchart showing a seventh example of the flow of processing by the base station 100 in this embodiment. Note that in Figure 12, the same processes as those in Figures 6 to 11 are denoted by the same reference numerals, and descriptions thereof may be omitted.

After classifying the interference in S103, the base station 100 determines whether the communication method used to communicate with the managed terminal is Wi-Fi (S701).

If the communication method is Wi-Fi (YES in S701), the base station 100 applies the first correction method (S204).

If the communication method is not Wi-Fi (NO in S701), the base station 100 executes the process of S201.

Next, as an example different from the above, when the communication method between the base station 100 and the managed terminal includes Wi-Fi and LPWA, an example will be described in which the second correction method is always used in LPWA, and the correction method to be used in Wi-Fi is determined from the first correction method and the second correction method.

Figure 13 is a flowchart showing an eighth example of the flow of processing by the base station 100 in this embodiment. Note that in Figure 13, the same processes as those in Figures 6 to 12 are given the same reference numerals, and descriptions thereof may be omitted.

After classifying the interference in S103, the base station 100 determines whether the communication method used to communicate with the managed terminal is LPWA (S801).

If the communication method is LPWA (YES in S801), the base station 100 applies the second correction method (S203).

If the communication method is not LPWA (NO in S801), the base station 100 executes the process of S201.

As described above, the processing shown in Figures 12 and 13 allows the base station 100 to select a correction method appropriate for each communication method, thereby enabling more appropriate correction of the classification results.

In addition, since there are multiple types of communication methods for LPWA, even when the communication method is LPWA, the correction method to be used may be determined from the first correction method and the second correction method depending on the type of communication method of the LPWA. For example, there may be a case where the communication method is a mixture of the LoRa method and the Wi-SUN method, but it is generally considered that the Wi-SUN method communicates a larger amount of data than the LoRa method. For this reason, when the communication method is the LoRa method, the second correction method is always used, and when the communication method is the Wi-SUN method, the correction method to be used may be determined from the first correction method and the second correction method.

Here, LPWA generally has a longer transmission cycle than Wi-Fi. In particular, the LoRa method has a longer transmission cycle than Wi-Fi. When a communication method with a long transmission cycle is used, it may take time to collect information required to select a correction method to be used from the first correction method and the second correction method. In such a case, the correction method to be used may be selected from the first correction method and the second correction method before sufficient information has been collected, and it may not be possible to select the optimal correction method. In the above example, a fixed correction method is applied to a specific communication method, so that the optimal correction method can be selected even when a communication method with a long transmission cycle is used.

The above examples may be combined. For example, the correction method may be set independently for each managed terminal and for each time period. Alternatively, the correction method may be set independently for each managed terminal depending on the communication method.

As described above, in this embodiment, when base station 100 classifies interference into in-management interference and interference outside of management, it corrects the classified interference inside management based on the communication success rate of the in-management terminal that transmits a signal caused by the in-management interference. With this configuration, it is possible to improve communication characteristics by appropriately classifying interference and performing control (e.g., channel allocation) that takes into account the classified interference.

Note that, although the communication method in the above-described embodiment is LPWA or Wi-Fi, the present disclosure is not limited to this.

In addition, at least a part of the configuration of the base station 100 in the above-described embodiment may be included in a device other than the base station 100 (for example, a control device connected to the network to which the base station 100 is connected). In addition, a part or all of the processing of the base station 100 in the above-described embodiment may be executed in a device other than the base station 100.

The term "part" in the above embodiment may be replaced with other terms such as "circuitry", "device", "unit", or "module".

In addition, the term "channel" in the above embodiments may be replaced with other terms such as "frequency," "frequency channel," "band," "carrier," "subcarrier," or "(frequency) resource."

In addition, the term "correction" in the above embodiments may be replaced with other terms such as "compensation," "modification," "correction," "update," or "complement."

This disclosure can be realized as software, hardware, or software in conjunction with hardware.

Each functional block used in the description of the above embodiments may be realized, in part or in whole, as an LSI, which is an integrated circuit, and each process described in the above embodiments may be controlled, in part or in whole, by one LSI or a combination of LSIs. The LSI may be composed of individual chips, or may be composed of one chip that contains some or all of the functional blocks. The LSI may have data input and output. Depending on the level of integration, the LSI may be called an IC, system LSI, super LSI, or ultra LSI.

The integrated circuit method is not limited to LSI, and may be realized by a dedicated circuit, a general-purpose processor, or a dedicated processor. In addition, a field programmable gate array (FPGA) that can be programmed after LSI manufacturing, or a reconfigurable processor that can reconfigure the connections and settings of circuit cells inside the LSI, may be used. The present disclosure may be realized as digital processing or analog processing.

Furthermore, if an integrated circuit technology that can replace LSI emerges due to advances in semiconductor technology or other derived technologies, it is natural that such technology can be used to integrate functional blocks. The application of biotechnology, etc. is also a possibility.

The present disclosure may be implemented in any type of apparatus, device, or system with communication capabilities (collectively referred to as communication devices). Non-limiting examples of communication devices include telephones (e.g., mobile phones, smartphones, etc.), tablets, personal computers (PCs) (e.g., laptops, desktops, notebooks, etc.), cameras (e.g., digital still/video cameras), digital players (e.g., digital audio/video players, etc.), wearable devices (e.g., wearable cameras, smartwatches, tracking devices, etc.), game consoles, digital book readers, telehealth/telemedicine devices, communication-enabled vehicles or mobile transport (e.g., automobiles, airplanes, ships, etc.), and combinations of the above-mentioned devices.

The communication device is not limited to portable or mobile devices, but also includes any type of equipment, device, or system that is non-portable or fixed, such as smart home devices (home appliances, lighting equipment, smart meters or measuring devices, control panels, etc.), vending machines, and any other "things" that may exist on an IoT (Internet of Things) network.

Communications include data communication via cellular systems, wireless LAN systems, communication satellite systems, etc., as well as data communication via combinations of these.

The communication device also includes devices such as controllers and sensors that are connected or coupled to a communication device that performs the communication functions described in this disclosure. For example, the communication device includes a controller or sensor that generates control signals or data signals used by the communication device to perform the communication functions of the communication device.

Communication equipment also includes infrastructure facilities, such as base stations, access points, and any other equipment, devices, or systems that communicate with or control the various non-limiting devices listed above.

Although various embodiments have been described above with reference to the drawings, it goes without saying that the present disclosure is not limited to such examples. It is clear that a person skilled in the art can come up with various modified or revised examples within the scope of the claims, and it is understood that these also naturally fall within the technical scope of the present disclosure. Furthermore, the components in the above embodiments may be combined in any manner as long as it does not deviate from the spirit of the disclosure.

Specific examples of the present disclosure have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples given above.

This disclosure is suitable for wireless communication systems.

REFERENCE SIGNS LIST 100 Base station 101 Receiving unit 102 Communication quality measuring unit 103 Preamble detecting unit 104 Interference classifying unit 105 Correcting unit 106 Demodulating/decoding unit 107 Allocation control unit 108 Control signal generating unit 109 Encoding/modulating unit 110 Transmitting unit

Claims (12)

A base station supporting a first wireless system and belonging to a first network,
a measurement unit that measures a first interference amount based on a reception signal received at a specific measurement time;
an estimation unit that supports the first wireless system and estimates a second interference amount based on a received signal determined to have been transmitted by a first wireless device belonging to the first network;
a correction unit that corrects the second interference amount based on a communication success rate of the first wireless device;
a determination unit that determines a third interference amount based on a signal transmitted by a second wireless device that does not belong to the first network, from the first interference amount and the corrected second interference amount;
A base station comprising: The correction unit corrects the second amount of interference by using a first correction method;
the first correction method is a method of multiplying the second interference amount by a coefficient determined based on a communication success rate of the first wireless device;
The base station according to claim 1 . the correction unit corrects the second amount of interference by using a second correction method when a determination condition is satisfied at the measurement time;
the second correction method is a method of replacing a fourth amount of interference corrected using the first correction method at a time before the measurement time with the second amount of interference estimated by the estimation unit.
The base station according to claim 2. the correction unit determines, for each of the first wireless devices, whether to correct the second interference amount by using the first correction method or to correct the second interference amount by using the second correction method.
The base station according to claim 3. the correction unit corrects the second interference amount by using the second correction method for the first wireless device that satisfies a specific condition.
The base station according to claim 4. the specific condition being that an amount of data included in the signal received from the first wireless device is within a certain range, and that a length of a reception interval of the signal received from the first wireless device is within a predetermined range;
The base station according to claim 5. the correction unit determines, for each of the plurality of measurement times, whether to correct the second amount of interference by using the first correction method or to correct the second amount of interference by using the second correction method.
The base station according to claim 3. the correction unit corrects the second amount of interference by using the second correction method during the measurement time that satisfies a specific condition.
The base station according to claim 7. The specific condition is that an amount of data included in the signal received during the measurement time falls within a certain range, and that a length of a reception interval of the signal received during the measurement time falls within a predetermined range.
The base station according to claim 8. the correction unit determines whether to correct the second interference amount using the first correction method or to correct the second interference amount using the second correction method according to a communication method between the base station and the first wireless device.
The base station according to claim 3. the determination condition is that a difference in length of a signal transmitted by the first wireless device at a time before the measurement time is equal to or less than a first threshold, and a difference in reception intervals of a signal transmitted by the first wireless device at a time before the measurement time is equal to or less than a second threshold.
The base station according to claim 3. A base station supporting a first wireless system and belonging to a first network,
measuring a first amount of interference based on a received signal received at a specific measurement time;
estimating a second amount of interference based on a received signal determined to have been transmitted by a first wireless device supporting the first wireless system and belonging to the first network;
correcting the second interference amount based on a communication success rate of the first wireless device;
determining a third amount of interference based on a signal transmitted by a second wireless device not belonging to the first network, from the first amount of interference and the corrected second amount of interference;
Control methods.

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