Wireless system and communication method

Abstract

To provide a wireless system that suppresses an influence of a radio wave interference inside a metal board.SOLUTION: A wireless system includes: a master unit provided inside a metal board; a plurality of slave units provided inside the board and communicating with the master unit by wireless communication; and a relay unit provided inside the board and communicating with the master unit and the slave unit by the wireless communication and relaying the communication between the master unit and the slave unit. Any one of the plurality of slave units communicates with the master unit via the relay unit when a first radio wave intensity with the master unit is lower than a lower radio wave intensity of a second radio wave intensity with the relay unit and a third radio wave intensity between the master unit and the relay unit.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to wireless systems and communication methods. [Background technology]

[0002] Patent Document 1 discloses a panel device that includes a housing and a plurality of devices housed in the housing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-096511 Summary of the Invention [Problem to be solved by the invention]

[0004] When wireless communication is performed inside a metal panel, radio waves are reflected by the metal surface, causing radio wave interference. Because radio wave interference occurs inside the panel, the radio wave strength is not uniform regardless of the distance between the parent and child devices, resulting in an uneven distribution of strength.

[0005] The present disclosure provides a wireless system that reduces the effects of radio wave interference inside a metal panel. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, a wireless system is provided, comprising: a parent unit provided inside a metal panel; a plurality of child units provided inside the panel and communicating with the parent unit via wireless communication; and a repeater provided inside the panel, communicating with the parent unit and the child units via wireless communication and relaying communication between the parent unit and the child units, wherein a first child unit of any one of the plurality of child units communicates with the parent unit via the repeater when a first radio wave strength between the parent unit and the repeater is lower than the lower of a second radio wave strength between the repeater and the parent unit and a third radio wave strength between the parent unit and the repeater. [Effects of the Invention]

[0007] According to the wireless system of the present disclosure, the effects of radio wave interference inside the metal panel can be reduced. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing an outline of a wireless system according to the first embodiment. [Figure 2] FIG. 2 is a diagram illustrating the configuration of the master device in the wireless system according to the first embodiment. [Figure 3] FIG. 3 is a diagram illustrating the configuration of a slave device in the wireless system according to the first embodiment. [Figure 4] FIG. 4 is a diagram illustrating the configuration of a repeater in the wireless system according to the first embodiment. [Figure 5] FIG. 5 is a flowchart illustrating processing in the wireless system according to the first embodiment. [Figure 6] FIG. 6 is a flowchart illustrating a modified example of processing in the wireless system according to the first embodiment. [Figure 7] FIG. 7 is a diagram showing an outline of a wireless system according to the second embodiment. [Figure 8] FIG. 8 is a flowchart illustrating processing in the wireless system according to the second embodiment. [Figure 9] FIG. 9 is a flowchart illustrating a modified example of processing in the wireless system according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, each embodiment of the present invention will be described with reference to the accompanying drawings. Note that, in the description of the specification and drawings relating to each embodiment, components having substantially the same or corresponding functional configurations may be designated by the same reference numerals, and redundant description may be omitted. Also, for ease of understanding, the scale of each part in the drawings may differ from the actual scale.

[0010] First Embodiment A wireless system according to a first embodiment will be described. The wireless system according to the first embodiment includes a master unit, multiple slave units, and a repeater, which are provided inside a metal panel. Any of the multiple slave units in the wireless system according to the first embodiment communicates with the master unit via wireless communication. The repeater in the wireless system according to the first embodiment communicates with the master unit and the slave units via wireless communication. The repeater in the wireless system according to the first embodiment relays communication between the master unit and the slave units. A first slave unit, one of the multiple slave units in the wireless system according to the first embodiment, communicates with the master unit via the repeater when the first radio wave strength between the master unit and the repeater is lower than the lower of the second radio wave strength between the repeater and the third radio wave strength between the master unit and the repeater.

[0011] The wireless system according to the first embodiment will be described in detail below. Fig. 1 is a diagram showing an outline of a wireless system 1, which is an example of the wireless system according to the first embodiment.

[0012] The wireless system 1 includes a master unit 10, a plurality of slave units 20, and a repeater 30 inside a metal panel 40. The wireless system 1 performs communication between the master unit 10 and each of the plurality of slave units 20. Some of the plurality of slave units 20 in the wireless system 1 communicate with the master unit 10 via the repeater 30. The wireless system 1 performs communication with an external device 100 wirelessly or via a wired connection.

[0013] [Base unit 10] The master device 10 communicates with each of the multiple slave devices 20. The master device 10 also communicates with any of the multiple slave devices 20 via a repeater 30. Furthermore, the master device 10 communicates with an external device 100.

[0014] When communicating with each of the multiple slave devices 20, the master device 10 communicates via wireless communication. When communicating with the repeater 30, the master device 10 communicates via wireless communication. The wireless communication may be, for example, communication standardized by the Institute of Electrical and Electronics Engineers (IEEE). The wireless communication may be, for example, communication via a wireless LAN (Local Area Network) standardized as IEEE 802.11. The wireless communication may be, for example, communication via a wireless PAN (Personal Area Network) standardized as IEEE 802.15.

[0015] The following describes the configuration of the master device 10. Fig. 2 is a diagram illustrating the configuration of the master device 10 in the wireless system 1, which is an example of a wireless system according to the first embodiment.

[0016] The base unit 10 includes a control circuit 11, a wireless communication circuit 12, and a communication circuit 13.

[0017] The control circuit 11 performs control in the base unit 10. The control circuit 11 controls each of the wireless communication circuit 12 and the communication circuit 13. The control circuit 11 includes, for example, a processor such as a CPU (Central Processing Unit) and memories such as a RAM (Random Access Memory) and a ROM (Read Only Memory). The control circuit 11 may also include an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), etc. The control circuit 11 performs desired processing by executing a program loaded into the memory by the CPU.

[0018] The wireless communication circuit 12 communicates with each of the slave device 20 and the relay device 30 by wireless communication under the control of the control circuit 11. The wireless communication circuit 12 is connected to an antenna 12a.

[0019] The communication circuit 13 communicates with the external device 100 under the control of the control circuit 11. The communication with the external device 100 may be, for example, communication via a wired LAN standardized by IEEE 802.3. Alternatively, the communication with the external device 100 may be communication via a mobile communication system such as a mobile phone network.

[0020] [Handset 20] The slave device 20 communicates with the master device 10. The slave device 20 communicates with the master device 10 by direct wireless communication. The slave device 20 also communicates with the master device 10 via a repeater 30.

[0021] The following describes the configuration of the slave device 20. Fig. 3 is a diagram illustrating the configuration of the slave device 20 in the wireless system 1, which is an example of a wireless system according to the first embodiment.

[0022] The slave device 20 includes a control circuit 21, a wireless communication circuit 22, and an input / output circuit 24.

[0023] The control circuit 21 performs control in the slave device 20. The control circuit 21 controls each of the wireless communication circuit 22 and the input / output circuit 24. The control circuit 21 includes a CPU and the like, similar to the control circuit 11. The control circuit 21 performs desired processing by executing a program that the CPU has loaded into a memory.

[0024] The wireless communication circuit 22 communicates with each of the master device 10 and the repeater device 30 by wireless communication under the control of the control circuit 21. The wireless communication circuit 22 is connected to an antenna 22a.

[0025] The input / output circuit 24 inputs and outputs data to and from the external device 50. Data is input to the input / output circuit 24 from the external device 50. The input / output circuit 24 also outputs data to the external device 50. The external device 50 is, for example, a detector such as a current meter, a voltage meter, or a power meter. The input / output circuit 24 is connected to the external device 50 by, for example, serial communication, parallel communication, or the like. The input / output circuit 24 communicates by, for example, USB (Universal Serial Bus), IEEE 488, SPI (Serial Peripheral Interface), I2C, or the like.

[0026] [Repeater 30] The repeater 30 communicates with the parent device 10 via wireless communication. The repeater 30 also communicates with the child device 20 via wireless communication. The repeater 30 also communicates wirelessly with both the parent device 10 and the child device 20, thereby relaying communication from the parent device 10 to the child device 20 and communication from the child device 20 to the parent device 10.

[0027] The following describes the configuration of the repeater 30. Fig. 4 is a diagram illustrating the configuration of the repeater 30 in the wireless system 1, which is an example of a wireless system according to the first embodiment.

[0028] The repeater 30 includes a control circuit 31 and a wireless communication circuit 32 .

[0029] The control circuit 31 performs control in the repeater 30. The control circuit 31 controls the wireless communication circuit 32. The control circuit 31 includes a CPU and the like, similar to the control circuits 11 and 21. The control circuit 31 performs desired processing by executing a program that the CPU has loaded into a memory.

[0030] The wireless communication circuit 32 communicates with the master device 10 and the repeater device 30 by wireless communication under the control of the control circuit 31. The wireless communication circuit 32 is connected to an antenna 32a.

[0031] Next, a description will be given of processing in the wireless system 1. Fig. 5 is a flow diagram illustrating processing in the wireless system 1, which is an example of a wireless system according to the first embodiment. By explaining the processing in the wireless system 1, steps included in the communication method according to this embodiment will be described.

[0032] In the following description, an example will be described in which processing is performed by the control circuit 11 in the master device 10. Note that similar processing may also be performed in the slave device 20 or the repeater device 30.

[0033] (Step S10) First, the control circuit 11 acquires the radio wave intensity A between the master device 10 and the slave device 20 (a step of acquiring the radio wave intensity A between the master device and the slave device). For example, the control circuit 11 controls the wireless communication circuit 12 in the master device 10 to acquire the radio wave intensity A in communication with the slave device 20. For example, the wireless communication circuit 12 acquires the radio wave intensity (RSSI: Received Signal Strength Indicator) from the slave device 20.

[0034] (Step S20) Next, the control circuit 11 determines whether the acquired radio wave intensity A between the master unit 10 and the slave unit 20 is equal to or greater than a threshold value. The threshold value indicates, for example, a radio wave intensity at which stable communication is possible.

[0035] If the radio wave intensity A is equal to or greater than the threshold value (YES in step S20), the control circuit 11 determines that the radio wave intensity is sufficient, and proceeds to step S70 to connect the master unit 10 and the slave unit 20. That is, the control circuit 11 selects a route for connecting the master unit 10 and the slave unit 20 directly by wireless communication. If the radio wave intensity A is less than the threshold value (NO in step S20), the control circuit 11 proceeds to step S30.

[0036] (Step S30) If the radio wave intensity A is less than the threshold value (NO in step S20), the control circuit 11 acquires the radio wave intensity B between the slave device 20 and the repeater 30 (a step of acquiring the radio wave intensity B between the slave device and the repeater). For example, the control circuit 31 controls the wireless communication circuit 32 in the repeater 30 to acquire the radio wave intensity B in communication with the slave device 20. Then, the control circuit 31 transmits the acquired radio wave intensity B to the master device 10. The control circuit 11 acquires the radio wave intensity B between the slave device 20 and the repeater 30 transmitted from the repeater 30.

[0037] (Step S40) Next, the control circuit 11 acquires the radio wave intensity C between the master device 10 and the repeater 30 (a step of acquiring the radio wave intensity C between the master device and the repeater). For example, the control circuit 11 controls the wireless communication circuit 12 in the master device 10 to acquire the radio wave intensity C in communication with the repeater 30.

[0038] Note that the radio wave intensity C between the base unit 10 and the repeater 30 does not change significantly once the base unit 10 and the repeater 30 are installed. Therefore, for example, the radio wave intensity C between the base unit 10 and the repeater 30 may be measured at the time of installation and the measurement result may be stored in memory. Then, in step S40, the control circuit 11 may obtain the radio wave intensity C by reading out the radio wave intensity C stored in the memory.

[0039] The radio wave intensity C stored in the memory may be updated by measuring the radio wave intensity C between the master device 10 and the repeater device 30 at a predetermined period or the like.

[0040] (Step S50) Next, control circuit 11 determines whether radio wave intensity A is lower than the lower of radio wave intensity B and radio wave intensity C. If radio wave intensity A is higher than the lower of radio wave intensity B and radio wave intensity C (NO in step S50), control circuit 11 proceeds to step S70 to connect master unit 10 and slave unit 20. That is, control circuit 11 selects a route for connecting master unit 10 and slave unit 20 directly by wireless communication. If radio wave intensity A is lower than the lower of radio wave intensity B and radio wave intensity C (YES in step S50), control circuit 11 proceeds to step S60.

[0041] (Step S60) If radio wave intensity A is lower than the lower of radio wave intensity B and radio wave intensity C (YES in step S50), control circuit 11 connects slave device 20 and repeater 30. That is, control circuit 11 selects a route connecting slave device 20 and repeater 30. In other words, slave device 20 communicates with master device 10 via repeater 30.

[0042] (Step S70) The control circuit 11 connects the master device 10 and the slave device 20. That is, the control circuit 11 selects a route for connecting the master device 10 and the slave device 20 directly by wireless communication. In other words, the slave device 20 is directly connected to the master device 10.

[0043] In the wireless system 1, the above processing is performed by all of the slave devices 20 that are performing communication among the plurality of slave devices 20.

[0044] In the above example, in step S20, if the radio wave intensity A is equal to or greater than the threshold, a route connecting the master unit 10 and the slave unit 20 is selected. However, even if the radio wave intensity A is equal to or greater than the threshold, a case of connecting to the master unit 10 via the repeater 30 may be selected. In other words, in the above example, the process of step S20 may be omitted.

[0045] An example in which step S20 is omitted is shown in Fig. 6. Fig. 6 is a flowchart illustrating a modified example of the processing in the wireless system 1, which is an example of the wireless system according to the first embodiment.

[0046] According to the wireless system of the first embodiment, by selecting between direct communication between the slave device and the master device and communication between the slave device and the master device via a repeater, stable communication is possible even if radio wave interference inside the metal panel causes uneven radio wave strength. In other words, according to the wireless system of the first embodiment, the effects of radio wave interference inside the metal panel can be suppressed.

[0047] For example, in a system that performs wireless communication inside a metal panel, radio waves reflect off the surface of the metal, causing radio wave interference. Because of radio wave interference, the radio wave strength is not proportional to the distance between the master and slave units, resulting in an uneven distribution of strength and areas with low radio wave strength. While it is possible to increase the radio wave strength by changing the installation location of the master or slave unit, it may be difficult to change the installation location of the master and slave units due to other contents inside the panel.

[0048] According to the wireless system of the first embodiment, even if there are areas where the radio wave strength is low, the radio wave strength can be improved by switching to communication via a repeater in areas where the radio wave strength between the parent device and the child device is low.

[0049] Second Embodiment A wireless system according to a second embodiment will now be described. The wireless system according to the first embodiment includes a repeater, but in the wireless system according to a second embodiment, at least one of a plurality of slave devices functions as a repeater.

[0050] The wireless system according to the second embodiment includes a master unit and multiple slave units provided inside a metal panel. Any of the slave units in the wireless system according to the second embodiment communicates with the master unit via wireless communication. In the wireless system according to the second embodiment, a first slave unit whose radio wave strength with the master unit is below a threshold communicates with the master unit via a second slave unit different from the first slave unit.

[0051] In addition, for the second handset in the wireless system according to the second embodiment, among the multiple handset units, the maximum radio wave strength is the lower of the fourth radio wave strength between the parent unit and the second handset and the fifth radio wave strength between the first handset and the second handset.

[0052] The wireless system according to the second embodiment will be described in detail below. Fig. 7 is a diagram showing an outline of a wireless system 2, which is an example of the wireless system according to the second embodiment.

[0053] The wireless system 2 includes a master unit 10 and a plurality of slave units 20 inside a metal panel 40. The wireless system 2 performs communication between the master unit 10 and each of the plurality of slave units 20. In the wireless system 2, some of the plurality of slave units 20 also function as repeaters. In the example of the wireless system 2, the slave unit 25 also functions as a repeater. The wireless system 2 performs communication with the external device 100 wirelessly or via a wired connection.

[0054] For details of the master device 10 and the slave device 20, please refer to the description of the wireless system according to the first embodiment, and detailed description thereof will be omitted here.

[0055] Next, a description will be given of processing in the wireless system 2. Fig. 8 is a flow diagram illustrating processing in the wireless system 2, which is an example of a wireless system according to the second embodiment. By explaining the processing in the wireless system 2, steps included in the communication method according to this embodiment will be described.

[0056] In the following description, an example will be described in which processing is performed by the control circuit 11 in the parent device 10. Note that the same processing may also be performed in the child device 20.

[0057] For steps S10, S20 and S70, the description of the wireless system according to the first embodiment should be referred to, and detailed description thereof will be omitted here. When the process starts, the number of routes n, which will be described later, is set to 1.

[0058] (Step S130) In step S20, if the radio wave intensity A is less than the threshold value (NO in step S20), the control circuit 11 searches for the minimum radio wave intensity when a first terminal of the multiple terminals 20 and a second terminal of the multiple terminals 20 different from the first terminal serve as a repeater. The minimum radio wave intensity is the minimum of the radio wave intensity between the first terminal and the second terminal and the radio wave intensity between the base unit 10 and the second terminal. Then, the control circuit 11 identifies the second terminal with the maximum minimum radio wave intensity when all the second terminals different from the first terminal serve as repeaters. Then, the control circuit 11 determines the route formed by the combination of the first terminal and the second terminal with the maximum minimum radio wave intensity when all the second terminals different from the first terminal serve as repeaters as a tentative route.

[0059] (Step S140) Next, it is determined whether the lowest radio wave intensity D on the tentative route is equal to or greater than a threshold. If the radio wave intensity D is equal to or greater than the threshold (YES in step S140), control circuit 11 proceeds to step S180, where it connects master unit 10 and slave unit 20 via the tentative route. That is, control circuit 11 selects the tentative route as the route connecting master unit 10 and slave unit 20. If the radio wave intensity D is less than the threshold (NO in step S140), control circuit 11 proceeds to step S150.

[0060] (Step S150) The control circuit 11 adds 1 to the number of routes n.

[0061] (Step S160) Next, the control circuit 11 determines whether the number of via points n exceeds a predetermined threshold. If the number of via points n exceeds the predetermined threshold (YES in step S160), the control circuit 11 proceeds to step S180 and connects the parent device 10 and the child device 20 via the tentative route. That is, the control circuit 11 selects the tentative route as the route connecting the parent device 10 and the child device 20. If the number of via points n does not exceed the predetermined threshold (NO in step S160), the control circuit 11 proceeds to step S170.

[0062] (Step S170) The control circuit 11 searches for the minimum radio wave strength when a first handset of the multiple handset devices 20 and n second handset devices different from the first handset among the multiple handset devices 20 are used as repeaters. The minimum radio wave strength is the minimum radio wave strength between the first handset device, the n second handset devices, and the base device 10. Then, the control circuit 11 identifies the combination of the first handset device and the n second handset devices that has the maximum minimum radio wave strength among all combinations of the first handset device and the n second handset devices. The tentative route is then determined to be the route formed by the combination of the first handset device and the second handset device that has the maximum minimum radio wave strength among all combinations of the first handset device and the n second handset devices different from the first handset device.

[0063] After performing the above processing, the control circuit 11 returns to step S140 and repeats the processing.

[0064] (Step S180) The control circuit 11 connects the master unit 10 and the slave unit 20 via the current tentative route.

[0065] In the above example, in step S20, if the radio wave intensity A is equal to or greater than the threshold, a route for connecting the base unit 10 and the slave unit 20 is selected, but even if the radio wave intensity A is equal to or greater than the threshold, a case of connecting to the base unit 10 via another slave unit 20 may be selected. In other words, in the above example, the processing of step S20 may be omitted.

[0066] An example in which step S20 is omitted is shown in Fig. 9. Fig. 9 is a flowchart illustrating a modified example of processing in the wireless system 2, which is an example of the wireless system according to the second embodiment.

[0067] In the example of FIG. 9, in step S190, the route with the greatest minimum radio wave intensity among the tentative routes 1 to n is selected as the route connecting the slave unit and the master unit.

[0068] According to the wireless system of the second embodiment, by selecting between a case where the slave device communicates directly with the master device and a case where another slave device communicates with the master device using a repeater, stable communication is possible even if radio wave interference inside the metal panel causes uneven radio wave strength. In other words, according to the wireless system of the second embodiment, the effects of radio wave interference inside the metal panel can be suppressed.

[0069] According to the wireless system of the second embodiment, even if there are areas where the radio wave strength is low, the radio wave strength can be improved by switching to communication via a slave unit that also functions as a repeater in areas where the radio wave strength between the master unit and the slave unit is low.

[0070] The application of the wireless system according to the present embodiment will be described below. The wireless system according to each of the first and second embodiments can be applied as, for example, a power monitoring module that monitors power in a distribution board.

[0071] It should be noted that the embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive, and the above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims. [Explanation of symbols]

[0072] 1, 2 Radio system 10 Base unit 11 Control circuit 20, 25 Handset 30 Repeater 40 discs 100 External devices

Claims

1. a master unit provided inside a metal panel; a plurality of slave units provided inside the panel and configured to communicate with the master unit via wireless communication; a repeater provided inside the panel, communicating with the parent device and the child device via wireless communication and relaying communication between the parent device and the child device; Equipped with a first handset among the plurality of handset devices communicates with the parent device via the repeater when a first radio wave intensity between the first handset and the parent device is lower than a second radio wave intensity between the first handset and the repeater and a third radio wave intensity between the parent device and the repeater, whichever is lower; Radio system.

2. When the first radio wave intensity is higher than the lower one of the second radio wave intensity and the third radio wave intensity, the first slave device directly communicates with the master device.

2. The wireless system of claim 1.

3. The slave device, whose radio wave strength between the slave device and the master device is equal to or greater than a threshold, communicates directly with the master device.

3. The wireless system according to claim 1.

4. a master unit provided inside a metal panel; a plurality of slave units provided inside the panel and configured to communicate with the master unit via wireless communication; Equipped with a first handset whose radio wave strength between itself and the base unit is less than a threshold communicates with the base unit via a second handset different from the first handset; Radio system.

5. The second handset is configured such that, among the plurality of handset devices, a fourth radio wave intensity between the base device and the second handset or a fifth radio wave intensity between the first handset and the second handset, whichever is lower, is the maximum.

5. The wireless system according to claim 4.

6. a master unit provided inside a metal panel; a plurality of slave units provided inside the panel and configured to communicate with the master unit via wireless communication; a repeater provided inside the panel, communicating with the parent device and the child device via wireless communication and relaying communication between the parent device and the child device; A communication method in a wireless system comprising: a first handset among the plurality of handset devices communicates with the parent device via the repeater when a first radio wave intensity between the first handset and the parent device is lower than a second radio wave intensity between the first handset and the repeater and a third radio wave intensity between the parent device and the repeater, whichever is lower; Communication method.

7. a master unit provided inside a metal panel; a plurality of slave units provided inside the panel and configured to communicate with the master unit via wireless communication; A communication method for a wireless system comprising: a first handset whose radio wave strength between itself and the base unit is less than a threshold communicates with the base unit via a second handset different from the first handset; Communication method.

Images