Wireless communication system, wireless communication method, and base station

Abstract

A wireless communication system (10) is provided with: a first wireless terminal (20) capable of performing communication by two methods, including a first communication method using a first frequency band and a second communication method using a second frequency band that is higher than the first frequency band; a second wireless terminal (30a) that supports communication by the first communication method and that does not support communication by the second communication method; and a multilink-supported base station 40a for accommodating the first wireless terminal (20) and the second wireless terminal (30a). A contention window value at the time of transmission in communication between the base station (40a) and the first wireless terminal (20) by the first communication method is set to a value that is larger than a prescribed value, which is a contention window value at the time of transmission in communication between the base station (40a) and the second wireless terminal (30a) by the first communication method.

Description

Technical Field

[0001] The present invention relates to a wireless communication system, a wireless communication method, and a base station.

Background Art

[0002] In recent wireless communication systems, it is important to increase wireless capacity in order to handle increasing mobile traffic. For example, in IEEE802.11be (Wireless LAN), a function of mounting a plurality of different wireless LAN interfaces on one device and establishing a plurality of transmission paths is adopted, and such a device is called a multi-link device (MLD) (see, for example, Non-Patent Document 1). Also, in IEEE802.11be, the use of the 6 GHz band is being considered.

Prior Art Documents

Non-Patent Documents

[0003]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When a multi-link device uses both an existing frequency band (e.g., 2.4 GHz band and 5 GHz band) and a new frequency band under consideration for use (e.g., 6 GHz band), competition occurs among existing multi-link-incompatible devices that can only use the existing frequency band. As a result, the communication speed of the existing devices decreases.

[0005] The present invention has been made in view of the above-described problems. An object of the present invention is to provide a wireless communication system, a wireless communication method, and a base station capable of preventing a decrease in the communication speed of an existing device when a multi-link device that uses both a low-frequency band and a high-frequency band coexists with an existing multi-link-incompatible device that uses the low-frequency band.

Means for Solving the Problems

[0006] A wireless communication system according to an embodiment of the present invention includes a first wireless terminal capable of communicating by both a first communication method using a first frequency band and a second communication method using a second frequency band higher than the first frequency band, a second wireless terminal corresponding to communication by the first communication method and not corresponding to communication by the second communication method, and a multi-link-compatible base station accommodating the first wireless terminal and the second wireless terminal. This wireless communication system sets the contention window value at the time of transmission in the communication between the base station and the first wireless terminal by the first communication method to a value larger than a predetermined value that is the contention window value at the time of transmission in the communication between the base station and the second wireless terminal by the first communication method When the BSS identifier of the received frame matches the own BSS, in the communication to be a value larger than a predetermined value which is the contention window value at the time of transmission in the communication between the base station and the second wireless terminal by the first communication method. and when the BSS identifier of the received frame in the communication between the base station and the first wireless terminal in the first communication method is different from the own BSS, set the contention window value at the time of transmission in the communication to the default value This is a feature.

[0007] In addition, a wireless communication method according to an embodiment of the present invention is a first wireless terminal capable of communicating by both a first communication method using a first frequency band and a second communication method using a second frequency band higher than the first frequency band, a second wireless terminal that is compatible with communication in the first communication method but not compatible with communication in the second communication method, and a multi-link compatible base station that accommodates the first wireless terminal and the second wireless terminal. This wireless communication method is for controlling When the BSS identifier of the received frame matches the own BSS, in the communication setting a contention window value at the time of transmission in communication between the base station and the first wireless terminal in the first communication method to a value larger than a predetermined value that is the contention window value at the time of transmission in communication between the base station and the second wireless terminal in the first communication method and when the BSS identifier of the received frame in the communication between the base station and the first wireless terminal in the first communication method is different from the own BSS, a step of setting the contention window value at the time of transmission in the communication to the default value; and is characterized by including this.

[0008] In addition, a base station according to an embodiment of the present invention is a multi-link compatible base station that accommodates a first wireless terminal capable of communicating by both a first communication method using a first frequency band and a second communication method using a second frequency band higher than the first frequency band, and a second wireless terminal that is compatible with communication in the first communication method but not compatible with communication in the second communication method. This base station When the BSS identifier of the received frame matches the own BSS, in the communication sets a contention window value at the time of transmission in communication with the first wireless terminal in the first communication method to a value larger than a predetermined value that is the contention window value at the time of transmission in communication with the second wireless terminal in the first communication method and when the BSS identifier of the received frame in the communication with the first wireless terminal in the first communication method is different from the own BSS, set the contention window value at the time of transmission in the communication to the default value and is characterized by this.

Advantages of the Invention

[0009] According to the present invention, when a multi-link device that uses both a low frequency band and a high frequency band coexists with an existing device that does not support multi-link and uses the low frequency band, it is possible to prevent the communication speed of the existing device from decreasing.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments will be described with reference to the accompanying drawings. Redundant descriptions will be appropriately simplified or omitted. Note that the present invention is not limited to the following embodiments. The present invention may include various modifications and combinations of the configurations disclosed by the following embodiments without departing from the gist thereof.

[0012] Embodiment 1. FIG. 1 is a diagram showing the configuration of a wireless communication system 10 according to Embodiment 1. As shown in FIG. 1, the wireless communication system 10 is connected to a network 100. The wireless communication system 10 includes, for example, a first wireless terminal 20, a second wireless terminal 30a, a third wireless terminal 30b, base stations 40a, 40b, control devices 50a, 50b, and a terminal device 110.

[0013] The control device 50a is connected to the network 100 and controls the base station 40a so that wireless communication between the base station 40a and the first wireless terminal 20 and wireless communication between the base station 40a and the second wireless terminal 30a are respectively performed.

[0014] The base station 40a is a multi-link compatible device, so-called a multi-link device. The base station 40a includes a device 80 that serves as an access point (AP) for communication using a first communication method (which may also be referred to as method 1 in this specification), and a device 90 that serves as an AP for a second communication method (which may also be referred to as method 2 in this specification). The base station 40a performs wireless communication with each of the first wireless terminal 20 and the second wireless terminal 30a in accordance with the control of the control device 50a.

[0015] Method 1 and method 2 are, for example, wireless communication methods compliant with the wireless LAN standard. Method 1 is, for example, a wireless communication method in the 5 GHz band in IEEE802.11. Method 2 is, for example, a wireless communication method in the 6 GHz band in IEEE802.11. In a multi-link device, wireless communication can be performed using method 1 and method 2 simultaneously.

[0016] Note that the base station 40a may be integrally configured with the control device 50a. That is, the base station 40a may include each function provided in the control device 50a.

[0017] The first wireless terminal 20 is a multi-link device. The first wireless terminal 20 is a multi-link compatible wireless terminal and serves as a station (STA) that communicates with the APs of the base station. The first wireless terminal 20 includes a device 60 corresponding to method 1 and a device 70 corresponding to method 2.

[0018] The device 60 corresponds to the communication method (method 1) of the device 80 of the base station 40a and performs wireless communication with the device 80. The device 70 corresponds to the communication method (method 2) of the device 90 of the base station 40a and performs wireless communication with the device 90.

[0019] The second wireless terminal 30a supports only method 1 out of method 1 and method 2. The second wireless terminal 30a does not support communication in method 2. The second wireless terminal 30a is a so-called existing device that does not support multi-link. The second wireless terminal 30a has a device 60 that supports method 1 and serves as a STA for performing wireless communication with the device 80 of the base station 40a.

[0020] The control device 50b is connected to the terminal device 110. The control device 50b controls the first wireless terminal 20 so that, for example, the first wireless terminal 20 and the base station 40a perform wireless communication. The control device 50b may have substantially the same configuration as the control device 50a. The terminal device 110 is a computer or the like that controls the control device 50b.

[0021] Note that the first wireless terminal 20 may be integrally configured with the control device 50b. That is, the first wireless terminal 20 may have each function provided by the control device 50b.

[0022] The base station 40b has a device 80 serving as an AP for method 1 and performs wireless communication with the third wireless terminal 30b. The third wireless terminal 30b is a wireless terminal having a device 60 that supports only method 1. The third wireless terminal 30b performs wireless communication in method 1 with the base station 40b.

[0023] That is, the wireless communication system 10 includes a first wireless terminal 20 capable of communicating by both a first communication method using a first frequency band (for example, 5 GHz) and a second communication method using a second frequency band (for example, 6 GHz) higher than the first frequency band, a second wireless terminal 30a that supports communication in the first communication method and does not support communication in the second communication method, and a multi-link compatible base station 40a that accommodates the first wireless terminal 20 and the second wireless terminal 30a. Note that the number of first wireless terminals 20 accommodated in the base station 40a may be one or more. Similarly, the number of second wireless terminals 30a accommodated in the base station 40a may be one or more.

[0024] Next, a specific configuration example of the base station 40a will be described. FIG. 2 is a diagram showing a specific configuration example of the base station 40a according to Embodiment 1. As shown in FIG. 2, the base station 40a includes, for example, a radio unit 41, a memory unit 42, an interface (I / F) unit 43, and a control unit 44.

[0025] The radio unit 41 includes the above-described devices 80 and 90. The radio unit 41 performs wireless communication with each of the wireless terminals accommodated in the base station 40a, that is, the first wireless terminal 20 and the second wireless terminal 30a.

[0026] The memory unit 42 stores information and the like received by the base station 40a via the radio unit 41 or the interface unit 43.

[0027] The interface unit 43 is a communication interface that communicates with the control device 50a.

[0028] The control unit 44 controls each unit constituting the base station 40a.

[0029] Next, a specific configuration example of the control device 50a will be described. FIG. 3 is a diagram showing a specific configuration example of the control device 50a that controls the base station 40a according to Embodiment 1. As shown in FIG. 3, the control device 50a includes, for example, a memory unit 51, an interface (I / F) unit 52, an interface (I / F) unit 53, and a control unit 56.

[0030] The memory unit 51 is a storage device that stores data within the control device 50a.

[0031] The interface unit 52 is a communication interface that communicates with the base station 40a. The interface unit 53 is a communication interface that communicates with the network 100.

[0032] The control unit 56 controls each part constituting the control device 50a to control the wireless communication by the base station 40a which is a multi-link device. In the present embodiment, the control unit 56 controls the contention window (CW) value at the time of transmission in the communication between the base station 40a and the first wireless terminal 20.

[0033] For example, the contention window value at the time of transmission in the communication between the base station 40a and the second wireless terminal 30a in method 1 is set to a default value. For example, the contention window value at the time of transmission in the communication between the base station 40b and the third wireless terminal 30b is also set to this default value. The control unit 56 sets the contention window value at the time of transmission in the communication between the base station 40a and the first wireless terminal 20 in method 1 to a value larger than the above default value.

[0034] The control unit 56 has a function of determining whether the communication by the base station 40a in method 1 is MLD communication when the base station 40a performs communication in method 1 by the device 80, for example. When the control unit 56 determines that the communication by the base station 40a in method 1 is MLD communication, that is, when the communication target of the base station 40a is the first wireless terminal 20, the control unit 56 sets the contention window value to a value larger than the default value. When the control unit 56 determines that the communication by the base station 40a in method 1 is not MLD communication, that is, when the communication target of the base station 40a is the second wireless terminal 30a, the control unit 56 sets the contention window value to the default value.

[0035] Note that each function of the control device 50a may be partially or entirely configured by hardware such as a PLD (Programmable Logic Device) or an FPGA (Field Programmable Gate Array), or may be configured as a program executed by a processor such as a CPU.

[0036] For example, the control device 50a can be realized using a computer and a program, and it is also possible to record the program on a storage medium or provide it through a network.

[0037] FIG. 4 is a diagram showing a hardware configuration example of a control device 50a that controls the base station 40a according to Embodiment 1. As shown in FIG. 4, the control device 50a includes an input unit 500, an output unit 510, a communication unit 520, a CPU 530, a memory 540, and an HDD 550, which are connected via a bus 560 and have functions as a computer. Further, the control device 50a is configured to be able to input and output data to and from a computer-readable storage medium 570.

[0038] The input unit 500 is, for example, a keyboard and a mouse. The output unit 510 is, for example, a display device such as a display. The communication unit 520 is, for example, a network interface.

[0039] The CPU 530 controls each part constituting the control device 50a and performs predetermined processing and the like. The memory 540 and the HDD 550 are storage units that store data and the like.

[0040] The storage medium 570 is capable of storing a program and the like for causing the control device 50a to execute its functions. Note that the architecture constituting the control device 50a is not limited to the example shown in FIG. 4.

[0041] As described above, the control device 50b may have substantially the same configuration as the control device 50a. For example, the control device 50b may set the contention window value at the time of transmission in the communication between the base station 40a and the first wireless terminal 20 in method 1 to a value larger than the default value. When the communication target of the first wireless terminal 20 is the base station 40b or the like and the communication is not MLD communication, the control device 50b may set the contention window value to the default value.

[0042] Next, with reference to the flowchart, the operation and modification examples of the wireless communication system 10 will be described. FIG. 5 is a flowchart showing an operation example of the wireless communication system 10 according to Embodiment 1.

[0043] The flowchart of FIG. 5 shows an example of the control operation of the contention window value when the base station 40a communicates with the device 80 in method 1. First, it is determined whether the communication is MLD communication (step S101). If it is not MLD communication, the contention window value is set to a default value (step S102).

[0044] Here, when the communication between the base station 40a and the device 80 in method 1 is MLD communication, for example, using the SR (Spatial Reuse) function, it may be detected that there is no impact on the existing first frequency band during multi-link. That is, it may be detected and determined whether the BSS identifier (BSS color) of the received frame in the communication between the base station 40a and the first wireless terminal 20 in method 1 matches the own BSS (step S103).

[0045] If the BSS identifier of the received frame is different from the own BSS, since there is no impact on the existing first frequency band, the contention window value may be set to the default value (step S102). If the BSS identifier of the received frame matches the own BSS, since there is an impact on the existing first frequency band, the contention window value is set to be larger than the default value (step S104).

[0046] The SR function is realized, for example, by the SR control unit 55 provided in the control device 50a. The SR control unit 55 functions as a determination unit having, for example, the determination function of step S103 described above. The control unit 56 controls the value of the contention window value according to the determination result of the SR control unit 55 functioning as a determination unit.

[0047] As described above, the wireless communication system 10 according to this embodiment is configured to set the contention window value at the time of transmission in the communication between the base station 40a and the first wireless terminal 20 using the first communication method to a value larger than the default value, which is the contention window value at the time of transmission in the communication between the base station 40a and the second wireless terminal 30a using the first communication method. The waiting time at the time of transmission in wireless communication is determined according to the contention window value. By increasing the contention window value at the time of transmission in the communication between the base station 40a and the first wireless terminal 20 using the first communication method, the waiting time at the time of transmission increases, and it becomes relatively difficult to obtain a transmission opportunity. On the other hand, in the communication between the base station 40a and the second wireless terminal 30a using the first communication method, it becomes relatively easy to obtain a transmission opportunity.

[0048] In the wireless communication system 10 according to this embodiment, in the first frequency band, the second wireless terminal 30a, which is an existing device that does not support multi-link, can obtain the transmission right preferentially over the first wireless terminal 20, which is a multi-link device. Thereby, it becomes possible to improve the total throughput of the second wireless terminal 30a, which is an existing device that does not support multi-link. According to this embodiment, when a multi-link device that uses both a low frequency band and a high frequency band coexists with an existing device that does not support multi-link and uses the low frequency band, it is possible to prevent the communication speed of the existing device from decreasing. Note that each function of the wireless communication system 10 and each component such as the base station 40a that constitutes the wireless communication system 10 can also be realized as a wireless communication method including each function as a process.

Explanation of Reference Numerals

[0049] 10 Wireless communication system 20 First wireless terminal 30a Second wireless terminal 30b Third wireless terminal 40a Base station 40b Base station 41 Wireless section 42 Storage section 43 Interface section 44 Control section Control device 50a Control device 50b Memory unit 51 Interface unit 52 Interface unit 53 SR control unit 55 Control unit 56 Device 60 Device 70 Device 80 Device 90 Network 100 Terminal device 110 Input unit 500 Output unit 510 Communication unit 520 CPU 530 Memory 540 HDD 550 Bus 560 Memory medium 570

Claims

1. A first wireless terminal capable of communicating by both a first communication method using a first frequency band and a second communication method using a second frequency band higher than the first frequency band, a second wireless terminal that is compatible with communication by the first communication method and incompatible with communication by the second communication method, and a multi-link compatible base station that houses the first wireless terminal and the second wireless terminal, In a wireless communication system comprising: When the BSS identifier of the received frame in the communication between the base station and the first wireless terminal by the first communication method matches the own BSS, the contention window value at the time of transmission in the communication is set to a value larger than a default value that is the contention window value at the time of transmission in the communication between the base station and the second wireless terminal by the first communication method, A wireless communication system, characterized in that when the BSS identifier of the received frame in the communication between the base station and the first wireless terminal by the first communication method is different from the own BSS, the contention window value at the time of transmission in the communication is set to the default value.

2. The wireless communication system according to claim 1, characterized in that the first communication method and the second communication method are wireless communication methods conforming to the standards of a wireless LAN.

3. A first wireless terminal capable of communicating by both a first communication method using a first frequency band and a second communication method using a second frequency band higher than the first frequency band, a second wireless terminal that is compatible with communication by the first communication method and incompatible with communication by the second communication method, and a multi-link compatible base station that houses the first wireless terminal and the second wireless terminal, In a wireless communication method for controlling: When the BSS identifier of the received frame in the communication between the base station and the first wireless terminal by the first communication method matches the own BSS, a step of setting the contention window value at the time of transmission in the communication to a value larger than a default value that is the contention window value at the time of transmission in the communication between the base station and the second wireless terminal by the first communication method; When the BSS identifier of the received frame in the communication between the base station and the first wireless terminal by the first communication method is different from the own BSS, a step of setting the contention window value at the time of transmission in the communication to the default value; A wireless communication method, characterized by including the above.

4. The wireless communication method according to claim 3, characterized in that the first communication method and the second communication method are wireless communication methods compliant with the wireless LAN standard.

5. A first wireless terminal capable of communicating by both a first communication method using a first frequency band and a second communication method using a second frequency band higher than the first frequency band, and a second wireless terminal corresponding to communication by the first communication method and not corresponding to communication by the second communication method, in a multi-link compatible base station accommodating the same, when the BSS identifier of the received frame in the communication with the first wireless terminal by the first communication method matches the own BSS, the contention window value at the time of transmission in the communication is set to a value larger than the default value which is the contention window value at the time of transmission in the communication with the second wireless terminal by the first communication method, a base station characterized in that when the BSS identifier of the received frame in the communication with the first wireless terminal by the first communication method is different from the own BSS, the contention window value at the time of transmission in the communication is set to the default value.

6. The base station according to claim 5, characterized in that the first communication method and the second communication method are wireless communication methods compliant with the wireless LAN standard.

Images