The present invention relates to wireless-network communications, and, in particular, to a device and a method using spatial-reuse classification in a mesh network.
IEEE 802.11 is a set of media access control (MAC) and physical layer (PHY) specifications for implementing wireless local area network (WLAN) communication in the Wi-Fi (2.4, 3.6, 5, and 60 GHz) frequency bands. The 802.11 family consists of a series of half-duplex over-the-air modulation techniques that use the same basic protocol. The standards and amendments provide the basis for wireless network products using the Wi-Fi frequency bands. For example, IEEE 802.11ac is a wireless networking standard in the IEEE 802.11 family providing high-throughput WLANs on the 5 GHz band. Significant wider channel bandwidths (20 MHz, 40 MHz, 80 MHz, and 160 MHz) were proposed in the IEEE 802.11ac standard. The High Efficiency WLAN study group (HEW SG) is a study group within the IEEE 802.11 working group that will consider the improvement of spectrum efficiency to enhance the system throughput in high-density scenarios of wireless devices. Because of HEW SG, TGax (an IEEE task group) was formed and tasked to work on IEEE 802.11ax standard that will become a successor to IEEE 802.11ac. Recently, WLAN has seen exponential growth across organizations in many industries.
In IEEE 802.11ac WLAN systems, the transmitter of a BSS (basis service set) of certain bandwidth is allowed to transmit radio signals into the shared wireless medium depending on clear channel assessment (CCA) sensing and a deferral or backoff procedure for channel access contention. An enhanced distributed channel access protocol (EDCA) is used in IEEE 802.11ac as a channel contention procedure for wireless devices to gain access to the shared wireless medium, e.g., to obtain a transmitting opportunity (TXOP) for transmitting radio signals into the shared wireless medium. The basic assumption of EDCA is that a packet collision can occur if a device transmits signal under the channel busy condition when the received signal level is higher than the CCA level. This simple CSMA/CA with random back-off contention scheme and low-cost ad hoc deployment in an unlicensed spectrum have contributed to the rapid adoption of IEEE 802.11ac Wi-Fi systems.
BSS Coloring is a technique used to improve co-existence of overlapping BSSs (OBSS) and to allow spatial reuse (SR) within one channel. Wi-Fi 6 (IEEE 802.11ax) enables each AP radio to assign a value (from 1 to 63), known as the BSS color, to be included in the physical (PHY) header of all high-efficiency (HE) transmissions from devices in its BSS. With devices of each BSS transmitting a locally-unique color, a device can quickly and easily distinguish transmissions from its BSS or from devices in a neighboring BSS.
Today, Wi-Fi devices are over-populated. Dense deployment has led to significant issues such as interference, congestion, and low throughput. The spatial reuse technique introduced in the IEEE 802.11ax protocol may lead to a significant increase in the network throughput in some dense deployment scenarios because more simultaneous transmissions can happen in multiple overlapping BSSs (OBSSs). Although the spatial reuse feature in Wi-Fi 6 may help mitigate the co-channel interference in a mesh network, more usage of spatial reuse also introduces more collisions and interference into the mesh network. However, the spatial reuse feature in Wi-Fi 6 does not work in the mesh network. More specifically, the spatial reuse feature in Wi-Fi 6 only considers the AP-to-AP (access point to access point) RSSI (received signal strength indication) to adjust the power of the transmitter (i.e., Tx power), and it does not consider the SR SINR (signal-to-interference plus noise ratio) on an existing link between an access point and a station in the mesh network. This will cause a significant degradation on the SINR on the receiver of the existing link. In addition, internal traffic in the mesh network may have negative impact when some of the internal nodes are spatially reused by internal AP nodes in the mesh network. Moreover, there is no any mechanism in the Wi-Fi 6 protocol to coordinate SR behavior between AP nodes in the mesh network.
Accordingly, there is demand for a device and a method using spatial-reuse classification in a mesh network to solve the aforementioned problem.
An embodiment of the present invention provides a device. The device includes a transceiver and a processor. The transceiver connects the device to one or more first stations and an access point, and the access point is connected to one or more second stations. The processor is coupled to the transceiver and is configured to provide spatial reuse classification information for the access point to determine whether to apply spatial use in a first PPDU sent from the access point to one of the second stations.
Another embodiment of the present invention provides a method. The method includes the following steps: forming a mesh network using a first access point, a second access point, one or more first stations, and one or more second stations, wherein the first access point is connected to the one or more first stations and the second access point, and the second access point is connected to the one or more second stations; and utilizing the first access point to provide spatial reuse classification information for the second access point to determine whether to apply spatial use in a first PPDU sent from the second access point to one of the second stations.
Yet another embodiment of the present invention provides a device. The device includes a transceiver and a processor. The transceiver connects the device to one or more first stations and an access point, and the access point is connected to one or more second stations. The processor is coupled to the transceiver and is configured to classify a data transmission between the device and one of the first stations to inform the access point whether spatial reuse is allowed in the data transmission.
The present invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:
The following description is made for the purpose of illustrating the general principles of the disclosure and should not be taken in a limiting sense. The scope of the disclosure is best determined by reference to the appended claims.
The following description is presented to enable one of ordinary skill in the art to make and use the invention, and is provided in the context of a patent application and its requirements. Various modifications to the embodiments and the generic principles and features described herein will be readily apparent to those skilled in the art. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features described herein.
The mesh network 100 may include access points AP1, AP2 and AP3 and stations STA11, STA12, STA21 and STA31, wherein the access points AP1, AP2 and AP3 may be all or part of the access points that are located within the range of the mesh network 100. In addition, the access points AP1, AP2 and AP3 may be mesh AP nodes in the mesh network 100. In an embodiment, the access points AP1, AP2 and AP3 may include wireless routers, access points, laptops, desktop computers, smartphones, tablet PCs, etc. In some embodiments, the access point AP1 may be regarded as a controller device which is connected to a WAN (wide area network) port of a modem device (not shown in
More specifically, a mesh network allows nodes or access points to communicate directly with other nodes without being routed through a central switch point, e.g., a hub. In some embodiments, the access points AP1, AP2 and AP3 maintain the mesh network 100 by associating and authenticating new agent devices such as stations (STA), and by coordinating transmissions based on time and bandwidth requests by the agent device
As depicted in
The access points AP1 may include an integrated circuit 1101, processing circuitry 1102, a memory 1103, a buffer memory 1104, and at least one antenna 1105. The antennas 1105 may transmit and receive radio frequency (RF) signals. The integrated circuit 1101 is coupled to the antennas 1105, and the integrated circuit 1101 may include one or more transceivers 1106 which may receive RF signal from the antennas 1105, convert them to baseband signals, and send the baseband signals to the processing circuitry 1102. The transceivers 1106 may also convert the baseband signals from the processing circuitry 1102, convert them to RF signal, and send out the RF signals to antennas 1105. In some embodiments, the processing circuitry 1102 may be implemented by a central processing unit (CPU), a general-purpose processor, a digital signal processor (DSP), or a microcontroller, but the disclosure is not limited thereto.
In some embodiments, the integrated circuit 1101 may be a Wi-Fi chip, and the integrated circuit 1101 and the processing circuitry 1102 may be implemented by a system-on-chip (SoC), but the disclosure is not limited thereto. The memory 1103 may be a volatile memory or a non-volatile memory. For example, the volatile memory may be a static random access memory (SRAM) or a dynamic random access memory (DRAM), and the non-volatile memory may be a flash memory, a read-only memory (ROM), an erasable programmable read-only memory (EPROM), or an electrically erasable programmable read-only memory (EEPROM), but the disclosure is not limited thereto. In addition, the memory 1103 may store instructions or firmware that can be executed by the processing circuitry 1102 to control operations of the access point AP1. In some embodiments, components in the access points AP2 and AP3 may be similar to those in the access point AP1, and the details will not be repeated here.
In an embodiment, the access points AP1 may inform other mesh AP nodes (e.g., access point AP2) whether the current PPDU (physical layer protocol data unit) sent by the access point AP1 is allowed to be spatially reused or not using a particular field in the current PPDU. For example, when the current PPDU is an HE (High Efficiency) PPDU or an EHT (Extremely High-Throughput) PPDU, the current PPDU may include a “Reserved” field and a 4-bit “Spatial_Reuse” field in the PHY (physical layer) preamble. Thus, a particular value in the “Reserved” field or the “Spatial_Reuse” field can be designed to notify whether the mesh PPDU can be spatially reused.
As depicted in
At this time, the access point AP1 will modify the value of the “Spatial_Reuse” field in the PHY preamble of the PPDU 210 to 0xF to represent that the PPDU 210 for the existing link between access point AP1 and the station STA11 cannot be spatially reused. The access point AP2 can detect that the value of the “Spatial_Reuse” field in the PHY preamble of the PPDU 210 sent by the access point AP1 is 0xF without decoding the MAC payload of the PPDU 210. Therefore, the access point AP2 will not send another PPDU to its associated station STA21 for spatial reuse.
As depicted in
At this time, the access point AP1 will modify the value of the “Spatial_Reuse” field in the PHY preamble 221 of the PPDU 220 to 0x0 to represent that the PPDU 220 for the existing link between access point AP1 and the station STA12 can be spatially reused. The access point AP2 can detect that the value of the “Spatial_Reuse” field in the PHY preamble of the PPDU 220 sent by the access point AP1 is 0x0 without decoding the MAC payload of the PPDU 210. Therefore, the access point AP2 may then send another SR PPDU 230 to its associated station STA21 for spatial reuse.
In a similar manner, the “Reserved” field in the PHY preamble of the PPDU 210 or 220 can be used to indicate whether the PPDU 210 or 220 can be spatially reused by other access points. For example, the bit sequence combination of the “Reserved” field of the PPDU can be set using a undefined combination in the IEEE 802.11 standard to inform other access points whether spatial reuse on the PPDU is allowed or not.
In an embodiment, the mesh network 300 may include a controller 310 and an agent 320, where the controller 310 and agent 320 may be access points. The controller 310 is connected to the agent 320 through a Wi-Fi link 315. In addition, the agent 320 is connected to stations STA1, STA2, and STA3 that are assigned to the basic service set BSS1 with the same SSID of “Guest” and a BSS color 2, as shown in
The controller 310 may build a BSS-color black list according to the BSS color information (i.e., may be regarded as BSS group classification information) reported by the agent 320. When the value of a specific BSS color in the BSS-color black list is true, the controller 310 will not send a PPDU of the specific BSS color for spatial reuse. In this case, the agent 320 may report that the BSS color 2 is currently used, and thus the BSS-color black list built by the controller 310 can be illustrated by Table 1 as follows:
Each of the controller 310 and agent 320 in the mesh network 300 can create a duplicated BSS for each existing BSS with the same SSID (Service Set Identifier), the same password, and different BSS color or different BSSID (Basic Service Set Identifier). In this case, the agent 320 may duplicate the basic service set BSS1 with BSS color 2 to another basic service set BSS2 with BSS color 3. The agent 320 may steer the station STA2 with sufficient SR SINR to the basic service set BSS2.
Specifically, the agent 320 may build a table of the relationships between the SINR vs. Data Rate, which is shown in Table 2 as follows:
In Table 2, the data rate MCS7˜MCS11 can be referred to the IEEE 802.11 specification. The agent 320 may find that the station STA2 may have the highest SR SINR (e.g., 40 dB), the highest acceptable data rate (e.g., MCS11), and the highest common data rate (e.g., MCS11). In addition, the station STA2 may also have sufficient SINR after spatial reuse. Thus, the agent 320 may steer the station STA2 from the basic service set BSS1 to another basic service set BSS2, where the basic service set BSS2 has the same SSID as the basic service set BSS1, but its BSS color (e.g., BSS color 3) is different from the BSS color (e.g., BSS color 2) of the basic service set BSS1. Therefore, after the station STA2 has been steered to the basic service set BSS2, when the agent 320 sends a first PPDU to the station STA2, the controller 310 can detect that the BSS color indicated by the first PPDU may represent that the first PPDU can be spatially reused, and the controller 310 may then send a second PPDU to its associated station following the first PPDU, thereby achieving spatial reuse.
In an embodiment, the mesh network 400 may include a controller 410 and an agent 420, where the controller 410 and agent 420 may be access points as described in the embodiment of
The controller 410 may build a band SR black list according to the band information (e.g., band groups) reported by the agent 420. When the value of a specific band in the band SR black list is true, the controller 410 will not send a PPDU of the specific band for spatial reuse. In this case, the agent 420 may report that the Band 1 is currently used, and thus the band SR black list built by the controller 410 can be illustrated by Table 3 as follows:
The agent 420 may build a table of the relationships between the SINR vs. Data Rate, which is shown in Table 4 as follows:
In Table 4, the data rate MCS7˜MCS11 can be referred to the IEEE 802.11 specification. The agent 420 may find that the station STA2 may have the highest SR SINR (e.g., 40 dB), the highest acceptable data rate (e.g., MCS11), and the highest common data rate (e.g., MCS11). In addition, the station STA2 may also have sufficient SINR after spatial reuse. Thus, the agent 420 may steer the station STA2 from the Band 1 (i.e., a band group that does not allow spatial reuse) to Band 2 (i.e., another band group that allows spatial reuse). Therefore, after the station STA2 has been steered to Band 2, when the agent 420 sends a first PPDU to the station STA2 using band 2, the controller 410 can detect that the band information indicated by the first PPDU may represent that the first PPDU can be spatially reused, and the controller may then send a second PPDU to its associated station following the first PPDU, thereby achieving spatial reuse. Moreover, the agent 420 may keep its associated STAs having sufficient SINR in Band 1, and steer its associated STAs having insufficient SINR to Band 2.
In an embodiment, the mesh network 500 may include a controller 510 and an agent 520, where the controller 510 and agent 520 may be access points as described in the embodiment of
The controller 510 may build an AID SR black list according to the AID information reported by the agent 520. When the value of a specific AID in the AID SR black list is true, the controller 510 will not send a PPDU of the specific AID for spatial reuse. In this case, the agent 520 may report that the associated identifiers AID1 and AID3 are currently used, and thus the AID SR black list built by the controller 510 can be illustrated by Table 5 as follows:
It should be noted that the AID information only exist in the preamble of a VHT (Very High Throughput), HE (High Efficiency), and EHT (Extremely High Throughput) PPDU. The VHT PPDU is defined by the IEEE 802.11ac (Wi-Fi 5) standard, but the VHT PPDU merely includes partial AID which is not used in this embodiment. The HE PPDU is defined by the IEEE 802.11ax (Wi-Fi 6) standard. However, the AID information only exists in the HE-SIG-B field of the PPDU in the HE-MU (High Efficiency Multi-User) format. Therefore, when the AID classification method is applied to the HE stations, the agent 520 will send PPDUs in the MU format to its associated stations, even for a single user. With regard to the EHT PPDU, it can fully support the AID information. When all devices in the mesh network 500 support the IEEE 802.11be (Wi-Fi 7) standard, the controller 510 and the agent 520 can send EHT PPDUs to their associated stations.
In addition, the agent 520 may build a table of the relationships between the SINR vs. Data Rate, which is shown in Table 6 as follows:
In Table 6, the data rate MCS7˜MCS11 can be referred to the IEEE 802.11 specification. The agent 520 may find that the station STA2 may have the highest SR SINR (e.g., 40 dB), the highest acceptable data rate (e.g., MCS11), and the highest common data rate (e.g., MCS11). In addition, the station STA2 may also have sufficient SINR after spatial reuse. Thus, the controller 510 can monitor the AID in the preamble of the PPDU sent by the agent 520 to known which station this PPDU is sent to, and then determine whether to apply spatial reuse to another PPDU sent from the controller 510 to its associated stations without interfering existing link between the agent 520 and its associated station.
For example, when the agent 520 sends a first PPDU (e.g., may be in the HE or EHT format) to the station STA2, the controller 510 can detect that AID information indicated by the preamble of the first PPDU allows spatial reuse, and the controller 510 may then send a second PPDU to its associated station following the first PPDU, thereby achieving spatial reuse.
In view of the embodiments of
In
Each of device 610 and device 620 may be a part of an electronic apparatus, which may be a portable or mobile apparatus, a wearable apparatus, a wireless communication apparatus or a computing apparatus. For instance, each of device 610 and device 620 may be implemented in an access point (AP), a repeater, a smartphone, a smartwatch, a personal digital assistant, a digital camera, or a computing equipment such as a tablet computer, a laptop computer or a notebook computer. Each of device 610 and device 620 may also be a part of a machine type apparatus, which may be an IoT or NB-IoT apparatus such as an immobile or a stationary apparatus, a home apparatus, a wire communication apparatus or a computing apparatus. For instance, each of device 610 and device 620 may be implemented in a smart thermostat, a smart fridge, a smart door lock, a wireless speaker or a home control center. Alternatively, each of device 610 and device 620 may be implemented in the form of one or more integrated-circuit (IC) chips such as, for example and without limitation, one or more single-core processors, one or more multi-core processors, or one or more complex-instruction-set-computing (CISC) processors. Each of device 610 and device 620 may include at least some of those components shown in
In one aspect, each of processor 612 and processor 622 may be implemented in the form of one or more single-core processors, one or more multi-core processors, or one or more CISC processors. That is, even though a singular term “a processor” is used herein to refer to processor 612 and processor 622, each of processor 612 and processor 6522 may include multiple processors in some implementations and a single processor in other implementations in accordance with the present disclosure. In another aspect, each of processor 612 and processor 622 may be implemented in the form of hardware (and, optionally, firmware) with electronic components including, for example and without limitation, one or more transistors, one or more diodes, one or more capacitors, one or more resistors, one or more inductors, one or more memristors and/or one or more varactors that are configured and arranged to achieve specific purposes in accordance with the present disclosure. In other words, in at least some implementations, each of processor 612 and processor 622 is a special-purpose machine specifically designed, arranged and configured to perform specific tasks including implementation of performing cross-BSS non-triggered based spatial reuse in accordance with various implementations of the present disclosure.
In some implementations, device 610 may also include a transceiver 516 as a communication device coupled to processor 612 and configured to wirelessly transmit and receive data. In some implementations, device 610 may further include a memory 614 coupled to processor 612 and capable of being accessed by processor 612 and storing data therein. In some implementations, device 620 may also include a transceiver 626 as a communication device coupled to processor 622 and configured to wirelessly transmit and receive data. In some implementations, device 620 may further include a memory 624 coupled to processor 622 and capable of being accessed by processor 622 and storing data therein. Accordingly, device 610 and device 620 may wirelessly communicate with each other via transceiver 616 and transceiver 626, respectively.
To aid better understanding, the following description of the operations, functionalities and capabilities of each of device 610 and device 620 is provided in the context of device 610 acting as an access point (e.g., AP1, AP2, controller, and agent) and device 620 acting as a station (e.g., STA1, STA2, and STA3) of a mesh network (e.g., mesh network 200˜500).
Step S710: forming a mesh network using a first access point, a second access point, one or more first stations, and one or more second stations. For example, the first access point (e.g., controller) is connected to the one or more first stations and the second access point (e.g., agent). The second access point is connected to the one or more second stations (e.g., STA1-STA3).
Step S720: utilizing the first access point to provide spatial reuse classification information for the second access point to determine whether to apply spatial use in a first PPDU sent from the second access point to one of the second stations. For example, the spatial reuse classification information may be a particular field (e.g., “reserved” or “spatial_reuse” field of a PPDU, a BSS color information reported by the access point, band group classification information reported by the access point, or AID information reported by the access point.
Embodiments described herein can take the form of an entirely hardware implementation, an entirely software implementation, or an implementation containing both hardware and software elements. Embodiments may be implemented in software, which includes, but is not limited to, application software, firmware, resident software, microcode, etc.
The steps described herein may be implemented using any suitable controller or processor, and software application, which may be stored on any suitable storage location or computer-readable medium. The software application provides instructions that enable the processor to cause the receiver to perform the functions described herein.
Furthermore, embodiments may take the form of a computer program product accessible from a computer-usable or computer-readable medium providing program code for use by or in connection with a computer or any instruction execution system. For the purposes of this description, a computer-usable or computer-readable medium can be any device that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, device, or device.
The medium may be an electronic, magnetic, optical, electromagnetic, infrared, semiconductor system (or device or device), or a propagation medium. Examples of a computer-readable medium include a semiconductor or solid state memory, magnetic tape, a removable computer diskette, a random access memory (RAM), a read-only memory (ROM), a rigid magnetic disk, and an optical disk. Current examples of optical disks include DVD, compact disk-read-only memory (CD-ROM), and compact disk-read/write (CD-R/W).
While the invention has been described by way of example and in terms of the preferred embodiments, it should be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.
This application claims the benefits of U.S. Provisional Application No. 63/302,145 filed on Jan. 24, 2022, the entirety of which is incorporated by reference herein.
Number | Date | Country | |
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63302145 | Jan 2022 | US |