Apparatus and method for scheduling data transmission

Abstract

An apparatus is provided. The apparatus includes at least one antenna, a plurality of buffer groups, and processing circuitry. Each buffer group includes a plurality of queue buffers, each queue buffer dedicated to a respective application category. The circuitry communicates with one or more stations via the at least one antenna. In response to the processing circuitry determining that a plurality of incoming frames or data packets are categorized as a same application category, the processing circuitry performs an intra-AC scheduling mechanism to determine a priority of data stored in the queue buffers in the same application category according to QoS (quality of service) requirements of each station in order to schedule a PPDU (physical layer protocol data unit) transmission to at least a portion of the stations.

Description

Technical Field

[0001] Embodiments of the present invention generally relate to traffic scheduling, and more particularly to an apparatus and method for delay-aware bandwidth scheduling (DABS) in wireless communications. Background Art

[0002] Wireless communication systems that use transmitters and receivers with one or more antennas are called multiple-input multiple-output (MIMO) systems. They provide higher peak data rates, spectral efficiency, and quality of service (QoS) by using multiple parallel data streams.

[0003] With technological advancements, stations (e.g., computing devices) can run a variety of applications, including VoIP (Voice over Internet Protocol), video conferencing, gaming, email, FTP (File Transfer Protocol), chat, peer-to-peer (P2P), and web applications. However, these applications have varying requirements for latency and buffer size. When multiple stations are connected to an access point, scheduling packets and frames for transmission to the stations becomes complex. Consequently, the access point may not be able to meet the station's requirements.

[0004] Therefore, there is a need for an apparatus and method for Delay Aware Bandwidth Scheduling (DABS) in wireless communications. Summary of the Invention

[0005] The following summary is illustrative only and is not intended to be limiting in any way. That is, the following overview is provided to introduce the concepts, key points, benefits, and advantages of the novel and non-obvious technologies described herein. Selected embodiments are further described in the detailed description below. Therefore, the following summary is not intended to identify essential features of the claimed subject matter nor is it intended to be used to determine the scope of the claimed subject matter.

[0006] In a first aspect, the present invention provides a device for scheduling data transmission, comprising: at least one antenna; a plurality of buffer groups, wherein each buffer group includes a plurality of queue buffers, and each queue buffer is dedicated to a corresponding application category; and a processing circuit, communicating with one or more sites through the at least one antenna; wherein the processing circuit is used to execute a scheduling mechanism for the same access category (for example, when it is determined that multiple incoming frames or packets are classified as the same application category) to determine the priority of data stored in the queue buffer of the same application category according to the quality of service QoS requirements of each site, so as to arrange the physical layer protocol data unit PPDU to be sent to at least a part of the one or more sites.

[0007] In some embodiments, the QoS requirement of each site is obtained from the incoming frame or packet using the Mirrored Stream Classification Service (MSCS) technique.

[0008] In some embodiments, the QoS requirement of each station is indicated in the Differentiated Services Code Point (DSCP) field or Type of Service (ToS) field of the incoming frame or packet.

[0009] In some embodiments, the QoS requirements of each site are obtained from incoming frames or packets using deep packet inspection (DPI) technology.

[0010] In some embodiments, the QoS requirement of each station is obtained from a request signal from each station to the device.

[0011] In some embodiments, the QoS requirements include delay bound, minimum required throughput, jitter tolerance, and loss rate.

[0012] In some embodiments, the delay bound has a tolerance within a predetermined percentage.

[0013] In some embodiments, the processing circuit is further configured to execute a scheduling mechanism for different access categories (e.g., when it is determined that multiple incoming frames or packets are classified into different application categories) to prioritize data stored in different queue buffers in a buffer group for different sites based on the QoS requirements of the different sites, thereby arranging the PPDU to be sent to the specific site.

[0014] In some embodiments, the processing circuit sends a trigger frame to the one or more stations to schedule transmission of uplink data of each station, and the processing circuit obtains the QoS requirement from the uplink data of each station.

[0015] In a second aspect, the present invention provides a method for scheduling data transmission, comprising: a device communicating with one or more sites via at least one antenna, wherein the device includes a plurality of buffer groups, each buffer group including a plurality of queue buffers, each queue buffer being dedicated to a respective application category; and executing a scheduling mechanism for the same access category (for example, when it is determined that a plurality of incoming frames or packets are classified as the same application category) to determine the priority of the data stored in the queue buffer of the same application category according to the quality of service QoS requirements of each site, so as to arrange for the physical layer protocol data unit PPDU to be sent to at least a portion of the one or more sites.

[0016] In some embodiments, the QoS requirements of each site are obtained from the incoming frames or packets using the Mirrored Stream Classification Service (MSCS) technology.

[0017] In some embodiments, the QoS requirement of each station is indicated in the Differentiated Services Code Point (DSCP) field or Type of Service (ToS) field of the incoming frame or packet.

[0018] In some embodiments, the QoS requirements of each site are obtained from incoming frames or packets using deep packet inspection (DPI) technology.

[0019] In some embodiments, the QoS requirement of each station is obtained from a request signal from each station to the device.

[0020] In some embodiments, the QoS requirements include delay bound, minimum required throughput, jitter tolerance, and loss rate.

[0021] In some embodiments, the delay bound has a tolerance within a predetermined percentage.

[0022] In some embodiments, the method further includes: the processing circuit is further used to execute a scheduling mechanism for different access categories (for example, when it is determined that multiple incoming frames or packets are classified into different application categories) to determine the priority of data stored in different queue buffers in the buffer group for different sites according to the QoS requirements of the different sites, so as to arrange the PPDU to be sent to the specific site.

[0023] In some embodiments, the method further includes: sending a trigger frame to the one or more sites to schedule transmission of uplink data of each site, and obtaining the QoS requirement from uplink data of each site.

[0024] In a third aspect, the present invention provides a method for scheduling data transmission, comprising: a device receiving a delay-aware bandwidth scheduling (DABS) quality of service (QoS) request signal from a site, wherein the DABS QoS request signal includes one or more QoS parameters; in response to the DABS QoS request signal, performing DABS on multiple incoming frames or packets received from the Internet according to the one or more QoS parameters to generate one or more scheduled physical layer protocol data units (PPDUs); and sending the scheduled PPDU to the site.

[0025] In some embodiments, the QoS requirements include delay bound, minimum required throughput, jitter tolerance, and loss rate.

[0026] Those skilled in the art will readily appreciate these and other objects of the present invention after reading the following detailed description of the preferred embodiments shown in the accompanying drawings. Detailed description will be given in the following embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention may be more fully understood by reading the subsequent detailed description and by referring to the examples given in the accompanying drawings, which (wherein like numbers represent like components) illustrate embodiments of the present invention. The accompanying drawings are included to provide a further understanding of the embodiments of the present disclosure, and the accompanying drawings are incorporated into and constitute a part of the embodiments of the present disclosure. The accompanying drawings illustrate implementation methods of the embodiments of the present disclosure and, together with the description, are used to explain the principles of the embodiments of the present disclosure. It will be understood that the drawings are not necessarily drawn to scale, as some components may be shown to be disproportionate to the dimensions in actual implementation to clearly illustrate the concepts of the embodiments of the present disclosure.

[0028] Figure 1 FIG. 4 is a schematic diagram of a wireless local area network (WLAN) according to an embodiment of the present invention.

[0029] Figure 2 is based on Figure 1 A block diagram of a wireless communication device according to an embodiment of the present invention.

[0030] Figure 3A FIG. 1 is a schematic diagram of OFDMA RU slicing in a DABS (Delay Aware Bandwidth Scheduling) mechanism performed by a wireless communication device according to an embodiment of the present invention.

[0031] Figure 3B FIG. 4 is a schematic diagram showing changes in RU groups over time according to an embodiment of the present invention.

[0032] Figure 4It is a schematic diagram of delivering QoS (quality-of-service) parameters in a DABS mechanism according to an embodiment of the present invention.

[0033] Figure 5 is a schematic diagram of a TSPEC (Traffic Specification) element according to an embodiment of the present invention.

[0034] 6A to 6D FIG. 1 is a schematic diagram of transmitting PPDU over time according to different embodiments of the present invention.

[0035] Figure 7A A schematic diagram of a WLAN with overlapping basic service sets (BSS) is shown according to an embodiment of the present invention.

[0036] Figure 7B according to Figure 7A The embodiment of FIG. 1 shows a timing diagram of Tx (transmit) and Rx (receive) operations of an access point in a WLAN without utilizing spatial reuse technology.

[0037] Figure 7C according to Figure 7A The embodiment shows a timing diagram of Tx and Rx operations of an access point in a WLAN when spatial reuse technology is used.

[0038] Figure 7D according to Figure 7A The embodiment shows a timing diagram of Tx and Rx operations of an access point in a WLAN when a DABS mechanism plus a spatial reuse technology is used.

[0039] Figure 7E FIG. 4 is a flowchart of a method for processing a new QoS request through DABS admission control according to an embodiment of the present invention.

[0040] In the following detailed description, for illustrative purposes, numerous specific details are set forth to enable those skilled in the art to more thoroughly understand the embodiments of the present invention. However, it is apparent that one or more embodiments may be practiced without these specific details, and different embodiments may be combined as needed, and the present invention should not be limited to the embodiments illustrated in the accompanying drawings. DETAILED DESCRIPTION

[0041] The following description is of preferred embodiments of the present invention and is intended only to illustrate the technical features of the present invention and is not intended to limit the scope of the invention. Certain terms are used throughout the specification and claims to refer to specific components. Those skilled in the art will appreciate that manufacturers may use different names for the same components. Therefore, this specification and claims do not distinguish components by name, but rather by functional differences. The terms "component," "system," and "device" used in this invention may refer to entities related to a computer, which may be hardware, software, or a combination of hardware and software. The terms "including" and "comprising" used in the following description and claims are open-ended and should be interpreted as meaning "including, but not limited to..." Furthermore, the term "coupled" refers to an indirect or direct electrical connection. Therefore, when a device is described as being coupled to another device, this means that the device may be directly electrically connected to the other device or indirectly electrically connected to the other device through other devices or connections.

[0042] Corresponding numerals and symbols in the various figures of the drawings generally refer to corresponding parts unless otherwise indicated. The drawings are drawn to clearly illustrate the relevant parts of the embodiments and are not necessarily drawn to scale.

[0043] As used herein, the terms "substantially" or "approximately" mean that a person skilled in the art is able to solve the desired technical problem and substantially achieve the desired technical effect within an acceptable range. For example, "approximately equal to" means that a certain deviation from "exactly equal to" is acceptable to a person skilled in the art without affecting the accuracy of the result.

[0044] Figure 1 is a schematic diagram of a wireless local area network (WLAN) according to an embodiment of the present invention.

[0045] The WLAN 100 may include a wireless-communication device 102 and one or more stations (STAs) 104, wherein the stations 104 may be all or part of the stations located within the range of the wireless-communication device 102, which may be connected to the Internet (or cloud network) 20 via the wireless-communication device. In one embodiment, the wireless-communication device 102 may be a wireless access point (WAP) or a central wireless router, and the stations 104 may include laptop computers, desktop computers, smart phones, tablet PCs, etc. Although Figure 1One wireless communication device 102 and three stations 104 are shown, but those skilled in the art will readily recognize that there can be any number of access points and any number of stations, and such number will be within the spirit and scope of the present invention. In other words, the present invention does not impose any limitation on the number.

[0046] In some embodiments, the wireless communication device 102 maintains the WLAN 100 by associating and authenticating new WLAN devices, such as the station 104, and by coordinating transmissions based on the time and bandwidth requests of the station 104. In one embodiment, the station 104 improves network efficiency by enabling the wireless communication device 102 to transmit data to multiple stations 104 simultaneously, utilizing advanced SU (single user) beamforming and multi-user (MU) MIMO (Multiple Input Multiple Output) technology.

[0047] Figure 2 is based on Figure 1 Please refer to the block diagram of the wireless communication device of the embodiment. Figure 1 and Figure 2 .

[0048] The wireless communication device 102 may include an integrated circuit 210, a processing circuit 220, a memory 230, a buffer memory 240, and at least one antenna. Here, antenna 250 (for example, two antennas, but the embodiment of the present invention does not impose any limitation on the number of antennas, which may be one or more) is taken as an example.

[0049] The antenna 250 can send and receive radio frequency (RF) signals. The integrated circuit 210 is coupled to the antenna 250, and the integrated circuit 210 may include one or more transceivers 211, which may receive RF signals from the antenna 250, convert them into baseband signals, and send the baseband signals to the processing circuit 220. The transceiver 211 may also convert the baseband signals from the processing circuit 220 into RF signals and send the RF signals to the antenna 250. In some embodiments, the integrated circuit 210 may support SU-MIMO (single-user multiple input multiple output) and MU-MIMO (multi-user multiple input multiple output) functions, but the present invention is not limited thereto. In some embodiments, the processing circuit 220 may be implemented by a central processing unit (CPU), a general-purpose processor, a digital signal processor (DSP), or a microcontroller, but the present invention is not limited thereto.

[0050] In some embodiments, the integrated circuit 210 may be a Wi-Fi chip, and the integrated circuit 210 and the processing circuit 220 may be implemented using a system-on-chip (SoC), but the present invention is not limited thereto. The memory 230 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 present invention is not limited thereto. In addition, the memory 230 stores instructions or firmware that can be executed by the processor 130 to control the operation of the wireless communication device 102.

[0051] The buffer memory 240 may be a volatile memory including multiple buffer sets 241, and each buffer set 241 may include queue buffers 2411 to 2414. For example, each of the queue buffers 2411 to 2414 may be a FIFO (first-in first-out) buffer for storing output packets of a corresponding application to be sent to each station 104.

[0052] Due to the instability of wireless links, the quality of real-time applications based on wireless local area networks (WLANs), such as VoIP and video streaming, can sometimes be poor. This is why it is necessary to prioritize network traffic by enabling Quality of Service (QoS). A Traffic Specification (TSPEC) is sent by a QoS-capable wireless client, requesting a certain amount of network traffic from the wireless communication device 102 (e.g., WAP) to represent the communication traffic stream (TS). The wireless communication device 102 then decides whether the request is acceptable and provides its decision to the client. Only after the WAP approves it can the client initiate high-priority communication. This prevents any type of collision or congestion on the wireless link, thereby maintaining good communication quality.

[0053] Since each station 104 may run different types of applications, such as VoIP (Voice over Internet Protocol) applications, gaming applications, video conferencing applications, TCP-based video streaming applications, email applications, FTP (File Transfer Protocol) applications, chat applications, peer-to-peer (P2P) applications, and web applications, these applications may be classified into four types based on delay requirements using deep packet inspection (DPI) technology implemented by processing circuitry 220. For example, processing circuitry 220 may analyze incoming traffic (i.e., incoming packets) and classify the incoming packets into different queues based on QoS parameters, such as delay bound, minimum required throughput in bits per second, jitter tolerance, and loss rate.

[0054] The IEEE 802.11e specification proposes two channel access mechanisms: Enhanced Distributed Channel Access (EDCA) and Hybrid Coordinator (HCF) Controlled Channel Access (HCCA), to provide QoS support for time-sensitive applications. EDCA improves upon the Distributed Coordination Function (DCF) by introducing four queues. For example, incoming frames or packets are classified into four AC (access category) classes (or admission control classes): AC_BK (background), AC_BE (best effort), AC_VI (video), and AC_VO (voice). Using different channel access parameters, these four classes have different priorities for accessing the channel, and these priorities provide strict priority scheduling. For example, the priorities of the four categories from low to high may be AC_BK, AC_BE, AC_VI, and AC_VO.

[0055] For example, users are very sensitive to acoustic noise or jitter during VoIP calls, so VoIP applications have the highest latency requirements (e.g., lowest tolerable latency). Therefore, packets from the Internet (or cloud network) for VoIP applications must be transmitted by wireless communication device 102 to site 104 in real time to achieve a good level of audio quality and intelligible conversations. For example, frames or packets of VoIP applications can be classified into the AC_VO category, which has the highest priority. In addition, real-time gaming applications and video conferencing applications have similarly high latency requirements (e.g., medium tolerable latency), and these applications can be classified into the same category AC_VI in IEEE 802.11e.

[0056] More specifically, the TSPEC element includes a set of parameters that define the characteristics and QoS expectations of a traffic flow in the context of a specific STA, and the parameter set can be used by the HC (Hybrid Coordinator) and (one or more) STAs that support QoS traffic. For example, the format of the TSPEC element can be as follows: Figure 5As shown (including the examples in the upper part and the examples in the lower part, it should be noted that Figure 5 is only an example of the format of the TSPEC element, but the present invention is not limited to this example), wherein, Figure 5 The lower half of the STA includes fields 502 to 518. For example, fields 502, 504, 506, 508, 510, 512, and 514 define the service start time, minimum data rate, mean data rate, peak data rate, burst size, delay bound, and minimum PHY rate, respectively. These fields 502 to 514 may express the QoS expectations requested by a specific STA.

[0057] For example, field 504 may define the minimum data rate in bits per second, which indicates the MPDU arrival rate. Field 512 may define the delay bound in microseconds, which indicates the queuing delay. Additionally, field 518 may define the medium time, which represents the requested usage time and can be calculated from the PHY rate and arrival rate.

[0058] However, as the number of video / voice applications grows, there are various QoS requirements for applications in the same category. For example, the traffic of gaming applications can be divided into TCP applications (such as massively multiplayer online role-playing games (MMORPGs)) and UDP applications (such as multiplayer online battle arenas (MOBAs)), where MMORPG applications may have a delay bound of around 50 to 100 milliseconds, while MOBA applications may have a delay bound of around 30 to 40 milliseconds. In addition, the traffic of video applications can be divided into UDP applications (such as video conferencing applications) and TCP applications (such as buffered video (streaming) applications), where video conferencing applications may have a delay bound of around 100ms, and the delay of buffered video applications may have a delay bound of around 200 to 500 milliseconds. In addition, with the advancement of technology, virtual reality (VR) applications and cloud gaming applications are becoming increasingly popular. However, these VR applications and cloud gaming applications are also very time-sensitive, but the current IEEE802.11 standard does not consider the specific QoS requirements of these applications.

[0059] Therefore, gaming and video applications have at least four QoS requirements. Therefore, the four AC categories defined in IEEE 802.11e are insufficient to support these corresponding QoS requirements. Furthermore, if a specific station does not support QoS, a traditional WAP that supports traditional IEEE 802.11e QoS features cannot support different QoS requirements.

[0060] In one embodiment, please refer to Figure 2The processing circuit 220 may include a traffic classifier 2201, a first scheduler 2202, and a second scheduler 2203. The traffic classifier 2201 may be configured to analyze incoming frames or packets from the Internet (or cloud network) using deep packet inspection (DPI) technology to obtain application-category information of the incoming frames or packets. The first scheduler 2202 may be considered a primary (priority) user set scheduler (PUSS) and is configured to perform QoS control, such as airtime fairness (ATF) and delay time in the time domain.

[0061] The second scheduler 2203 can be considered as a time-and-frequency STA scheduler (TFSS) and is configured to maximize user QoS requirements, such as throughput, delay, and associated jitter in both the time and frequency domains, thereby maximizing PPDU (physical-layer protocol data unit) efficiency or QoS support. The first scheduler 2202 and the second scheduler 2203 can form a two-level scheduler framework (e.g., a QoS scheduler) to provide time fairness (ATF) to each station 104 with low complexity and to provide delay guarantees for time-sensitive traffic in a wireless local area network (WLAN).

[0062] In one embodiment, the integrated circuit 210 may include a physical (PHY) layer and a MAC (Medium Access Control) layer, and the processing circuit 220 may include a firmware / driver layer, an application layer, and an OS (operating system) layer. Furthermore, there are several parameters in the upper / higher layers (e.g., the application layer or the OS layer) and the physical (PHY) layer. For example, the parameters in the higher layers may include airtime, bandwidth, delay time, and throughput, and the parameters in the physical layer may include channel information, queue status (e.g., the status of the queue buffers 2411 to 2414 in each buffer group 241), and a PHY factor.

[0063] For example, at time t, the first scheduler 2202 may obtain a parameter of airtime from the high-level information and calculate the priority of each station 104 (e.g., N stations). For example, the first scheduler 2202 may use a Sigmoid function to classify application requirements, where the Sigmoid function can be expressed as Equation (1):

[0064]

[0065] Here, x represents the QoS requirement. Therefore, the Sigmoid function can be used to describe the degree of QoS requirement or as a classifier in machine learning.

[0066] The second scheduler 2203 can obtain parameters of delay time and throughput from the high-layer information, and parameters of channel information, queue status, and PHY factor from the physical layer information. The second scheduler 2203 can then determine SU (single user) or OFDMA (orthogonal frequency division multiple access) allocation for each site 104. In some embodiments, the second scheduler 2203 can calculate a delay QoS function for each application, where the delay QoS function can be expressed as equation (2):

[0067]

[0068] Where D represents the delay bound and w represents the sensitivity of the delay performance factor.

[0069] For example, a resource unit (RU) is a unit in OFDMA terminology used in 802.11ax (Wi-Fi 6) WLAN to represent a set of 78.125KHz bandwidth subcarriers (tones) used in downlink (DL) transmissions and uplink (UL) transmissions. With OFDMA, different transmit powers can be applied to different RUs. There are up to 9 RUs for a 20MHz bandwidth, up to 18 RUs for a 40MHz bandwidth, and more for an 80 or 160MHz bandwidth. By utilizing OFDMA technology, the processing circuit 220 allows the subcarriers (tones) in the channel bandwidth to be grouped into smaller portions called "resource units". These individual RUs are assigned to different sites, and the RU-enabled wireless communication device 102 allows the sites 104 to access it simultaneously and efficiently.

[0070] In the IEEE 802.11ax (Wi-Fi 6) standard, several RUs are currently defined: 26-tone RU, 52-tone RU, 106-tone RU, 242-tone RU, 484-tone RU, 996-tone RU, and 2x996-tone RU. For example, for a basic 20 MHz bandwidth, nine 26-tone RUs can be used, but only four 52-tone RUs can be used. For example, when the wireless communication device 102 supports 52-tone RUs for its 20 MHz bandwidth, four users can transmit and / or receive with the wireless communication device 102 simultaneously. Each user uses 52 tones, but the total bandwidth for all users must be less than or equal to the full allocated bandwidth of the entire 20 MHz.

[0071] Figure 3A FIG. 1 is a schematic diagram of OFDMA RU slicing in a DABS (Delay Aware Bandwidth Scheduling) mechanism performed by a wireless communication device according to an embodiment of the present invention. Figure 3B Schematic diagram of the change of RU groups over time according to an embodiment of the present invention. Figure 2 and Figures 3A to 3B .

[0072] In one embodiment, when only one of the plurality of stations 104 is active, the wireless communication device 102 determines the inter-queue priorities of the applications running on the active station 104. For example, assuming Figure 2 The leftmost buffer group 241 is dedicated to the active site 104, and incoming packets or frames are sorted by processing circuit 220 into queue buffers 2411 through 2414, where queue buffers 2411 through 2414 can be viewed as AC_VO, AC_VI, AC_BE, and AC_BK buffers, respectively. Assuming a channel bandwidth of 80 MHz, if RUs of the same size are used, a maximum of eight 106-tone RUs, two 242-tone RUs, or one 484-tone RU can be used. However, larger RUs can be broken down into smaller RUs. For example, a combination of RUs could be one 484-tone RU, one 242-tone RU, two 106-tone RUs, and so on.

[0073] exist Figure 3AIn FIG, blocks 310 through 31N illustrate a dedicated buffer group for sites 1 through N, and each of blocks 310 through 31N includes four queue buffers, namely, VO, VI, BE, and BK (e.g., corresponding to AC_VO, AC_VI, AC_BE, and AC_BK, respectively). The first scheduler 2202 and the second scheduler 2203 may form a QoS scheduler 320 to determine SU or OFDMA allocations for RUs. In one scenario, the VO, VI, BE, and BK queue buffers for sites 1 through N may store incoming packets for VoIP applications, video conferencing applications, video streaming applications, and P2P applications. The QoS scheduler 320 may receive multiple QoS parameters related to higher layers and the physical layer, such as delay bounds, throughput requirements, loss rates, etc. Assuming that the VoIP application running on each site has the highest QoS requirement for delay time, the QoS scheduler 320 may assign the highest priority to the data stored in each VO queue buffer. In addition, the QoS scheduler 320 may also assign a medium priority to the data stored in each VI queue buffer and each BE queue buffer.

[0074] like Figure 3B As shown, in time interval T1, the QoS scheduler 320 may group…into one 484-tone RU (RU_484), one 242-tone RU (RU_242), and two 106-tone RUs (RU_106) into a HEPPDU (High-Efficiency Physical-layer Protocol Data Unit), where the data of the 484-tone RU, the 242-tone RU, and the 106-tone RU come from the VO, BE, and VI queue buffers of each site, respectively.

[0075] During time interval T2, the QoS scheduler 320 may encapsulate a 996-tone RU (RU_996) into a HE PPDU, where the data for the 996-tone RU comes from the VO queue buffer for each station. Because data for VoIP applications has the highest priority, the QoS scheduler may retrieve data from the VO queue buffer and encapsulate the retrieved data into a 996-tone RU during time interval T2. During time interval T3, the QoS scheduler 320 may encapsulate a 484-tone RU (RU_484), a 242-tone RU (RU_242), and two 106-tone RUs (RU_106) into a HE PPDU, where the data for the 484-tone RU, the 242-tone RU, and the 106-tone RU come from the BE, VO, and VI queue buffers, respectively, for each station.

[0076] Figure 4 Schematic diagram of transmitting QoS parameters in the DABS mechanism according to an embodiment of the present invention. Figure 2 and Figure 4 .

[0077] Assuming that the station 104 has a DABS function, when the DABS mode of the specific station 104 is triggered, the specific station 104 sends a DABS capability request signal to the wireless communication device 102 (step 402).

[0078] In response to the request signal from the specific site 104, the wireless communication device 102 sends a response signal to the specific site 104. Therefore, the specific site 104 knows that the wireless communication device 102 supports the DABS function. Then, the specific site 104 sends a DABS QoS request signal to the wireless communication device 102 (step 406). For example, the DABS QoS request signal may include one or more QoS parameters required by each application running on the specific site 104, where the QoS parameters may include, but are not limited to, a delay bound, a minimum throughput bits per second, and a loss rate.

[0079] In response to the DABS QoS request signal from the specific site 104, the wireless communication device 102 sends a DABS QoS response signal to the site 104 (step 408). Therefore, the specific site 104 knows that the wireless communication device 102 attempts to meet the QoS requirements indicated in the DABS QoS request signal. In some embodiments, the DABS QoS request signal and the DABS QoS response signal can be implemented through MSCS (Mirrored Stream Classification Service) and DSCP (Differentiated Service Code Point) mapping technology. For example, MSCS technology enables a client device to request that an access point apply specific QoS processing to downlink IP data flows using QoS mirroring. DSCP mapping technology aligns QoS processing across Wi-Fi and wired networks and enables network administrators to configure specific QoS policies. In some other embodiments, applications running on the specific site 104 can include their associated QoS parameters, and the processing circuit 220 can obtain the QoS parameters from the application and encapsulate the obtained QoS parameters into the DABS QoS request signal.

[0080] In step 410, the wireless communication device 102 keeps updating the QoS parameters. Thereafter, the station 104 sends the QoS data traffic to the wireless communication device 102 (step 412), and the wireless communication device 102 forwards the QoS data traffic to the Internet 20 (or cloud network) (step 414).

[0081] In response to the QoS data traffic, the Internet 20 (or cloud network) sends normal data to the wireless communication device 102, which is required by the application running on the station 104 (step 416). The normal data may include frames or packets from different applications, and the wireless communication device 102 may classify the frames or packets into queue buffers of different categories (e.g., AC_VO, AC_VI, AC_BE, and AC_BK) based on the application classification information. For example, the classification information may be obtained from the DSCP field or ToS (Type of Service) field of the incoming frame or packet. If the DSCP field or ToS field is not present in the incoming frame or packet, the wireless communication device 102 may analyze the incoming frame or packet from the Internet (or cloud network) using deep packet inspection (DPI) technology to obtain the application classification information of the incoming frame or packet.

[0082] Furthermore, it should be noted that multiple stations may send DABS QoS request signals to the wireless communication device 102, and the queue buffers in each buffer group for each station 104 may store corresponding frames or packets. At this point, the wireless communication device 102 also performs DABS on the data stored in the queue buffers and transmits the prepared (arranged) PPDU (e.g., HE PPDU) to the target station 104 (step 418).

[0083] Specifically, the QoS scheduler in the wireless communication device 102 may include an intra-AC scheduler (i.e., an intra-AC scheduler, which schedules under the same access class) and an inter-AC scheduler (i.e., an inter-AC scheduler, which schedules under different access classes). The intra-AC scheduler may be used in scenarios where applications / applications of the same application class (access class, AC) (e.g., buffered video and IPTV applications) are running on different stations 104, and incoming frames or packets are stored in the same queue buffer of a corresponding buffer group (e.g., AC_VI), or in other words, multiple incoming frames or packets are classified as belonging to the same application class. For example, for ease of explanation and understanding, using access class AC_VI as an example, in this example, incoming frames associated with a first station are stored in an AC_VI queue buffer of a first buffer group associated with the first station, incoming frames associated with a second station are stored in an AC_VI queue buffer of a second buffer group associated with the second station, and so on. Therefore, the same AC scheduler may prioritize data stored in queue buffers of the same application class (e.g., AC_VI) based on the QoS requirements of each station (e.g., determining the station priority based on the QoS requirements of each station, thereby prioritizing data stored in queue buffers of the same application class) to prepare a PPDU (e.g., a HE PPDU) for transmission to a target station. In one example, the PPDU may include data from multiple queue buffers of the same type (e.g., queue buffers of the same type in corresponding buffer groups of different stations, such as multiple queue buffers for AC_VI). In this example, the PPDU may be an MU PPDU. In another example, the PPDU may include data from the same type of queue buffer of a single station (eg, a queue buffer for AC_VI in a buffer group of a single station), in which example, the PPDU may be a SU PPDU.

[0084] Different AC schedulers may be used in the following scenarios: applications / applications of different application classes (access classes) are running on a specific site 104, and incoming frames or packets are stored in different queue buffers (e.g., AC_VO, AC_VI, AC_BE, and AC_BK) of the buffer group for the specific site 104, or in other words, multiple incoming frames or packets are classified into different application classes. The different AC schedulers may determine the priority of data stored in each queue buffer of the buffer group for the specific site 104 according to the QoS requirements of the specific site, and prepare a PPDU (e.g., HE PPDU) to be sent to the specific site 104. In one example, the PPDU (e.g., HE PPDU) may include data from one or more types of queue buffers (e.g., AC_VO, AC_VI, AC_BE, and AC_BK). Figure 3B In response to the specific station 104 ending the DABS mode, the specific station 104 sends a DABS QoS teardown request signal to the wireless communication device 102 (step 420).

[0085] More specifically, the same AC scheduler and different AC schedulers can provide additional bandwidth by sacrificing the STA's lower latency requirements (i.e., high tolerance for delay time). However, if the wireless communication device 102 provides insufficient bandwidth, the traditional scheduling mechanism will not be able to guarantee the latency requirements of STAs with high latency requirements. For example, if the wireless communication device 102 has 480 Mbps of available bandwidth and can support approximately 41 STAs, each STA has 10 Mbps of bandwidth. If the number of STAs increases from 41 to 50, these STAs still have the same latency requirements. Therefore, using the traditional scheduling mechanism, the latency for all STAs will be very high, and there will be no additional bandwidth available for newly connected STAs.

[0086] In one embodiment, admission control of the access class (AC) queue for each station is implemented in the wireless communication device 102 to ensure the QoS requirements of the allowed ACs. For example, the wireless communication device 102 may allocate a minimum bandwidth to a STA newly connected to the wireless communication device 102.

[0087] In one embodiment, the processing circuit 220 may send a trigger frame to the station 104 to schedule the transmission of uplink data from each station 104. For example, based on the instructions indicated in the trigger frame, each station 104 may transmit its own uplink packet (e.g., UL MU PPDU) using a different frequency within a specified time. In response to receiving the UL MU PPDU from each station 104, the processing circuit 220 may respond with an ACK (Acknowledgement) signal to each station 104.

[0088] 6A to 6D is a schematic diagram of transmitting PPDU over time according to different embodiments of the present invention. 6A to 6D .

[0089] In an example scenario, applications running on a specific site 104 may include gaming applications, video teleconferencing applications, VR applications, TV applications, IoT (Internet of Things) applications, and other applications (e.g., FTP, bitstream, web applications, etc.). The throughput and latency requirements of these applications are shown in Table 1:

[0090]

[0091] Table 1

[0092] refer to Figure 6A When wireless communication device 102 utilizes only the airtime fairness (ATF) round-robin method to prepare / prepare / arrange PPDUs, wireless communication device 102 may arrange the PPDU sequence over time into VR, other applications (labeled "Traffic"), TV, G, and VR, etc., because VR applications are the most time-sensitive applications compared to other applications. Therefore, due to the fairness of airtime for each application, the latency of the VR application is the time interval T11.

[0093] refer to Figure 6B When the wireless communication device 102 arranges / prepares PPDUs using the Time Fairness (ATF) round-robin method plus the DABS (Delay Aware Bandwidth Scheduling) method, the wireless communication device 102 may arrange the sequence of PPDUs into VR, Traffic, VR, G, VR, etc. over time, because VR applications are the most time-sensitive applications compared to other applications. Therefore, the delay time (delay) of VR applications may be the time interval T12, which is shorter than Figure 6A The time interval T11 is short.

[0094] refer to Figure 6C When the wireless communication device 102 arranges / prepares PPDUs using the ATF (Advanced Time Fairness) round-robin method plus the DABS (Delay Aware Bandwidth Scheduling) method plus the OFDMA method, the wireless communication device 102 may arrange the sequence of PPDUs over time as follows: Figure 6C As shown, the first PPDU is specifically used for VR applications, and the second PPDU is used for Traffic applications (marked as "Traffic" in the figure), VR applications, and video call applications (marked as "calll" in the figure). The third PPDU is used for TV applications (marked as "TV" in the figure) and game applications (marked as "G" in the figure), and the fourth PPDU is used for Traffic applications (marked as "T" in the figure), and the fifth PPDU is used for VR applications, TV applications, and IOT applications, respectively. It can be understood that the RUs of VR applications are arranged into the first PPDU, the second PPDU, and the fifth PPDU, which can further reduce the delay time of the VR application to the time interval T13, which is better than Figure 6B The time interval T12 is much shorter.

[0095] refer to Figure 6D When the wireless communication device 102 arranges / prepares PPDUs using the ATF (Advanced Time Fairness) round-robin method plus the DABS (Delay Aware Bandwidth Scheduling) method plus the OFDMA method plus the SR (Spatial Reuse) technology, the wireless communication device 102 may arrange the sequence of the PPDUs over time, such as Figure 6D As shown in the figure, the first PPDU is used for Traffic applications (labeled as "Traffic" in the figure), VR applications, and TV applications. The second PPDU is specifically used for VR applications, and the third PPDU is specifically used for game applications (labeled as "G" in the figure), the fourth PPDU is specifically used for VR applications and TV applications, and the fifth PPDU is specifically used for video call applications (labeled as "C" in the figure). It should be noted that the wireless communication device 102 can provide RUs of game applications and video call applications with additional opportunities to be arranged into OBSS PPDUs during OBSS (Overlapping Basic Service Set), thereby reducing the latency of time-sensitive game applications and video call applications, thereby improving user experience.

[0096] For example, Figure 7AA schematic diagram of an overlapping basic service set (OBSS) according to an embodiment of the present invention is shown. Assume that there are two basic service sets BSS1 and BSS2, and the basic service sets BSS1 and BSS2 use the same Wi-Fi channel (for example, CH=44). The basic service set BSS1 may include an access point BSS1-AP, and stations BSS1-STA1 and BSS1-STA2, wherein the access point BSS1-AP may be implemented by the wireless communication device 102. The basic service set BSS2 may include an access point BSS2-AP and a station BSS2-STA. From each other's perspective, each of the basic service sets BSS1 and BSS2 belongs to an OBSS. During the period when the access points BSS1-AP and BSS2-AP send (i.e., Tx) PPDUs to their respective stations BSS1-STA and BSS2-STA (where the two have overlapping time periods), the station BSS1-STA will be interfered with by BSS2.

[0097] If spatial reuse (SR) technology is not used, when the access point BSS2-AP in the basic service set BSS2 (which belongs to the OBSS with the basic service set BSS1) sends a PPDU to the station BSS2-STA1 in the time interval T1, the access point BSS1-AP cannot send a PPDU to the stations BSS1-STA1 and BSS1-STA2 in the basic service set BSS1, as shown in FIG. Figure 7B In addition, if spatial reuse technology is used, when the access point BSS2-AP in the basic service set BSS2 sends PPDU to the station BSS2-STA1 in the time intervals T2 and T3, the access point BSS1-AP can send PPDU to the stations BSS1-STA1 and BSS1-STA2 in the basic service set BSS1, as shown in FIG. Figure 7C In other words, the access point BSS1-AP can reuse the usage time by using the spatial reuse (SR) technology.

[0098] Please also refer to Figure 6D and Figure 7D If both the DABS technology and the spatial reuse (SR) technology are used, in the time interval T4, when the station BSS2-AP in the basic service set BSS2 sends a PPDU to the station BBS2-STA, the access point BSS1-AP in the basic service set BSS1 sends a PPDU to the station BBS2-STA through the DABS scheduler (for example, Figure 3AThe QoS scheduler 32n0 in the basic service set BSS1 can send a PPDU to the station BSS1-STA1. In addition, in time interval T5, when the station BSS2-AP in the basic service set BSS2 sends a PPDU to the station BSS2-STA, the access point BSS1-AP in the basic service set BSS1 can send a PPDU to the station BSS1-STA2 through the DABS scheduler.

[0099] Specifically, the access point BSS1-AP is able to determine whether to transmit PPDUs for applications with high latency requirements (i.e., requiring lower latency) within the SR reuse period of the OBSS. When the sites BSS1-STA1 and BSS1-STA2 are running gaming applications and video call applications, respectively, the DABS scheduler of the access point BSS1-AP decides to send a PPDU to the site BSS1-STA1 in time interval T4, and decides to send a PPDU to the site BSS1-STA2 in time interval T5. Accordingly, the gaming applications and video call applications running on the sites BSS1-STA1 and BSS1-STA2 can obtain additional opportunities to receive the required PPDUs during the OBSS period (i.e., time intervals T4 and T5), thereby reducing latency and improving user experience.

[0100] Figure 7E This is a flow chart of a method for processing a new QoS request through DABS admission control according to an embodiment of the present invention. Figure 1 and Figure 2 .

[0101] In step S710 , the wireless communication device 102 receives a new QoS request from a specific station. For example, the specific station supports QoS and is within the range of the wireless communication device 102 , and the specific station is attempting to connect to the wireless communication device 102 .

[0102] In step S712, the wireless communication device 102 calculates the usage time ReqAT of the new QoS request. In an exemplary embodiment, the usage time of the QoS request is between 0 and 1 second. For example, the wireless communication device 102 may calculate the first usage time ReqAT using equation (3):

[0103]

[0104] Wherein, DataRate represents the current data rate of the wireless communication device 102; PHYRate represents the data rate of the physical layer of the wireless communication device 102; and X represents a predetermined constant. In some embodiments, the value of X may be 80, but the present invention is not limited thereto.

[0105] In step S714, the wireless communication device 102 determines whether the idle airtime usage minus a first predetermined time (e.g., Y%, such as 10%) is less than the new QoS request usage time ReqAT. If the idle airtime usage minus the first predetermined time is less than the new QoS request usage time ReqAT, step S716 is executed. If the idle airtime usage minus the first predetermined time is greater than or equal to the new QoS request usage time ReqAT, it indicates that there is sufficient time for the new QoS request, and the wireless communication device 102 allows the specific station to join the WLAN 100 (step S718). For example, in an exemplary embodiment, taking 1s as a base unit, the idle time may be the idle time for 1s obtained after multiple measurements of 1s (e.g., 0.5s), and the first preset time (reserved margin time) may be the time corresponding to a preset percentage of 1s. For example, if the preset percentage is 10%, then the first preset time is 0.1s. Because the idle time minus the first preset time is 0.4s, if the usage time of the new QoS request is 0.2s, it is allowed to join the WLAN 100.

[0106] In step S716, the wireless communication device 102 determines whether the sum of multiple airtimes (AT) is less than a second preset time (e.g., Z%, such as 90%, indicating 10% idle time). If the sum of the multiple airtimes is less than the second preset time, it indicates that there is sufficient time for the new QoS request, and the wireless communication device 102 allows the specific station to join the WLAN 100 (step S718). If the sum of the multiple airtimes is greater than or equal to the second preset time (e.g., corresponding to a second preset percentage), step S720 is executed. Specifically, the multiple airtimes may include the new QoS request's airtime ReqAT, the airtime OBSS_AT used by other access points, the airtime QoS_AT used by high-priority applications, and the airtime BKAT used by low-priority applications. Therefore, the wireless communication device 102 calculates the total airtime of the new QoS request's airtime ReqAT, the airtime OBSS_AT, the airtime QoS_AT, and the airtime BKAT. If the total usage time is less than the second preset time or the second preset percentage, it indicates that there is enough time for the new QoS request, and the wireless communication device 102 allows the specific station to join the WLAN 100, otherwise it goes to step S720.

[0107] In step S720, the wireless communication device 102 determines whether the priority of the other QoS applications with poor link quality can be changed to a low priority. If it is determined that the other QoS applications with poor link quality can be changed to a low priority, step S722 is executed to change the priority of the other QoS applications with poor link quality to a low priority. If it is determined that the other QoS applications with poor link quality cannot be changed to a low priority, this indicates that all other QoS applications have high priority and good link quality, and the wireless communication device 102 cannot change any of the QoS applications to a low priority. In this case, the wireless communication device 102 rejects the new QoS request (step S724).

[0108] The embodiments described herein may be implemented in pure hardware, pure software, or a combination of hardware and software elements. The embodiments of the present invention may be implemented in software, including but not limited to application software, firmware, resident software, microcode, and the like.

[0109] The steps described herein may be implemented using any suitable controller or processor and a software application, which may be stored on any suitable memory location or computer readable medium. The software application provides instructions that enable the processor to cause the receiver to perform the functions described herein.

[0110] Furthermore, embodiments of the present invention take the form of a computer program product accessible from a computer-usable or computer-readable medium that provides program code for use by or in conjunction with a computer or any instruction execution system. For the purposes of this description, a computer-usable or computer-readable medium can be any means that can contain, store, communicate, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0111] The medium can be an electronic, magnetic, optical, electromagnetic, infrared, semiconductor system (or apparatus or device), or propagation medium. Examples of computer-readable media include semiconductor or solid-state memory, magnetic tape, removable computer disks, random access memory (RAM), read-only memory (ROM), hard disks, and optical disks. Current examples of optical disks include DVDs, compact disk-read-only memory (CD-ROM), and compact disk-read / write (CD-R / W).

[0112] The use of ordinal terms such as "first," "second," "third," etc. in the claims to modify claim elements does not in itself indicate any priority, precedence, or order of one claim element over another, or the temporal order of performing method actions, but serves solely as a marker to distinguish one claim element from another with the same name using ordinal numbers.

[0113] Although the present invention has been described by way of example and in terms of preferred embodiments, it should be understood that the invention is not limited to the disclosed embodiments. Rather, it is intended to cover various modifications and similar configurations (as will be apparent to those skilled in the art), for example, combinations or substitutions of different features from different embodiments. Accordingly, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar configurations.

Claims

1. An apparatus for scheduling data transmission, comprising: at least one antenna; a plurality of buffer groups, wherein different buffer groups in the plurality of buffer groups are respectively associated with different sites in the plurality of sites, each buffer group includes a plurality of queue buffers, and each queue buffer is dedicated to a corresponding application class; and processing circuitry to communicate with one or more stations via the at least one antenna; In which, when it is determined that multiple incoming frames or packets are classified into the same application category, the processing circuit is used to store the incoming frames or packets in the queue buffer for the same application category in the corresponding buffer group and execute the scheduling mechanism of the same access category to determine the priority of the data stored in the queue buffer for the same application category according to the quality of service QoS requirements of each site associated with the corresponding buffer group, so as to arrange the physical layer protocol data unit PPDU to be sent to at least part of the multiple sites.

2. The device according to claim 1, wherein The QoS requirement of each site is obtained from the incoming frame or packet using the mirrored flow classification service MSCS technology.

3. The device according to claim 2, wherein The QoS requirement of each station is indicated in the Differentiated Services Code Point (DSCP) field or Type of Service (ToS) field of the incoming frame or packet.

4. The device according to claim 1, wherein The QoS requirement of each site is obtained from the incoming frames or packets using deep packet inspection (DPI) technology.

5. The device according to claim 1, wherein The QoS requirement of each station is obtained from a request signal from each station to the device.

6. The device according to claim 1, wherein The QoS requirements include delay bound, minimum required throughput, jitter tolerance and loss rate.

7. The device according to claim 6, wherein The delay bound has a tolerance within a predetermined percentage.

8. The device according to claim 1, wherein When it is determined that multiple incoming frames or packets are classified into different application categories, the processing circuit is further used to execute a scheduling mechanism for different access categories to determine the priority of data stored in different queue buffers in the buffer group for different stations according to the QoS requirements of the different stations, so as to arrange the PPDU to be sent to a specific station.

9. The device according to claim 1, wherein The processing circuit sends a trigger frame to the one or more stations for scheduling transmission of uplink data of each station, and the processing circuit obtains the QoS requirement from the uplink data of each station.

10. A method for scheduling data transmission, comprising: an apparatus communicating with one or more stations via at least one antenna, wherein the apparatus comprises a plurality of buffer groups, different buffer groups in the plurality of buffer groups are respectively associated with different stations in the plurality of stations, each buffer group comprises a plurality of queue buffers, each queue buffer being dedicated to a respective application class; and When it is determined that multiple incoming frames or packets are classified into the same application category, the incoming frames or packets are stored in the queue buffer for the same application category in the corresponding buffer group and the scheduling mechanism of the same access category is executed to determine the priority of the data stored in the queue buffer of the same application category according to the quality of service QoS requirements of each site associated with the corresponding buffer group, so as to arrange the physical layer protocol data unit PPDU to be sent to at least part of the multiple sites.

11. The method according to claim 10, wherein The QoS requirements of each site are obtained from the incoming frames or packets using the mirrored flow classification service MSCS technology.

12. The method according to claim 11, wherein The QoS requirement of each station is indicated in the Differentiated Services Code Point (DSCP) field or Type of Service (ToS) field of the incoming frame or packet.

13. The method according to claim 10, wherein The QoS requirement of each site is obtained from the incoming frames or packets using deep packet inspection (DPI) technology.

14. The method according to claim 10, wherein The QoS requirement of each station is obtained from a request signal from each station to the device.

15. The method according to claim 10, wherein The QoS requirements include delay bound, minimum required throughput, jitter tolerance and loss rate.

16. The method according to claim 15, wherein The delay bound has a tolerance within a predetermined percentage.

17. The method according to claim 13, wherein The method further includes: When it is determined that multiple incoming frames or packets are classified into different application categories, the processing circuit is further used to execute a scheduling mechanism for different access categories to determine the priority of data stored in different queue buffers in the buffer group for different sites according to the QoS requirements of the different sites, so as to arrange the PPDU to be sent to a specific site.

18. The method according to claim 13, wherein The method further includes: sending a trigger frame to the one or more stations to schedule transmission of uplink data of each station, and The QoS requirement is obtained from the uplink data of each site.

19. A method for scheduling data transmission, comprising: The apparatus receives a delay-aware bandwidth scheduling (DABS) quality of service (QoS) request signal from a site, wherein the DABS QoS request signal includes one or more QoS parameters, the apparatus includes a plurality of buffer groups, different buffer groups in the plurality of buffer groups are respectively associated with different sites in the plurality of sites, each buffer group includes a plurality of queue buffers, and each queue buffer is dedicated to a corresponding application category; In response to the DABS QoS request signal, performing DABS on a plurality of incoming frames or packets received from the Internet according to the one or more QoS parameters to generate one or more scheduled physical layer protocol data units (PPDUs); and Sending the scheduled PPDU to the station; Executing the DABS includes: When it is determined that the multiple incoming frames or packets received are classified into the same application category, the incoming frames or packets are stored in the queue buffer for the same application category in the corresponding buffer group and the scheduling mechanism of the same access category is executed to determine the priority of the data stored in the queue buffer for the same application category according to the quality of service QoS requirements of each site associated with the corresponding buffer group, so as to arrange the physical layer protocol data unit PPDU to be sent to at least part of the multiple sites.

20. The method according to claim 19, wherein The QoS requirements include delay bound, minimum required throughput, jitter tolerance and loss rate.

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