Protocol Data Unit (PPDU) Transmission Method and Apparatus
By allocating channels to SST stations through MU-RTS frames with specific indication information and scrambling code initialization, the method addresses inefficiencies in channel protection for secondary channels, reducing interference and enhancing network efficiency in wireless local area networks.
Patent Information
- Application Number
- JP2023531015
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Priority Date
- 2020-12-18
- Filing Date
- 2021-11-18
- Publication Date
- 2025-08-26
- Estimated Expiration
- 2041-11-18
AI Technical Summary
In wireless local area networks, stations operating on secondary channels (SST) cannot fully utilize channel resources due to the absence of the primary 20 MHz channel in their operating channel, leading to inefficiencies in channel protection mechanisms like RTS/CTS and MU-RTS/CTS, resulting in interference during data reception and transmission.
A method and apparatus for allocating channels to SST stations by transmitting MU-RTS frames with indication information to specify target channels for CTS frames, using bit sequences to distinguish channels and ensure compatibility with MU-RTS/CTS mechanisms, and employing scrambling code initialization values to avoid conflicts among multiple CTS frames.
This approach reduces interference and enhances channel utilization by allowing SST stations to reserve channels effectively, ensuring simultaneous data transmission and reception without conflicts, thereby improving network efficiency.
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Abstract
Description
[Technical Field]
[0001] This application relates to the field of communication technology, and in particular to a protocol data unit (PPDU) transmission method and apparatus.
[0002] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to Chinese Patent Application No. 202011511846.3, filed with the State Intellectual Property Office of the People's Republic of China on December 18, 2020, and entitled "PROTOCOL DATA UNIT PPDU TRANSMISSION METHOD AND APPARATUS," which is incorporated herein by reference in its entirety. [Background technology]
[0003] Currently, the basic framework commonly used in wireless access standards is that a wireless access point (AP) accesses the Internet in a wired or wireless manner. In addition, the AP is associated with multiple stations, and uplink and downlink communications can be conducted between the associated stations. The channel for communications between the AP and the multiple associated stations can support a maximum bandwidth of 320 MHz. Each associated station can communicate with the AP on a designated channel.
[0004] In wireless local area networks, since hidden nodes are common, channels can be reserved for associated stations in a request to send (RTS) / clear to send (CTS) interactive manner. RTS and CTS frames can be transmitted in a non-high throughput (Non-HT) duplicated manner in bandwidths greater than 20 MHz. Currently, the bandwidths that can be used to transmit CTS frames are one of 20 MHz, 40 MHz, 80 MHz, 160 (80 + 80) MHz, and 320 MHz, and the occupied channels are the primary 20 MHz channel, primary 40 MHz channel, primary 80 MHz channel, primary 160 MHz channel, and 320 MHz channel, respectively.
[0005] To improve the efficiency of channel protection, a multi-user request to transmit (MU-RTS) / CTS interaction mechanism is introduced. The principle of the MU-RTS / CTS interaction mechanism is that the AP broadcasts an MU-RTS frame. The MU-RTS frame carries the identifiers of multiple receiving stations and specifies, for each receiving station, information about the bandwidth for replying to a CTS. After the MU-RTS frame ends, each receiving station replies to and transmits a CTS frame in the specified bandwidth after a short inter-frame space (SIFS) time. The specified bandwidth here is a 20 MHz channel, a 40 MHz channel, an 80 MHz channel, or a 160 MHz channel, including the primary 20 MHz subchannel.
[0006] In addition, to fully utilize channel resources, a subchannel selective transmission (SST) mechanism is used to schedule 20 MHz or 80 MHz stations to the secondary channel, where they can transmit and receive data. The working principle of the subchannel selective transmission mechanism is that an AP can schedule a station to receive downlink data on a designated secondary channel or to transmit uplink data via a schedule within an optimized target wake-up time (TWT). A station scheduled to operate on a secondary channel may be referred to as an SST station.
[0007] However, the operating channel of an SST station does not include the primary 20 MHz channel, and the channel occupied for transmitting a CTS must include the primary 20 MHz channel, i.e., the station SST cannot complete RTS / CTS or MU-RTS / CTS channel protection. Summary of the Invention
[0008] This application provides a protocol data unit (PPDU) transmission method and apparatus for allocating a channel to an SST STA for transmitting a CTS frame.
[0009] According to a first aspect, a MU-RTS frame transmission method is provided. The method can be performed by a first device provided in an embodiment of this application. The first device can be an AP or a chip implementing functions similar to those of an AP. In the method, the first device can transmit a MU-RTS frame. The MU-RTS frame can include indication information indicating a first channel. Here, the first channel is the first channel on which a second device transmits a CTS frame. The first channel includes a target channel of the second device. The target channel can be a 20 MHz subchannel within the operating channel of the SST STA. Alternatively, the target channel can be any 20 MHz subchannel other than the primary 20 MHz channel.
[0010] Based on the above solution, the AP can indicate to the SST STA the channel for replying to the CTS frame based on the indication information, so that the SST STA can also reserve the channel according to the MU-RTS / CTS mechanism, thereby reducing interference during data reception and transmission.
[0011] In a possible implementation, the indication information may include a first bit sequence, which indicates a first channel. Optionally, the indication information may further include a second bit sequence, which has a value of 1 or a reserved state.
[0012] Based on the above solution, the AP can indicate to the SST STA the channel for replying to the CTS frame based on the first bit sequence in the MU-RTS frame. In addition, since the operating channel of the SST STA does not include the primary 20 MHz channel, the value of the second bit sequence is set to 1 or in a reserved state to distinguish it from the STA whose operating channel includes the primary 20 MHz channel.
[0013] According to a second aspect, a CTS frame transmission method is provided. The method can be performed by a second device provided in an embodiment of this application. The second device can be an SST STA or a chip implementing functions similar to those of an SST STA. In the method, the second device can receive an MU-RTS frame. The MU-RTS frame can include indication information. The indication information here can indicate a first channel. The second device can transmit a CTS frame on the first channel. The first channel includes a target channel of the second device.
[0014] Based on the above solution, the AP can indicate to the SST STA the channel for replying to the CTS frame based on the indication information, so that the SST STA can also reserve the channel according to the MU-RTS / CTS mechanism, thereby reducing interference during data reception and transmission.
[0015] In a possible implementation, the indication information may include a first bit sequence, which indicates a first channel. Optionally, the indication information may further include a second bit sequence, which has a value of 1 or a reserved state.
[0016] Based on the above solution, the AP can indicate to the SST STA the channel for replying to the CTS frame based on the first bit sequence in the MU-RTS frame. In addition, since the operating channel of the SST STA does not include the primary 20 MHz channel, the value of the second bit sequence is set to 1 or in a reserved state to distinguish it from the STA whose operating channel includes the primary 20 MHz channel.
[0017] According to a third aspect, a protocol data unit (PPDU) transmission method is provided. The method can be performed by a first device provided in an embodiment of this application. The first device can be an AP or a chip implementing functions similar to those of an AP. In this method, the first device can transmit a first data unit. The first data unit can include at least a second data unit and a third data unit. The second data unit is used to carry a first MU-RTS frame. The third data unit is used to carry a second MU-RTS frame. The first MU-RTS frame and the second MU-RTS frame use the same scrambling code initialization value.
[0018] Based on the above solution, the AP can use multiple MU-RTS frames to indicate to multiple STAs the channels to reply to the CTS frame. The AP can indicate to the first MU-RTS frame and the second MU-RTS frame to use the same scrambling code initialization value. This can avoid conflicts between different CTS frames.
[0019] In a possible implementation, the first MU-RTS frame indicates a first channel on which a second device transmits a clear to send CTS frame. The second MU-RTS frame indicates a second channel on which a third device transmits a CTS frame. When the bandwidth of the first channel partially or completely overlaps with the bandwidth of the second channel, the first MU-RTS frame and the second MU-RTS frame use the same scrambling code initialization value.
[0020] Based on the above solution, when the bandwidths of the channels on which multiple STAs reply to a CTS frame overlap, the AP may allow the MU-RTS frames indicating the overlapping channels to use the same scrambling code initialization value, which can avoid conflicts between different CTS frames.
[0021] In a possible implementation, the first data unit may include multiple data units, each of which is used to carry an MU-RTS frame, and all of the MU-RTS frames have the same scrambling code initialization value. The second data unit and the third data unit are two of the multiple data units.
[0022] Based on the above solution, the AP may allow all scrambling code initialization values of multiple transmitted MU-RTS frames to be the same, which can avoid conflicts between different CTS frames.
[0023] In a possible implementation, the first MU-RTS frame and the second MU-RTS frame may each include a first bit sequence. The first bit sequence may indicate the bandwidth of the first data unit. Alternatively, the first MU-RTS frame may include a second bit sequence. The second bit sequence may indicate the bandwidth of the second data unit. The second MU-RTS frame may include a third bit sequence. The third bit sequence may indicate the bandwidth of the third data unit.
[0024] Based on the above solution, the AP can indicate the bandwidth of the PPDU carrying the MU-RTS frame based on a bit sequence within the MU-RTS frame, or can indicate the bandwidth for carrying multiple MU-RTS frames based on a bit sequence.
[0025] According to a fourth aspect, a method for transmitting a request-to-send (RTS) frame is provided. The method can be performed by a first device provided in an embodiment of this application. The first device can be an AP or a chip implementing functions similar to those of an AP. In the method, the first device can separately transmit RTS frames on at least two channels. The first device can receive CTS frames having the same frame length on at least two channels.
[0026] Based on the above solution, the AP can use multiple RTS frames to indicate to multiple STAs the channels for replying to the CTS frame and the frame lengths of the multiple CTS frames received by the AP. In this way, multiple STAs can simultaneously transmit data within the SIFS time after the CTS ends. This avoids the case where the channel is occupied by a third party due to the channel idle time longer than the SIFS on some subchannels.
[0027] In a possible implementation, the frame length of all RTS frames may be the same.
[0028] Based on the above solution, the AP can control the frame length of each transmitted RTS frame, so that the frame lengths of multiple RTS frames are the same and the transmission durations can be adjusted.
[0029] In a possible implementation, the first transmission rate of all RTS frames may be the same. Alternatively, the first transmission rate of each RTS frame may be used to determine the same second transmission rate. The second transmission rate is the main rate at which the second device transmits CTS frames.
[0030] Based on the above solution, the AP can control the main rate of the CTS frame by controlling the rate of the RTS frame, and control the frame lengths of the CTS frames sent by multiple STAs to be the same.
[0031] According to a fifth aspect, a method for transmitting a clear-to-send CTS frame is provided. The method can be performed by a second device provided in an embodiment of this application. The second device can be an SST STA or a chip implementing functions similar to those of an SST STA. In the method, the second device can receive an RTS frame. The second device transmits a CTS frame at a second transmission rate. The value of the second transmission rate can be a fixed rate. Alternatively, the second device transmits a CTS frame at a third transmission rate. The frame length of the CTS frame transmitted at the third transmission rate is the same as the frame length of the CTS frame transmitted at the fixed rate.
[0032] Based on the above solution, a STA may transmit a CTS frame at a fixed rate. In this case, the frame lengths of CTS frames transmitted by multiple STAs may be the same. Alternatively, a STA may transmit a CTS frame at a non-fixed rate. The frame length of the CTS frame transmitted at the non-fixed rate may be the same as the frame length of the CTS frame transmitted at the fixed rate. Therefore, the frame lengths of CTS frames transmitted by multiple STAs may be the same.
[0033] According to a sixth aspect, there is provided an apparatus having communication capabilities, which may include a module / unit configured to perform the first aspect or any one of its possible implementations, or may further include a module / unit configured to perform the second aspect or any one of its possible implementations, or may further include a module / unit configured to perform the third aspect or any one of its possible implementations, or may further include a module / unit configured to perform the fourth aspect or any one of its possible implementations, or may further include a module / unit, e.g., a processing unit and a communication unit, configured to perform the fifth aspect or any one of its possible implementations.
[0034] For example, when the apparatus is configured to perform the first aspect or any one of the possible implementation forms of the first aspect, the processing unit is configured to generate an MU-RTS frame. The MU-RTS frame may include indication information indicating a first channel. Here, the first channel is a first channel on which the second device transmits the CTS frame. The first channel includes a target channel of the second device. The target channel may be a 20 MHz subchannel within an operating channel of the SST STA. Alternatively, the target channel may be any 20 MHz subchannel other than the primary 20 MHz channel. The communication unit is configured to transmit the MU-RTS frame.
[0035] In a possible implementation, the indication information may include a first bit sequence, which indicates a first channel. Optionally, the indication information may further include a second bit sequence, which has a value of 1 or a reserved state.
[0036] For example, when the device is configured to perform the second aspect or any one of the possible implementation forms of the second aspect, the communication unit is configured to receive an MU-RTS frame. The MU-RTS frame may include indication information. The indication information here may indicate a first channel. The first channel includes a target channel of the second device. The target channel may be a 20 MHz subchannel within an operating channel of the SST STA. Alternatively, the target channel may be any 20 MHz subchannel other than the primary 20 MHz channel. The processing unit is configured to generate a CTS frame. The communication unit is further configured to transmit the CTS frame on the first channel.
[0037] In one design, the indication information may include a first bit sequence indicating a first channel. Optionally, the indication information may further include a second bit sequence having a value of 1 or a reserved state.
[0038] For example, when the device is configured to perform the third aspect or any one of the possible implementation forms of the third aspect, the processing unit generates a first data unit. The first data unit includes at least a second data unit and a third data unit. The second data unit is used to carry a first multi-user request to transmit an MU-RTS frame. The third data unit is used to carry a second MU-RTS frame. The first MU-RTS frame and the second MU-RTS frame use the same scrambling code initialization value. The communication unit is configured to transmit the first data unit.
[0039] In one design, the first MU-RTS frame indicates a first channel on which a second device transmits a clear-to-send CTS frame. The second MU-RTS frame indicates a second channel on which a third device transmits a CTS frame. If the bandwidth of the first channel partially or completely overlaps with the bandwidth of the second channel, the first MU-RTS frame and the second MU-RTS frame use the same scrambling code initialization value.
[0040] In one design, the first data unit includes a plurality of data units, each of which is used to carry an MU-RTS frame, and all of the MU-RTS frames have the same scrambling code initialization value. The second data unit and the third data unit are two of the plurality of data units.
[0041] In one design, the first MU-RTS frame and the second MU-RTS frame each include a first bit sequence, the first bit sequence indicating a bandwidth of the first data unit. Alternatively, the first MU-RTS frame includes a second bit sequence, the second bit sequence indicating a bandwidth of the second data unit. The second MU-RTS frame includes a third bit sequence, the third bit sequence indicating a bandwidth of the third data unit.
[0042] For example, when the apparatus is configured to perform the fourth aspect or any one of the possible implementation forms of the fourth aspect, the processing unit is configured to generate a plurality of request-to-send (RTS) frames, the communication unit is configured to separately transmit the RTS frames on at least two channels, and the communication unit is further configured to receive clear-to-send (CTS) frames having the same frame length on the at least two channels.
[0043] In one design, all RTS frames have the same frame length.
[0044] In one design, the first transmission rate of all RTS frames is the same. Alternatively, the first transmission rate of each RTS frame is used to determine the same second transmission rate, and the second transmission rate is the main rate at which the second device transmits CTS frames.
[0045] For example, when the present apparatus is configured to perform the fifth aspect or any one of the possible implementation forms of the fifth aspect, the communication unit is configured to receive a request-to-send (RTS) frame. The processing unit is configured to generate a clear-to-send (CTS) frame. The communication unit is further configured to transmit the clear-to-send (CTS) frame at a second transmission rate, and the value of the second transmission rate is a fixed rate. Alternatively, the communication unit is further configured to transmit the CTS frame at a third transmission rate. The frame length of the CTS frame transmitted at the third transmission rate is the same as the frame length of the CTS frame transmitted at the fixed rate.
[0046] According to a seventh aspect, there is provided an apparatus having a communication function, the apparatus including a processor and a transceiver, wherein the processor performs the operational steps of the method of the first aspect or any one of its possible implementations, or the operational steps of the method of the second aspect or any one of its possible implementations, or the operational steps of the method of the third aspect or any one of its possible implementations, or the operational steps of the method of the fourth aspect or any one of its possible implementations, or the operational steps of the method of the fifth aspect or any one of its possible implementations. The transceiver performs the receiving and transmitting steps of the method in the first aspect or any one of the possible implementations of the first aspect, or performs the receiving and transmitting steps of the method in the second aspect or any one of the possible implementations of the second aspect, or performs the receiving and transmitting steps of the method in the third aspect or any one of the possible implementations of the third aspect, or performs the receiving and transmitting steps of the method in the fourth aspect or any one of the possible implementations of the fourth aspect, or performs the receiving and transmitting steps of the method in the fifth aspect or any one of the possible implementations of the fifth aspect.
[0047] In one design, the device further includes a memory configured to store computer-executable instructions. When the controller operates, the processor executes the computer-executable instructions in the memory to perform the method of the aforementioned aspect by using hardware resources in the controller. The memory may be located within the device or may be located external to and connected to the device.
[0048] In one design, the memory and processor may be integrated together.
[0049] According to a ninth aspect, there is provided a chip including a communication interface and a logic circuit. The communication interface is configured to input and output information. The logic circuit is configured to perform the method of the previous aspect. For example, the logic circuit can output an MU-RTS frame via the communication interface.
[0050] According to a tenth aspect, the application provides a computer-readable storage medium having instructions stored thereon that, when executed on a computer, enable the computer to perform the method in the aforementioned aspect.
[0051] According to an eleventh aspect, the application provides a computer program product comprising instructions, which when executed on a computer, enable the computer to carry out the method in the above-mentioned aspect.
[0052] Additionally, for the beneficial effects of the second to eleventh aspects, please refer to the beneficial effects of the first to sixth aspects. [Brief explanation of the drawings]
[0053] [Figure 1] FIG. 1 is a schematic diagram of a communication system according to one embodiment of the present application. [Figure 2] FIG. 2 is a schematic diagram of a target channel according to one embodiment of the present application. [Figure 3] FIG. 3 is a schematic diagram of the structure of a trigger frame according to one embodiment of the present application. [Figure 4] FIG. 4 is a schematic diagram of user information of a trigger frame according to one embodiment of the present application. [Figure 5] FIG. 5 is an exemplary flowchart of a method for transmitting MU-RTS and CTS frames according to one embodiment of the present application. [Figure 6] FIG. 6 is a schematic diagram of instruction information and target channels according to one embodiment of the present application. [Figure 7] FIG. 7 is a schematic diagram of transmitting an MU-RTS frame by an AP during puncture according to one embodiment of the present application. [Figure 8] FIG. 8 is a schematic diagram of transmitting multiple MU-RTS frames by an AP according to one embodiment of the present application. [Figure 9] FIG. 9 is an exemplary flowchart of a method for transmitting RTS and CTS frames according to one embodiment of the present application. [Figure 10] FIG. 10 is a schematic diagram of a device having communication capabilities according to one embodiment of the present application. [Figure 11] FIG. 11 is a schematic diagram of a device having communication capabilities according to one embodiment of the present application. DETAILED DESCRIPTION OF THE INVENTION
[0054] Currently, the basic framework commonly used in wireless access standards is one in which an AP accesses the Internet and is associated with multiple stations. Uplink and downlink communications can be performed between the AP and the associated stations. The channel for communications between the AP and the multiple associated stations can support a maximum bandwidth of 320 MHz, and each associated station can communicate with the AP on a designated channel.
[0055] In wireless local area networks, since hidden nodes are common, channels can be reserved for STAs using the RTS / CTS reciprocal method. The principle of the RTS / CTS reciprocal method is that when an AP wants to send a message to a STA, the AP can first send an RTS frame. After receiving the RTS frame, other APs and STAs around the AP can remain quiet. After receiving the RTS frame, the STA can send a CTS frame. After receiving the CTS frame, the AP and STAs around the STA can also remain quiet. After the transmission opportunity (TXOP) duration indicated by the length (Duration) field in the RTS or CTS frame expires, the AP and STAs that remain quiet can restore communication and receive and send messages.
[0056] To improve the efficiency of channel protection, an MU-RTS / CTS interaction mechanism is introduced. The principle of the MU-RTS / CTS interaction mechanism is that an AP can send an MU-RTS frame in a broadcast manner. The MU-RTS frame carries the identifiers of multiple STAs and specifies, for each STA, information about the bandwidth for replying to the CTS frame. After the MU-RTS frame ends, each receiving station can send a CTS frame on the specified bandwidth.
[0057] It should be noted that the channel occupied by the CTS frame can be a primary 20 MHz channel, a primary 40 MHz channel, a primary 80 MHz channel, a primary 160 MHz channel, or a 320 MHz channel.
[0058] However, to fully utilize the channel resources, an SST mechanism may be used to schedule the STA to the secondary channel to transmit and receive data. Because the operating channel of the STA is a secondary channel, the channel cannot be reserved according to the RTS / CTS mechanism or the MU-RTS / CTS mechanism.
[0059] In addition, MU-RTS and RTS frames are transmitted in a non-HT overlap manner. The non-HT overlap frame format can contain four parts: a legacy short raining field (L-STF), a legacy long training field (L-LTF), a legacy signal (L-SIG), and a payload. The payload can contain four parts: a service, a scrambled physical layer service data unit (PSDU), a tail bit, and a pad bit.
[0060] For example, when transmitting an MU-RTS / RTS frame on an 80 MHz bandwidth channel, the AP may repeatedly transmit the MU-RTS / RTS frame on each 20 MHz subchannel. The MU-RTS / RTS frames transmitted on all 20 MHz subchannels are the same. The manner in which an AP transmits an MU-RTS / RTS frame on a 320 MHz bandwidth channel is similar to the manner in which an AP transmits an MU-RTS / RTS frame on an 80 MHz bandwidth channel. The AP may transmit an MU-RTS / RTS frame on each 20 MHz bandwidth subchannel, but the amount of repetition is greater than the amount of repetition when an MU-RTS / RTS frame is transmitted on an 80 MHz bandwidth channel.
[0061] The design of SST in the 802.11ax standard is simple. The AP transmits downlink data to an SST STA or schedules the SST STA to transmit uplink data only when all of the SST STA's operating channels are available. If some 20 MHz subchannels in the SST STA's operating channel are unavailable, the AP cannot communicate with the SST STA. The SST STA cannot predict which 20 MHz subchannel will be used to transmit data and therefore cannot perform frame analysis.
[0062] Based on the above problem, an embodiment of this application provides an MU-RTS frame transmission method. In this method, an AP determines an anchor 20 MHz subchannel for an SST STA on an operating channel. When the anchor 20 MHz subchannel is unavailable, the AP does not perform uplink or downlink communication with the SST STA. When the anchor 20 MHz subchannel is available but some or all of the other 20 MHz subchannels in the operating channel are unavailable, the AP can perform uplink or downlink communication with the SST STA using the RU that includes the anchor 20 MHz subchannel.
[0063] Embodiments of this application may be applied to wireless local area network (WLAN) scenarios, and may be applied to IEEE 802.11 system standards, such as the 802.11a / b / g standard, the 802.11n standard, the 802.11ac standard, the 802.11ax standard, or next-generation standards, such as the 802.11be standard, or successors to the next-generation standards.
[0064] WLAN systems can provide high-speed and low-latency transmission. With the continuous evolution of WLAN application scenarios, WLAN systems will be applied to more scenarios or industries, such as the Internet of Things industry, the Internet of Vehicles industry, the banking industry, enterprise offices, stadium exhibition halls, concert halls, hotel rooms, dormitories, hospital wards, classrooms, supermarkets, squares, streets, production plants, and warehouses. Indeed, devices (such as access points or stations) that support WLAN communication include: Examples of such STAs and APs include sensor nodes in a smart city (e.g., smart water meters, smart electricity meters, or smart air detection nodes), smart devices in a smart home (e.g., smart cameras, projectors, displays, televisions, stereos, refrigerators, or washing machines), nodes in the Internet of Things, entertainment terminals (e.g., AR, VR, or another wearable device), smart devices in a smart office (e.g., printers, projectors, loudspeakers, or stereos), Internet of Vehicle devices in the Internet of Vehicles, infrastructure in everyday life scenarios (e.g., vending machines, self-service navigation stations in supermarkets, self-service cash register devices, or self-service ordering machines), devices in large sports and music venues, etc. The specific forms of the STAs and APs are not limited to the embodiments of this application and are merely examples for the purposes of explanation herein.
[0065] Alternatively, embodiments of this application may be applied to wireless local area network systems, such as Internet of Things (IoT) or Vehicle to Everything (V2X) networks. Indeed, embodiments of this application may also be applied to other possible communication systems, such as long term evolution (LTE) systems, LTE frequency division duplex (FDD) systems, LTE time division duplex (TDD), universal mobile telecommunication system (UMTS), worldwide interoperability for microwave access (WiMAX) communication systems, and future 5G communication systems.
[0066] In one example, the communication system shown in FIG. 1 is used as an example to describe in detail a communication system applicable to an embodiment of this application. FIG. 1 is a schematic diagram of a communication system applicable to a method according to one embodiment of this application. As shown in FIG. 1, the communication system 100 includes an AP1 and multiple STAs associated with the AP1. The multiple STAs associated with the AP1 are STA101 and STA102, respectively. The AP can schedule radio resources for STAs associated with the AP and / or STAs not associated with the AP, and transmit data to the STAs over the scheduled radio resources. For example, AP1 can schedule radio resources for STA1 and STA2, and transmit data including uplink data information and / or downlink data information for STA1 and STA2 over the scheduled radio resources. The AP and STAs in this embodiment of this application can be wireless communication devices supporting parallel transmission over multiple links. It should be understood that the number of APs and STAs in FIG. 1 is merely an example. There may be more or fewer APs and STAs.
[0067] In the embodiments of this application, a STA is a device with wireless communication capabilities, supports communication based on a WLAN protocol, and is capable of communicating with other stations or access points in a WLAN network. In a WLAN system, a station may be referred to as a non-access point station (non-AP STA). For example, a STA is any user communication device that allows a user to communicate with an AP and further with a WLAN. A device with wireless communication capabilities may be an entire device, or may be a chip or processing system integrated into the entire device. A device with a chip or processing system installed can implement the methods and functions of the embodiments of this application under the control of the chip or processing system. For example, a STA may be user equipment capable of connecting to the Internet, such as a tablet computer, desktop computer, laptop computer, notebook computer, ultra-mobile personal computer (UMPC), handheld computer, netbook, personal digital assistant (PDA), or mobile phone. Alternatively, the STA may be an Internet of Things node in the Internet of Things, an in-vehicle communication device in the Internet of Vehicles, an entertainment device, a gaming device or system, a Global Positioning System device, etc. The STA may alternatively be a chip and processing system in the aforementioned terminal.
[0068] An AP in an embodiment of this application is a device having wireless communication capabilities, supports communication based on a WLAN protocol, and has the capability of communicating with other devices (e.g., stations or other access points) in a WLAN network. An AP may also have the capability of communicating with other devices. In a WLAN system, an access point may be referred to as an access point station (AP STA). A device having wireless communication capabilities may be an entire device, or a chip or processing system installed in the entire device. A device with a chip or processing system installed can implement the methods and functions in the embodiments of this application under the control of the chip or processing system. An AP in an embodiment of this application is a device that provides services to STAs and can support 802.11 series protocols. For example, an AP may be a communication entity, such as a communication server, a router, a switch, or a bridge. An AP may include various forms such as a macro base station, a micro base station, or a relay station. Alternatively, an AP may be a chip or processing system in various forms of these devices to implement the methods and functions in the embodiments of this application.
[0069] In order to fully utilize channel resources, AP1 can schedule STA 102 to operate on a secondary channel. The principle is that AP1 can schedule STA 102 to receive downlink data or transmit uplink data on a secondary channel designated in the TWT. STA 102 can be referred to as an SST STA. The operating channel of an SST STA is described below with reference to FIG. 2.
[0070] As shown in FIG. 2 , the primary 20 MHz channel may be channel 1. In this case, a 40 MHz channel that includes the primary 20 MHz channel may be referred to as a primary 40 MHz channel, an 80 MHz channel that includes the primary 20 MHz channel may be referred to as a primary 80 MHz channel, and a 160 MHz channel that includes the primary 20 MHz channel may be referred to as a primary 160 MHz channel. However, the operating channel of an SST STA may not include the primary 20 MHz channel. Therefore, the operating channel of an SST STA does not include the primary 20 MHz channel, the primary 40 MHz channel, the primary 80 MHz channel, or the primary 160 MHz channel. Currently, channels for communication between an AP and a STA can support a maximum bandwidth of 320 MHz. Therefore, the operating channel of an SST STA will be further described using a bandwidth of 320 MHz as an example.
[0071] For example, AP1 schedules STA 102 to operate on a secondary 80 MHz channel. The secondary 80 MHz channel may be any one of channels 5 to 8, channels 9 to 12, and channels 13 to 16. A target channel (anchor channel) may be determined for STA 102. Assume that STA 102 is scheduled to operate on channels 5 to 8, each of which has a bandwidth of 80 MHz. In this case, the target channel for STA 102 may be any one of channels 5 to 8 (channel 5 shown in FIG. 2). The target channel may be referred to as an anchor 20 MHz channel, a 40 MHz channel (e.g., channels 5 to 6) that includes the anchor 20 MHz channel may be referred to as an anchor 40 MHz channel, and an 80 MHz channel (e.g., channels 5 to 8) that includes the anchor 20 MHz channel may be referred to as an anchor 80 MHz channel. The target channel may be referred to as a temporary primary 20 MHz channel or a negotiated 20 MHz channel that is different from the primary 20 MHz channel. The name of the target channel is not limited in this application.
[0072] In another example, AP1 schedules STA 101 to operate on a secondary 160 MHz channel. Because the channel for communication between the AP and the STA can support a maximum bandwidth of 320 MHz, the secondary channel with a bandwidth of 160 MHz may be a 160 MHz channel (e.g., channel 9 to channel 16 shown in FIG. 2) that does not include the primary 20 MHz channel. An anchor channel may be determined for STA 101. The target channel may be referred to as the anchor 20 MHz channel, a 40 MHz channel (e.g., channel 9 to channel 10) that includes the anchor 20 MHz channel may be referred to as the anchor 40 MHz channel, an 80 MHz channel (e.g., channel 9 to channel 12) that includes the anchor 20 MHz channel may be referred to as the anchor 80 MHz channel, and a 160 MHz channel (e.g., channel 9 to channel 16) that includes the anchor 20 MHz channel may be referred to as the anchor 160 MHz channel.
[0073] It should be noted that the anchor 20 MHz channel of STA 101 and STA 102 may be indicated by the AP or may be determined by the AP and the STAs through negotiation. This is not particularly limited in this application. The anchor channel in this embodiment of this application may be another 20 MHz channel other than the primary channel. The primary 20 MHz channel and anchor 20 MHz channel shown in FIG. 2 are merely examples. The primary 20 MHz channel or the anchor 20 MHz channel may alternatively be any one of channel 1 to channel 16.
[0074] In this embodiment of the present application, when an AP schedules a STA to operate on a secondary channel based on the anchor 20 MHz channel, the channel can be reserved for an SST STA according to the MU-RTS / CTS mechanism or the RTS / CTS mechanism. Below, we first describe the structure of the MU-RTS frame with reference to Figures 3 and 4.
[0075] As shown in FIG. 3, the MU-RTS is a trigger frame, and the trigger frame may include one or more user information fields. The user information fields may be shown in FIG. 4. The association identifier (AID) 12 identifies the target STA, and the resource unit allocation (RU Allocation) field may be used to allocate a channel for transmitting the CTS frame to the target STA. The RU Allocation field may include the bit sequence B0 through B7. Therefore, the AP can allocate a channel for transmitting the CTS frame to the SST STA by using the RU Allocation field in the MU-RTS frame.
[0076] 5 is an exemplary flowchart of a MU-RTS frame transmission method according to one embodiment of the present application. The method may include the following steps:
[0077] Step 501: The AP transmits an MU-RTS frame.
[0078] The MU-RTS frame may include indication information, where the indication information may indicate a first channel on which the CTS frame is transmitted, where the first channel may be indicated based on the anchor 20 MHz channel of the SST STA.
[0079] It should be noted that the indication information may include bit sequences B0 through B7. B1 through B7 may be referred to as first bit sequences and indicate the first channel on which the CTS frame is transmitted. B0 may be referred to as second bit sequence and may indicate the operating channel of the SST STA. It should be understood that the value of B0 may be 1 or may be in a reserved state because the SST STA can know the operating channel of the SST STA.
[0080] Below, we will separately explain the cases where different first channels are indicated based on the values of B1 to B7.
[0081] As shown in Figure 2, an 80 MHz bandwidth channel may be referred to as a channel segment. As shown in Figure 2, four channel segments may be included: channel 1 to channel 4 is one segment, channel 5 to channel 8 is one segment, channel 9 to channel 12 is one segment, channel 13 to channel 16 is one segment, channel 9 to channel 12 is one segment, and channel 13 to channel 16 is one segment. In this embodiment of the application, the values of B1 to B7 may be set based on the frequency location of the anchor channel within the channel segment in which the SST STA is located.
[0082] For an SST STA operating on an 80 MHz bandwidth, the operating channel of the SST STA can be any channel segment other than channel 1 through channel 4 in the four channel segments mentioned above. For an STA operating on a 160 MHz bandwidth, the operating channel of the STA can be only two channel segments, namely, channel 9 through channel 12 and channel 13 through channel 16 shown in FIG. 2. A detailed description is provided below.
[0083] Case 1: The first channel is the anchor 20 MHz channel.
[0084] As shown in FIG. 6, if the anchor 20 MHz channel is the subchannel with the lowest frequency in the channel segment, the AP can set the values of B1 through B7 to a first value. If the anchor 20 MHz channel is the subchannel with the second lowest frequency in the channel segment, the AP can set the values of B1 through B7 to a second value. If the anchor 20 MHz channel is the subchannel with the third highest frequency in ascending frequency order in the channel segment, the AP can set the values of B1 through B7 to a third value. If the anchor 20 MHz channel is the subchannel with the fourth highest frequency in ascending frequency order in the channel segment, the AP can set the values of B1 through B7 to a fourth value.
[0085] Alternatively, if the anchor 20 MHz channel is the fourth subchannel in descending frequency order within the channel segment, the AP can set the values of B1 through B7 to a first value. If the anchor 20 MHz channel is the third subchannel in descending frequency order within the channel segment, the AP can set the values of B1 through B7 to a second value. If the anchor 20 MHz channel is the subchannel with the second highest frequency within the channel segment, the AP can set the values of B1 through B7 to a third value. If the anchor 20 MHz channel is the subchannel with the highest frequency within the channel segment, the AP can set the values of B1 through B7 to a fourth value.
[0086] It should be understood that the first value, the second value, the third value, and the fourth value may be predetermined or may be specified in a communication protocol, which is not a limitation in this application.
[0087] For example, the first value may be 61, the second value may be 62, the third value may be 63, and the fourth value may be 64.
[0088] Additionally, it should be noted that if an SST STA is scheduled to operate on a 20 MHz bandwidth channel, the STA's anchor 20 MHz channel may be the SST STA's operating channel. For an SST STA operating on the anchor 20 MHz channel, the values of B1 through B7 received by the SST STA may be only one of the first through fourth values.
[0089] For example, if an AP schedules an SST STA to operate on channel 8 shown in FIG. 2, the SST STA can transmit a CTS frame only on channel 8. The STA's anchor 20 MHz channel is the channel with the highest frequency among channels 5 to 8. Therefore, when the AP transmits an MU-RTS frame to the SST STA, the values of B1 through B7 can only be the fourth value, e.g., 64.
[0090] With this in mind, if the SST STA is an STA operating on a channel with a bandwidth of 20 MHz, the AP can set the values of B1 through B7 to fixed values. For example, the AP can set the values to 0, or the AP can set the values to 1, or the AP can set the values to 61. Optionally, the AP can alternatively set the values of B1 through B7 to a reserved state.
[0091] Case 2: The first channel is the anchor 40 MHz channel.
[0092] As shown in Figure 6, if the anchor 40 MHz channel is the subchannel with the lowest frequency in the channel segment, the AP can set values B1 through B7 to a fifth value. If the anchor 40 MHz channel is the subchannel with the second lowest frequency in the channel segment, the AP can set values B1 through B7 to a sixth value.
[0093] Alternatively, if the anchor 40 MHz channel is the subchannel with the second highest frequency in the channel segment, the AP can set values B1 through B7 to a fifth value. If the anchor 40 MHz channel is the subchannel with the highest frequency in the channel segment, the AP can set values B1 through B7 to a sixth value.
[0094] The fifth value may be 65 and the sixth value may be 66. The fifth and sixth values may be predetermined or may be defined in the communication protocol.
[0095] For example, if an AP schedules an SST STA to operate on channels 5 to 8 shown in FIG. 2 , the anchor 20 MHz channel for the SST STA may be channel 8, which has the highest frequency among channels 5 to 8. If the AP intends to allow the SST STA to transmit a CTS frame on a channel with a bandwidth of 20 MHz, the AP may instruct the SST STA to transmit a CTS frame on channel 8. If the AP intends to allow the SST STA to transmit a CTS frame on a channel with a bandwidth of 40 MHz, the AP may instruct the SST STA to transmit a CTS frame on channels 7 and 8.
[0096] Case 3: The first channel is the anchor 80 MHz channel.
[0097] 6, when the first channel is an anchor 80 MHz channel, the AP can set values B1 to B7 to a seventh value. The seventh value may be 67. The seventh value may be predetermined or specified in the communication protocol.
[0098] For example, if an AP schedules an SST STA to operate on channels 5 to 8 shown in FIG. 2 , the anchor 20 MHz channel for the SST STA may be channel 5, which has the lowest frequency among channels 5 to 8. If the AP intends to allow the SST STA to transmit a CTS frame on a channel with a bandwidth of 20 MHz, the AP may instruct the SST STA to transmit a CTS frame on channel 5. If the AP intends to allow the SST STA to transmit a CTS frame on a channel with a bandwidth of 40 MHz, the AP may instruct the SST STA to transmit a CTS frame on channels 5 and 6. If the AP intends to allow the SST STA to transmit a CTS frame on a channel with a bandwidth of 80 MHz, the AP may instruct the SST STA to transmit a CTS frame on channels 5 to 8.
[0099] In other words, the AP can set the values of B1 through B7 to one of a first value, a fifth value, and a seventh value.
[0100] Case 4: The first channel is the anchor 160 MHz channel.
[0101] As shown in Figure 6, when the first channel is an anchor 160 MHz channel, the AP can set the values B1 to B7 to the eighth value, which may be 68. The eighth value may be predetermined based on an empirical value or may be specified in the communication protocol.
[0102] For example, if an AP schedules an SST STA to operate on channels 9 to 16 shown in FIG. 2 , the anchor 20 MHz channel for the SST STA may be channel 9 in the channels 9 to 16. If the AP intends to enable the SST STA to transmit a CTS frame on a channel with a 20 MHz bandwidth, the AP may instruct the SST STA to transmit a CTS frame on channel 9. If the AP intends to enable the SST STA to transmit a CTS frame on a channel with a 40 MHz bandwidth, the AP may instruct the SST STA to transmit a CTS frame on channels 9 and 10. If the AP intends to enable the SST STA to transmit a CTS frame on a channel with an 80 MHz bandwidth, the AP may instruct the SST STA to transmit a CTS frame on channels 9 to 12. If the AP intends to enable the SST STA to transmit a CTS frame on a channel with a 160 MHz bandwidth, the AP may instruct the SST STA to transmit a CTS frame on channels 9 to 16.
[0103] Since channel 9 is the channel with the lowest frequency in the channel segment, the AP can set the values of B1 through B7 to one of the first, fifth, seventh, and eighth values.
[0104] Based on Case 1 to Case 4, it can be determined that the first channel indicated by the AP needs to include the anchor 20 MHz channel of the SST STA. Cases 1 to 4 describe a method for the AP to indicate the first channel on which the SST STA transmits the CTS frame based on B1 to B7. In this embodiment of the application, the AP can also indicate the resource unit (RU) on which the SST STA transmits the CTS frame based on B1 to B7. The following describes a method for the AP to indicate the RU on which the SST STA transmits the CTS frame.
[0105] If the AP intends to allow SST STAs to transmit CTS frames in a 242-tone RU (representing 26 subcarriers), the AP can set the values of B1 through B7 to one of values 9 through 12. Values 9 through 12 may be the same as values 1 through 4. For example, value 9 may be 61, value 10 may be 62, value 11 may be 63, and value 12 may be 64. Alternatively, values 9 through 12 may be different from values 1 through 4. It should be noted that when an SST STA transmits a CTS frame on a 242-tone RU, the RU includes the anchor 20 MHz channel of the SST STA.
[0106] If the AP intends to allow SST STAs to transmit CTS frames in a 484-tone RU, the AP can set the values of B1 through B7 to one of the 13th and 14th values. The 13th and 14th values may be the same as the 5th and 6th values. For example, the 13th value may be 65, and the 14th value may be 66. Alternatively, the 13th and 14th values may be different from the aforementioned 5th and 6th values. It should be noted that when an SST STA transmits a CTS frame on a 484-tone RU, the RU includes the anchor 20 MHz channel of the SST STA.
[0107] If the AP intends to allow SST STAs to transmit CTS frames in a 996-tone RU, the AP can set values B1 through B7 to the 15th value. The 15th value may be the same as the aforementioned values. For example, the 15th value may be 67. Alternatively, the 15th value may be different from the 7th value. It should be noted that when an SST STA transmits a CTS frame on a 996-tone RU, the RU contains the anchor 20 MHz channel of the SST STA.
[0108] If the AP intends to allow SST STAs to transmit CTS frames in a 2x996 tone RU, the AP can set values B1 through B7 to the 16th value. The 16th value may be the same as the 8th value. For example, the 16th value may be 68. Alternatively, the 16th value may be different from the 8th value. It should be noted that when an SST STA transmits a CTS frame on a 2x996 tone RU, the RU contains the anchor 20 MHz channel of the SST STA.
[0109] For example, see Figure 2. The anchor 20 MHz channel for SST STAs is channel 5, and the operating channels for SST STAs are channels 5 through 8. If the AP intends to allow SST STAs to transmit CTS frames in a 242-tone RU, the AP can set the values of B1 through B7 to the 9th or 1st value. If the AP intends to allow SST STAs to transmit CTS frames in a 484-tone RU, the AP can set the values of B1 through B7 to the 13th or 5th value. If the AP intends to allow SST STAs to transmit CTS frames in a 996-tone RU, the AP can set the values of B1 through B7 to the 15th or 7th value.
[0110] Based on the above solution, the AP can indicate the channel for replying to the CTS frame to the SST STA based on B1 to B7, so that the SST STA can also reserve the channel according to the MU-RTS / CTS mechanism, which can avoid the case where the channel is preempted by a third party station and reduce interference during data reception and transmission.
[0111] In a possible implementation, the AP indicates an anchor 20 MHz channel to the SST STA. When information or data is transmitted to the SST STA, the channel for transmitting the information or data may include the anchor 20 MHz channel to prevent the SST STA from missing the frame transmitted to the SST STA. Based on the above solution, the AP can support transmission of MU-RTS / RTS frames using a preamble puncture method.
[0112] As shown in Figure 7, the second 20 MHz bandwidth subchannel is punctured. If the AP intends to schedule an SST STA to receive and transmit information or data, the AP repeatedly transmits MU-RTS / RTS frames on the unpunctured 20 MHz subchannels and does not transmit information on the punctured subchannel. It should be noted that for an SST STA whose anchor 20 MHz channel is the second 20 MHz bandwidth subchannel, the AP does not schedule the SST STA to receive or transmit data.
[0113] Based on the above solution, when some subchannels in the operating channel of the SST STA are unavailable, the AP can communicate with the SST STA, and the SST STA can also receive information transmitted by the AP on the anchor 20 MHz channel and perform information transmission with the AP.
[0114] In another possible implementation, the AP can transmit multiple MU-RTS frames, at least one of which indicates the channel on which the SST STAs transmit their CTS frames. When the AP transmits multiple MU-RTS frames, the MU-RTS frames can be transmitted on different channels. Compared with a method in which one MU-RTS frame is used to indicate the channel on which to transmit a CTS frame to multiple STAs, in a method in which multiple MU-RTS frames are used to indicate the channel on which to transmit a CTS frame to multiple STAs, the indication information for indicating the channel on which to transmit a CTS frame to multiple STAs can be distributed across different MU-RTS frames. This can reduce the length of the MU-RTS frame. In this way, signaling overhead is reduced, and the probability of hidden node contention during the MU-RTS frame can also be reduced. Since there may be four 80 MHz channel segments within a 320 MHz channel, when a different MU-RTS is transmitted on each 80 MHz channel segment in a 320 MHz channel, only one-quarter of the stations may need to be scheduled in each MU-RTS frame.
[0115] A possible reason why an AP transmits multiple MU-RTS frames is that the stations include high efficiency stations (HE STAs), and the HE STAs do not support 320 MHz channels. Therefore, when the AP transmits one MU-RTS frame on a 320 MHz bandwidth channel, the HE stations cannot be scheduled. In this case, the AP can transmit one MU-RTS frame on the primary 160 MHz channel to schedule the HE STAs and extremely high throughput (EHT STAs), and transmit another MU-RTS frame on the secondary 160 MHz channel to schedule the EHT SST STAs.
[0116] The scrambling code initialization values of some or all of the multiple MU-RTS frames transmitted by the AP may be the same. The scrambling code initialization field is the first 7 bits (B0 to B6) of the service field. The scrambling code initialization value at the transmitting end is the value of the scrambling code initialization field after the scrambling operation, and the scrambling code initialization value at the receiving end is the value of the scrambling code initialization field before the descrambling operation. Since the scrambling code initialization value is obtained after the bits whose initial state is all 0 are scrambled based on a specific scrambler seed, the same scrambling code initialization value is also considered the same scrambler seed. Therefore, in this solution, using the same scrambling code initialization value can be replaced with using the same scrambler seed or the same scrambling code initialization sequence, and the technical effects of the two are the same.
[0117] For example, the AP transmits MU-RTS frame 1, MU-RTS frame 2, MU-RTS frame 3, and MU-RTS frame 4. The scrambling code initialization values for MU-RTS frame 1, MU-RTS frame 2, MU-RTS frame 3, and MU-RTS frame 4 may all be the same.
[0118] In one example, MU-RTS frame 1 indicates that the channels on which the STA will transmit CTS frames are channels 5 through 6. MU-RTS frame 2 indicates that the channels on which the STA will transmit CTS frames are channels 5 through 8. MU-RTS frame 3 indicates that the channels on which the STA will transmit CTS frames are channels 9 through 10. MU-RTS frame 4 indicates that the channels on which the STA will transmit CTS frames are channels 11 and 12. The bandwidths of some of the channels indicated by MU-RTS frame 1 and MU-RTS frame 2 overlap. Therefore, MU-RTS frame 1 and MU-RTS frame 2 can use the same scrambling code initialization value. The scrambling code initialization value used by MU-RTS frame 3 may be the same as or different from the value used by MU-RTS frame 1 and MU-RTS frame 2. The scrambling code initialization value used by MU-RTS frame 4 may be the same as or different from the value used by MU-RTS frame 1 and the value used by MU-RTS frame 2. And the scrambling code initialization value used by MU-RTS frame 4 may be the same as or different from the value used by MU-RTS frame 3.
[0119] For example, see Figure 8. The AP can transmit MU-RTS1 to STA1 on channels 1 to 4 and MU-RTS2 to STA2 on channels 5 to 8. MU-RTS1 indicates the channel on which STA1 transmits its CTS frame. MU-RTS2 indicates the channel on which SST STA2 transmits its CTS frame.
[0120] In one example, channel 1 may be the primary 20 MHz channel. Assume that MU-RTS1 indicates that STA1 transmits a CTS frame on channel 5 to channel 8, and MU-RTS2 indicates that STA2 transmits a CTS frame on channel 1 to channel 8. STA1 may be an SST STA. The bandwidths of the channels on which STA1 and STA2 transmit their CTS frames partially overlap. Therefore, the CTS frame transmitted by STA1 and the CTS frame transmitted by STA2 should be exactly the same to avoid contention. Because the scrambling code initialization value of a CTS frame is the same as the scrambling code initialization value of the corresponding MU-RTS frame, MU-RTS1 and MU-RTS2 must use the same scrambling code initialization value.
[0121] In another example, channel 9 may be the primary channel (not shown). Assume that MU-RTS1 indicates that STA1 transmits a CTS frame on channel 5 to channel 8, and MU-RTS2 indicates that STA2 transmits a CTS frame on channel 1 to channel 8. STA1 and STA2 are both SST STAs. The bandwidths of the channels on which STA1 and STA2 transmit their CTS frames partially overlap. Therefore, the CTS frame transmitted by STA1 and the CTS frame transmitted by STA2 should be exactly the same to avoid contention. Because the scrambling code initialization value of a CTS frame is the same as the scrambling code initialization value of the corresponding MU-RTS frame, MU-RTS1 and MU-RTS2 must use the same scrambling code initialization value.
[0122] Based on the above solution, if the channels indicated for transmitting CTS frames overlap in multiple MU-RTS frames, the MU-RTS frames indicating these channels for transmitting CTS frames can use the same scrambling code initialization value. This can reduce the problem of contention between CTS frames. The AP can accurately receive multiple CTS frames.
[0123] Optionally, when an AP transmits multiple MU-RTS frames, all MU-RTS frames can use the same scrambling code initialization value. For example, the AP transmits MU-RTS1 on channel 1 to channel 4, MU-RTS2 on channel 5 to channel 8, and MU-RTS3 on channel 9 to channel 16. The scrambling code initialization values of MU-RTS1, MU-RTS2, and MU-RTS3 may all be the same.
[0124] Based on the above solution, the AP may allow multiple MU-RTS frames to all use the same scrambling code initialization value, which can reduce the contention problem between CTS frames and also reduce the computing resources of the AP.
[0125] In this embodiment of the application, the MU-RTS frame may include a scrambler sequence field. The AP can indicate the bandwidth of the PPDU carrying the MU-RTS frame by using some bits in the scrambler sequence field, such as the B5 and B6 bits. For example, PPDU1 carries MU-RTS1, and PPDU2 carries MU-RTS2. The AP can set the B5 and B6 bits in the scrambler sequence field of MU-RTS1 to the bandwidth of PPDU1, or set the B5 and B6 bits in the scrambler sequence field of MU-RTS2 to the bandwidth of PPDU2. Optionally, the AP can aggregate PPDU1 carrying MU-RTS1 and PPDU2 carrying MU-RTS2 into one PPDU, such as PPDU3. It should be noted that the AP can carry the MU-RTS in a PPDU, and the AP can transmit multiple PPDUs to transmit multiple MU-RTSs. Alternatively, the AP may transmit one PPDU, which may include multiple PPDUs carrying MU-RTS, or a PPDU may be formed by aggregating multiple PPDUs carrying MU-RTS.
[0126] Additionally, it should be noted that if the bandwidth of PPDU1 carrying MU-RTS1 is different from the bandwidth of PPDU2 carrying MU-RTS2, the scrambler sequence field of MU-RTS1 will be different from the scrambler sequence field of MU-RTS2, and therefore the scrambling code initialization values of MU-RTS1 and MU-RTS2 will be different.
[0127] Therefore, if MU-RTS1 and MU-RTS2 need to use the same scrambling code initialization value, some bits in the scrambler sequence field of at least one of the MU-RTS frames of MU-RTS1 and MU-RTS2 do not indicate the bandwidth of the PPDU carrying the MU-RTS frame. For example, if the B5 and B6 bits in the scrambler sequence field of MU-RTS1 may indicate the bandwidth of PPDU1, the B5 and B6 bits in the scrambler sequence field of MU-RTS2 may be the same as the B5 and B6 bits in MU-RTS1 but do not indicate the bandwidth of PPDU2. Alternatively, neither the B5 and B6 bits in the scrambler sequence field of MU-RTS1 nor the B5 and B6 bits in the scrambler sequence field of MU-RTS2 indicate the respective bandwidths of the PPDUs carrying MU-RTS1 and MU-RTS2. The AP may generate the same random number for the B5 and B6 bits in the scrambler sequence fields of MU-RTS1 and MU-RTS2.
[0128] Based on the above solution, the B5 and B6 bits in the scrambler sequence field can be used to indicate the total bandwidth of the data unit transmitted by the AP. Alternatively, when the channels indicated for replying to the CTS frame overlap, the B5 and B6 bits in the scrambler sequence field of at least one of the MU-RTS frames indicating the channel for replying to the CTS frame may not indicate the bandwidth of the PPDU carrying the MU-RTS frame, and the MU-RTS frames indicating that the channels for replying to the CTS frame overlap can use the same scrambling code initialization value.
[0129] In a possible implementation, MU-RTS1 may be carried in physical protocol data unit 1 (PPDU), and MU-RTS2 may be carried in PPDU2. The end times at which the AP transmits PPDU1 and PPDU2 may be aligned. For example, when the AP transmits PPDU1 by using time domain symbols, the last time domain symbol may be the symbol with index 20. Therefore, when the AP transmits PPDU2 by using time domain symbols, the last time domain symbol may be the symbol with index 20.
[0130] Optionally, the start times of PPDU1 and PPDU2 may also be aligned, and the frame lengths of PPDU1 and PPDU2 may be the same. For example, an AP may transmit PPDU1 by using 20 time domain symbols, and the AP may also transmit PPDU2 by using the same 20 time domain symbols.
[0131] In a possible implementation, the uplink bandwidth (UL BW) field in the common info field of the MU-RTS frame can indicate the bandwidth of the PPDU carrying the MU-RTS frame or the total bandwidth of the PPDUs transmitted by the AP. For example, an AP transmits PPDU0, which includes PPDU1 and PPDU2. PPDU1 carries MU-RTS1, and PPDU2 carries MU-RTS2. The AP can set the UL BW field of MU-RTS1 to the bandwidth of PPDU1 and the UL BW field to the bandwidth of PPDU0. The AP can also set the UL BW of MU-RTS2 to the bandwidth of PPDU2, or set the UL BW to the bandwidth of PPDU0.
[0132] Because multiple MU-RTS frames transmitted by the AP are used for the same transmission opportunity (TXOP), the time reserved for SST STAs should be the same. The reserved time may be the time reserved for SST STAs to receive and transmit data. Therefore, the duration fields of multiple MU-RTS frames may be set to the same value.
[0133] Step 502: The SST STA transmits a CTS frame on the first channel.
[0134] The SST STA can determine the first channel based on the values of the bit sequence B1 to B7 in the indication information. The method for determining the first channel based on the values of B1 to B7 is described below.
[0135] If the values of B1 to B7 are fixed or in a reserved state, the first channel can be determined to be the anchor 20 MHz channel of the SST STA.
[0136] 2, if the anchor 20 MHz channel of an SST STA is channel 13 and the values of B1 to B7 in the MU-RTS frame received by the SST STA are fixed values or in the reserved state, the SST STA can transmit a CTS frame on channel 13. The SST STA can transmit a CTS frame on channel 13 when channel 13 is idle.
[0137] If the values of B1 through B7 are one of the first through fourth values, the first channel can be determined to be the anchor 20 MHz channel of the SST STA. If the values of B1 through B7 are the fifth or sixth values, the first channel can be determined to be the anchor 40 MHz channel of the SST STA. If the values of B1 through B7 are the seventh value, the first channel can be determined to be the anchor 80 MHz channel of the SST STA. If the values of B1 through B7 are the eighth value, the first channel can be determined to be the anchor 160 MHz channel of the SST STA.
[0138] For the first to eighth values here, please refer to the related explanations in Case 1 to Case 4. The details will not be explained again here.
[0139] As shown in FIG. 2, it is assumed that the operating channel of an SST STA is a 160 MHz channel and that the anchor 20 MHz channel of the SST STA is channel 13. If the values of B1 through B7 in the MU-RTS frame received by the SST STA are 61, the SST STA can transmit a CTS frame on channel 13. If the values of B1 through B7 in the MU-RTS frame received by the SST STA are 65, the SST STA can transmit a CTS frame on channels 13 and 14. If the values of B1 through B7 in the MU-RTS frame received by the SST STA are 67, the SST STA can transmit a CTS frame on channel 13 to channel 16. If the values of B1 through B7 in the MU-RTS frame received by the SST STA are 68, the SST STA can transmit a CTS frame on channel 9 to channel 16.
[0140] If the value of B1 through B7 is one of the 9th through 12th values, the SST STA can transmit a CTS frame on a 242-tone RU. The 242-tone RU may be an anchor 20 MHz channel. If the value of B1 through B7 is one of the 13th and 14th values, the SST STA can determine to transmit a CTS frame on a 484-tone RU. The 484-tone RU may be an anchor 40 MHz channel. If the value of B1 through B7 is the 15th value, the SST STA can determine to transmit a CTS frame on a 996-tone RU. The 996-tone RU may be an anchor 80 MHz channel. If the value of B1 through B7 is the 16th value, the SST STA can determine to transmit a CTS frame on a 2×996-tone RU. The 2x996 tone RU may be the anchor 160 MHz channel.
[0141] For the 9th to 16th values here, please refer to the related descriptions in the above method for an SST STA to indicate to an AP the RU to which the SST STA sends a CTS frame, and the details will not be described again here.
[0142] For example, assume that an SST STA's operating channel is a 160 MHz channel and its anchor 20 MHz channel is channel 13. If the values of B1 through B7 in the MU-RTS frame received by the SST STA are 61, the SST STA can transmit a CTS frame on the anchor 20 MHz channel and channel 13. If the values of B1 through B7 in the MU-RTS frame received by the SST STA are 65, the SST STA can transmit a CTS frame on the anchor 40 MHz channel, channel 13, and channel 14. If the values of B1 through B7 in the MU-RTS frame received by the SST STA are 66, the SST STA can transmit a CTS frame on the anchor 80 MHz channel and channels 13 through 16. If the values of B1 through B7 in the MU-RTS frame received by the SST STA are 68, the SST STA can transmit a CTS frame on the anchor 160 MHz channel and channels 9 through 16.
[0143] In a possible implementation, the scrambling code initialization value of the CTS frame is the same as the scrambling code initialization value of the MU-RTS frame. For example, an SST STA receives MU-RTS1, and MU-RTS1 instructs the SST STA to transmit a CTS frame on the anchor 20 MHz channel. The SST STA can transmit the CTS frame when the anchor 20 MHz channel is idle. The scrambling code initialization value of the CTS frame is the same as the scrambling code initialization value of MU-RTS1.
[0144] Based on the above solution, the AP can use the MU-RTS frame to indicate to the SST STA the channel for replying to the CTS frame, so that the SST STA can also reserve a channel according to the MU-RTS / CTS mechanism, facilitating the reception and transmission of follow-up data by the SST STA and the AP. In addition, the AP can send multiple MU-RTS frames to indicate to multiple STAs the channel for replying to the CTS frame, and the same scrambling code initialization value can be used in some or all of the multiple MU-RTS frames to avoid contention between the CTS frames.
[0145] An embodiment of this application provides an RTS frame and CTS frame transmission method. Figure 9 is an exemplary flowchart of an RTS frame and CTS frame transmission method according to an embodiment of this application. This method may include the following steps:
[0146] Step 901: The AP transmits an RTS frame separately on at least two channels.
[0147] When the AP transmits at least two RTS frames, the frame lengths of the at least two RTS frames are the same. For example, the AP transmits RTS1 and RTS2 on at least two channels. The AP uses 13 time domain symbols to transmit RTS1, and the AP also uses 13 time domain symbols to transmit RTS2. It should be understood that at least one of the at least two RTS frames indicates a channel on which the SST STA transmits a CTS frame.
[0148] In a possible implementation, the AP can transmit all RTS frames at a first rate, for example, the first rate may be 6 mb / s, which is not particularly limited in this application.
[0149] In another possible implementation, when an AP transmits multiple RTS frames, each RTS frame may be transmitted at a different rate, or some RTS frames may be transmitted at different rates. The same main rate may be determined for the rate of each RTS frame. It should be noted that when a STA transmits a CTS frame, the CTS frame may be transmitted at the main rate. The main rate may be determined by the STA in a first rate set. The main rate is equal to or less than the second rate of the RTS frame. If the first rate set does not include a main rate equal to or less than the second rate of the RTS frame, the STA may determine a mandatory rate in a second rate set to transmit the CTS frame. The mandatory rate is equal to or less than the second rate of the RTS frame. Therefore, the AP may transmit RTS frames at different rates separately. However, to allow multiple received CTS frames to have the same frame length, the same main rate or the same mandatory rate may be determined from the aforementioned different rates. The STA may transmit the CTS frame at the determined main rate or the mandatory rate as the main rate.
[0150] Based on the above solution, the AP can transmit multiple RTS frames at the same rate, or the AP can transmit multiple RTS frames at different rates, and the main rate of one CTS frame can be determined from these different rates. In this way, the AP can control the rate at which multiple RTS frames are transmitted to control the main rate of the CTS frame, and can simultaneously transmit data to multiple STAs within a SIFS time after the CTS ends. This avoids the case where the channel is occupied by a third party station due to a channel idle time greater than a SIFS in some subchannels.
[0151] When an AP transmits multiple RTS frames, each STA transmits a CTS frame on a different channel segment, and there is no frequency overlap. Therefore, dynamic bandwidth negotiation can be implemented. Before dynamic bandwidth negotiation is implemented, an anchor 20 MHz subchannel may be determined for the SST STA, and when transmitting a CTS frame, the SST STA needs to select a bandwidth including the anchor 20 MHz subchannel. Alternatively, the AP can transmit an RTS frame by using the method for transmitting an MU-RTS frame in the embodiment shown in FIG. 5 to indicate the channel or RU on which the SST STA will transmit the CTS frame.
[0152] Step 902: The STA transmits a CTS frame.
[0153] In a possible implementation, when transmitting a CTS frame, the STA can determine a main rate based on the rate of the RTS frame. The main rate can be determined by the STA in a first rate set. The main rate is equal to or less than the rate of the RTS frame. If the first rate set does not include a main rate that is equal to or less than the rate of the RTS frame, the STA can determine a mandatory rate in a second rate set for transmitting the CTS frame. The mandatory rate is equal to or less than the rate of the RTS frame.
[0154] Thus, the STA can determine a rate within the first rate set or the second rate set, and then the STA can transmit a CTS frame at the rate determined as the main rate.
[0155] In another possible implementation, when transmitting a CTS frame, the STA may transmit the CTS frame at a fixed rate. For example, the CTS frame may be transmitted at a rate of 6 mb / s. It should be understood that the fixed rate may be predetermined based on an empirical value or may be specified in a communication protocol. This is not particularly limited in this application.
[0156] In yet another possible implementation, when transmitting a CTS frame, the STA may transmit the CTS frame at an alternative rate. It should be noted that the frame length of the CTS frame transmitted at the alternative rate is the same as the frame length of the CTS frame transmitted at a fixed rate. For example, if the STA occupies 12 time domain symbols when transmitting a CTS frame at a fixed rate, the CTS frame also occupies 12 time domain symbols when the STA transmits a CTS frame at an alternative rate.
[0157] Based on the above solution, a STA can transmit a CTS frame at a fixed rate, or different STAs can transmit CTS frames at different rates, but the frame length of the CTS frames transmitted at different rates is the same as the frame length of the CTS frame transmitted at a fixed rate. In this way, the frame length of multiple CTS frames received by the AP can be the same. After the CTS ends, the AP can simultaneously transmit data to multiple STAs within a SIFS time. This avoids the case where the channel is occupied by a third party due to a channel idle time greater than a SIFS in some subchannels.
[0158] FIG. 10 is a schematic block diagram of a device 1000 with a communication function according to an embodiment of this application. The device 1000 may be a MU-RTS frame transmitting device referred to in the embodiments of this application, a protocol data unit (PPDU) transmitting device referred to in the embodiments of this application, or a request-to-send RTS frame transmitting device referred to in the embodiments of this application. The device 1000 may correspondingly perform the functions or steps performed by the first device in the above-mentioned method embodiments. The device may include a processing unit 1010 and a communication unit 1020. Optionally, the device may further include a storage unit. The storage unit may be configured to store instructions (code or program) and / or data. The processing unit 1010 and the communication unit 1020 may be coupled to the storage unit. For example, the processing unit 1010 may read instructions (code or program) and / or data in the storage unit and perform the corresponding method. The aforementioned units may be independently located or, alternatively, may be partially or fully integrated.
[0159] In some possible implementations, the apparatus 1000 can correspondingly implement the behavior and functions of the first device in the method embodiments. For example, the apparatus 1000 may be an AP or a component (e.g., a chip or circuit) used in an AP. The communication unit 1020 may be configured to perform all receiving or transmitting operations performed by the first device in the embodiment shown in FIG. 5 or FIG. 9, such as steps 501 and 502 in the embodiment shown in FIG. 5, and / or may be configured to support other processes of the technology described herein, such as steps 901 and 902 in the embodiment shown in FIG. 9, and / or may be configured to support other processes of the technology described herein. The processing unit 1010 is configured to perform all operations other than receiving and transmitting operations performed by the first device in the embodiment shown in FIG. 5 or FIG. 9, such as generating an MU-RTS frame, generating a first data unit, or generating an RTS frame, and / or to support other processes of the technology described herein.
[0160] It should be understood that the processing unit 1010 in the embodiments of this application may be implemented by a processor or processor-related circuit components, and the communication unit 1020 may be implemented by a transceiver, transceiver-related circuit components, or a communication interface.
[0161] In one example, the processing unit 1010 is configured to generate an MU-RTS frame. The MU-RTS frame may include indication information indicating a first channel, where the first channel is a first channel on which the second device transmits the CTS frame. The first channel includes a target channel of the second device. The target channel may be a 20 MHz subchannel within the operating channel of the SST STA. Alternatively, the target channel may be any 20 MHz subchannel other than the primary 20 MHz channel. The communication unit 1020 is configured to transmit the MU-RTS frame.
[0162] For the indication information and the first channel, please refer to the relevant descriptions in the method embodiments shown in Figure 5 or Figure 9. The details will not be described again here.
[0163] In one example, the processing unit 1010 generates a first data unit. The first data unit includes at least a second data unit and a third data unit. The second data unit is used to carry a first multi-user request to transmit an MU-RTS frame. The third data unit is used to carry a second MU-RTS frame. The first MU-RTS frame and the second MU-RTS frame use the same scrambling code initialization value. The communication unit 1020 is configured to transmit the first data unit.
[0164] For the scrambling code initialization value, please refer to the relevant description in the method embodiment shown in Figure 5 or Figure 9. The details will not be described again here.
[0165] In one example, the processing unit 1010 is configured to generate a plurality of request-to-send (RTS) frames. The communication unit 1020 is configured to separately transmit the RTS frames on at least two channels. The communication unit 1020 is further configured to receive a clear-to-send (CTS) frame having the same frame length on the at least two channels.
[0166] For the RTS frame and the CTS frame, please refer to the relevant descriptions in the method embodiments shown in Figure 5 or Figure 9. The details will not be described again here.
[0167] In some possible implementations, the device may be a clear-to-send CTS frame transmitting device referred to in the embodiments of this application. The device 1000 may correspondingly implement the behavior and functions of the second device in the above-mentioned method embodiments. For example, the device 1000 may be an STA or a component (e.g., a chip or circuit) used in an STA. The communication unit 1020 may be configured to perform all receiving or transmitting operations performed by the second device in the embodiment shown in FIG. 5 or FIG. 9, such as steps 501 and 502 in the embodiment shown in FIG. 5, and / or may be configured to support other processes of the technology described in this specification, such as steps 901 and 902 in the embodiment shown in FIG. 9, and / or may be configured to support other processes of the technology described in this specification. The processing unit 1010 is configured to perform all operations, such as generating a CTS frame, performed by the second device in the embodiment shown in FIG. 5 or FIG. 9 other than receiving and transmitting operations, and / or to support other processes of the technology described in this specification.
[0168] In one example, the communication unit 1020 is configured to receive an MU-RTS frame. The MU-RTS frame may include indication information, which may indicate a first channel. The first channel may include a target channel for the second device. The target channel may be a 20 MHz subchannel within the operating channel of the SST STA. Alternatively, the target channel may be any 20 MHz subchannel other than the primary 20 MHz channel. The processing unit 1010 is configured to generate a CTS frame. The communication unit is further configured to transmit the CTS frame on the first channel.
[0169] For the indication information and the first channel, please refer to the relevant descriptions in the method embodiments shown in Figure 5 or Figure 9. The details will not be described again here.
[0170] In one example, the processing unit 1010 is configured to generate a plurality of request-to-send (RTS) frames. The communication unit 1020 is configured to separately transmit the RTS frames on at least two channels. The communication unit 1020 is further configured to receive a clear-to-send (CTS) frame having the same frame length on the at least two channels.
[0171] For the RTS frame and the CTS frame, please refer to the relevant descriptions in the method embodiments shown in Figure 5 or Figure 9. The details will not be described again here.
[0172] It should be understood that the processing unit 1010 in the embodiments of this application may be implemented by a processor or a processor-related circuit component, and the communication unit 1020 may be implemented by a transceiver, a transceiver-related circuit component, or a communication interface.
[0173] FIG. 11 shows a device 1100 having a communication function according to an embodiment of the present invention. The device 1100 may be a first device and may implement the functions of the first device in the methods provided in the embodiments of this application. Alternatively, the device 1100 may be a second device and may implement the functions of the second device in the methods provided in the embodiments of this application. Alternatively, the device 1100 may be a device capable of supporting the first device in implementing the corresponding functions of the methods provided in the embodiments of this application, or a device capable of supporting the second device in implementing the corresponding functions of the methods provided in the embodiments of this application. The device 1100 may be a chip or a chip system. In this embodiment of this application, the chip system may include a chip, or may include a chip and other discrete components.
[0174] It should be understood that the device 1100 may be an MU-RTS frame transmitting device referred to in an embodiment of this application, or may be a protocol data unit (PPDU) transmitting device referred to in an embodiment of this application, or may be a request-to-send RTS frame transmitting device referred to in an embodiment of this application, or may be a clear-to-send CTS frame transmitting device referred to in an embodiment of this application.
[0175] In a hardware implementation, the communication unit 1020 may be a transceiver 1110 .
[0176] The apparatus 1100 includes at least one processor 1120 configured to implement or support the apparatus 1100 in implementing the functionality of the first device or the second device in the methods provided in the embodiments of this application, for example, to indicate a channel for replying to the CTS frame based on the values of B1 through B7. The processor may include an MU-RTS frame identification component and / or an RTS frame identification component. The MU-RTS frame identification component and / or the RTS frame identification component may be configured to perform the steps performed by the first device and the second device provided in the embodiments of this application.
[0177] The device 1100 may further include at least one memory 1130 configured to store program instructions and / or data. The memory 1130 is coupled to the processor 1120. A coupling in this embodiment of the present application may be an indirect coupling or communication connection between devices, units, or modules in an electrical, mechanical, or other form, and is used for information exchange between the devices, units, or modules. The processor 1120 may operate together with the memory 1130. The processor 1120 may execute the program instructions and / or data stored in the memory 1130, such that the device 1100 performs a corresponding method. At least one of the at least one memory may be located within the processor.
[0178] The apparatus 1100 may further include a transceiver 1110 configured to communicate with another device via a transmission medium, such that the apparatus within the apparatus 1100 can communicate with the other device. For example, if the apparatus is an AP, the other device is a STA. Alternatively, if the apparatus is a STA, the other device is an AP. The processor 1120 can receive data and transmit data by using the transceiver 1110. The transceiver 1110 may specifically be a transceiver. The apparatus 1100 may further include a radio frequency unit. The radio frequency unit may be separate from the apparatus 1100 or may be integrated into the apparatus 1100. Indeed, the transceiver 1110 may further include an antenna. For example, a remote antenna separate from the apparatus 1100 or an antenna integrated into the apparatus 1100.
[0179] The particular connection medium between the transceiver 1110, the processor 1120, and the memory 1130 is not limited in this embodiment of the application. In this embodiment of the application, the memory 1130, the processor 1120, and the transceiver 1110 are connected via a bus 1140 in FIG. 11. The bus is represented by using a thick line in FIG. 11. The connection method of the other components is merely an example for purposes of illustration and is not limited thereto. The bus can be categorized into an address bus, a data bus, a control bus, etc. For ease of representation, only one thick line is used to represent the bus in FIG. 11, but this does not imply that there is only one bus or only one type of bus.
[0180] In this embodiment of the application, the processor 1120 may be a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component, and may implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of the application. The general-purpose processor may be a microprocessor, or any conventional processor, etc. The steps of the methods disclosed with reference to the embodiments of the application may be performed directly by a hardware processor, or may be performed by using a combination of hardware and software modules in the processor.
[0181] In this embodiment of the application, the memory 1130 may be a non-volatile memory, such as a hard disk drive (HDD) or a solid state drive (SSD), or a volatile memory, such as a random-access memory (RAM). The memory is any other medium that can carry or store expected program code in the form of instructions or data structures and that can be accessed by a computer, but is not limited thereto. The memory in this embodiment of the application may alternatively be a circuit or any other device that can implement a storage function and is configured to store program instructions and / or data.
[0182] It should be noted that the apparatus in the above embodiments may be a terminal, a circuit, a chip used in a terminal, or another combined device or component having the functionality of a terminal. When the apparatus is a terminal, the communication unit may be a transceiver and may include an antenna, a radio frequency circuit, etc. The processing unit may be a processor, for example, a central processing unit (CPU). When the apparatus is a component having the functionality of a terminal, the communication unit may be a radio frequency unit, and the processing unit may be a processor. When the apparatus is a chip or a chip system, the communication unit may be an input / output interface of the chip or chip system, and the processing unit may be a processor of the chip or chip system.
[0183] As a possible product form, the AP or STA described in this embodiment of the present application may further be implemented using the following components: one or more field programmable gate arrays (FPGAs), programmable logic devices (PLDs), controllers, state machines, gate logic, discrete hardware components, any other suitable circuitry, or any combination of circuitry capable of performing the various functions described in this application.
[0184] It should be understood that the AP in various product forms may have any function of the AP in the above-mentioned method embodiment. Details will not be described again here. The STA in various forms may have any function of the STA in the above-mentioned method embodiment. Details will not be described again here.
[0185] An embodiment of the present application further provides a communication system. Specifically, the communication system may include a STA and an AP, or may further include more APs and STAs. For example, the communication system may include a STA and an AP configured to implement the relevant functions in FIG. 5 or FIG. 9.
[0186] The AP is separately configured to implement the relevant functions of the AP portion in Figure 5 or Figure 9. The STA is configured to implement the relevant functions of the STA in Figure 5 or Figure 9. For example, the STA can perform steps 501 and 502 in the embodiment shown in Figure 5, and the AP can perform steps 501 and 502 in the embodiment shown in Figure 5. As another example, the STA can perform steps 901 and 902 in the embodiment shown in Figure 9, and the AP can perform steps 901 and 902 in the embodiment shown in Figure 9.
[0187] An embodiment of the present application further provides a computer-readable storage medium containing instructions, which, when executed on a computer, enable the computer to perform the method performed by the AP or STA in FIG.
[0188] An embodiment of the present application further provides a computer program product including computer program code, which, when executed on a computer, enables the computer to perform the method performed by the AP or STA in FIG. 5 or FIG. 9.
[0189] An embodiment of the present application provides a chip system, which includes a processor and may further include memory, and is configured to implement the functions of an AP or STA in the aforementioned method. The chip system may include a chip, or may include a chip and other discrete components.
[0190] An embodiment of the present application further provides an apparatus including a processor and an interface, the processor configured to perform the method in each aspect of any one of the aforementioned method embodiments.
[0191] It should be understood that the device may be a chip. The processor may be implemented in hardware or in software. When the processor is implemented in hardware, it may be a logic circuit, an integrated circuit, etc. When the processor is implemented in software, it may be a general-purpose processor and is implemented by reading software code stored in a memory. The memory may be integrated with the processor or may be located external to the processor and exist independently.
[0192] It should be understood that the terms "system" and "network" may be used interchangeably in the embodiments of this application. "At least one" means one or more, and "a plurality of" means two or more. The term "and / or" describes an association relationship between related objects and may indicate a triple relationship. For example, A and / or B may indicate: only A is present; both A and B are present; and only B is present, where A and B may be singular or plural. The character " / " generally indicates an "or" relationship between associated objects. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of singular items or plural items. For example, at least one item (piece) of a, b, or c can represent a, b, c, a and b, a and c, b and c, or a, b and c, where a, b, and c can be singular or plural.
[0193] Additionally, unless otherwise specified, ordinal numbers such as "first" and "second" in the embodiments of this application are used to distinguish between multiple objects, but are not intended to limit the order, chronology, priority, or importance of the multiple objects. For example, first information and second information are used merely to distinguish between different pieces of information, and do not indicate different priorities, importance, etc., between the two types of information.
[0194] It should be understood that the sequence numbers of the above processes do not mean the execution sequence in various embodiments of this application, and the execution sequence of the processes should be determined according to the functions and internal logic of the processes, and should not be construed as any limitation on the implementation process of the embodiments of this application.
[0195] Additionally, the term "for example" in the embodiments of this application is used to denote an example or illustration. Any embodiment or implementation solution described as an "example" in the embodiments of this application should not be described as preferred over another embodiment or implementation solution. That is, the word "example" is used to present a concept in a particular way.
[0196] All or part of the methods in the embodiments of this application may be implemented by using software, hardware, firmware, or any combination thereof. When software is used to implement the embodiments, all or part of the embodiments may be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded into a computer and executed, the procedures or functions according to the embodiments of the present invention are generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, a network device, user equipment, or another programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from a computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, optical fiber, or digital subscriber line (DSL)) or wireless (e.g., infrared, radio, or microwave) transmission. The computer-readable storage medium may be any available medium that can be accessed by a computer, or a data storage device, such as a server or data center, that consolidates one or more available media. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, or a magnetic tape), an optical medium (e.g., a digital video disc (DVD)), a semiconductor medium (e.g., an SSD), etc.
[0197] It is obvious that a person skilled in the art can make various modifications and variations to this application without departing from the scope of this application. This application is intended to cover these modifications and variations of this application, provided that they fall within the scope of protection defined by the following claims and their equivalent technologies.
Claims
1. A method for transmitting a protocol data unit (PPDU), comprising: transmitting, by the first device, a first data unit; the first data unit includes at least a second data unit and a third data unit; the second data unit is used to carry a first multi-user request to send (MU-RTS) frame; and the third data unit is used to carry a second MU-RTS frame; Steps, including: the first MU-RTS frame and the second MU-RTS frame use the same scrambling code initialization value; The end times of transmitting the first MU-RTS frame and the second MU-RTS frame are aligned; and The transport of the first MU-RTS frame and the transport of the second MU-RTS frame are aggregated into one PPDU; The MU-RTS frame indicates the bandwidth of the PPDU in the uplink bandwidth field and is transmitted in a non-HT overlapping manner; The format of the non-HT duplicate frame includes four parts: a legacy short training field, a legacy long training field, a legacy signal, and a payload. method.
2. The first MU-RTS frame indicates a first channel on which a second device transmits a clear-to-send CTS frame; The second MU-RTS frame indicates a second channel on which a third device transmits a CTS frame; When the bandwidth of the first channel partially or completely overlaps with the bandwidth of the second channel, the first MU-RTS frame and the second MU-RTS frame use the same scrambling code initialization value. The method of claim 1.
3. the first data unit includes a plurality of data units; each of the plurality of data units is used to carry an MU-RTS frame; The scrambling code initialization value for all MU-RTS frames is the same, and the second data unit and the third data unit are two of the plurality of data units; The method of claim 1.
4. the first MU-RTS frame and the second MU-RTS frame each include a first bit sequence; and the first bit sequence indicates a bandwidth of the first data unit; or the first MU-RTS frame includes a second bit sequence; the second bit sequence indicates a bandwidth of the second data unit; the second MU-RTS frame includes a third bit sequence; and the third bit sequence indicating a bandwidth of the third data unit; 4. The method according to any one of claims 1 to 3.
5. A protocol data unit (PPDU) transmitting device comprising a processing unit and a communication unit, The processing unit generates a first data unit; the first data unit includes at least a second data unit and a third data unit; the second data unit is used to carry a first multi-user request to transmit a first MU-RTS frame; the third data unit is used to carry a second MU-RTS frame; the first MU-RTS frame and the second MU-RTS frame use the same scrambling code initialization value; the communication unit is configured to transmit the first data unit; The end times of transmitting the first MU-RTS frame and the second MU-RTS frame are aligned; and The transport of the first MU-RTS frame and the transport of the second MU-RTS frame are aggregated into one PPDU; The MU-RTS frame indicates the bandwidth of the PPDU in the uplink bandwidth field and is transmitted in a non-HT overlapping manner; The format of the non-HT duplicate frame includes four parts: a legacy short training field, a legacy long training field, a legacy signal, and a payload. Device.
6. The first MU-RTS frame indicates a first channel on which a second device transmits a clear-to-send CTS frame; The second MU-RTS frame indicates a second channel on which a third device transmits a CTS frame; When the bandwidth of the first channel partially or completely overlaps with the bandwidth of the second channel, the first MU-RTS frame and the second MU-RTS frame use the same scrambling code initialization value.
6. The apparatus of claim 5.
7. the first data unit includes a plurality of data units; each of the plurality of data units is used to carry an MU-RTS frame; The scrambling code initialization value for all MU-RTS frames is the same, and the second data unit and the third data unit are two of the plurality of data units; 6. The apparatus of claim 5.
8. the first MU-RTS frame and the second MU-RTS frame each include a first bit sequence; and the first bit sequence indicates a bandwidth of the first data unit; or the first MU-RTS frame includes a second bit sequence; the second bit sequence indicates a bandwidth of the second data unit; the second MU-RTS frame includes a third bit sequence; and the third bit sequence indicating a bandwidth of the third data unit; 8. Apparatus according to any one of claims 5 to 7.
9. An electronic device comprising a processor and a memory. the memory is configured to store computer programs or instructions; the processor is configured to execute the computer program or the instructions in the memory; When the computer program or the instructions are executed, Implementing a method according to any one of claims 1 to 4. Electronic devices.
10. 1. A computer-readable storage medium, comprising: the computer-readable storage medium storing computer-executable instructions; When the computer-executable instructions are invoked by a computer, The computer, Implementing the method according to any one of claims 1 to 4, A computer-readable storage medium.
Citation Information
Patent Citations
Protection mechanism for multi-user transmission
US10701686B1
Protection methods for wireless transmissions
US20170104563A1
Multiple frame transmission
US20180092127A1