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WO2024260367A1 - Point d'accès d'un système à points d'accès multiples qui utilise une technique de réduction de collision de préambule pour une formation de faisceau coordonnée dans une transmission de paquet de liaison descendante et procédé de communication sans fil associé - Google Patents

Point d'accès d'un système à points d'accès multiples qui utilise une technique de réduction de collision de préambule pour une formation de faisceau coordonnée dans une transmission de paquet de liaison descendante et procédé de communication sans fil associé Download PDF

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Publication number
WO2024260367A1
WO2024260367A1 PCT/CN2024/100053 CN2024100053W WO2024260367A1 WO 2024260367 A1 WO2024260367 A1 WO 2024260367A1 CN 2024100053 W CN2024100053 W CN 2024100053W WO 2024260367 A1 WO2024260367 A1 WO 2024260367A1
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Prior art keywords
cbf
ppdu
sta
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English (en)
Inventor
Chien-Fang Hsu
Hung-Tao Hsieh
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MediaTek Inc
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MediaTek Inc
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Priority to TW113122805A priority Critical patent/TW202502084A/zh
Publication of WO2024260367A1 publication Critical patent/WO2024260367A1/fr
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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/022—Site diversity; Macro-diversity
    • H04B7/024—Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
    • H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
    • H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
    • H04B7/0617—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal for beam forming
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/02—Hierarchically pre-organised networks, e.g. paging networks, cellular networks, WLAN [Wireless Local Area Network] or WLL [Wireless Local Loop]
    • H04W84/10—Small scale networks; Flat hierarchical networks
    • H04W84/12—WLAN [Wireless Local Area Networks]

Definitions

  • the present invention relates to wireless communications, and more particularly, to an access point (AP) of a multi-AP (MAP) system that employs a preamble collision reduction technique for coordinated beamforming (CBF) in downlink packet transmission and an associated wireless communication method.
  • AP access point
  • MAP multi-AP
  • CBF coordinated beamforming
  • AP multilink devices MLDs
  • STAs non-AP stations
  • CBF coordinated beamforming
  • CBF may be employed to decrease packet decoding failure resulting from collisions at co-channel APs.
  • CBF may be implemented by using a digital precoding/filtering technique to eliminate interference between adjacent APs.
  • Each packet also called a physical layer protocol data unit (PPDU) , contains preamble and data fields.
  • PPDU physical layer protocol data unit
  • a WiFi-7 PPDU may include Non-HT Short Training field (L-STF) , Non-HT Long Training field (L-LTF) , Non-HT Signal field (L-SIG) , Repeated Non-HT Signal field (RL-SIG) , Universal Signal field (U-SIG) , EHT Signal field (EHT-SIG) , EHT Short Training field (EHT-STF) , EHT Long Training field (EHT-LTF) , Data field (EHT-Data) , and Packet Extension field (PE) .
  • L-STF Non-HT Short Training field
  • L-LTF Non-HT Signal field
  • R-SIG Repeated Non-HT Signal field
  • U-SIG Universal Signal field
  • EHT-SIG EHT Signal field
  • EHT-STF EHT Short Training field
  • EHT-LTF EHT
  • a Wi-Fi 6 PPDU may include L-STF, L-LTF, L-SIG, RL-SIG, HE Signal A field (HE-SIG-A) , HE Signal B field (HE-SIG-B) , HE Short Training field (HE-STF) , HE Long Training field (HE-LTF) , Data field (HE-Data) , and PE.
  • the precoding i.e., digital beamforming
  • a preamble of a Wi-Fi packet includes an un-precoded preamble part and a precoded preamble part, where the un-precoded preamble part may start from L-STF, and the precoded preamble part may start from EHT-STF/HE-STF.
  • the un-precoded preamble part which carries certain signal (SIG) contents, including Modulation and Coding Scheme (MCS) , resource unit (RU) allocation, etc., is subject to interference from other APs.
  • SIG signal
  • MCS Modulation and Coding Scheme
  • RU resource unit
  • One of the objectives of the claimed invention is to provide an access point (AP) of a multi-AP (MAP) system that employs a preamble collision reduction technique for coordinated beamforming (CBF) in downlink packet transmission and an associated wireless communication method.
  • AP access point
  • MAP multi-AP
  • CBF coordinated beamforming
  • an exemplary first AP of an MAP system includes a network interface circuit and a control circuit.
  • the control circuit is arranged to generate a MAC frame that carries CBF related information, and instruct the network interface circuit to transmit the MAC frame to at least one second AP of the MAP system before CBF physical layer protocol data unit (PPDU) transmission of the first AP and the at least one second AP.
  • PPDU physical layer protocol data unit
  • an exemplary wireless communication method includes: generating a MAC frame that carries CBF related information; and transmitting the MAC frame from a first AP of an MAP system to at least one second AP of the MAP system before CBF PPDU transmission of the first AP and the at least one second AP.
  • FIG. 1 is a diagram illustrating an MAP system that supports the proposed preamble collision reduction scheme according to an embodiment of the present invention.
  • FIG. 2 is a diagram illustrating a CBF topology under an SU scenario according to an embodiment of the present invention.
  • FIG. 3 is a diagram illustrating a MAC frame exchange sequence under an SU scenario according to an embodiment.
  • FIG. 4 is a diagram illustrating a first PHY design for CFB PPDU transmission with the timing error dT within +/-0.4us according to an embodiment of the present invention.
  • FIG. 5 is a diagram illustrating a second PHY design for CFB PPDU transmission with the timing error dT within +/-0.4us according to an embodiment of the present invention.
  • FIG. 6 is a diagram illustrating a third PHY design for CFB PPDU transmission with the timing error dT within +/-0.4us according to an embodiment of the present invention.
  • FIG. 7 is a diagram illustrating a fourth PHY design for CFB PPDU transmission with the timing error dT within +/-0.4us according to an embodiment of the present invention.
  • FIG. 8 is a diagram illustrating a first PHY design for CFB PPDU transmission with the timing error dT beyond +/-0.4us according to an embodiment of the present invention.
  • FIG. 9 is a diagram illustrating a second PHY design for CFB PPDU transmission with the timing error dT beyond +/-0.4us according to an embodiment of the present invention.
  • FIG. 10 is a diagram illustrating a CBF topology under an MU scenario according to an embodiment of the present invention.
  • FIG. 1 is a diagram illustrating an MAP system that supports the proposed preamble collision reduction scheme according to an embodiment of the present invention.
  • the MAP system 100 may be a Wi-Fi system compliant with IEEE 802.11ax (Wi-Fi 6) standard, IEEE 802.11be (Wi-Fi 7) standard, IEEE 802.11bn (Wi-Fi 8) standard, or a next-generation Wi-Fi standard.
  • the MAP system 100 includes a plurality of APs 102, 104_1-104_N (N ⁇ 1) .
  • the AP 102 may act as a sharing AP that shares its transmission opportunity (TXOP) with other AP (s) , and each of the APs 104_1-104_N may act as a shared AP that shares the TXOP owned by the sharing AP.
  • TXOP transmission opportunity
  • s AP
  • an AP of the MAP system 100 may be an AP MLD which owns multiple links working on different RF bands and capable of operating at the same time, or may be a non-MLD AP.
  • the MAP system 100 that supports the proposed preamble collision reduction scheme may be formed by multiple AP MLDs, multiple non-MLD APs, or a combination thereof.
  • the APs 102, 104_1-104_N may have the same or similar circuit structure.
  • the AP 102/104_1/104_N includes a processor 112/122_1/122_N, a memory 114/124_1/124_N, a control circuit 116/126_1/126_N, and a network interface circuit 117/127_1/127_N, where the network interface circuit 117/127_1/127_N includes a transmitter (TX) circuit 118/128_1/128_N and a receiver (RX) circuit 120/130_1/130_N.
  • the memory 114/124_1/124_N is arranged to store a program code.
  • the processor 112/122_1/122_N is arranged to load and execute the program code to manage the AP 102/104_1/104_N.
  • the control circuit 116/126_1/126_N is arranged to control communications with non-AP STAs and other APs.
  • control circuit 116/126_1/126_N controls the TX circuit 118/128_1/128_N of the network interface circuit 117/127_1/127_N to send packets (i.e., PPDUs) to non-AP STAs and other APs, and controls the RX circuit 120/122_1/122_N of the network interface circuit 117/127_1/127_N to receive packets (i.e., PPDUs) from non-AP STAs and other APs.
  • packets i.e., PPDUs
  • each of APs 102, 104_1-104_N may include additional components to achieve designated functions.
  • the APs 102, 104_1-104_N in the same MAP system 100 supports the proposed preamble collision reduction scheme.
  • the control circuit 116 of the AP (e.g., sharing AP) 102 is arranged to generate a MAC frame, also called a MAC protocol data unit (MPDU) , that acts as a CBF request frame CBF_REQ_0 used to carry CBF related information, and instruct the network interface circuit 117 (particularly, TX circuit 118 of network interface circuit 117) to transmit the CBF request frame CBF_REQ_0 to at least one of APs (e.g., shared APs) 104_1-104_N of the MAP system 100 before CBF PPDU transmission of sharing AP and shared AP (s) .
  • APs e.g., shared APs
  • 104_1-104_N shared AP
  • the control circuit 126_1/126_N of the AP (e.g., shared AP) 104_1/104_N is arranged to generate a MAC frame that acts as a CBF response frame CBF_RSP_1/CBF_RSP_N used to carry CBF related information, and instruct the network interface circuit 127_1/127_N (particularly, TX circuit 128_1/128_N of network interface circuit 127_1/127_N) to transmit the CBF response frame CBF_RSP_1/CBF_RSP_N to the AP (e.g., sharing AP) 102 before CBF PPDU transmission of sharing AP and shared AP (s) .
  • the AP e.g., sharing AP
  • FIG. 2 is a diagram illustrating a CBF topology under an SU scenario according to an embodiment of the present invention.
  • One non-AP STA (labeled by “STA1” ) is associated to one AP (labeled by “AP1” ) of one cell (labeled by “Cell A” )
  • another non-AP STA (labeled by “STA2” ) is associated to another AP (labeled by “AP2” ) of another cell (labeled by “Cell B” )
  • the AP (AP1) transmits an SU PPDU to a single non-AP STA (STA1)
  • the AP (AP2) transmits an SU PPDU to a single non-AP STA (STA2) .
  • FIG. 3 is a diagram illustrating a MAC frame exchange sequence under an SU scenario according to an embodiment.
  • One AP may be a sharing AP
  • another AP AP2
  • the sharing AP AP1
  • the sharing AP AP1
  • CBF_REQ which is a MAC frame that carries CBF related information INF1
  • the shared AP In response to receiving the CBF request frame CBF_REQ, the shared AP (AP2) generates a CBF response frame CBF_RSP (which is a MAC frame that carries CBF related information INF2) , and transmits the CBF response frame CBF_RSP to the sharing AP (AP1) .
  • CBF_RSP which is a MAC frame that carries CBF related information INF2
  • the sharing AP transmits a CBF PPDU (labeled by “CBF PPDU1” ) to its target non-AP STA (STA1) , and receives a block acknowledgement (BA) frame from the target non-AP STA (STA1)
  • the shared AP transmits a CBF PPDU (labeled by “CBF PPDU2” ) to its target non-AP STA (STA2) , and receives a BA frame from the target non-AP STA (STA2) .
  • the sharing AP may be the AP 102 shown in FIG. 1
  • the shared AP may be one of the APs 104_1-104_N shown in FIG. 1.
  • CBF related information INF1 is carried by the CBF request frame CBF_REQ (e.g., CBF_REQ_0) .
  • the sharing AP AP1 transmits the CBF request frame CBF_REQ for controlling a starting time T2 of a CBF PPDU (labeled by “CBF PPDU2” ) to be transmitted from the shared AP (AP2) to its target non-AP STA (STA2) .
  • the CBF related information INF1 carried by the CBF request frame CBF_REQ may be indicative of the starting time T2 of the CBF PPDU (labeled by “CBF PPDU2” ) to be transmitted from the shared AP (AP2) to its target non-AP STA (STA2) .
  • SIFS Short Interframe Space
  • the starting time T2 of AP2’s CBF PPDU depends on transmission timing of the CBF request frame CBF_REQ sent from the sharing AP (AP1) .
  • the shared AP AP2 is informed of the starting time T2 of AP2’s CBF PPDU (labeled by “CBF PPDU2” ) upon reception of the CBF request frame CBF_REQ.
  • the CBF related information INF1 carried by the CBF request frame CBF_REQ may be indicative of synchronized preamble signal (SIG) contents that are decided by the sharing AP (AP1) .
  • SIG synchronized preamble signal
  • the synchronized preamble SIG contents may be the same SIG contents to be transmitted by Non-HT parts of different APs’ CBF PPDUs to ensure each CBF PPSU has the same Non-HT part.
  • the CBF related information INF1 may directly carry required SIG contents.
  • the CBF related information INF1 may carry a simple predefined indication rather than the required SIG contents, where the simple predefined indication may indicate to select the required SIG contents from pre-defined SIG content candidates.
  • the shared AP AP2 is informed of the synchronized preamble SIG contents indicated by the CBF request frame CBF_REQ.
  • the CBF request frame CBF_REQ may also serve as a SIG content carrier for non-AP STAs associated to the sharing AP (AP1) and the shared AP (AP2) .
  • the CBF request frame CBF_REQ (which carries the CBF related information INF1 indicative of synchronized preamble SIG contents) is transmit to the shared AP (AP2) as well as the target non-AP STAs (STA1 and STA2) of sharing AP (AP1) and the shared AP (AP2) .
  • the non-AP STAs (STA1 and STA2) are also informed of the same synchronized preamble SIG contents decided by the sharing AP (AP1) .
  • the CBF related information INF1 carried by the CBF request frame CBF_REQ may be indicative of an allowed bandwidth of a CBF PPDU to be transmitted from the shared AP (AP2) to its target non-AP STA (STA2) , if partial bandwidth can be used.
  • the CBF related information INF1 carried by the CBF request frame CBF_REQ may be indicative an identifier (ID) of the target non-AP STA (STA1) of the sharing AP (AP1) , where the ID of the non-AP STA (STA1) may be referenced for setting a precoder included in a control circuit of the shared AP (AP2) .
  • ID of the non-AP STA (STA1) may be an association ID (AID) or a universal ID in the MAP system 100.
  • the CBF related information INF1 carried by the CBF request frame CBF_REQ may be indicative of one or more preferred non-AP STA candidates associated to the shared AP (AP2) .
  • the CBF related information INF1 may include a list consisting of multiple STAs’A IDs or other IDs, and the shared AP (AP2) picks up one of the STAs on the list as the target non-AP STA (STA2) to which AP2’s CBF PPDU (labeled by “CBF PPDU2” ) should be sent.
  • the CBF related information INF1 carried by the CBF request frame CBF_REQ may be indicative of a length of a CBF PPDU (which is labeled by “CBF PPDU1” ) to be transmitted from the sharing AP (AP1) to its target non-AP STA (STA1) , or an ending time of the CBF PPDU (which is labeled by “CBF PPDU1” ) to be transmitted from the sharing AP (AP1) to its target non-AP STA (STA1) .
  • the CBF related information INF1 carried by the CBF request frame CBF_REQ may be indicative of a beam change setting (i.e., a value of a beam change field) included in a CBF PPDU (which is labeled by “CBF PPDU1” ) to be transmitted from the sharing AP (AP1) to its target non-AP STA (STA1) .
  • a beam change field is set by “1”
  • it implies that a preamble of the CBF PPDU (which is labeled by “CBF PPDU1” ) includes an un-precoded preamble part and a precoded preamble part.
  • the un-precoded preamble part starts from L-STF
  • the precoded preamble part starts from EHT-STF/HE-STF.
  • the beam change field is set by “0”
  • the whole preamble of the CBF PPDU (which is labeled by “CBF PPDU1” ) is precoded.
  • the sharing AP AP1 transmits the CBF PPDU (which is labeled by “CBF PPDU1” ) with a precoded preamble part and without an un-precoded preamble part.
  • CBF related information INF2 is carried by the CBF response frame CBF_RSP (e.g., CBF_RSP_1 or CBF_RSP_N) that is generated in response to the CBF request frame CBF_REQ (e.g., CBF_REQ_0) .
  • the CBF related information INF2 set by the shared AP (AP2) may be indicative of whether a CBF request of the sharing AP (AP1) is rejected or accepted.
  • the CBF related information INF2 carried by the CBF response frame CBF_RSP may be indicative of synchronized preamble signal (SIG) contents that are decided by the shared AP (AP2) .
  • the CBF related information INF2 may directly carry required SIG contents.
  • the CBF related information INF2 may carry a simple predefined indication rather than the required SIG contents, where the simple predefined indication may indicate to select the required SIG contents from pre-defined SIG content candidates.
  • the shared AP (AP2) can inform the sharing AP (AP1) of its preferred synchronized preamble SIG contents through the CBF related information INF2 carried by the CBF response frame CBF_RSP, such that the same synchronized preamble SIG contents can be used by both of the sharing AP (AP1) and the shared AP (AP2) during CBF PPDU transmission.
  • the shared AP can inform the sharing AP (AP1) of synchronized preamble SIG contents through the CBF related information INF2 carried by the CBF response frame CBF_RSP, such that the same synchronized preamble SIG contents can be used by both of the sharing AP (AP1) and the shared AP (AP2) during CBF PPDU transmission.
  • the sharing AP (AP1) is informed of the synchronized preamble SIG contents indicated by the CBF response frame CBF_RSP, and adopts the synchronized preamble SIG contents decided by the shared AP (AP2) .
  • the CBF response frame CBF_RSP may also serve as a SIG content carrier for target non-AP STAs (STA1 and STA2) of sharing AP (AP1) and shared AP (AP2) .
  • the CBF response frame CBF_RSP (which carries the CBF related information INF2 indicative of synchronized preamble SIG contents) is encapsulated in a PPDU with an MU PPDU format, and is transmit to the sharing AP (AP2) as well as the non-AP STAs (STA1 and STA2) .
  • the non-AP STAs (STA1 and STA2) are also informed of the same synchronized preamble SIG contents decided by the shared AP (AP2) .
  • the CBF related information INF2 carried by the CBF response frame CBF_RSP may be indicative of a bandwidth of a CBF PPDU (labeled by CBF PPDU2) to be transmitted from the shared AP (AP2) to its target non-AP STA (STA2) , if partial bandwidth can be used.
  • a narrower bandwidth can be indicated by the CBF related information INF2 included in the CBF response frame CBF_RSP.
  • the CBF related information INF2 carried by the CBF response frame CBF_RSP may be indicative an ID of the target non-AP STA (STA2) of the shared AP (AP2) , where the ID of the non-AP STA (STA2) may be referenced for setting a precoder included in a control circuit of the sharing AP (AP1) .
  • the ID of the non-AP STA (STA2) may be an AID or a universal ID in the MAP system 100. It should be noted that the non-AP STA (STA2) cannot enter a power save (PS) mode if its AID is indicated by the CBF related information INF2 of the CBF response frame CBF_RSP.
  • the shared AP (AP2) After receiving the CBF request frame CBF_REQ sent from the sharing AP (AP1) , the shared AP (AP2) needs to parse information included in the CBF request frame CBF_REQ. Similarly, after receiving the CBF response frame CBF_RSP sent from the shared AP (AP2) , the sharing AP (AP1) needs to parse information included in the CBF response frame CBF_RSP. In some embodiments of the present invention, necessary padding may be added to the CBF request frame CBF_REQ to allow processing latency at the shared AP (AP2) , and/or necessary padding may be added to the CBF response frame CBF_RSP to allow processing latency at the sharing AP (AP1) .
  • the preceding MAC frame exchange sequence can provide useful information to facilitate preamble collision reduction of the following CBF PPDU transmission.
  • the control circuit 116 of the AP (e.g., sharing AP) 102 obtains the CBF response frame CBF_RSP_1/CBF_RSP_N via the network interface circuit 117 (particularly, RX circuit 120 of network interface circuit 117) and the control circuit 126_1/126_N of the AP (e.g., shared AP) 104_1/104_N obtains the CBF request frame CBF_REQ_0 via the network interface circuit 127_1/127_N (particularly, RX circuit 130_1/130_N of network interface circuit 127_1/127_N) , the AP (e.g., sharing AP) 102 and the AP (e.g., shared AP) 104_1/104_N start CBF PPDU transmission.
  • the control circuit 116 of the AP (e.g., sharing AP) 102 generates a CBF PPDU (i.e., TX packet) CBF_PKT_0, and instructs the network interface circuit 117 (particularly, TX circuit 118 of network interface circuit 117) to transmit the CBF PPDU (i.e., TX packet) CBF_PKT_0 to a target non-AP STA associated to the AP (e.g., sharing AP) 102 under an SU scenario.
  • control circuit 126_1/126_N of the AP e.g., shared AP
  • the control circuit 126_1/126_N of the AP e.g., shared AP
  • the control circuit 126_1/126_N of the AP e.g., shared AP
  • the control circuit 126_1/126_N of the AP e.g., shared AP
  • the control circuit 126_1/126_N of the AP e.g., shared AP
  • the control circuit 126_1/126_N of the AP e.g., shared AP
  • the control circuit 126_1/126_N of the AP e.g., shared AP
  • the control circuit 126_1/126_N of the AP e.g., shared AP
  • the control circuit 126_1/126_N of the AP e.g., shared AP
  • the control circuit 126_1/126_N of the AP e.g., shared AP
  • transmission of sharing AP’s CBF PPDU and transmission of shared AP’s CBF PPDU may be synchronous, such that a timing error between a starting time of a CBF PPDU transmitted by the sharing AP and a starting time of a CBF PPDU transmitted by the shared AP is within a pre-defined timing error tolerance such as +/-0.4 us as specified in the Wi-Fi specification.
  • a pre-defined timing error tolerance such as +/-0.4 us as specified in the Wi-Fi specification.
  • synchronous transmission of AP1’s CBF PPDU (labeled by “CBF PPDU1” ) and AP2’s CBF PPDU (labeled by “CBF PPDU2” ) happens under a condition that the timing error dT is within the pre-defined timing error tolerance.
  • transmission of sharing AP’s CBF PPDU and transmission of shared AP’s CBF PPDU may be asynchronous, such that a timing error between a starting time of a CBF PPDU transmitted by the sharing AP and a starting time of a CBF PPDU transmitted by the shared AP is beyond a pre-defined timing error tolerance such as +/-0.4us as specified in the Wi-Fi specification. As shown in FIG.
  • the present invention proposes several PHY designs directed to preamble collision reduction of CFB PPDU transmission.
  • preamble alignment may be 80MHz based
  • the PPDU may be an aggregated PPDU (A-PPDU)
  • different APs may have different bandwidth.
  • A-PPDU aggregated PPDU
  • these are for illustrative purposes only, and are not meant to be limitations of the present invention.
  • one non-AP STA is associated to one sharing AP (AP1) under the SU scenario
  • another non-AP STA is associated to the shared AP (AP2) under the SU scenario
  • the sharing AP may be the AP 102 shown in FIG. 1
  • the shared AP may be one of the APs 104_1-104_N shown in FIG. 1.
  • FIG. 4 is a diagram illustrating a first PHY design for CFB PPDU transmission with the timing error dT within +/-0.4us according to an embodiment of the present invention.
  • the non-AP STAs (STA1 and STA2) are informed of same synchronized preamble SIG contents during the MAC frame exchange sequence.
  • CBF PPDU timing synchronization is achieved through a CBF request frame (e.g., CBF_REQ_0) that is generated from the sharing AP (AP1) and controls a starting time of the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) generated from the shared AP (AP2) .
  • the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) should be transmitted after SIFS of a PPDU carrying the CBF response frame (e.g., CBF_RSP_1/CBF_RSP_N) that is generated in response to the CBF request frame (e.g., CBF_REQ_0) .
  • the CBF PPDU (e.g., CBF_PKT_0) generated from the sharing AP (AP1) has a precoded preamble part 404 and an un-precoded preamble part 402.
  • the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) generated from the shared AP (AP2) also has a precoded preamble part 404 and an un-precoded preamble part 402.
  • the preamble collision between AP1’s CBF PPDU (e.g., CBF_PKT_0) and AP2’s CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) does not affect packet decoding at the target non-AP STAs (STA1 and STA2) of sharing AP (AP1) and shared AP (AP2) .
  • FIG. 5 is a diagram illustrating a second PHY design for CFB PPDU transmission with the timing error dT within +/-0.4us according to an embodiment of the present invention.
  • CBF PPDU timing synchronization is achieved through a CBF request frame that is generated from the sharing AP (AP1) and controls a starting time of the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) generated from the shared AP (AP2) .
  • the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) should be transmitted after SIFS of a PPDU carrying the CBF response frame (e.g., CBF_RSP_1/CBF_RSP_N) that is generated in response to the CBF request frame (e.g., CBF_REQ_0) .
  • a new precoding-protected SIG field 501 is used to indicate the important information, including MCS, number of spatial streams (NSS) , RU allocation, etc.
  • the CBF PPDU (e.g., CBF_PKT_0) generated from the sharing AP (AP1) has a precoded preamble part 504 and an un-precoded preamble part 502, where SIG contents decided by the sharing AP (AP1) are recorded in the SIG field 501, and carried by the precoded preamble part 504.
  • the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) generated from the shared AP (AP2) also has a precoded preamble part 504 and an un-precoded preamble part 502, where SIG contents decided by the shared AP (AP2) are recorded in the SIG field 501, and carried by the precoded preamble part 504.
  • the preamble collision between AP1’s CBF PPDU (e.g., CBF_PKT_0) and AP2’s CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) does not affect packet decoding at the target non-AP STAs (STA1 and STA2) of sharing AP (AP1) and shared AP (AP2) .
  • FIG. 6 is a diagram illustrating a third PHY design for CFB PPDU transmission with the timing error dT within +/-0.4us according to an embodiment of the present invention.
  • the same synchronized preamble SIG contents are confirmed by the sharing AP (AP1) and the shared AP (AP2) during the MAC frame exchange sequence, where the synchronized preamble SIG may be set by the sharing AP (AP1) or the shared AP (AP2) .
  • CBF PPDU timing synchronization is achieved through a CBF request frame (e.g., CBF_REQ_0) that is generated from the sharing AP (AP1) and controls a starting time of the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) generated from the shared AP (AP2) .
  • the CBF PPDU e.g., CBF_PKT_1/CBF_PKT_N
  • the CBF PPDU (e.g., CBF_PKT_0) generated from the sharing AP (AP1) has a precoded preamble part 604 and an un-precoded preamble part 602, where the synchronized preamble SIG contents are carried by the un-precoded preamble part 602.
  • the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) generated from the shared AP (AP2) also has a precoded preamble part 604 and an un-precoded preamble part 602, where the synchronized preamble SIG contents are carried by the un-precoded preamble part 602.
  • the same synchronized preamble SIG contents are not precoding-protected in each of the CBF PPDU (e.g., CBF_PKT_0) generated from the sharing AP (AP1) and the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) generated from the shared AP (AP2) .
  • the preamble collision between AP1’s CBF PPDU (e.g., CBF_PKT_0) and AP2’s CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) does not affect packet decoding at target non-AP STAs (STA1 and STA2) of sharing AP (AP) and shared AP (AP2) .
  • FIG. 7 is a diagram illustrating a fourth PHY design for CFB PPDU transmission with the timing error dT within +/-0.4us according to an embodiment of the present invention.
  • CBF PPDU timing synchronization is achieved through a CBF request frame (e.g., CBF_REQ_0) that is generated from the sharing AP (AP1) and controls a starting time of the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) generated from the shared AP (AP2) .
  • the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) should be transmitted after SIFS of a PPDU carrying the CBF response frame (e.g., CBF_RSP_1/CBF_RSP_N) that is generated in response to the CBF request frame (e.g., CBF_REQ_0) .
  • both of the sharing AP (AP1) and the shared AP (AP2) apply precoding to the whole preamble in one PPDU.
  • the CBF PPDU (e.g., CBF_PKT_0) generated from the sharing AP (AP1) has a precoded preamble part 702 and has no un-precoded preamble part
  • the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) generated from the shared AP (AP2) has a precoded preamble part 702 and has no un-precoded preamble part.
  • CBF_PKT_0 CBF_PKT_0
  • AP2 CBF PPDU
  • CBF_PKT_1/CBF_PKT_N target non-AP STAs
  • FIG. 8 is a diagram illustrating a first PHY design for CFB PPDU transmission with the timing error dT beyond +/-0.4us according to an embodiment of the present invention.
  • a starting time of a later AP’s CBF PPDU is controlled by the sharing AP (AP1) during the MAC frame exchange sequence.
  • the CBF related information carried by the CBF request frame e.g., CBF_REQ_0
  • the CBF request frame e.g., CBF_REQ_0
  • the CBF_PKT_1/CBF_PKT_N is indicative of the starting time of the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) to be transmitted by the shared AP (AP2) .
  • the CBF PPDU (e.g., CBF_PKT_0) generated from the sharing AP (AP1) has a precoded preamble part 804 and an un-precoded preamble part 802.
  • the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) generated from the shared AP (AP2) also has a precoded preamble part 804 and an un-precoded preamble part 802.
  • the asynchronous transmission of AP1’s CBF PPDU and AP2’s CBF PPDU can protect a portion of AP1’s CBF PPDU from being interfered with the AP2’s CBF PPDU.
  • the starting time of the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) transmitted by the shared AP (AP2) is properly controlled to ensure that the preamble and the first MPDU of AP1’s CBF PPDU are not interfered with AP2’s CBF PPDU.
  • CBF_PKT_1/CBF_PKT_N the shared AP
  • the CBF PPDU (e.g., CBF_PPDU_0) transmitted from the sharing AP (AP1) includes a first segment S1 and a second segment S2 following the first segment S1, a period in which the first segment S1 is transmitted does not overlap a period in which the CBF PPDU (e.g., CBF_PPDU_1/CBF_PPDU_N) is transmitted by the shared AP (AP2) , a period in which the second segment S2 is transmitted overlaps the period in which the CBF PPDU (e.g., CBF_PPDU_1/CBF_PPDU_N) is transmitted by the shared AP (AP2) , and a preamble and a first MPDU are carried by the first segment S1.
  • the CBF PPDU e.g., CBF_PPDU_0
  • an RX circuit of the non-AP STA may erroneously switch from receiving AP1’s CBF PPDU to receiving AP2’s CBF PPDU.
  • the present invention proposes controlling the starting time of AP2’s CBF PPDU to ensure that decoding of the first MPDU included in AP1’s CBF PPDU is protected from being interfered with AP2’s CBF PPDU.
  • FIG. 9 is a diagram illustrating a second PHY design for CFB PPDU transmission with the timing error dT beyond +/-0.4us according to an embodiment of the present invention.
  • a starting time of a later AP’s CBF PPDU is controlled by the sharing AP (AP1) during the MAC frame exchange sequence.
  • the CBF related information carried by the CBF request frame e.g., CBF_REQ_0
  • the CBF request frame e.g., CBF_REQ_0
  • the CBF_PKT_1/CBF_PKT_N is indicative of the starting time of the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) to be transmitted by the shared AP (AP2) .
  • the CBF PPDU (e.g., CBF_PKT_0) generated from the sharing AP (AP1) has a precoded preamble part 804 and an un-precoded preamble part 802.
  • the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) generated from the shared AP (AP2) also has a precoded preamble part 804 and an un-precoded preamble part 802.
  • both of the sharing AP (AP1) and the shared AP (AP2) apply precoding to the whole preamble in one PPDU.
  • the CBF PPDU (e.g., CBF_PKT_0) generated from the sharing AP (AP1) has a precoded preamble part 902 and has no un-precoded preamble part
  • the CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) generated from the shared AP (AP2) has a precoded preamble part 902 and has no un-precoded preamble part.
  • preamble collision between AP1’s CBF PPDU (e.g., CBF_PKT_0) and AP2’s CBF PPDU (e.g., CBF_PKT_1/CBF_PKT_N) does not affect packet decoding at target non-AP STAs (STA1 and STA2) of sharing AP (AP1) and shared AP (AP2) .
  • PPDU formats shown in FIGs. 4-9 are for illustrative purposes only, and are not meant to be limitations of the present invention. In practice, the PPDU format may be adjusted, depending upon the Wi-Fi specification.
  • the proposed MAC frame exchange sequence and PHY designs are illustrated under an SU scenario.
  • this is for illustrative purposes only, and is not meant to be a limitation of the present invention.
  • the same preamble collision reduction concept is applicable to an MU scenario.
  • FIG. 10 is a diagram illustrating a CBF topology under an MU scenario according to an embodiment of the present invention.
  • Multiple non-AP STAs (labeled by “STA11” and “STA12” ) are associated to one AP (labeled by “AP1” ) in one cell (labeled by “Cell A” )
  • one non-AP STA (labeled by “STA2” ) is associated to another AP (labeled by “AP2” ) in another cell (labeled by “Cell B” )
  • one non-AP STA (labeled by “STA3” ) is associated to yet another AP (labeled by “AP3” ) in yet another cell (labeled by “Cell C” ) .
  • multiple APs join the CBF AP group; and the sharing AP (AP1) transmits an MU PPDU to multiple non-AP STAs (STA11 &STA 12) , and transmits a CBF request frame to multiple shared APs (AP2 &AP3) .
  • the sharing AP AP1 transmits an MU PPDU to multiple non-AP STAs (STA11 &STA 12) , and transmits a CBF request frame to multiple shared APs (AP2 &AP3) .
  • more than one non-AP STA may be associated to the shared AP (AP2)
  • more than one non-AP STA may be associated to the shared AP (AP3) .
  • the shared AP (AP2) may transmit an MU PPDU to multiple non-AP STAs
  • the shared AP (AP3) may transmit an MU PPDU to multiple non-AP STAs.
  • the sharing AP may be the AP 102 shown in FIG. 1, and the shared APs (AP2 &AP3) may be APs 104_1 and 104_N shown in FIG. 1.
  • the control circuit 116 of the AP e.g., sharing AP
  • the network interface circuit 117 particularly, TX circuit 118 of network interface circuit 117
  • the network interface circuit 117 to transmit the CBF request frame CBF_REQ_0 to multiple APs (e.g., shared APs) 104_1, 104_N of the MAP system 100 before CBF PPDU transmission of the sharing AP and shared APs.
  • the CBF related information carried by the CBF request frame CBF_REQ_0 may be indicative of synchronized preamble SIG contents shared by APs 102, 104_1, 104_N, starting time information of CBF PPDUs to be transmitted by APs 104_1, 104_N, allowed bandwidths of CBF PPDUs to be transmitted by APs 104_1, 104_N, IDs of target non-AP STAs (STA11 &STA12) of AP 102, preferred non-AP STA candidates associated to APs 104_1, 104_N, a length of a CBF PPDU to be transmitted by AP 102, ending time of a CBF PPDU to be transmitted by AP 102, and/or beam change setting included in a CBF PPDU to be transmitted by AP 102.
  • the control circuit 126_1 of the AP e.g., shared AP
  • the control circuit 126_1 of the AP 104_1 is arranged to generate a CBF response frame CBF_RSP_1 used to carry CBF related information, and instruct the network interface circuit 127_1 (particularly, TX circuit 128_1 of network interface circuit 127_1) to transmit the CBF response frame CBF_RSP_1 to the AP (e.g., sharing AP) 102 before CBF PPDU transmission of the sharing AP and shared APs
  • the control circuit 126_N of the AP e.g., shared AP
  • the control circuit 126_N of the AP e.g., shared AP
  • the control circuit 126_N of the AP e.g., shared AP
  • the control circuit 126_N of the AP e.g., shared AP
  • the control circuit 126_N of the AP e.g., shared AP

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  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
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Abstract

Un premier point d'accès (AP) d'un système multi-AP (MAP) comprend un circuit d'interface réseau et un circuit de commande. Le circuit de commande génère une trame de commande d'accès au support (MAC) qui transporte des informations associées à la formation de faisceau coordonnée (CBF), et donne l'instruction au circuit d'interface réseau de transmettre la trame MAC à au moins un second AP du système MAP avant la transmission d'unité de données de protocole de couche physique CBF (PPDU) du premier AP et dudit au moins un second AP.
PCT/CN2024/100053 2023-06-20 2024-06-19 Point d'accès d'un système à points d'accès multiples qui utilise une technique de réduction de collision de préambule pour une formation de faisceau coordonnée dans une transmission de paquet de liaison descendante et procédé de communication sans fil associé Pending WO2024260367A1 (fr)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20140362840A1 (en) * 2013-06-07 2014-12-11 Broadcom Corporation Inter-AP coordination and synchronization within wireless communications
WO2015081567A1 (fr) * 2013-12-06 2015-06-11 华为技术有限公司 Procédé, dispositif et système de point d'accès de dispositif de station
WO2020231062A1 (fr) * 2019-05-10 2020-11-19 엘지전자 주식회사 Maintien de liaison dans un système à ap multiples
CN113747485A (zh) * 2020-05-30 2021-12-03 华为技术有限公司 多ap协作传输的信道探测方法及相关装置
CN113973512A (zh) * 2019-05-07 2022-01-25 华为技术有限公司 用于极高吞吐量探测过程指示的系统和方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20140362840A1 (en) * 2013-06-07 2014-12-11 Broadcom Corporation Inter-AP coordination and synchronization within wireless communications
WO2015081567A1 (fr) * 2013-12-06 2015-06-11 华为技术有限公司 Procédé, dispositif et système de point d'accès de dispositif de station
CN113973512A (zh) * 2019-05-07 2022-01-25 华为技术有限公司 用于极高吞吐量探测过程指示的系统和方法
WO2020231062A1 (fr) * 2019-05-10 2020-11-19 엘지전자 주식회사 Maintien de liaison dans un système à ap multiples
CN113747485A (zh) * 2020-05-30 2021-12-03 华为技术有限公司 多ap协作传输的信道探测方法及相关装置

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
MOTOROLA: "Coordinated Beamforming Algorithms Based on Spatial Covariance Feedback and its Gain over Single-point SU/MU Beamforming", 3GPP DRAFT; R1-093410 SCF BASED COBF AND RESULTS, 3RD GENERATION PARTNERSHIP PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, no. Shenzhen, China; 20090819, 19 August 2009 (2009-08-19), Mobile Competence Centre ; 650, route des Lucioles ; F-06921 Sophia-Antipolis Cedex ; France , XP050351699 *

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