An access point and method to enable coordinated operation in multi-access point communication network

Abstract

The present disclosure relates to method and Access Point (AP) (303a) for enabling coordinated operation in Multi-Access Point (MAP) communication network (301). The method comprises broadcasting Null Data Packet Announcement (NDPA) (413), in which NDPA (413) comprises primary information elements (IEs). The method then includes transmitting Null Data Packet (NDP) (415) to station (305), to enable station (305) to determine Channel State Information (CSI), based on transmitted NDP (415). Further, the method includes broadcasting sounding report request (417), based on transmitted NDP (415), in which sounding report request (417) comprises secondary IEs corresponding to sounding operation. The station (305) is configured to transmit sounding report (419) to the at least one AP (303a), based on sounding report request (417). Furthermore, the method comprises determining signal transmission actions for performing coordinated operation, based on sounding report (419). The sounding report (419) is shared between plurality of APs (303).

Description

AN ACCESS POINT AND METHOD TO ENABLE COORDINATED OPERATION IN MULTI-ACCESS POINT COMMUNICATION NETWORK

[0001] The present disclosure generally relates to wireless communications, in particular, but not exclusively to a method and an Access Point (AP) for enabling coordinated operation in a Multi-Access Point (MAP) communication network.

[0002] Wireless Local Area Networks (WLANs) have evolved continuously during the past two decades in order to offer high data rates at lower costs. In general, beamforming is a technology that enhances signal strength and lowers interference by directing wireless signals towards particular devices. Coordination of beamforming helps improve wireless communication in a Multi-Access Point (MAP) WLAN network by enabling cooperation between numerous Access Points (APs).

[0003] Sounding operation for beamforming was first introduced in one of the IEEE standards such as 802.11n (Wi-Fi 4). The Wi-Fi 4 has introduced Multiple Input Multiple Output (MIMO) techniques to transmit multiple data streams simultaneously. To make MIMO more efficient, sounding is required to estimate the quality of the wireless channel such as Channel State Information (CSI) to optimize transmission. Further, sounding became more important in the latter versions of Wi-Fi such as Wi-Fi 5 (IEEE 802.11ac), Wi-Fi 6 (IEEE 802.11ax) and Wi-Fi 7 (IEEE 802.11be) while considering advanced features like multiuser MIMO and beamforming, which requires more precise channel estimates via sounding.

[0004] In the MAP WLAN network, multiple Stations (STAs) are connected with multiple APs, which leads to interference, leading to latency issues.

[0005] In view of the above, there is a need for a system to address above-mentioned one or more problems.

[0006] The information disclosed in this background of the disclosure section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

[0007] In an embodiment the present disclosure provides a method and an Access Point (AP) for enabling a coordinated operation in a Multi-Access Point (MAP) communication network.

[0008] In an embodiment, the method comprises broadcasting, by at least one Access Point (AP) from a plurality of Access Points (APs) present in a Multi-Access Point (MAP) communication network, a Null Data Packet Announcement (NDPA), in which the NDPA comprises one or more primary information elements, corresponding to a sounding operation. In an embodiment, the NDPA is available to the plurality of APs, and a station. The method then includes transmitting, by the at least one AP, a Null Data Packet (NDP) to the station, to enable the station to determine a Channel State Information (CSI), based on the transmitted NDP. Further, the method includes broadcasting, by the at least one AP, a sounding report request, based on the transmitted NDP, in which the sounding report request comprises one or more secondary information elements corresponding to the sounding operation. In an embodiment, the sounding report request is available to the plurality of APs, and the station. Further, in an embodiment, the station is configured to transmit a sounding report to the at least one AP, based on the sounding report request. Furthermore, the method comprises determining, by the at least one AP, one or more signal transmission actions for performing a coordinated operation, based on the sounding report. In an embodiment, the sounding report is shared between the plurality of APs.

[0009] In an embodiment, the AP comprises a processor and a memory coupled with the processor. The processor is configured to broadcast a Null Data Packet Announcement (NDPA), in which the NDPA comprises one or more primary information elements, corresponding to a sounding operation. In an embodiment, the NDPA is available to a plurality of APs, and a station. The processor is further configured to transmit a Null Data Packet (NDP) to the station, to enable the station to determine a Channel State Information (CSI), based on the transmitted NDP. Further, the processor is configured to broadcast a sounding report request, based on the transmitted NDP, in which the sounding report request comprises one or more secondary information elements corresponding to the sounding operation. In an embodiment, the sounding report request is available to the plurality of APs, and the station. Further, in an embodiment, the station is configured to transmit a sounding report to the at least one AP, based on the sounding report request. Furthermore, the processor is configured to determine one or more signal transmission actions for performing a coordinated operation, based on the sounding report. In an embodiment, the sounding report is shared between the plurality of APs.

[0010] Another aspect of the present disclosure provides a method and a station for enabling a coordinated operation in a Multi-Access Point (MAP) communication network.

[0011] In an embodiment, the method comprises receiving, by a station, a Null Data Packet Announcement (NDPA) broadcasted by the at least one Access Point (AP) from a plurality of APs present in a Multi-Access Point (MAP) communication network, in which the NDPA comprises one or more primary information elements corresponding to a sounding operation. In an embodiment, the NDPA is available to the plurality of APs, and the station. The method then includes receiving, by the station, a Null Data Packet (NDP) from the at least one AP to determine a Channel State Information (CSI). Further, the method includes receiving, by the station, a sounding report request broadcasted by the at least one AP, based on the received NDP, in which the sounding report request comprises one or more secondary information elements corresponding to the sounding operation. In an embodiment, the sounding report request is available to the plurality of APs, and the station. Furthermore, the method includes generating, by the station, a sounding report, based on the sounding report request and transmitting the sounding report to the at least one AP for enabling the coordinated operation in the MAP communication network.

[0012] In an embodiment, the station comprises a processor and a memory coupled with the processor. The processor is configured to receive a Null Data Packet Announcement (NDPA) broadcasted by at least one Access Point (AP) from a plurality of APs present in a Multi-Access Point (MAP) communication network, in which the NDPA comprises one or more primary information elements corresponding to a sounding operation. In an embodiment, the NDPA is available to the plurality of APs, and a station. The processor is further configured to receive a Null Data Packet (NDP) from the at least one AP to determine a Channel State Information (CSI). Further, the processor is configured to receive a sounding report request broadcasted by the at least one AP, based on the received NDP, in which the sounding report request comprises one or more secondary information elements corresponding to the sounding operation. In an embodiment, the sounding report request is available to the plurality of APs, and the station. Furthermore, the processor is configured to generate a sounding report, based on the sounding report request and transmitting the sounding report to the at least one AP for enabling the coordinated operation in the MAP communication network.

[0013] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

[0014] The present disclosure proposes a method and system to enable sounding operation for Co-ordinated Beamforming in Multi-AP WLAN Network.

[0015] The present disclosure helps manage interference and ensures more efficient and reliable wireless communication.

[0016] The present disclosure facilitates aligning of carrier frequency and improves coordination for beamforming.

[0017] The present disclosure performs better utilization of spectrum, thus increasing spectral efficiency. Further, the present disclosure helps in creating nulls, thus mitigating interference of signals.

[0018] The embodiments of the disclosure itself, as well as a preferred mode of use, further objectives, and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings. One or more embodiments are now described, by way of example only, with reference to the accompanying drawings in which:

[0019] FIG. 1 illustrates a data flow representation of a conventional implicit sounding, in accordance with the conventional technology.

[0020] FIG. 2 illustrates a data flow representation of a conventional explicit sounding, in accordance with the conventional technology.

[0021] FIG. 3 illustrates an exemplary environment for enabling a coordinated operation in a Multi-Access Point (MAP) communication network, in accordance with some embodiments of the present disclosure;

[0022] FIG. 4 illustrates a block diagram of at least one AP, in accordance with some embodiments of the present disclosure;

[0023] FIG. 5 illustrates a block diagram of a station, in accordance with some embodiments of the present disclosure;

[0024] FIGs. 6a and 6b illustrates a scenario representation of enabling a coordinated operation in a Multi-Access Point (MAP) communication network when the type of sounding corresponds to a sequential sounding, in accordance with some embodiments of the present disclosure;

[0025] FIG. 7 illustrates a scenario representation of enabling a coordinated operation in a Multi-Access Point (MAP) communication network when the type of sounding corresponds to a joint sounding, in accordance with some embodiments of the present disclosure;

[0026] FIG. 8 illustrates a scenario representation of sharing the sounding report for enabling a coordinated operation in a Multi-Access Point (MAP) communication network, in accordance with some embodiments of the present disclosure;

[0027] FIG. 9 illustrates a scenario representation of performing the coordinated operation, based on determined agreement between at least one AP and the plurality of APs, in accordance with some embodiments of the present disclosure;

[0028] FIG. 10 illustrates a flowchart representation of a method of enabling a coordinated operation in a Multi-Access Point (MAP) communication network by at least one AP, in accordance with some embodiments of the present disclosure; and

[0029] FIG. 11 illustrates a flowchart representation of a method of enabling a coordinated operation in a Multi-Access Point (MAP) communication network by a station, in accordance with some embodiments of the present disclosure.

[0030] It should be appreciated by those skilled in the art that any block diagrams herein represent conceptual views of illustrative systems embodying the principles of the present subject matter. Similarly, it will be appreciated that any flow charts, flow diagrams, state transition diagrams, pseudo code, and the like represent various processes which may be substantially represented in computer-readable medium and executed by a computer or processor, whether or not such computer or processor is explicitly shown.

[0031] In the present document, the word "exemplary" is used herein to mean "serving as an example, instance, or illustration". Any embodiment or implementation of the present subject matter described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

[0032] While the disclosure is susceptible to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the drawings and will be described in detail below. It should be understood, however that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the spirit and the scope of the disclosure.

[0033] The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a setup, device, or method that comprises a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such setup or device or method. In other words, one or more elements in a device or system or apparatus proceeded by "comprises쪋 a" does not, without more constraints, preclude the existence of other elements or additional elements in the device or system or apparatus.

[0034] FIG. 1 illustrates a data flow representation 100 of a conventional implicit sounding, in accordance with the conventional technology.

[0035] As shown in FIG. 1, in implicit sounding, an Access Point AP 101 sends a trigger frame to trigger single / multiple Stations (STAs) such as a (STA) 103, to send a Null Data Packet (NDP) in uplink channel. After receiving the NDP from the STA 103, the AP 101 calculates the beamforming weights. The beam forming weights is calculated based on summing the trigger frame from the AP 103 and the NDP in uplink channel from the STA 103, as represented in below equation (1):

[0036] Beam forming weights = Trigger frame from the AP 101 + NDP in uplink channel from the STA 103 ----------(1)

[0037] FIG. 2 illustrates a data flow representation 200 of a conventional explicit sounding, in accordance with the conventional technology.

[0038] As shown in FIG. 2, in explicit channel sounding, the AP 101 sends a channel sounding announcement such as a Null Data Packet Announcement (NDPA) followed by transmission of NDP frame to the STA 103. Further, the STA 103 sends CSI report feedback to the AP 101.

[0039] However, in Wi-Fi 8, considering MAP coordination still remains unresolved. Coordinated beamforming (Co-BF) is one such MAP feature which requires a sounding between APs and STAs of multiple Basic Service Set (BSS) involved in coordination. Most of the technical proposals for sounding for coordinated beamforming are divided in two categories such as a sequential sounding, and a joint Sounding.

[0040] In sequential sounding, each of the APs comprising at least the AP 101 transmits the NDP independently in a sequential manner without any overlap between sounding period. In joint sounding, the all the APs comprising at least the AP 101 transmit NDP simultaneously, each transmitting on different spatial streams and dimensions.

[0041] Further, explicit coordinated sounding is done in two ways such as explicit co-ordinated sequential sounding and explicit co-ordinated joint sounding. In explicit co-ordinated sequential sounding, each of the APs comprising at least the AP 101 performs the channel sounding separately. Each of the APs transmit sounding NDP individually and only one at a time. The STAs comprising at least the STA 103 also sends feedback separately to each of the APs.

[0042] In explicit coordinated joint sounding, all coordinating APs comprising at least the AP 101 jointly transmits sounding NDP and all the transmissions are performed simultaneously. All the STAs comprising at least the STA 103 sends feedback jointly to all the coordinating APs, in which the feedback includes CSI.

[0043] In implicit coordinated sounding, all the APs performing sounding calculate the CSI based on the NDP frame sent by the STAs. This sounding process assumes that the impulse response of the uplink channel and downlink channel is identical in a coherence interval. However, in the existing technologies, sharing information about APs and STAs involved in sounding needs, between APs and STAs which are to be sounded are currently missing. Further, there is a need for a method for such information exchange. Furthermore, there is a lack of signalling from one AP to another AP to initiate sounding. In addition, there is a need for a method to enable such a coordinated effort of sounding.

[0044] In the following detailed description of the embodiments of the disclosure, reference is made to the accompanying drawings that form a part hereof, and in which are shown by way of illustration specific embodiments in which the disclosure may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosure, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the present disclosure. The following description is, therefore, not to be taken in a limiting sense.

[0045] Embodiments described herein provide a method and an Access Point (AP) for enabling a coordinated operation in a Multi-Access Point (MAP) communication network.

[0046] In an embodiment, the method comprises broadcasting, by at least one Access Point (AP) from a plurality of Access Points (APs) present in a Multi-Access Point (MAP) communication network, a Null Data Packet Announcement (NDPA), in which the NDPA comprises one or more primary information elements, corresponding to a sounding operation. In an embodiment, the NDPA is available to the plurality of APs, and a station. The method then includes transmitting, by the at least one AP, a Null Data Packet (NDP) to the station, to enable the station to determine a Channel State Information (CSI), based on the transmitted NDP. Further, the method includes broadcasting, by the at least one AP, a sounding report request, based on the transmitted NDP, in which the sounding report request comprises one or more secondary information elements corresponding to the sounding operation. In an embodiment, the sounding report request is available to the plurality of APs, and the station. Further, in an embodiment, the station is configured to transmit a sounding report to the at least one AP, based on the sounding report request. Furthermore, the method comprises determining, by the at least one AP, one or more signal transmission actions for performing a coordinated operation, based on the sounding report. In an embodiment, the sounding report is shared between the plurality of APs.

[0047] In an embodiment, the AP comprises a processor and a memory coupled with the processor. The processor is configured to broadcast a Null Data Packet Announcement (NDPA), in which the NDPA comprises one or more primary information elements, corresponding to a sounding operation. In an embodiment, the NDPA is available to a plurality of APs, and a station. The processor is further configured to transmit a Null Data Packet (NDP) to the station, to enable the station to determine a Channel State Information (CSI), based on the transmitted NDP. Further, the processor is configured to broadcast a sounding report request, based on the transmitted NDP, in which the sounding report request comprises one or more secondary information elements corresponding to the sounding operation. In an embodiment, the sounding report request is available to the plurality of APs, and the station. Further, in an embodiment, the station is configured to transmit a sounding report to the at least one AP, based on the sounding report request. Furthermore, the processor is configured to determine one or more signal transmission actions for performing a coordinated operation, based on the sounding report. In an embodiment, the sounding report is shared between the plurality of APs.

[0048] Another aspect of the present disclosure provides a method and a station for enabling a coordinated operation in a Multi-Access Point (MAP) communication network.

[0049] In an embodiment, the method comprises receiving, by a station, a Null Data Packet Announcement (NDPA) broadcasted by the at least one Access Point (AP) from a plurality of APs present in a Multi-Access Point (MAP) communication network, in which the NDPA comprises one or more primary information elements (IEs) corresponding to a sounding operation. In an embodiment, the NDPA is available to the plurality of APs, and the station. The method then includes receiving, by the station, a Null Data Packet (NDP) from the at least one AP to determine a Channel State Information (CSI). Further, the method includes receiving, by the station, a sounding report request broadcasted by the at least one AP, based on the received NDP, in which the sounding report request comprises one or more secondary information elements corresponding to the sounding operation. In an embodiment, the sounding report request is available to the plurality of APs, and the station. Furthermore, the method includes generating, by the station, a sounding report, based on the sounding report request and transmitting the sounding report to the at least one AP for enabling the coordinated operation in the MAP communication network.

[0050] In an embodiment, the station comprises a processor and a memory coupled with the processor. The processor is configured to receive a Null Data Packet Announcement (NDPA) broadcasted by at least one Access Point (AP) from a plurality of Access Points (APs) present in a Multi-Access Point (MAP) communication network, in which the NDPA comprises one or more primary information elements corresponding to a sounding operation. In an embodiment, the NDPA is available to the plurality of APs, and a station. The processor is further configured to receive a Null Data Packet (NDP) from the at least one AP to determine a Channel State Information (CSI). Further, the processor is configured to receive a sounding report request broadcasted by the at least one AP, based on the received NDP, in which the sounding report request comprises one or more secondary information elements corresponding to the sounding operation. In an embodiment, the sounding report request is available to the plurality of APs, and the station. Furthermore, the processor is configured to generate a sounding report, based on the sounding report request and transmitting the sounding report to the at least one AP for enabling the coordinated operation in the MAP communication network.

[0051] The present disclosure generally relates to the field of wireless communication systems. More particularly, the present disclosure relates to a method and a system for enabling sounding operation for Co-ordinated Beamforming in Multi-AP WLAN Network.

[0052] Wireless local area networks (WLANs) have evolved continuously during the past two decades in order to offer high data rates at lower costs. Beamforming is a technology thatenhances signal strength and lowers interference by directing wireless signals towards particular devices. Coordination of beamforming helps improve wireless communication in a multi-AP WLAN network by enabling cooperation between numerous access points (APs).

[0053] Sounding operation for beamforming was first introduced in IEEE 802.11n (Wi-Fi 4).Wi-Fi 4 has introduced multiple input multiple output (MIMO) to transmit multiple data streams simultaneously. To make MIMO more efficient, sounding was required to estimate the quality of the wireless channel i.e. channel state information (CSI) to optimize transmission. Sounding becomes more important in the latter versions of Wi-Fi i.e. Wi-Fi 5 (IEEE 802.11ac), Wi-Fi 6 (IEEE 802.11ax) and Wi-Fi 7 (IEEE 802.11be) while considering advanced features like multi user MIMO and beamforming, which requires more precise channel estimates via sounding.

[0054] Reference is made to Figure 1 which illustrates conventional implicit sounding. In implicit sounding, AP sends a trigger frame to trigger single / multiple STAs, to send null data packet (NDP) in uplink. After receiving the NDP from STA, the AP calculates the beamforming weights. (Trigger frame from AP +NDP in uplink from STA).

[0055] Further reference is made to Figure 2 which illustrates conventional explicit sounding. In explicit channel sounding, the AP sends a channel sounding announcement i.e. NDPA followed by the transmission of and NDP frame and finally, the STA sends the CSI report feedback.

[0056] In Wi-Fi 8, considering multi-AP (MAP) coordination still remains unresolved. Coordinated beamforming (Co-BF) is one such MAP feature. Coordinated beamforming requires a sounding between APs and STAs of multiple basic service set (BSS) involved in coordination. Most of the technical proposals for sounding for coordinated beamforming in TGbn are divided in two categories: 1) Sequential sounding 2) Joint Sounding.

[0057] In sequential sounding, each AP transmits NDP independently in a sequential manner (only one at a time, similar to single AP sounding) without any overlap between sounding period. (reference can be made to Fig. 3).

[0058] In joint sounding, the coordinate AP initiates the Joint sounding, APs transmit NDP simultaneously, each transmitting on different spatial streams / dimensions. (reference can be made to Fig. 4)

[0059] Further, explicit coordinated sounding can be done in two ways: a) Explicit co-ordinated sequential sounding and b) Explicit co-ordinated joint sounding.

[0060] In explicit co-ordinated sequential sounding, each AP perform the channel sounding separately. APs transmit sounding NDP individually and only one at a time. STA also send feedback separately (single user feedback report) to each AP.

[0061] In explicit coordinated joint sounding, all coordinating APs jointly transmit sounding NDP and all the transmissions are performed simultaneously. STA send feedback jointly (multi user feedback report) to coordinating APs i.e. global CSI.

[0062] In Implicit coordinated sounding, APs performing sounding calculate CSI based on the NDP frame sent by the STA (received uplink NDP frame). This sounding process assumes that the impulse response of the uplink (UL) and downlink (DL) channel is identical in a coherence interval. Implicit coordinated sounding is divided into two categories a) Implicit coordinated sequential sounding and b) Implicit coordinated joint sounding.

[0063] Therefore, there is a need for sharing information about APs and STAs involved in sounding needs, between APs and STAs which are to be sounded. Further, there is a need for a method for such information exchange. Furthermore, there is a need for signalling from one AP to another AP to initiate sounding. In addition, there is a need for a method to enable such a coordinated effort of sounding.

[0064] The information disclosed in this background of the disclosure section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

[0065] The present disclosure proposes a method and system to enable Sounding operation for Co-ordinated Beamforming in Multi-AP WLAN Network.

[0066] In an embodiment, the present disclosure defines a system and method to enable coordinated beamforming in multi-AP WLAN network which involves coordinated effort for sounding among multiple BSS involved in coordination and sharing of sounding report among multiple APs / BSSs

[0067] In an embodiment, the present disclosure enables coordinated sounding operation among members of MAP network by triggering / scheduling sounding transmissions among multiple Aps and STAs involved.

[0068] In another embodiment, the present disclosure enables coordinated sounding operation among members of MAP network by sharing information about STAs to be sent sounding transmission.

[0069] In an embodiment, present disclosure provides a method to enable report sharing for coordinated sounding operation among members of MAP network by triggering / scheduling sounding report transmission among multiple Aps and STAs involved.

[0070] In an embodiment, present disclosure provides a method to enable report sharing for coordinated sounding operation among members of MAP network by sharing information about STAs / APs to be sent sounding report.

[0071] In an embodiment, a method to enable coordinated sounding operation (for coordinated beamforming) in multi-AP network is defined.

[0072] In an embodiment, a method to trigger / schedule sounding transmission across multiple BSS (among multiple APs and STAs involved in coordination) is defined.

[0073] In an embodiment, a method to trigger / schedule sounding report sharing across multiple BSS (among multiple APs involved in coordination) is defined.

[0074] In an embodiment, a method to share information about STAs of multiple BSS involved in coordinated sounding is defined.

[0075] In an embodiment, information elements (IEs) to be exchanged as part of the messages to trigger / schedule coordinated sounding transmission are defined.

[0076] In an embodiment, IEs to share information about STAs involved in coordinated sounding, sounding report exchange are defined.

[0077] Present disclosure proposes a system and a method that enables coordinated sounding transmission by triggering / scheduling sounding transmissions among multiple APs and STAs involved.

[0078] In an embodiment, in coordinated sounding, NDPA is modified / enhanced to use it as a trigger for scheduling sounding transmission.

[0079] In an embodiment, an identifier and other optional information of sounding AP is newly added to NDPA considering STA identifier which has to be sounded is already included in NDPA from existing knowledge.

[0080] In an embodiment, information about type of coordinated sounding i.e. sounding is of Type A: joint sounding or sounding is of Type B: sequential sounding is added to NDPA.

[0081] In sequential sounding, each AP transmits NDP independently in a sequential manner (only one at a time, similar to single AP sounding) without any overlap between sounding periods. Further, in explicit co-ordinated sequential Sounding, each AP perform the channel sounding separately. APs transmit sounding NDP individually and only one at a time. STA also send feedback separately (single user feedback report) to each AP.

[0082] In explicit coordinated joint sounding, the coordinate AP initiates the Joint sounding by transmitting NDPA, APs transmit NDP simultaneously, each transmitting on different spatial streams / dimensions. Further, in explicit coordinated joint sounding, all coordinating APs jointly transmit sounding NDP and all the transmissions are performed simultaneously. STA send feedback jointly (multi user feedback report) to coordinating APs.

[0083] In an embodiment, in case of explicit co-ordinated sounding, the AP whose identifier is mentioned in NDPA will send out a NDP sounding transmission.

[0084] In an embodiment, the STA whose identifier is included as the part of coordinated sounding NDPA will receive the NDP sounding transmission from the triggered / scheduled AP.

[0085] In another embodiment, in case of implicit co-ordinated sounding the STA whose identifier is included in NDPA will transmit a sounding transmission after being triggered from sounding AP.

[0086] In an embodiment, the sounding AP will receive the sounding transmission for understanding the channel.

[0087] In an embodiment, the present disclosure discloses a method of reporting for co-ordinated sounding transmission.

[0088] In an embodiment, coordinated sounding, beamforming report poll (BFRP) is modified / enhanced to use it as a trigger for scheduling sounding feedback or report.

[0089] In an embodiment, an identifier and other optional information of sounding APs is newly added to BFRP considering STA identifier is polled for report is already included in BFRP from existing knowledge.

[0090] In an embodiment, in case of explicit co-ordinated sounding, the STA whose identifier is included as the part of coordinated sounding BFRP will send the NDP sounding report to all sounding APs.

[0091] In an embodiment, the present disclosure discloses a method for information exchange about STAs for co-ordinated sounding.

[0092] In an embodiment, for co-ordinated sounding, APs need to know identifier and other information of OBSS STAs that need to be sounded.

[0093] In an embodiment, for co-ordinated sounding, STAs need to know identifier and other information of OBSS APs that need to perform sounding operation.

[0094] In an embodiment, the present disclosure discloses a method to use MAP exchange for information exchange about STAs to be involved in sounding among multiple APs.

[0095] In an embodiment, the information about sounding STAs can be shared before every sounding operation.

[0096] In an embodiment, information element (IE) to trigger / schedule co-ordinated sounding transmission is disclosed.

[0097] In an embodiment, IE to trigger / schedule co-ordinated sounding feedback report is disclosed.

[0098] In an embodiment, IE to setup coordinated sounding (Exchanged between APs) is disclosed.

[0099] Therefore, present disclosure helps manage interference and ensures more efficient and reliable wireless communication.

[0100] FIG. 3 illustrates an exemplary environment 300 for enabling a coordinated operation in a Multi-Access Point (MAP) communication network 301, in accordance with some embodiments of the present disclosure.

[0101] In an embodiment, the exemplary environment 300 may comprise a plurality of APs 303 and a station 305. The plurality of APs 303 may further comprise at least one Access Point (AP) 303a. The FIG. 3 illustrates one AP 303a. This must not be considered as a limitation, and a person skilled in the art will appreciate that the more than one AP such as AP 303b, AP 303c, 쪋AP 303n can be part of the plurality of APs 303.

[0102] In an embodiment, the plurality of APs 303 and the station 305 may communicate each other using the MAP communication network 301, in which the MAP communication network 301 may include, for example, but not limited to, a direct interconnection, a Local Area Network (LAN), a Wide Area Network (WAN), a wireless network, a point-to-point network, or another configuration.

[0103] In an embodiment, the plurality of APs 303, and the at least one AP 303a may include, but not limited to, a Wi-Fi router.

[0104] In an embodiment, the station 305 may include, but not limited to, a smartphone, a mobile phone, a personal digital assistant, a tablet computer, a tablet computer, a wearable device, a computer, a laptop computer, an Augmented Reality / Virtual Reality (AR / VR) device, Internet Of Things (IoT) device, a camera, any other device, and the combination thereof.

[0105] The at least one AP 303a may be configured to broadcast a Null Data Packet Announcement (NDPA), in which the NDPA may comprise one or more primary information elements, corresponding to a sounding operation. In an embodiment, the one or more primary information elements may comprise at least one of, for example, but not limited to, an identifier of the plurality of APs 303 for sounding, an identifier of the station 305 to be sounded, a type of sounding, and a spatial stream allocation of the station 305.

[0106] In an embodiment, the NDPA may be available to a plurality of APs 303, and the station 305. The at least one AP 303a may further configured to transmit a Null Data Packet (NDP) to the station 305, to enable the station 305 to determine a Channel State Information (CSI), based on the transmitted NDP. The NDPA is a frame used in channel sounding procedures, to initiate and manage the process of gathering channel state information (CSI) between an Access Point (AP) and one or more stations (STAs).　The NDPA essentially announces that a Null Data Packet (NDP) will be transmitted, which is then used by the receiving device to measure the channel. In an embodiment, at least one AP 303a of the plurality of APs 303 may be configured as a primary AP with the corresponding Dynamic Host configuration Protocol (DHCP) turned on. For example, the primary AP such as the least one AP 303a may take the responsibility of assigning Internet Protocol (IP) addresses to the other APs of the plurality of APs 303. That is, the DHCP of the other APs may be turned off, such that the other APs may rely upon the primary AP for getting respective IP addresses. Further, the primary AP such as the at least one AP 303a may generate the NDPA, based on the assigned IP addresses and may broadcast the NDPA containing the IP addresses, in which the one or more STAs may determine available connections in the MAP communication network 301, based on the broadcasted NDPA. Further, the NDPA may be received by other APs using a control signalling mechanisms such as a wireless backhaul link, such that the other APs may get information of sounding AP present in the NDPA.

[0107] Further, the at least one AP 303a may be configured to broadcast a sounding report request, based on the transmitted NDP, in which the sounding report request BFRP may comprise one or more secondary information elements corresponding to the sounding operation. In an embodiment, the sounding report request is available to the plurality of APs 303, and the station 305. In an embodiment, the one or more secondary information elements (IEs) may comprise at least one of, for example, but not limited to, an identifier of the plurality of APs 303 for sounding, an identifier of the station 305 for report generation, and a spatial stream allocation of the station 305. The sounding report request is a frame used in channel sounding procedures, to initiate and manage the process of gathering sounding report comprising channel state information (CSI) between an Access Point (AP) and one or more stations (STAs).　The sounding report request essentially announces that a sounding report would be generated by one or more STAs and will be shared with the plurality of APs for understanding different channel conditions. In an embodiment, at least one AP 303a of the plurality of APs 303 may be configured as a primary AP with the corresponding Dynamic Host configuration Protocol (DHCP) turned on. For example, the primary AP such as the least one AP 303a may take the responsibility of assigning IP addresses to the one or more STAs which needs to generate sounding report. Further, the primary AP such as the at least one AP 303a may generate the sounding report request, based on the assigned IP addresses and may broadcast the sounding report request containing the IP addresses, in which the one or more STAs may generate the sounding report, based on the broadcasted sounding report request. Further, the sounding report request may be received by other APs using a control signalling mechanisms such as a wireless backhaul link, such that the other APs may get information of STA which needs to generate sounding report.

[0108] Further, in an embodiment, the station 305 may be configured to transmit a sounding report to the at least one AP 303a, based on the sounding report request (herein also referred as BFRP). Furthermore, the at least one AP 303a may be configured to determine one or more signal transmission actions for performing a coordinated operation, based on the sounding report shared between the plurality of APs 303.

[0109] FIG. 4 illustrates a block diagram of at least one AP 303a, in accordance with some embodiments of the present disclosure.

[0110] As shown in FIG. 4, in an embodiment, the at least one AP 303a may include an I / O interface 403, a processor 405 and a memory 407 storing instructions, executable by the processor 405, which, on execution, may cause the at least one AP 303a to enable a coordinated operation in the MAP communication network 301. In an embodiment, the memory 407 may include data 409 and one or more modules 411. In an embodiment, each of the one or more modules 411 may be a hardware unit which may be outside the memory 407 and coupled with the at least one AP 303a.

[0111] In an embodiment, the data 409 may include for example, a NDPA 413, a NDP 415, a sounding report request 417 and the sounding report 419. In an embodiment, the NDPA 413 may comprise one or more primary information elements, corresponding to a sounding operation. Further, in an embodiment, the one or more primary information elements may comprise at least one of, for example, but not limited to, an identifier of the plurality of APs 303 for sounding, an identifier of the station 305 to be sounded, a type of sounding, and a spatial stream allocation of the station 305.

[0112] Further in an embodiment, the one or more modules 411 may include a NDPA broadcasting module 421, a NDP transmitting module 423, a sounding report request broadcasting module 425, and an action determination module 427.

[0113] In an embodiment, the NDPA broadcasting module 421 may be configured to broadcast a NDPA 413, in which the NDPA 413 may comprise one or more primary information elements, corresponding to a sounding operation. In an embodiment, the NDPA 413 may be available to the plurality of APs 303, and the station 305. Further, in an embodiment, the one or more primary information elements may comprise at least one of, for example, but not limited to, an identifier of the plurality of APs 303 for sounding, an identifier of the station 305 to be sounded, a type of sounding, and a spatial stream allocation of the station 305. Further, in an embodiment, the one or more primary information elements may be incorporated into a header field of the NDPA 413 frame format.

[0114] In an embodiment, the one or more primary information elements may be represented as shown in Table 1:

[0115] [Table 1]

[0116]

[0117] In an embodiment, the NDPA broadcasting module 421 may identify a connection associated between the station 305 and the plurality of APs 303 in the MAP communication network 301. In an embodiment, at least one AP 303a of the plurality of APs 303 may be configured as a primary AP with the corresponding Dynamic Host configuration Protocol (DHCP) turned on. For example, the primary AP such as the least one AP 303a may take the responsibility of assigning IP addresses to the other APs of the plurality of APs 303. That is, the DHCP of the other APs may be turned off, such that the other APs may rely upon the primary AP for getting respective IP addresses. Further, the primary AP such as the at least one AP 303a may generate the NDPA, based on the assigned IP addresses and may broadcast the NDPA comprising the IP addresses, in which the one or more STAs may determine available connections in the MAP communication network 301, based on the broadcasted NDPA. Further, the NDPA 413 may be received by other APs using a control signalling mechanisms such as a wireless backhaul link, such that the other APs may get information of sounding AP present in the NDPA 413.

[0118] Further, the NDPA broadcasting module 421 may determine an AP from the plurality of APs 303 to perform sounding operation, based on the identified connection, and generate the NDPA 413, based on the determined AP for performing the sounding operation. Further, the NDPA broadcasting module 421 may broadcast the generated NDPA 413.

[0119] In an embodiment, the NDP transmitting module 423 may be configured to transmit the NDP 415 to the station 305, to enable the station 305 to determine a Channel State Information (CSI), based on the transmitted NDP 415. In an embodiment, the NDP transmitting module 423 may identify an identifier of a sounding AP, present in the NDPA 413, and transmit the NDP 415 to the station 305, based on the identified identifier. For example, consider a scenario where the AP1 and AP2 may be associated with a STA1. The AP1 may generate a NDPA 413 comprising an ID of AP2 for sounding. Further, based on receiving the broadcasted NDPA 413, the AP2 may identify its own ID present in the NDPA and may activate itself to transmit the NDPA 413 to the STA1.

[0120] In an embodiment, the sounding report request broadcasting module 425 may be configured to broadcast the sounding report request 417, based on the transmitted NDP 415, in which the sounding report request 417 may comprise one or more secondary information elements corresponding to the sounding operation. In an embodiment, the sounding report request 417 may be available to the plurality of APs 303, and the station 305. Further, in an embodiment, the one or more secondary information elements may comprise at least one of, for example, but not limited to, an identifier of the plurality of APs 303 for sounding, an identifier of the station 305 for report generation, and a spatial stream allocation of the station 305. Further, in an embodiment, the one or more secondary information elements may be incorporated into a header field of the BFRP 417 frame format.

[0121] In an embodiment, the one or more secondary information elements (IEs) may be represented as shown in below Table 2:

[0122] [Table 2]

[0123]

[0124] In an embodiment, the sounding report request broadcasting module 425 may determine the station 305 for generating the sounding report 419 and an AP for receiving the sounding report 419, upon transmission of the NDP 415. For example, the sounding report request broadcasting module 425 may include the one or more secondary information elements inside the sounding report request, which clearly indicates the identifier of the particular STA that needs to generate the sounding report 419. Further, the sounding report request broadcasting module 425 may generate the sounding report request 417, based on the determined station 305 and the AP. Furthermore, the sounding report request broadcasting module 425 may broadcast the generated sounding report request 417 to the station 305.

[0125] In an embodiment, the station 305 may be configured to transmit the sounding report 419 to the at least one AP 303a, based on the sounding report request 417. For example, considering a scenario where STA1 may be associated with AP1 and AP2, the STA1 may transmit the sounding report 1 indicating the channel condition between the AP1 and the STA1, to the AP1. Further, the STA1 may transmit the sounding report 2 indicating the channel condition between the AP2 and the STA1, to AP2.

[0126] In an embodiment, the action determination module 427 may be configured to determine one or more signal transmission actions for performing a coordinated operation, based on the sounding report 419 shared between the plurality of APs 303. In an embodiment, the action determination module 427 may exchange the sounding report 419 between the plurality of APs 303 and determine an agreement between the plurality of APs 303, based on the exchanged sounding report 419. In an embodiment, the agreement may correspond to adjusting one or more signal parameters. Further, the action determination module 427 may determine the one or more signal transmission actions for performing the coordinated operation, based on the determined agreement.

[0127] FIG. 5 illustrates a block diagram of the station 305, in accordance with some embodiments of the present disclosure.

[0128] As shown in FIG. 5, in an embodiment, the station 305 may include an I / O interface 503, a processor 505 and a memory 507 storing instructions, executable by the processor 505, which, on execution, may cause the station 305 to enable a coordinated operation in the MAP communication network 301. In an embodiment, the memory 507 may include data 509 and one or more modules 511. In an embodiment, each of the one or more modules 511 may be a hardware unit which may be outside the memory 507 and coupled with the station 305.

[0129] In an embodiment, the data 509 may include for example, the NDPA 413, the NDP 415, the sounding report request 417, and the sounding report 419.

[0130] Further in an embodiment, the one or more modules 511 may include a NDPA receiving module 513, a NDP receiving module 515, a sounding report request receiving module 517, and a sounding report generation module 519.

[0131] In an embodiment, the NDPA receiving module 513 may be configured to receive the NDPA 413 broadcasted by the at least one AP 303a from the plurality of APs 303 present in the MAP communication network 301, in which the NDPA 413 may comprise one or more primary information elements corresponding to a sounding operation. In an embodiment, the NDPA 413 may be available to the plurality of APs 303, and the station 305. Further, in an embodiment, the one or more primary information elements (IEs) may comprise at least one of, for example, but not limited to, an identifier of the plurality of APs 303 for sounding, an identifier of the station 305 to be sounded, a type of sounding, and a spatial stream allocation of the station 305.

[0132] In an embodiment, the NDP receiving module 515 may be configured to receive the NDP 415 from the at least one AP 303a to determine the Channel State Information (CSI). In an embodiment, the NDP receiving module 515 may identify an identifier of a sounding AP, present in the broadcasted NDPA 413, and receive the NDP 415 from the sounding AP, based on the identification.

[0133] In an embodiment, the sounding report request receiving module 517 may be configured to receive the sounding report request 417 broadcasted by the at least one AP 303a, based on the received NDP 415, in which the sounding report request 417 may comprise one or more secondary information elements (IEs) corresponding to the sounding operation. In an embodiment, the sounding report request 417 may be available to the plurality of APs 303, and the station 305. Further, in an embodiment, the one or more secondary IEs may comprise at least one of, for example, but not limited to, an identifier of the plurality of APs 303 for sounding, an identifier of the station 305 for report generation, and a spatial stream allocation of the station 305.

[0134] In an embodiment, the sounding report generation module 519 may be configured to generate the sounding report 419, based on the sounding report request 417 and transmit the sounding report 419 to the at least one AP 303a for enabling the coordinated operation in the MAP communication network 301. In an embodiment, the sounding report generation module 519 may identify an identifier of the station 305 for generating the sounding report 419 and the at least one AP 303a for receiving the sounding report 419, from the broadcasted sounding report request 417, and transmit the generated sounding report 419 to the at least one AP 303a, based on the identifier.

[0135] FIGs. 6a-6b illustrates a scenario representation of enabling a coordinated operation in a Multi-Access Point (MAP) communication network 301 when the type of sounding corresponds to a sequential sounding, in accordance with some embodiments of the present disclosure.

[0136] In an embodiment, as shown in FIGs. 6a and 6b, the at least one AP 303a may transmit the NDP 415 to the station 305 sequentially and receive the sounding report 419 sequentially from the station 305. More specifically, the at least one AP 303a such as, for example, but not limited to, AP1 (also referred as AP1 303a) and at least one AP 303b such as AP2 (also referred as AP2 303b) (as shown in FIG. 6) of the plurality of APs 303 may transmit the NDP 415 independently in a sequential manner without any overlap between sounding periods. Further, the AP1 303a and the AP2 303b may perform the channel sounding separately. In other words, each of the AP of the plurality of APs 303 may transmit sounding NDP 415 individually and only one at a time. Further, the station 305 (hereafter also referred as STA 305) such as for example, but not limited to STA1 405a and STA2 405b may also send feedback separately to the respective AP of the plurality of APs 303. In an embodiment, the feedback may correspond to at least the sounding report 419. For example, considering a scenario where STA1 405a may be associated with AP1 303a and AP2 303b, the STA1 405a may transmit the sounding report 1 indicating the channel condition between the AP1 303a and the STA1 405a, to the AP1 303a. Further, the STA1 405a may transmit the sounding report 2 indicating the channel condition between the AP2 303b and the STA1 405a, to the AP2 303b.

[0137] For example, the steps of enabling the coordinated operation in the MAP communication network 301 when the type of sounding corresponds to a sequential sounding comprises one or more following cases.

[0138] Case 1:When the identifier of plurality of APs 303 present in the NDPA 413 is the identifier of the AP1 303a, the identifier of the station 305 to be sounded is identifier of STA1 405a, the type of sounding is sequential sounding, as shown in FIG. 6A.

[0139] Step 1:AP1 303a may broadcast the NDPA 413 which may be available to the AP2 303b, STA1 405a, and STA2 405b.

[0140] Step 2:AP1 303a may transmit the NDP 415 to the STA1 405a.

[0141] Step 3: AP1 303a may broadcast the sounding report request 417 (also hereafter referred as Beamforming Report Poll (BFRP) 417) which may be available to the AP2 303b, STA1 405a, and STA2 405b, in which the one or more secondary information elements (IEs) may comprise the identifier of the plurality of APs 303 for sounding as identifier of AP1 303a, the identifier of the station 305 for report generation as identifier of STA1 405a, and a spatial stream allocation of the STA1 405a.

[0142] Step 4: STA1 405a may transmit the sounding report 419 (also referred as Beamforming Report (BFR) 419) to the AP1 303a.

[0143] Step 5: AP1 303a may share the sounding report with the AP2 303b to enable the coordinated operation in the MAP communication network 301.

[0144] Case 2:When the identifier of plurality of APs 303 present in the NDPA 413 is the identifier of the AP2 303b, the identifier of the station 305 to be sounded is identifier of STA1 405a, the type of sounding is sequential sounding, as shown in FIG. 6A.

[0145] Step 1: AP1 303a may broadcast the NDPA 413 which may be available to the AP2 303b, STA1 405a, and STA2 405b.

[0146] Step 2:AP2 303b may transmit the NDP 415 to the STA 1 405a.

[0147] Step 3: AP1 303a may broadcast the sounding report request 417 which may be available to the AP2 303b, STA1 405a, and STA2 405b, in which the one or more secondary information elements (IEs) may comprise the identifier of the plurality of APs 303 for sounding as identifier of AP2 303b, the identifier of the station 305 for report generation as identifier of STA1 405a, and a spatial stream allocation of the STA1 405a.

[0148] Step 4:STA1 405a may transmit the sounding report 419 to the AP2 303b.

[0149] Step 5: AP2 303b may share the sounding report with the AP1 303a to enable the coordinated operation in the MAP communication network 301.

[0150] Case 3:When the identifier of plurality of APs 303 present in the NDPA 413 is the identifier of the AP1 303a, the identifier of the station 305 to be sounded is identifier of STA2 405b, the type of sounding is sequential sounding, as shown in FIG. 6B.

[0151] Step 1:AP2 303b may broadcast the NDPA 413 which may be available to the AP1 303a, STA1 405a, and STA2 405b.

[0152] Step 2:AP1 303a may transmit the NDP 415 to the STA2 405b.

[0153] Step 3: AP2 303b may broadcast the sounding report request 417 which may be available to the AP1 303a, STA1 405a, and STA2 405b, in which the one or more secondary information elements may comprise the identifier of the plurality of APs 303 for sounding as identifier of AP1 303a, the identifier of the station 305 for report generation as identifier of STA2 405b, and a spatial stream allocation of the STA2 405b.

[0154] Step 4: STA2 405b may transmit the sounding report 419 to the AP1 303a.

[0155] Step 5: AP1 303a may share the sounding report with the AP2 303b to enable the coordinated operation in the MAP communication network 301.

[0156] Case 4:When the identifier of plurality of APs 303 present in the NDPA 413 is the identifier of the AP2 303b, the identifier of the station 305 to be sounded is identifier of STA2 405b, the type of sounding is sequential sounding, as shown in FIG. 6B.

[0157] Step 1: AP2 303b may broadcast the NDPA 413 which may be available to the AP1 303a, STA1 405a, and STA2 405b.

[0158] Step 2:AP2 303b may transmit the NDP 415 to the STA2 405b.

[0159] Step 3: AP2 303b may broadcast the sounding report request 417 which may be available to the AP1 303a, STA1 405a, and STA2 405b, in which the one or more secondary information elements may comprise the identifier of the plurality of APs 303 for sounding as identifier of AP2 303b, the identifier of the station 305 for report generation as identifier of STA2 405b, and a spatial stream allocation of the STA2 405b.

[0160] Step 4: STA2 405b may transmit the sounding report 419 to the AP2 303b.

[0161] Step 5: AP2 303b may share the sounding report with the AP1 303a to enable the coordinated operation in the MAP communication network 301.

[0162] FIG. 7 illustrates a scenario representation of enabling a coordinated operation in a Multi-Access Point (MAP) communication network 301 when the type of sounding corresponds to a joint sounding, in accordance with some embodiments of the present disclosure.

[0163] In an embodiment, the at least one AP 303a may transmit the NDP 415 to the station 305 simultaneously and receive the sounding report 419 simultaneously from the station 305. More specifically, the AP1 303a and AP2 303b may initiate the joint sounding by transmitting the NDPA 413, and the plurality of APs 303 may transmit the NDP 415 simultaneously, each transmitting on different spatial streams and dimensions. Further the STA 305 such as for example, but not limited to, STA1 405a and STA2 405b may send feedback jointly to the at least one AP 303a.

[0164] For example, the steps of enabling the coordinated operation in the MAP communication network 301 when the type of sounding corresponds to a joint sounding comprises one or more following cases:

[0165] Case 1:When the identifier of plurality of APs 303 present in the NDPA 413 is the identifier of the AP1 303a and AP2 303b, the identifier of the station 305 to be sounded is identifier of STA1 405a, the type of sounding is joint sounding.

[0166] Step 1: AP1 303a may broadcast the NDPA 413 which may be available to the AP2 303b, STA1 405a, and STA2 405b.

[0167] Step 2:AP1 303a and AP2 303b may transmit the NDP 415 to the STA1 405a.

[0168] Step 3: AP1 303a may broadcast the sounding report request 417 which may be available to the AP2 303b, STA1 405a, and STA2 405b, in which the one or more secondary information elements may comprise the identifier of the plurality of APs 303 for sounding as identifier of AP1 303a and AP2 303b, the identifier of the station 305 for report generation as identifier of STA1 405a, and a spatial stream allocation of the STA1 405a.

[0169] Step 4: STA1 405a may transmit the sounding report 419 independently to the AP1 303a and AP2 303b.

[0170] Step 5:AP1 303a may share the sounding report with the AP2 303b, and AP2 303b may share the sounding report with AP1 303a, to enable the coordinated operation in the MAP communication network 301.

[0171] Case 2:When the identifier of plurality of APs 303 present in the NDPA 413 is the identifier of the AP1 303a and AP2 303b, the identifier of the station 305 to be sounded is identifier of STA2 405b, the type of sounding is joint sounding.

[0172] Step 1:AP2 303b may broadcast the NDPA 413 which may be available to the AP1 303a, STA1 405a, and STA2 405b.

[0173] Step 2:AP1 303a and AP2 303b may transmit the NDP 415 to the STA2 405b.

[0174] Step 3:AP2 303b may broadcast the sounding report request (BFRP) 417 which may be available to the AP1 303a, STA1 405a, and STA2 405b, in which the one or more secondary information elements (IES) may comprise the identifier of the plurality of APs 303 for sounding as identifier of AP1 303a and AP2 303b, the identifier of the station 305 for report generation as identifier of STA2 405b, and a spatial stream allocation of the STA2 405b.

[0175] Step 4: STA2 405b may transmit the sounding report 419 independently to the AP1 303a and AP2 303b.

[0176] Step 5: AP1 303a may share the sounding report with the AP2 303b, and AP2 303b may share the sounding report with AP1 303a, to enable the coordinated operation in the MAP communication network 301.

[0177] FIG. 8 illustrates a scenario representation of sharing the sounding report for enabling a coordinated operation in a Multi-Access Point (MAP) communication network 301, in accordance with some embodiments of the present disclosure.

[0178] In an embodiment, the at least one AP 303a such as the AP1 303a and AP2 303b may exchange the sounding report 419 between the plurality of APs 303. Further, the at least one AP 303a may determine an agreement between the plurality of APs 303, based on the exchanged sounding report 419, in which the agreement may correspond to adjusting one or more signal parameters. Further, the at least one AP 303a may determine the one or more signal transmission actions for performing the coordinated operation, based on the determined agreement.

[0179] For example, as shown in FIG. 8, the AP1 303a may receive the BFR 419 such as BFR1 from the STA1 405a. Further, the AP2 303b may receive the BFR 419 such as BFR2 from the STA2 405b. Further, the AP1 303a may share the BFR1 with the AP2 303b, and the AP2 303b may share the BFR2 with the AP1 303a. Based on the exchange of the BFR 419, the AP1 303a may determine an agreement with the AP2 303b, in which the agreement may correspond to adjusting one or more signal parameters. In an embodiment, the one or more signal parameters may comprise, for example, but not limited to, a phase of signal, and magnitude of signal. Further, the AP1 303a may determine the one or more signal transmission actions for performing the coordinated operation, based on the determined agreement. In an embodiment, the one or more signal transmission actions may comprise, for example, but not limited to, beamforming actions, and nulling actions corresponding to interference cancellation. In other words, MAP Coordination (MAPC) negotiation procedure may be used for establishment of agreement between the AP1 303a and AP2 303b. For example, to support MAPC transmissions, the one or more APs such as the AP2 303b may share information with a central controller such as the primary AP such as the AP1 303a. The primary AP may be responsible for computing and periodically informing transmission parameters, as well as the most suitable subset of transmitting APs for every Transmission Opportunity (TXOP). That is, the one or more APs and the primary AP may exchange most of the information through a low-latency and high bandwidth wired backbone.

[0180] In an embodiment, the MAPC negotiation procedure may allow the one or more APs to share a TXOP opportunity, in which the MAPC transmissions may be scheduled periodically every T ms with uncoordinated (CSMA / CA) transmissions in between. A MAPC transmission may be initiated when the sharing AP such as the AP2 303b accesses the channel and sends a MAP request-to-send (MAP-RTS) frame for channel reservation. If no collision occurs, the Shared AP such as the AP1 303a reply at the same time with a MAP clear-to-send (MAP-CTS) frame. The latter may be also useful to inform stations or legacy devices about the ongoing MAPC transmission, thus avoiding unwanted collisions with hidden devices. At this point, the Sharing AP assumes that all neighbouring devices have properly set their network allocation vector (NAV), and so the MAPC transmission may not be disturbed until it ends. Once the Sharing AP accesses the channel, the gained TXOP may be splitted in one or more temporal slots (also referred as coordinated slots). One or more APs may be allocated in each coordinated slot.

[0181] In an embodiment, the MAPC scheduling may be split into two main stages: the First Stage includes the creation of the SR-Compatible groups based on the signal-to-interference-plus-noise ratio (SINR) between all AP and station pairs, and the second Stage, employing the built groups to select the APs that are scheduled in every MAPC transmission. The First Stage provides a procedure to verify the compatibility of a group of APs to transmit simultaneously. The groups of compatible APs are created based on the Signal-to-Interference Noise Ratio (SINR) at associated stations. The Second Stage is intended for scheduling one compatible group (from the ones previously computed in the First Stage) per coordinated slot based on the buffer state information collected from all APs, which contains the number of packets in the transmission buffer of each AP, as well as the arrival time of the oldest packet.

[0182] FIG. 9 illustrates a scenario representation of performing the coordinated operation, based on determined agreement between at least one AP 303a and the plurality of APs 303, in accordance with some embodiments of the present disclosure.

[0183] In an embodiment, for example, based on the exchange of the BFR 419, as shown in FIG. 8, the AP1 303a may determine an agreement with the AP2 303b, in which the agreement may correspond to adjusting one or more signal parameters. In an embodiment, the one or more signal parameters may comprise, for example, but not limited to, a phase of signal, and magnitude of signal. Further, the AP1 303a may determine the one or more signal transmission actions for performing the coordinated operation, based on the determined agreement. In an embodiment, the one or more signal transmission actions may comprise, for example, but not limited to, beamforming actions, and nulling actions corresponding to interference cancellation.

[0184] For example, as shown in FIG. 9, the AP1 303a and AP2 303b may comprise a plurality of transmit antennas, and the STA1 405a and the STA2 405b may comprise a plurality of receiver antennas.

[0185] In an embodiment, based on the report shared by the AP2 303b, the AP1 303a may determine the channel matrix H and may the Moore-Penrose inverse (or pseudo-inverse) of　H, denoted as　HH / ||HHH||. Further, the AP1 303a may design the precoding matrix　as represented in below equation (2)

[0186] P　=　HH / ||HHH|| -----------------(2)

[0187] whereHrepresents a Hermitian operator

[0188] Further, the AP1 303a may multiply the transmission signal with the precoded matrix P to obtain the precoded signal　Px. For example, the AP1 303a may use first set of plurality of transmit antennas for reducing power of transmission of signals, and adjusting phase and magnitude of the signals to STA1 405a and may use second set of plurality of transmit antennas for nulling interference at the STA2 405b. Without limiting to AP1 303a, the similar procedure may be carried out by AP2 303b for nulling interference at the STA1 405a.

[0189] FIG. 10 illustrates a flowchart representation of a method 1000 of enabling a coordinated operation in a Multi-Access Point (MAP) communication network 301 by at least one AP 303a, in accordance with some embodiments of the present disclosure.

[0190] At step 1001, the method 1000 includes broadcasting, by the least one AP 303a from a plurality of APs 303 present in a MAP communication network 301, a NDPA 413. In an embodiment, the NDPA broadcasting module 421 may be configured to broadcast a NDPA 413, in which the NDPA 413 may comprise one or more primary information elements, corresponding to a sounding operation. In an embodiment, the NDPA 413 may be available to the plurality of APs 303, and the station 305. Further, in an embodiment, the one or more primary information elements may comprise at least one of, for example, but not limited to, an identifier of the plurality of APs 303 for sounding, an identifier of the station 305 to be sounded, a type of sounding, and a spatial stream allocation of the station 305.

[0191] In an embodiment, the NDPA broadcasting module 421 may identify a connection associated between the station 305 and the plurality of APs 303 in the MAP communication network 301. Further, the NDPA broadcasting module 421 may determine an AP from the plurality of APs 303 to perform sounding operation, based on the identified connection, and generate the NDPA 413, based on the determined AP for performing the sounding operation. Further, the NDPA broadcasting module 421 may broadcast the generated NDPA 413.

[0192] At step 1002, the method 1000 includes transmitting, by the at least one AP 303a, the NDP 415 to the station 305, to enable the station to determine a Channel State Information (CSI), based on the transmitted NDP 415. In an embodiment, the NDP transmitting module 423 may be configured to transmit the NDP 415 to the station 305, to enable the station 305 to determine a Channel State Information (CSI), based on the transmitted NDP 415. In an embodiment, the NDP transmitting module 423 may identify an identifier of a sounding AP, present in the NDPA 413, and transmit the NDP 415 to the station 305, based on the identified identifier.

[0193] At step 1003, the method 1000 includes broadcasting, by the at least one AP 303a, the sounding report request 417, based on the transmitted NDP 415. In an embodiment, the sounding report request broadcasting module 425 may be configured to broadcast the sounding report request 417, based on the transmitted NDP 415, in which the sounding report request 417 may comprise one or more secondary information elements corresponding to the sounding operation. In an embodiment, the sounding report request 417 may be available to the plurality of APs 303, and the station 305. Further, in an embodiment, the one or more secondary information elements (IEs) may comprise at least one of, for example, but not limited to, an identifier of the plurality of APs 303 for sounding, an identifier of the station 305 for report generation, and a spatial stream allocation of the station 305.

[0194] At step 1004, the method 1000 includes determining, by the at least one AP 303a, one or more signal transmission actions for performing a coordinated operation, based on the sounding report 419, in which the sounding report 419 may be shared between the plurality of APs 303. In an embodiment, the action determination module 427 may be configured to determine one or more signal transmission actions for performing a coordinated operation, based on the sounding report 419 shared between the plurality of APs 303. In an embodiment, the action determination module 427 may exchange the sounding report 419 between the plurality of APs 303 and determine an agreement between the plurality of APs 303, based on the exchanged sounding report 419. In an embodiment, the agreement may correspond to adjusting one or more signal parameters. Further, the action determination module 427 may determine the one or more signal transmission actions for performing the coordinated operation, based on the determined agreement.

[0195] FIG. 11 illustrates a flowchart representation of a method of enabling a coordinated operation in a Multi-Access Point (MAP) communication network 301 by a station 305, in accordance with some embodiments of the present disclosure.

[0196] At step 1101, the method 1100 includes receiving, by the station 305, a Null Data Packet Announcement (NDPA) 413 broadcasted by the at least one Access Point (AP) 303a from a plurality of Access Points (APs) 303 present in a Multi-Access Point (MAP) communication network 301. In an embodiment, the NDPA receiving module 513 may be configured to receive the NDPA 413 broadcasted by the at least one AP 303a from the plurality of APs 303 present in the MAP communication network 301, in which the NDPA 413 may comprise one or more primary information elements (IEs) corresponding to a sounding operation. In an embodiment, the NDPA 413 may be available to the plurality of APs 303, and the station 305. Further, in an embodiment, the one or more primary t IEs may comprise at least one of, for example, but not limited to, an identifier of the plurality of APs 303 for sounding, an identifier of the station 305 to be sounded, a type of sounding, and a spatial stream allocation of the station 305.

[0197] At step 1102, the method 1100 includes receiving, by the station 305, a Null Data Packet (NDP) 415 from the at least one AP 303a to determine a Channel State Information (CSI). In an embodiment, the NDP receiving module 515 may be configured to receive the NDP 415 from the at least one AP 303a to determine the CSI. In an embodiment, the NDP receiving module 515 may identify an identifier of a sounding AP, present in the broadcasted NDPA 413, and receive the NDP 415 from the sounding AP, based on the identification.

[0198] At step 1103, the method 1100 includes receiving, by the station 305, a sounding report request 417 broadcasted by the at least one AP 303a, based on the received NDP 415. In an embodiment, the sounding report request receiving module 517 may be configured to receive the sounding report request 417 broadcasted by the at least one AP 303a, based on the received NDP 415, in which the sounding report request 417 may comprise one or more secondary information elements (IEs) corresponding to the sounding operation. In an embodiment, the sounding report request 417 may be available to the plurality of APs 303, and the station 305. Further, in an embodiment, the one or more secondary IEs may comprise at least one of, for example, but not limited to, an identifier of the plurality of APs 303 for sounding, an identifier of the station 305 for report generation, and a spatial stream allocation of the station 305.

[0199] At step 1104, the method 1100 includes generating, by the station 305, a sounding report 419, based on the sounding report request 417 and transmitting the sounding report 419 to the at least one AP 303a for enabling the coordinated operation in the MAP communication network 301. In an embodiment, the sounding report generation module 519 may be configured to generate the sounding report 419, based on the sounding report request 417 and transmit the sounding report 419 to the at least one AP 303a for enabling the coordinated operation in the MAP communication network 301. In an embodiment, the sounding report generation module 519 may identify an identifier of the station 305 for generating the sounding report 419 and the at least one AP 303a for receiving the sounding report 419, from the broadcasted sounding report request 417, and transmit the generated sounding report 419 to the at least one AP 303a, based on the identifier.

[0200] The present disclosure proposes a method and system to enable sounding operation for Co-ordinated Beamforming in Multi-AP WLAN Network.

[0201] The present disclosure defines a system and method to enable coordinated beamforming (Co-BF) in multi-AP WLAN network which involves coordinated effort for sounding among multiple BSS involved in coordination and sharing of sounding report among multiple APs / BSSs.

[0202] The present disclosure enables coordinated sounding operation among members of MAP network by triggering / scheduling sounding transmissions among multiple Aps and STAs involved. The present disclosure also enables coordinated sounding operation among members of MAP network by sharing information about STAs to be sent sounding transmission.

[0203] The present disclosure provides a method to enable report sharing for coordinated sounding operation among members of MAP network by triggering / scheduling sounding report transmission among multiple Aps and STAs involved. The present disclosure also provides a method to enable report sharing for coordinated sounding operation among members of MAP network by sharing information about STAs / APs to be sent sounding report.

[0204] The present disclosure provides a method to share information about STAs of multiple BSS involved in coordinated sounding is defined. In the present disclosure, information elements (IEs) to be exchanged as part of the messages to trigger / schedule coordinated sounding transmission are defined.

[0205] In the present disclosure, Information Elements (IEs) to share information about STAs involved in coordinated sounding, sounding report exchange are defined.

[0206] In the present disclosure, the NDPA is modified / enhanced to use it as a trigger for scheduling sounding transmission. Further, in the present disclosure an identifier and other optional information of sounding AP is newly added to NDPA considering STA identifier which has to be sounded is already included in NDPA. The information about type of coordinated sounding such as Type A: joint sounding or sounding and Type B: sequential sounding is added to NDPA.

[0207] In the present disclosure, in case of explicit co-ordinated sounding, the AP whose identifier is mentioned in NDPA will send out a NDP sounding transmission. The STA whose identifier is included as the part of coordinated sounding NDPA will receive the NDP sounding transmission from the triggered / scheduled AP.

[0208] In the present disclosure, in case of implicit co-ordinated sounding the STA whose identifier is included in NDPA will transmit a sounding transmission after being triggered from sounding AP. The sounding AP will receive the sounding transmission for understanding the channel.

[0209] In the present disclosure, a Beamforming Report Poll (BFRP) is modified / enhanced to use it as a trigger for scheduling sounding feedback or report (BFR). The identifier and other optional information of sounding APs is newly added to BFRP considering STA identifier is polled for report is already included in BFRP.

[0210] In the present disclosure, in case of explicit co-ordinated sounding, the STA whose identifier is included as the part of coordinated sounding BFRP will send the NDP sounding report (BFR) to all sounding APs.

[0211] In the present disclosure, for co-ordinated sounding, APs need to know identifier and other information of Overlapping Basic Service Sets (OBSS) STAs that need to be sounded. STAs need to know identifier and other information of OBSS APs that need to perform sounding operation. The present disclosure discloses a method to use MAP exchange for information exchange about STAs to be involved in sounding among multiple APs. The information about sounding STAs is shared before every sounding operation.

[0212] The present disclosure helps manage interference and ensures more efficient and reliable wireless communication.

[0213] The present disclosure facilitates aligning of carrier frequency and improves coordination for beamforming.

[0214] The present disclosure performs better utilization of spectrum, thus increasing spectral efficiency. Further, the present disclosure helps in creating nulls, thus mitigating interference of signals.

[0215] While various aspects and embodiments have been disclosed herein, other aspects and embodiments may be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

Claims

1.A method for enabling a coordinated operation in a multi-access point (MAP) communication network, the method comprising:broadcasting, by at least one access point (AP) from a plurality of APs present in a MAP communication network, a null data packet announcement (NDPA), wherein the NDPA comprises one or more primary information elements, corresponding to a sounding operation, and wherein the NDPA is available to the plurality of APs, and a station;transmitting, by the at least one AP, a null data packet (NDP) to the station;broadcasting, by the at least one AP, a sounding report request, based on the transmitted NDP,wherein the sounding report request comprises one or more secondary information elements corresponding to the sounding operation,wherein the sounding report request is available to the plurality of APs, and the station, andwherein the at least one AP is configured to receive a sounding report from the station, based on the sounding report request; anddetermining, by the at least one AP, one or more signal transmission actions for performing a coordinated operation, based on the sounding report, wherein the sounding report is shared between the plurality of APs.2.The method as claimed in claim 1, wherein broadcasting the NDPA comprises:identifying, by the at least one AP, a connection associated between the station and the plurality of APs in the MAP communication network;determining, by the at least one AP, an AP from the plurality of APs to perform sounding operation, based on the identified connection;generating, by the at least one AP, the NDPA, based on the determined AP for performing the sounding operation; andbroadcasting, by the at least one AP, the generated NDPA.3.The method as claimed in claim 1, wherein transmitting the NDP to the station comprises:identifying, by the at least one AP, an identifier of a sounding AP, present in the NDPA; andtransmitting, by the at least one AP, the NDP to the station to enable the station to determine a channel state information (CSI), based on the identified identifier.4.The method as claimed in claim 1, wherein broadcasting the sounding report request to the station comprises:determining, by the at least one AP, the station for generating the sounding report and an AP for receiving the sounding report, upon transmission of the NDP;generating, by at least one of the AP, the sounding report request, based on the determined station and the AP; andbroadcasting, by the at least one AP, the generated sounding report request to the station.5.The method as claimed in claim 1, wherein if the type of sounding operation corresponds to a sequential sounding operation, the method comprises:transmitting, by the at least one AP, the NDP to the station sequentially; andreceiving, by the at least one AP, the sounding report sequentially from the station.6.The method as claimed in claim 1, wherein if the type of sounding operation corresponds to a joint sounding operation, the method comprises:transmitting, by the at least one AP, the NDP to the station simultaneously; andreceiving, by the at least one AP, the sounding report simultaneously from the station.7.The method as claimed in claim 1, wherein determining the one or more signal transmission actions for performing the coordinated operation comprises:exchanging, by the at least one AP, the sounding report between the plurality of APs;determining, by the at least one AP, an agreement between the plurality of APs, based on the exchanged sounding report, wherein the agreement corresponds to adjusting one or more signal parameters; anddetermining, by the at least one AP, the one or more signal transmission actions for performing the coordinated operation, based on the determined agreement.8.The method as claimed in claim 1, wherein the one or more primary information elements comprises at least one of an identifier of the plurality of APs for sounding, an identifier of the station to be sounded, a type of sounding, and a spatial stream allocation of the station.9.The method as claimed in claim 1, wherein the one or more secondary information elements comprises at least one of an identifier of the plurality of APs for sounding, an identifier of the station for report generation, and a spatial stream allocation of the station.10.An access point (AP) for enabling a coordinated operation in a multi-access point (MAP) communication network, the AP comprising:a processor; anda memory coupled with the processor, wherein the processor is configured to:broadcast a null data packet announcement (NDPA), wherein the NDPA comprises one or more primary information elements, corresponding to a sounding operation, and wherein the NDPA is available to a plurality of APs, and a station;transmit a null data packet (NDP) to the station;broadcast a sounding report request, based on the transmitted NDP,wherein the sounding report request comprises one or more secondary information elements corresponding to the sounding operation,wherein the sounding report request is available to the plurality of APs, and the station, andwherein the at least one AP is configured to receive a sounding report from the station, based on the sounding report request; anddetermine one or more signal transmission actions for performing a coordinated operation, based on the sounding report, wherein the sounding report is shared between the plurality of APs.11.A method for enabling a coordinated operation in a multi-access point (MAP) communication network, the method comprising:receiving, by a station, a null data packet announcement (NDPA) broadcasted by the at least one access point (AP) (303a) from a plurality of access points (APs) present in a multi-access point (MAP) communication network, wherein the NDPA comprises one or more primary information elements corresponding to a sounding operation, and wherein the NDPA is available to the plurality of APs, and the station;receiving, by the station, a null data packet (NDP) from the at least one AP to determine a channel state information (CSI);receiving, by the station, a sounding report request broadcasted by the at least one AP, based on the received NDP, wherein the sounding report request comprises one or more secondary information elements corresponding to the sounding operation, and wherein the sounding report request is available to the plurality of APs, and the station; andgenerating, by the station, a sounding report, based on the sounding report request and transmitting the sounding report to the at least one AP for enabling the coordinated operation in the MAP communication network.12.The method as claimed in claim 11, wherein receiving the NDP from the at least one AP comprises:identifying, by the station, an identifier of a sounding AP, present in the broadcasted NDPA; andreceiving, by the station, the NDP from the sounding AP, based on the identification.13.The method as claimed in claim 11, wherein generating the sounding report, based on the sounding report request comprises:identifying, by the station, an identifier of the station for generating the sounding report and the at least one AP for receiving the sounding report, from the broadcasted sounding report request; andtransmitting, by the station, the generated sounding report to the at least one AP, based on the identifier.14.The method as claimed in claim 11, wherein the one or more primary information elements comprises at least one of an identifier of the plurality of APs for sounding, an identifier of the station to be sounded, a type of sounding, and a spatial stream allocation for the station, andwherein the one or more secondary information elements comprises at least one of an identifier of the plurality of APs for sounding, an identifier of the station for report generation, and a spatial stream allocation for the station.15.A station for enabling a coordinated operation in a multi-access point (MAP) communication network, the station comprising:a processor; anda memory coupled with the processor, wherein the processor is configured to:receive a null data packet announcement (NDPA) broadcasted by at least one access point (AP) from a plurality of APs present in a MAP communication network, wherein the NDPA comprises one or more primary information elements corresponding to a sounding operation, and wherein the NDPA is available to the plurality of APs, and a station;receive a null data packet (NDP) from the at least one AP to determine a channel state information (CSI);receive a sounding report request broadcasted by the at least one AP, based on the received NDP, wherein the sounding report request comprises one or more secondary information elements corresponding to the sounding operation, and wherein the sounding report request is available to the plurality of APs, and the station; andgenerate a sounding report, based on the sounding report request and transmit the sounding report to the at least one AP for enabling the coordinated operation in the MAP communication network.

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