US-12621891-B2 - EMLMR operation for P2P communication

Abstract

Methods and apparatuses for facilitating the use of enhanced multi-link multi-radio (EMLMR) operation for peer-to-peer (P2P) communications between multi-link devices (MLDs). A non-access point (AP) MLD comprises STAs, each comprising a transceiver configured to form a P2P link with a corresponding second STA of a second non-AP MLD, and a processor operably coupled to the first STAs. At least a subset of the P2P links are also EMLMR links configured to operate in an EMLMR mode of operation for P2P communication. The processor is configured to transition the first non-AP MLD into the EMLMR mode of operation for P2P communication over the P2P links. At least one of the first STAs is configured to participate in a P2P EMLMR frame exchange with the corresponding second STA of the second non-AP MLD over at least one of the P2P links.

Inventors

• Rubayet Shafin
• Boon Loong Ng

Assignees

• SAMSUNG ELECTRONICS CO., LTD.

Dates

Publication Date

20260505

Application Date

20230511

Claims (20)

1. 1 . A first non-access point (AP) multi-link device (MLD), comprising: first stations (STAs), each comprising a transceiver configured to form a peer-to-peer (P2P) link with a corresponding second STA of a second non-AP MLD, wherein at least a subset of the P2P links are also enhanced multi-link multi-radio (EMLMR) links configured to operate in an EMLMR mode of operation for P2P communication; and a processor operably coupled to the first STAs, the processor configured to transition the first non-AP MLD into the EMLMR mode of operation for P2P communication over the P2P links, wherein at least one of the first STAs is configured to participate in a P2P EMLMR frame exchange with the corresponding second STA of the second non-AP MLD over at least one of the P2P links; and wherein at least one of the transceivers is further configured to, before the P2P EMLMR frame exchange: transmit, to the second non-AP MLD over the at least one of the P2P links, an EMLMR start frame as an indication that the at least one of the P2P links is selected for the P2P EMLMR frame exchange; or receive, from the second non-AP MLD over the at least one of the P2P links, the EMLMR start frame.
2. 2 . The first non-AP MLD of claim 1 , wherein: the processor is further configured to generate a capability indication message that indicates that the first non-AP MLD supports the EMLMR mode of operation for P2P communication over the P2P links, and at least one of the transceivers is further configured to transmit the capability indication message to the second non-AP MLD.
3. 3 . The first non-AP MLD of claim 2 , wherein: each transceiver is further configured to form a link with a corresponding AP of an AP MLD and at least a subset of the links are also EMLMR links configured to operate in the EMLMR mode of operation for communication with the AP MLD, and the processor is further configured to generate the capability indication message as one of: an EML operating mode notification frame (EOMNF) that includes an indication of the P2P links that are capable of the EMLMR mode of operation for P2P communication; or a basic multi-link element that includes the indication of the P2P links that are capable of the EMLMR mode of operation for P2P communication.
4. 4 . The first non-AP MLD of claim 1 , wherein: at least one of the transceivers is further configured to: transmit, to the second non-AP MLD, an EOMNF that includes an indication to transition into the EMLMR mode of operation for P2P communication and receive, from the second non-AP MLD, an acknowledgement of the EOMNF; or receive, from the second non-AP MLD, the EOMNF and transmit, to the second non-AP MLD, the acknowledgement of the EOMNF, and the processor is further configured to transition the first non-AP MLD into the EMLMR mode of operation for P2P communication over the P2P links after the receipt or the transmission of the acknowledgement.
5. 5 . The first non-AP MLD of claim 1 , wherein: one of the first non-AP MLD or the second non-AP MLD is allowed to initiate transition into the EMLMR mode of operation for P2P communication, at least one of the transceivers is further configured to: based on the first non-AP MLD being allowed to initiate the transition, transmit, to the second non-AP MLD, an EOMNF that includes an indication to transition into the EMLMR mode of operation for P2P communication and receive, from the second non-AP MLD, an acknowledgement of the EOMNF; or based on the second non-AP MLD being allowed to initiate the transition, receive, from the second non-AP MLD, the EOMNF and transmit, to the second non-AP MLD, the acknowledgement of the EOMNF, and the processor is further configured to transition the first non-AP MLD into the EMLMR mode of operation for P2P communication over the P2P links after the receipt or the transmission of the acknowledgement.
6. 6 . The first non-AP MLD of claim 5 , wherein: the one of the first non-AP MLD or the second non-AP MLD that is allowed to initiate the transition is: pre-determined based on relative simultaneous transmit and receive (STR) capabilities of the non-AP MLDs, or determined during a setup procedure for the P2P links that is conducted by the first and second non-AP MLDs.
7. 7 . The first non-AP MLD of claim 1 , wherein: one of the first non-AP MLD or the second non-AP MLD is allowed to select the at least one of the P2P links for the P2P EMLMR frame exchange, and at least one of the transceivers is further configured to, before the P2P EMLMR frame exchange: based on the first non-AP MLD being allowed to select the at least one of the P2P links, transmit, to the second non-AP MLD over the at least one of the P2P links, an EMLMR start frame as an indication that the at least one of the P2P links is selected for the P2P EMLMR frame exchange; or based on the second non-AP MLD being allowed to select the at least one of the P2P links, receive, from the second non-AP MLD over the at least one of the P2P links, the EMLMR start frame.
8. 8 . The first non-AP MLD of claim 1 , wherein: the transceivers are each further configured to form a link with a corresponding AP of an AP MLD, wherein at least a subset of the links are also EMLMR links configured to operate in the EMLMR mode of operation, the subset of links that are EMLMR links are different from the subset of links that are P2P EMLMR links, the processor is further configured to transition the first non-AP MLD into the EMLMR mode of operation for communication with the AP MLD over the EMLMR links, and at least another of the first STAs is configured to participate in an EMLMR frame exchange with the corresponding AP of the AP MLD over at least one of the links while the P2P EMLMR frame exchange is ongoing.
9. 9 . The first non-AP MLD of claim 1 , wherein: the transceivers are each further configured to form a link with a corresponding AP of an AP MLD, wherein at least a subset of the links are also EMLMR links configured to operate in the EMLMR mode of operation, some of the subset of links that are EMLMR links are also P2P EMLMR links, the processor is further configured to transition the first non-AP MLD into the EMLMR mode of operation for communication with the AP MLD over the EMLMR links, and at least another one of the first STAs is configured to participate in an EMLMR frame exchange with the corresponding AP of the AP MLD over at least one of the links such that the EMLMR frame exchange does not overlap in time with the P2P EMLMR frame exchange.
10. 10 . A method of wireless communication performed by a first non-access point (AP) multi-link device (MLD) that comprises first stations (STAs): transitioning the first non-AP MLD into an enhanced multi-link multi-radio (EMLMR) mode of operation for peer-to-peer (P2P) communication over P2P links that are formed between the first STAs and corresponding second STAs of a second non-AP MLD, wherein at least a subset of the P2P links are also EMLMR links configured to operate in the EMLMR mode of operation for P2P communication; transmitting, to the second non-AP MLD over the at least one of the P2P links, an EMLMR start frame as an indication that the at least one of the P2P links is selected for a P2P EMLMR frame exchange; or receiving, from the second non-AP MLD over the at least one of the P2P links, the EMLMR start frame; and participating, via at least one of the first STAs, in the P2P EMLMR frame exchange with the corresponding second STA of the second non-AP MLD over at least one of the P2P links.
11. 11 . The method of claim 10 , further comprising: generating a capability indication message that indicates that the first non-AP MLD supports the EMLMR mode of operation for P2P communication over the P2P links; and transmitting the capability indication message to the second non-AP MLD.
12. 12 . The method of claim 11 , wherein: links are formed between each of the first STAs and a corresponding AP of an AP MLD and at least a subset of the links are also EMLMR links configured to operate in the EMLMR mode of operation for communication with the AP MLD, and the capability indication message is one of: an EML operating mode notification frame (EOMNF) that includes an indication of the P2P links that are capable of the EMLMR mode of operation for P2P communication; or a basic multi-link element that includes the indication of the P2P links that are capable of the EMLMR mode of operation for P2P communication.
13. 13 . The method of claim 10 , further comprising: one of: transmitting, to the second non-AP MLD, an EOMNF that includes an indication to transition into the EMLMR mode of operation for P2P communication and receiving, from the second non-AP MLD, an acknowledgement of the EOMNF, or receiving, from the second non-AP MLD, the EOMNF and transmitting, to the second non-AP MLD, the acknowledgement of the EOMNF; and transitioning the first non-AP MLD into the EMLMR mode of operation for P2P communication over the P2P links after the receipt or the transmission of the acknowledgement.
14. 14 . The method of claim 10 , wherein: one of the first non-AP MLD or the second non-AP MLD is allowed to initiate transition into the EMLMR mode of operation for P2P communication, and the method further comprises: one of: based on the first non-AP MLD being allowed to initiate the transition, transmitting, to the second non-AP MLD, an EOMNF that includes an indication to transition into the EMLMR mode of operation for P2P communication and receiving, from the second non-AP MLD, an acknowledgement of the EOMNF, or based on the second non-AP MLD being allowed to initiate the transition, receiving, from the second non-AP MLD, the EOMNF and transmitting, to the second non-AP MLD, the acknowledgement of the EOMNF; and transitioning the first non-AP MLD into the EMLMR mode of operation for P2P communication over the P2P links after the receipt or the transmission of the acknowledgement.
15. 15 . The method of claim 14 , wherein: the one of the first non-AP MLD or the second non-AP MLD that is allowed to initiate the transition is: pre-determined based on relative simultaneous transmit and receive (STR) capabilities of the non-AP MLDs, or determined during a setup procedure for the P2P links that is conducted by the first and second non-AP MLDs.
16. 16 . The method of claim 10 , wherein: one of the first non-AP MLD or the second non-AP MLD is allowed to select the at least one of the P2P links for the P2P EMLMR frame exchange, and the method further comprises: before the P2P EMLMR frame exchange, based on the first non-AP MLD being allowed to select the at least one of the P2P links, transmitting, to the second non-AP MLD over the at least one of the P2P links, an EMLMR start frame as an indication that the at least one of the P2P links is selected for the P2P EMLMR frame exchange; or before the P2P EMLMR frame exchange, based on the second non-AP MLD being allowed to select the at least one of the P2P links, receiving, from the second non-AP MLD over the at least one of the P2P links, the EMLMR start frame.
17. 17 . The method of claim 10 , wherein: links are formed between each of the first STAs and a corresponding AP of an AP MLD and at least a subset of the links are also EMLMR links configured to operate in the EMLMR mode of operation for communication with the AP MLD, the subset of links that are EMLMR links are different from the subset of links that are P2P EMLMR links, and the method further comprises: transitioning the first non-AP MLD into the EMLMR mode of operation for communication with the AP MLD over the EMLMR links; and participating, via at least another of the first STAs, in an EMLMR frame exchange with the corresponding AP of the AP MLD over at least one of the links while the P2P EMLMR frame exchange is ongoing.
18. 18 . The method of claim 10 , wherein: links are formed between each of the first STAs and a corresponding AP of an AP MLD and at least a subset of the links are also EMLMR links configured to operate in the EMLMR mode of operation for communication with the AP MLD, some of the subset of links that are EMLMR links are also P2P EMLMR links, and the method further comprises: transitioning the first non-AP MLD into the EMLMR mode of operation for communication with the AP MLD over the EMLMR links; and participating, via at least another of the first STAs, in an EMLMR frame exchange with the corresponding AP of the AP MLD over at least one of the links such that the EMLMR frame exchange does not overlap in time with the P2P EMLMR frame exchange.
19. 19 . An access point (AP) multi-link device (MLD), comprising: APs, each comprising a transceiver configured to form a link with a corresponding first station (STA) of a first non-AP MLD, wherein: at least a subset of the links are also enhanced multi-link multi-radio (EMLMR) links configured to operate in an EMLMR mode of operation, and the first non-AP MLD has formed peer-to-peer (P2P) links that are also EMLMR links between the first STAs and corresponding second STAs of a second non-AP MLD; and a processor operably coupled to the APs, the processor configured to transition the AP MLD into the EMLMR mode of operation for communication with the first non-AP MLD over the EMLMR links, wherein at least one of the APs is configured to participate in an EMLMR frame exchange with the corresponding first STA of the first non-AP MLD over at least one of the EMLMR links while the P2P EMLMR frame exchange is ongoing.
20. 20 . The AP MLD of claim 19 , wherein: the subset of links that are EMLMR links are different from the links that are P2P EMLMR links, and the at least one of the APs is configured to participate in the EMLMR frame exchange with the corresponding first STA of the first non-AP MLD over the at least one of the EMLMR links while a P2P EMLMR frame exchange is ongoing between another of the first STAs and the corresponding second STA of the second non-AP MLD over at least one of the P2P links.

Description

CROSS-REFERENCE TO RELATED APPLICATION AND CLAIM OF PRIORITY This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No. 63/341,855 filed on May 13, 2022, which is hereby incorporated by reference in its entirety. TECHNICAL FIELD This disclosure relates generally to wireless communications systems that include multi-link devices. Embodiments of this disclosure relate to methods and apparatuses for facilitating the use of enhanced multi-link multi-radio operation for peer-to-peer communication between multi-link devices in a wireless local area network communications system. BACKGROUND Wireless local area network (WLAN) technology allows devices to access the internet in the 2.4 GHz, 5 GHz, 6 GHz, or 60 GHz frequency bands. WLANs are based on the Institute of Electrical and Electronic Engineers (IEEE) 802.11 standards. The IEEE 802.11 family of standards aim to increase speed and reliability and to extend the operating range of wireless networks. Next generation extremely high throughput (EHT) WI-FI systems, e.g., IEEE 802.11be, support multiple bands of operation, called links, over which an access point (AP) and a non-AP device can communicate with each other. Thus both the AP and non-AP device may be capable of communicating on different bands/links, which is referred to as multi-link operation (MLO). The WI-FI devices that support MLO are referred to as multi-link devices (MLDs). With MLO, it is possible for a non-access point (non-AP) MLD to discover, authenticate, associate, and set up multiple links with an AP MLD. Channel access and frame exchange is possible on each link that is set up between the AP MLD and non-AP MLD. For each link, a non-AP MLD indicates a set of supported maximum number of spatial streams (NSS) and modulation and coding schemes (MCS) in the “EHT-MCS Map” subfield of the “Supported EHT MCS and NSS Set” field of the EHT capabilities element. This is referred to as the link-specific “Basic MCS and NSS”. The component of an MLD that is responsible for transmission and reception on one link is referred to as a station (STA). In several embodiments of non-AP MLDs, transmission on one of the links can cause limitations or impairments on the STAs of the non-AP MLD operating other links. For example, in one class of non-AP MLDs, a pair of links can form a non-simultaneous transmit and receive (NSTR) pair. In an NSTR pair of links, transmission on one link by a STA of the non-AP MLD can cause a very high self-interference at the STA of the non-AP MLD operating on the other link of the NSTR pair. Thus, during a transmission on one link by a non-AP MLD, the STA on the other link may be incapable of sensing the channel occupancy and its network allocation vector (NAV) timer may become outdated, causing a loss of medium synchronization. The non-AP MLDs in 802.11be can have different capabilities in terms of multi-link operation. The current specification defines two special kinds of multi-link operations, namely, Enhanced Multi-Link Single-Radio Operation (EMLSR) and Enhanced Multi-Link Multi-Radio Operation (EMLMR). Many 802.11be non-AP MLDs may only have a single radio. Enhanced Multi-Link Single Radio (EMLSR) enables a multi-link operation with a single radio. With EMLSR operation, such a non-AP MLD can achieve throughput enhancement with reduced latency—a performance close to concurrent dual radio non-AP MLDs. EMLSR mode may also be implemented on multi-radio MLDs to improve channel access capability with limited hardware cost and power consumption or to improve spectral efficiency. In EMLSR mode, a multi-radio non-AP device behaves like a single radio device that can perform channel sensing and reception of elementary packets on multiple bands/links simultaneously but can perform reliable data communication on only one link at a time. Thus, by opportunistically selecting a link for data communication where it wins the channel contention, EMLSR can improve system spectral efficiency. EMLMR operation is another mode of operation newly defined in the IEEE 802.11be specification. With the EMLMR mode of operation, it is possible for an MLD with multiple radios to move transmit (TX)/receive (RX) chains from one link (e.g., a first link) to another link (e.g., a second link) of the same MLD, essentially increasing the spatial stream capability of the second link. SUMMARY Embodiments of the present disclosure provide methods and apparatuses for facilitating the use of EMLMR operation for peer-to-peer (P2P) communications between MLDs in a wireless local area network. In one embodiment, a non-AP MLD is provided, comprising STAs and a processor operably coupled to the STAs. The STAs each comprise a transceiver configured to form a P2P link with a corresponding second STA of a second non-AP MLD. At least a subset of the P2P links are also EMLMR links configured to operate in an EMLMR mode of operation for P2P communication. The processor is configured to tra