US20180206143A1

US20180206143A1 - Management procedure in multi-link aggregation

Info

Publication number: US20180206143A1
Application number: US15/872,744
Authority: US
Inventors: Abhishek Pramod PATIL; George Cherian; Yan Zhou; Alfred Asterjadhi; Venkata Ramanan Venkatachalam Jayaraman; Simone Merlin
Original assignee: Qualcomm Inc
Current assignee: Qualcomm Inc
Priority date: 2017-01-19
Filing date: 2018-01-16
Publication date: 2018-07-19
Also published as: WO2018136522A1; WO2018136516A1; WO2018136519A1; US20180205502A1; US11722946B2; CN110199494B; CN110199494A; WO2018136520A1; US10856203B2; TW201832608A; US20230319676A1; US20180206174A1; US20180206284A1; EP3571800A1; CN110199549A; WO2018136521A1; US20210051563A1; TWI749146B; CN110199549B; US20180206190A1

Abstract

Methods, systems, and devices for wireless communication are described. The described techniques may increase throughput of a wireless network, improve utilization of available channels, or provide other benefits. For example, the ability for a single traffic flow to span across different channels may increase the capacity of the network, may reduce communication latency, etc. In accordance with aspects of the present disclosure, a wireless device supporting multi-link communication may identify an anchor link and one or more supplementary links. For example, the anchor link may provide reliable communications while the supplementary links may provide increased throughput relative to the anchor link As an example, the anchor link may be dedicated for use to communicate management or control information, as well as data, while the supplementary links in the multi-link session may be used to communicate data according to the control and management information transmitted on the anchor link.

Description

CROSS REFERENCES

The present application for patent claims priority to U.S. Provisional Patent Application No. 62/448,326 to Zhou et. al., titled “WI-FI MULTICHANNEL AGGREGATION,” filed Jan. 19, 2017, assigned to the assignee hereof, which is hereby incorporated by reference in its entirety.

BACKGROUND

The following relates generally to wireless communication, and more specifically to management procedures in multi-channel aggregation.
Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). A wireless network, for example a wireless local area network (WLAN), such as a Wi-Fi (i.e., Institute of Electrical and Electronics Engineers (IEEE) 802.11) network may include an access point (AP) that may communicate with one or more stations (STAs) or mobile devices. The AP may be coupled to a network, such as the Internet, and may enable a mobile device to communicate via the network (or communicate with other devices coupled to the access point). A wireless device may communicate with a network device bi-directionally. For example, in a WLAN, a STA may communicate with an associated AP via downlink and uplink. The downlink (or forward link) may refer to the communication link from the AP to the STA, and the uplink (or reverse link) may refer to the communication link from the STA to the AP.
Devices in a WLAN may communicate over unlicensed spectrum, which may be a portion of spectrum that includes frequency bands traditionally used by Wi-Fi technology, such as the 5 GHz band, the 2.4 GHz band, the 60 GHz band, the 3.6 GHz band, and/or the 900 MHz band. The unlicensed spectrum may also include other frequency bands. The wireless connection between an AP and STA may be referred to as a channel or link. Users may access these radio frequency spectrum bands using various contention-based protocols (e.g., as specified by one or more versions of IEEE 802.11). Each band (e.g., the 5 GHz band) may contain multiple channels (e.g., each spanning 20 MHz in frequency), each of which may be usable by an AP or STA. A channel may support multiple connections (e.g., between multiple STAs and the AP) in a multiple access configuration (e.g., code division multiple access (CDMA)). In some cases, the load or demand on one channel may be low at any particular instant, while the load or demand may be high on other channels. Improved methods for allocating data flows between available channels may thus be desired. Multi-link operations may result in increased power consumption, for example because the AP and/or STA are monitoring multiple and numerous links for control or management signaling.

SUMMARY

The described techniques relate to improved methods, systems, devices, or apparatuses that support management procedures in multi-channel aggregation (which may alternatively be referred to as multi-link aggregation). The described techniques may increase throughput of a wireless network, improve utilization of available channels, or provide other benefits. For example, the ability for a single traffic flow (e.g., an internet protocol (IP) flow) to span across different channels may increase the capacity of the network, may reduce communication latency, etc. In accordance with aspects of the present disclosure, a wireless device (e.g., an AP) supporting multi-link communication may identify an anchor link and one or more supplementary links. For example, the anchor link may provide reliable communications (e.g., by operating at a lower radio frequency (RF) spectrum band) while the supplementary links may provide increased throughput relative to the anchor link (e.g., by operating in a higher RF spectrum band with greater available bandwidth). As an example, the anchor link may be used to communicate management or control information (e.g., beacons, management frames, scheduling information, etc.), while the supplementary links in the multi-link session may be used to communicate data. For example, the anchor link may be dedicated for the transmission of control or management frames, while the supplementary links may transmit data frames, but not data or management frames. In some cases, the anchor link may also be one of the wireless links used to transmit data frames in the multi-link session. In other cases, the anchor link may be a different wireless link. In some examples, the anchor link may additionally or alternatively support association procedures, or allow a wireless device to transmit, broadcast, or otherwise advertise aggregation capability information.
A method of wireless communication is described. The method may include identifying an anchor link dedicated to the communication of control and management frames for a multi-link session, receiving a control or management frame from second wireless device over the identified anchor link, and communicating in parallel between the first wireless device and the second wireless device over plurality of wireless links of the multi-link session based at least in part on the control or management frame.
An apparatus for wireless communication is described. The apparatus may include means for identifying an anchor link dedicated to the communication of control and management frames for a multi-link session, means for receiving a control or management frame from second wireless device over the identified anchor link, and means for communicating in parallel between the first wireless device and the second wireless device over plurality of wireless links of the multi-link session based at least in part on the control or management frame.
Another apparatus for wireless communication is described. The apparatus may include a processor, memory in electronic communication with the processor, and instructions stored in the memory. The instructions may be operable to cause the processor to identify an anchor link dedicated to the communication of control and management frames for a multi-link session, receive a control or management frame from second wireless device over the identified anchor link, and communicate in parallel between the first wireless device and the second wireless device over plurality of wireless links of the multi-link session based at least in part on the control or management frame.
A non-transitory computer-readable medium for wireless communication is described. The non-transitory computer-readable medium may include instructions operable to cause a processor to identify an anchor link dedicated to the communication of control and management frames for a multi-link session, receive a control or management frame from second wireless device over the identified anchor link, and communicate in parallel between the first wireless device and the second wireless device over plurality of wireless links of the multi-link session based at least in part on the control or management frame.
Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for receiving, from the second wireless device, an indication of the anchor link over the anchor link, or over a second link of the plurality of wireless links different than the anchor link, or a combination thereof.
Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for receiving, from the second wireless device, an indication of the anchor link in a beacon, or a discovery transmission, or a measurement transmission, or a combination thereof.
Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for transmitting, on the identified anchor link, a request to associate with the second wireless device.
Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for receiving a response to the request to associate with the second wireless device, wherein the control or management frame received from the second wireless device comprises the response. Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for establishing the multi-link session between the first wireless device and the second wireless device based at least in part on the response.
In some examples of the method, apparatus, and non-transitory computer-readable medium described above, communicating in parallel between the first wireless device and the second wireless device over the plurality of wireless links comprises transmitting, over the anchor wireless link, data frames and the control and management frames, the anchor link comprising one of the plurality of wireless links. Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for transmitting data frames over non-anchor links of the plurality of wireless links.
Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for transmitting data frames over one or more of the plurality of wireless links. Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for receiving, over the anchor link, one or more acknowledgements in response to the transmitted data frames.
Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for measuring a signal strength for a transmission received on the anchor link, or on a second link, or a combination thereof. Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for selecting a wireless link of the plurality of wireless links for communications during the multi-link session based at least in part on the measured signal strength.
Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for transmitting one or more frames on a second link during the multi-link session. Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for determining whether the second link may be suitable for communications in parallel between the first wireless device and the second wireless device during the multi-link session based at least in part on the one or more frames transmitted on the second link.
Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for receiving an indication of a plurality of links supported by the second wireless device, including an initial anchor link. Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for identifying that the first wireless device does not support the initial anchor link. Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for transmitting, on the anchor link, an indication that the first wireless device does not support the initial anchor link. Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for establishing the multi-link session between the first wireless device and the second wireless device based at least in part on transmitting the indication that the first wireless device does not support the initial anchor link.
In some examples of the method, apparatus, and non-transitory computer-readable medium described above, identifying the anchor link comprises transmitting, to the second wireless device, an indication of a preferred anchor link of the first wireless device. Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for receiving, from the second wireless device, an indication of the anchor link to be used by the first wireless device.
In some examples of the method, apparatus, and non-transitory computer-readable medium described above, receiving the control or management frame from the second wireless device comprises receiving, on the anchor link, aggregation capability information for the second wireless device, the aggregation capability information indicating a capability of the second wireless device to communicate in parallel over the plurality of wireless links.
In some examples of the method, apparatus, and non-transitory computer-readable medium described above, the aggregation capability information comprises a capability of the second wireless device to communicate in parallel over the plurality of wireless links, or current operating parameters of the second wireless device, or a combination thereof.
In some examples of the method, apparatus, and non-transitory computer-readable medium described above, receiving the aggregation capability information further comprises receiving a beacon, or a probe response, or an association response, or a reassociation response, or a combination thereof, that includes the aggregation capability information.
Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for transmitting aggregation capability information for the first wireless device, the aggregation capability information indicating a capability of the first wireless device to communicate in parallel over the plurality of wireless links.
In some examples of the method, apparatus, and non-transitory computer-readable medium described above, transmitting the aggregation capability information comprises transmitting a probe request, or an association request, or a reassociation request, or a combination thereof, that includes the aggregation capability information.
Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for receiving, from the second wireless device, a first operational mode indicator indicating a change in a link aggregation preference for the multi-link session. Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for ortransmitting, to the second wireless device, a second operational mode indicator indicating the change in the link aggregation preference for the multi-link session.
In some examples of the method, apparatus, and non-transitory computer-readable medium described above, establishing the multi-link session between the first wireless device and the second wireless device comprises establishing a first wireless link of the plurality of wireless links between a first lower media access control (MAC) layer of the first wireless device and a first lower MAC layer of the second wireless device. Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for establishing a second wireless link between a second lower MAC layer of the first wireless device and a second lower MAC layer of the second wireless device, wherein the first lower MAC layer and the second lower MAC layer of the first wireless device may be in communication with a common upper MAC layer of the first wireless device.
In some examples of the method, apparatus, and non-transitory computer-readable medium described above, the anchor link comprises a frequency resource, or a time resource, or a spatial stream, or a portion of a packet, or a combination thereof.
In some examples of the method, apparatus, and non-transitory computer-readable medium described above, the anchor link uses a first bandwidth and a second link of the plurality of wireless links uses a second bandwidth, the second bandwidth greater than the first bandwidth.
Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for receiving, over the anchor link, one or more control or management frames to maintain a second wireless link of the plurality of wireless links, the second wireless link limited such that the second wireless link may be unable to be maintained between the apparatus and the wireless device absent the one or more control or management frames received over the anchor link.
A method of wireless communication is described. The method may include identifying an anchor link dedicated to the communication of control and management frames for a multi-link session, transmitting a control or management frame over the identified anchor link, and communicating in parallel between the first wireless device and a second wireless device over a plurality of wireless links of the multi-link session based at least in part on the control or management frame.
An apparatus for wireless communication is described. The apparatus may include means for identifying an anchor link dedicated to the communication of control and management frames for a multi-link session, means for transmitting a control or management frame over the identified anchor link, and means for communicating in parallel between the first wireless device and a second wireless device over a plurality of wireless links of the multi-link session based at least in part on the control or management frame.
Another apparatus for wireless communication is described. The apparatus may include a processor, memory in electronic communication with the processor, and instructions stored in the memory. The instructions may be operable to cause the processor to identify an anchor link dedicated to the communication of control and management frames for a multi-link session, transmit a control or management frame over the identified anchor link, and communicate in parallel between the first wireless device and a second wireless device over a plurality of wireless links of the multi-link session based at least in part on the control or management frame.
A non-transitory computer-readable medium for wireless communication is described. The non-transitory computer-readable medium may include instructions operable to cause a processor to identify an anchor link dedicated to the communication of control and management frames for a multi-link session, transmit a control or management frame over the identified anchor link, and communicate in parallel between the first wireless device and a second wireless device over a plurality of wireless links of the multi-link session based at least in part on the control or management frame.
Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for transmitting an indication of the anchor link on the anchor link, or on a second link different than the anchor link, or a combination thereof.
Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for transmitting an indication of the anchor link in a beacon, or a discovery transmission, or a measurement transmission, or a combination thereof.
Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for transmitting an indication of a plurality of links supported by the first wireless device, including an initial anchor link. Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for receiving an indication that the second wireless device does not support the initial anchor link. Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for establishing the multi-link session between the first wireless device and the second wireless device based at least in part on receiving the indication that the second wireless device does not support the initial anchor link.
Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for receiving, from the second wireless device, an indication of a preferred anchor link of the second wireless device. Some examples of the method, apparatus, and non-transitory computer-readable medium described above may further include processes, features, means, or instructions for transmitting, to the second wireless device, an indication of the anchor link to be used by the second wireless device for the association procedure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a system for wireless communication that supports management procedures in multi-channel aggregation in accordance with aspects of the present disclosure.

FIG. 2 illustrates an example of a WLAN that supports management procedures in multi-channel aggregation in accordance with aspects of the present disclosure.

FIG. 3 illustrates an example layer configuration that supports management procedures in multi-channel aggregation in accordance with aspects of the present disclosure.

FIG. 4 illustrates an example communication scheme that supports management procedures in multi-channel aggregation in accordance with aspects of the present disclosure.

FIGS. 5 and 6 illustrate example process flows that supports management procedures in multi-channel aggregation in accordance with aspects of the present disclosure.

FIGS. 7 through 9 show block diagrams of a device that supports management procedure in multi-channel aggregation in accordance with aspects of the present disclosure.

FIG. 10 illustrates a block diagram of a system including a wireless device that supports management procedure in multi-channel aggregation in accordance with aspects of the present disclosure.

FIGS. 11 through 16 illustrate methods for management procedure in multi-channel aggregation in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

Some wireless communications systems may support multiple parallel links between communicating devices (e.g., to increase throughput, to improve link efficiency, to reduce latency, etc.). A wireless link may refer to a communication path between devices and each link may support one or more channels (e.g., logical entities) that support multiplexing of data, such that during at least some duration of time, transmissions or portions of transmissions may occur over both links at the same time, either synchronously or asynchronously. The wireless links may be in the same or different radio frequency (RF) spectrum bands. Each link of a multi-link session may be associated with respective physical components (e.g., antennas, amplifiers, including power amplifiers and low noise amplifiers, etc.) and/or logical processing components (e.g., physical (PHY) layers, MAC layers, etc.) of a given wireless device, and these components may be configured to support multi-link communications. The multiple links may connect wireless devices at the MAC layer (e.g., each link may connect respective lower MAC components of communicating devices). The MAC layer may aggregate data packets from the multiple wireless links to provide to upper layers (if the wireless device is receiving) or receive from upper layers (if the wireless devices is transmitting) of the device (e.g., using multiple connections from the MAC layer to the PHY layer). Such parallel communications, while benefiting the system in terms of throughput and spectral utilization, may increase the complexity of the system. For example, these communications may require or benefit from improved management procedures to facilitate discovery, establishment, maintenance, and control of a multi-link session.
In some cases, a wireless device (e.g., a STA or AP) may use different links for a multi-link session to communicate different types of information. For example a first link, which may be referred to as an anchor link, may be used to transmit control or management information to support link discovery, establishment, and/or maintenance. In examples described below, the control or management information may include discovery information, aggregation control information, information for link set-up (e.g., association frames), link management information (e.g., management frames), link teardown information, or any combination thereof. One or more other links of the multi-link session may support data communication based at least in part on the control or management information exchanged via the anchor link. In some cases, the anchor link may be one of the wireless links of the multi-link session used to transmit data frames, in addition to control and management frames, while the remaining wireless links may be used to transmit data frames. Although described in terms of frequency, it is to be understood that the anchor concept may be generalized to other dimensions. For example, anchor information may be associated with a given time slot, may be associated with a given spatial stream, may be contained in a message preamble, etc. Thus, the described techniques generally improve reliability for control information (e.g., based on transmitting the control information over a specific link, at a given time, etc.) and increased throughput for data (e.g., based on transmitting the data over a link that supports higher throughput communications).
Aspects of the disclosure are initially described in the context of a wireless communications system. Aspects of the disclosure are then described with reference to process flow diagrams and packet allocation schemes. Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to management procedures in multi-channel aggregation
FIG. 1 illustrates a WLAN 100 (also known as a Wi-Fi network) configured in accordance with various aspects of the present disclosure. The WLAN 100 may include an AP 105 and multiple associated STAs 115, which may represent devices such as wireless communication terminals, including mobile stations, phones, personal digital assistant (PDAs), other handheld devices, netbooks, notebook computers, tablet computers, laptops, display devices (e.g., TVs, computer monitors, etc.), printers, etc. The AP 105 and the associated STAs 115 may represent a basic service set (BSS) or an extended service set (ESS). The various STAs 115 in the network are able to communicate with one another through the AP 105. Also shown is a coverage area 110 of the AP 105, which may represent a basic service area (BSA) of the WLAN 100. An extended network station associated with the WLAN 100 may be connected to a wired or wireless distribution system that may allow multiple APs 105 to be connected in an ESS.
A STA 115 may be located in the intersection of more than one coverage area 110 and may associate with more than one AP 105. A single AP 105 and an associated set of STAs 115 may be referred to as a BSS. An ESS is a set of connected BSSs. A distribution system may be used to connect APs 105 in an ESS. In some cases, the coverage area 110 of an AP 105 may be divided into sectors. The WLAN 100 may include APs 105 of different types (e.g., metropolitan area, home network, etc.), with varying and overlapping coverage areas 110. Two STAs 115 may also communicate directly via a direct wireless link 125 regardless of whether both STAs 115 are in the same coverage area 110. Examples of direct wireless links 125 may include Wi-Fi Direct connections, Wi-Fi Tunneled Direct Link Setup (TDLS) links, and other group connections. STAs 115 and APs 105 may communicate according to the WLAN radio and baseband protocol for physical and MAC layers from IEEE 802.11 and versions including, but not limited to, 802.11b, 802.11g, 802.11a, 802.11n, 802.11ac, 802.11ad, 802.11ah, 802.11ax, 802.11ay, 802.11ba, etc. In other implementations, peer-to-peer connections or ad hoc networks may be implemented within WLAN 100. Devices in WLAN 100 may communicate over unlicensed spectrum, which may be a portion of spectrum that includes frequency bands traditionally used by Wi-Fi technology, such as the 5 GHz band, the 2.4 GHz band, the 60 GHz band, the 3.6 GHz band, and/or the 900 MHz band. The unlicensed spectrum may also include other frequency bands.
In some cases, a STA 115 (or an AP 105) may be detectable by a central AP 105, but not by other STAs 115 in the coverage area 110 of the central AP 105. For example, one STA 115 may be at one end of the coverage area 110 of the central AP 105 while another STA 115 may be at the other end. Thus, both STAs 115 may communicate with the AP 105, but may not receive the transmissions of the other. This may result in colliding transmissions for the two STAs 115 in a contention based environment (e.g., carrier-sense multiple access (CSMA)/collision avoidance (CA)) because the STAs 115 may not refrain from transmitting on top of each other. A STA 115 whose transmissions are not identifiable, but that is within the same coverage area 110 may be known as a hidden node. CSMA/CA may be supplemented by the exchange of a request-to-send (RTS) packet transmitted by a sending STA 115 (or AP 105) and a clear-to-send (CTS) packet transmitted by the receiving STA 115 (or AP 105). This exchange may alert other devices within range of the sender and receiver not to transmit for the duration of the primary transmission. Thus, RTS/CTS handshake may help mitigate a hidden node problem.
In a system supporting multi-link aggregation (which may also be referred to as multi-channel aggregation), some of the traffic associated with a single STA 115 may be transmitted across multiple parallel communication links 120 (which may also be referred to as “links” or “wireless links” herein). Multi-link aggregation may thus provide a means to increase network capacity and maximize the utilization of available resources. In some cases, each communication link 120 for a given wireless device may be associated with a respective radio of the wireless device (e.g., where a radio comprises transmit/receive chains, physical antennas, signal processing components, etc.). Multi-link aggregation may be implemented in a number of ways. As a first example, the multi-link aggregation may be packet-based. In packet-based aggregation, frames of a single traffic flow (e.g., all traffic associated with a given traffic identifier (TID)) may be sent in parallel across multiple communication links 120 (e.g., on multiple channels). In some cases, the multiple communication links 120 may operate in the same RF spectrum band (e.g., each link may be in the 5 GHz band, and use channels in the 5 GHz band). In other cases, the multiple communication links 120 may be in different RF spectrum bands (e.g., one may be in the 2.4 GHz band while another is in the 5 GHz band). Each link may be associated with a different PHY layer and lower MAC layer as described with reference to FIG. 4. In such an implementation, management of the aggregation of the separate communication links 120 may be performed at a higher MAC layer. The multilink aggregation implemented at the lower MAC layers and PHY layers may be transparent to the upper layers of the wireless device.
As another example, the multi-link aggregation may be flow-based. In flow-based aggregation, each traffic flow (e.g., all traffic associated with a given TID) may be sent using one of multiple available communication links 120. As an example, a single STA 115 may access a web browser while streaming a video in parallel. The traffic associated with the web browser access may be communicated over a first channel of a first communication link 120 while the traffic associated with the video stream may be communicated over a second channel of a second communication link 120 in parallel (e.g., at least some of the data may be transmitted on the first channel concurrent with data transmitted on the second channel). In some examples, the transmissions on the first communication link 120 and the second communication link 120 may be synchronized. In other examples, the transmissions may be asynchronous. As described above, the channels may belong to the same RF band or to different RF bands. In the case of three communication links 120 (e.g., or other numbers of communication links greater than two), all three communication links 120 may support operation over the same RF band (e.g., all three in the 5 GHz RF band). In other cases, two communication links 120, but not the third, may support operation over the same RF band (e.g., two links in the 5 GHz RF band, and one link in the 2.4 GHz RF band). Or, in still other cases each of the three communication links 120 may support operation for a separate RF band. In some cases, flow-based aggregation may not use cross-link packet scheduling and reordering (e.g., which may be used to support packet-based aggregation). Alternatively, in the case of a single flow (e.g., in the case that the STA 115 simply attempts to access a web browser), aggregation gain may not be available.
In other embodiments, a hybrid of flow-based and packet-based aggregation may be employed. As an example, a device may employ flow-based aggregation in situations in which multiple traffic flows are created and may employ packet-based aggregation in other situations. The decision to switch between multi-link aggregation techniques (e.g., modes) may additionally or alternatively be based on other metrics (e.g., a time of day, traffic load within the network, available battery power for a wireless device, etc.). It is to be understood that while aspects of the preceding are described in the context of a multi-link session involving two (or more) communication links 120, the described concepts may be extended to a multi-link session involving multiple direct wireless links 125.
To support the described multi-link aggregation techniques, APs 105 and STAs 115 may exchange supported aggregation capability information (e.g. supported aggregation type, supported frequency bands, etc.). In some cases, the exchange of information may occur via a beacon signal, a probe association request or a probe association response, dedicated action frames, an operating mode indicator (OMI), etc. In some cases, an AP 105 may designate a given channel in a given band as an anchor link (e.g., the wireless link on which it transmits beacons, management frames, control information, association information, etc., to support the discovery, establishment, and/or maintenance of wireless links used to multi-link aggregation, such as during a multi-link session between wireless devices). In this case, the AP 105 may transmit beacons (e.g., which may contain less information) on other channels or links for discovery purposes.
Although described as being frequency-based, the anchor link could additionally or alternatively be time-based (e.g., an AP 105 may transmit its beacon during a certain time interval on one or more links). For example, the AP 105 may designate a time period for transmission of control information over one or more links and may employ various techniques to provide improved reliability to the control information in the time interval (e.g., may use a more robust modulation and coding scheme (MCS), may increase a transmission power, etc.). Outside of the time interval, the AP 105 may employ techniques that prioritize data throughput over the one or more links.
In some examples, the anchor link may operate in a lower RF frequency band than the other links used in the multi-link session. For example, the anchor link may operate in a 2.4 GHz or 900 MHz band to increase the range, power, or signal quality associated with transmissions on the anchor link, relative to other wireless links that may operate at a 5 GHz or 60 GHz band associated with higher data throughputs, but relatively shorter ranges. For example, links in a higher RF band (e.g., the 60 GHz band) may be susceptible to the directionality of the antennas at the communicating devices on both sides of the links. The performance of such links may degrade if either device moves (even slightly). Responsive to such degradations, the devices may perform beam training to realign the link between the devices. During such beam training, the link may be unavailable. Thus, in systems in which a 60 GHz link (e.g., or 5 GHz link, etc.) serves as an auxiliary link to an anchor link in a lower RF band (e.g., which may provide more reliable communications), the 60 GHz link may provide higher throughput (e.g., under certain communication conditions) while the anchor link provides a stable link for discovery, link setup, exchange of control and management information, exchange of data traffic (e.g., at a lower data rate than provided by the auxiliary link), etc.
Similar techniques may be employed for technologies other than RF communications, such as light communications, which may work over short distances and/or concentrate energy in a small focused beam and/or may support a wireless link that may communicate between wireless devices in only one direction (e.g., only uplink, or only downlink, or only one direction between peer devices). Light communications (e.g., visible light communication (VLC) and other similar technologies) may benefit from auxiliary communications over a secondary link that rely on a reliable anchor link. For example, light communication (or similar communications) may be transmitted from an overhead light to a wireless device (e.g., downlink communication using a light emitting diode (LED) lamp, etc., to a mobile device) but may not support uplink communication from the wireless device to the overhead light (e.g. the LED lamp may be able to receive RF transmissions, but not VLC transmissions). Such communications may benefit from an anchor link (e.g., a 2.4 GHz link or 5 GHz link), which serves as the uplink (reverse link) to the downlink light communications. For example, the anchor link may carry acknowledgements on the uplink in response to the data transmitted by the overhead light on the downlink. In other examples, the anchor link may carry scheduling information, etc., for the transmissions using light communication from the overhead light.
In some examples, in multi-link aggregation, each link may use its own transmit queue. In other examples, a common transmit queue may be used across the links. In some examples, each link may have a unique transmitter address (TA) and receiver address (RA). In other examples, the TA and RA may be common across the multiple links used for multi-link aggregation. In other examples, one or more of a sequence number (SN), frame number (FN), and/or packet number (PN) may be common across the communication links. Other items that may be common (or different) across two or more of the links include encryption keys, MAC packet data unit (MPDU) generation, aggregated MAC service data unit (AMSDU) constraints, fragment size, reordering, replay check, and/or de-fragmentation techniques. In other examples, encryption keys may be per-link.
In various examples, block acknowledgements (BAs) may be sent in response to multi-link transmissions. A BA may refer to an acknowledgment (ACK) for multiple MPDUs sent together (e.g., an ACK for a block of MPDUs). The transmitting device (e.g., the device requesting the BA) and the receiving device (e.g., the device transmitting the BA) may establish a BA session (also known as a BA agreement) for during a setup phase, negotiating an agreement regarding the terms and capabilities for the BA session (e.g., using an add BA (ADDBA) request and response procedure). The transmitting device and receiving device may exchange capability information such as BA size, buffer size, window size (e.g., a sliding window), and/or policy, and then agree on the common parameters for each of the receiving device and the transmitter device to use. The BA agreement may be later torn down (e.g., using a delete BA (DELBA) request).
Both the transmitting device and the receiving device may maintain a sliding window (e.g., a BA window), and may have previously negotiated the size of the BA. For example, a BA session may have a BA size of 64 MPDUs (e.g., other BA size examples may include 256 MPDUs, 1024 MPDUs, etc.). In such cases, a transmitting device may transmit 64 MPDUs followed by a block acknowledgment request (BAR). In response to the BAR, the receiving device may, upon reception of the 64 MPDUs and the BAR, transmit a BA to the transmitting device. The BA may indicate whether all 64 MPDUs were received correctly, which MPDUs are missing, etc. In some cases, a BA may be used to indicate the longer BA window, or a capability exchange or agreement defining the larger BA window may also be sent. In other examples, a single SN may be used, but with multiple scoreboards (e.g., one scoreboard per channel or link), or with a common, global scoreboard as well as per-link scoreboards. Multi-link aggregation (e.g., flow-based and/or packet-based) may increase network capacity by efficiently allocating utilization of multiple links.
FIG. 2 illustrates an example of a WLAN 200 that supports management procedures in multi-channel aggregation in accordance with aspects of the present disclosure. In some examples, WLAN 200 may implement aspects of WLAN 100. A wireless connection between AP 105-a and STA 115-a may be referred to as a link 205 or a communication link, and each link 205 may include one or more channels. As an example, WLAN 200 may support multi-link aggregation such that AP 105-a and STA 115-a may communicate in parallel over two or more links (e.g., link 205-a and link 205-b). STA 115-a may thus receive packets (e.g., MPDUs) over both link 205-a and link 205-b from AP 105-a. Such parallel communications 210-a and 210-b over the two or more links may be synchronized or asynchronous, and may be uplink, or downlink, or a combination of uplink and downlink during a particular duration of time. As described above, the parallel communications 210-a and 210-b over the two or more links 205-a and 205-b may occur between two STAs 115 (e.g., which may be referred to as sidelink communication) without deviating from the scope of the present disclosure.
Such multi-link aggregation may provide multiple benefits to WLAN 200. For example, multi-link aggregation may improve UPT (e.g., by quickly flushing per-user transmit queues). Similarly, multi-link aggregation may improve throughput for WLAN 200 by improving utilization of available channels (e.g., by increasing trunking gains). That is, multi-link aggregation may increase spectral utilization and may increase the bandwidth-time product. Networks that do not support multi-link aggregation may experience under-utilization of spectrum in non-uniform (e.g., bursty) traffic conditions. For example the communication load over a given link 205 (e.g., link 205-a) may be low at any particular instant, whereas the demand may be high for another link 205 (e.g., link 205-b). By allowing a single traffic flow (e.g., a single internet protocol (IP) flow) to span across different links 205, the overall network capacity may be increased.
Further, multi-link aggregation may enable smooth transitions between multi-band radios (e.g., where each radio may be associated with a given RF band) and/or enable a framework to setup separation of control channels and data channels. Other benefits of multi-link aggregation include reducing the ON time of a modem, which may benefit a wireless device in terms of power consumption though the final power-saving gains may in some cases depend on other factors including processing requirements, RF bandwidth, etc. Multi-link aggregation additionally increases multiplexing opportunities in the case of a single BSS. That is, multi-link aggregation may increase the number of users per multiplexed transmission served by the multi-link AP 105-a.
In some cases, multi-link aggregation may be supported (including initiated) through signaling between STA 115-a and AP 105-a (or a peer STA 115). As an example, STA 115-a may indicate to AP 105-a (or the peer STA 115) whether it supports multi-link aggregation. For example, STA 115-a may indicate that it supports multi-link aggregation in general, for a particular RF spectrum band, for a link 205 of a given RF spectrum band, etc. Such signaling could be static (e.g., in the form of beacons, probes, association or re-association frames, etc.), semi-static, or dynamic (e.g., via OMI or other similar operational parameters). In some cases, AP 105-a (e.g., or the peer STA 115) may decide whether to aggregate communications with STA 115-a based at least in part on the capabilities advertised by STA 115-a. In some cases, such aggregation capability information may be communicated via an anchor link, as described further below.
In some example aggregation architectures, all TIDs (e.g., or flow IDs or frame types) may be aggregated over link 205-a and link 205-b (e.g., which may be an example of packet-based aggregation). That is, parallel communications 210-a and 210-b may each have at least one packet having a common TID. Packet-based aggregation may provide improvements in UPT, latency, and total throughput (e.g., even for the case of a single traffic flow). In some cases, links 205-a and 205-b may have independent PHY and lower MAC operations (e.g., CSMA) while aggregation is performed at an upper MAC layer, as described further below.
In some aspects, link 205-a may be designated as an anchor link (e.g., designated by AP 105-a). For example, AP 105-a may transmit beacons (e.g., or management frames, beacon frames, or other control information) via link 205-a. In some examples, STA 115-a may detect the presence of AP 105-a (and in some cases establish association with AP 105-a) on link 205-a. AP 105-a may additionally transmit beacons on other channels (e.g., supported by link 205-b) that it operates on. For example, such beacons may be for discovery or measurement purposes. In aspects, beacons on other links (e.g., link 205-b) may be mini-beacons, such as a fast initial link setup (FILS) discovery frame or a measurement pilot frame. Such mini-beacons may indicate the presence of the anchor link.
AP 105-a may indicate its capabilities (and, in some cases, current operating parameters) via beacons, probe responses, association frames, re-association frames, and the like on its anchor link (e.g., link 205-a). Similarly, STA 115-a may advertise its capabilities via association requests or via probe request frames on link 205-a. In some cases, STA 115-a may not support communications on the RF band associated with link 205-a but may support communications via link 205-b (e.g., at least one other RF band advertised by AP 105-a). STA 115-a may indicate its aggregation capability via a probe request message sent to AP 105-a via link 205-b. In such cases, AP 105-a may support association procedures for STA 115-a via link 205-b, and may configure link 205-b as the anchor link for STA 115-a. That is, AP 105-a may transmit management and/or control frames for STA 115-a via link 205-b (e.g., in addition to or instead of supporting anchor link communications for other STAs 115 via link 205-a).
In some cases, the anchor link may not be fixed (i.e., determined by AP 105-a) but may instead be negotiated per association (e.g., based on a capability or preference of STA 115-a). That is, STA 115-a may indicate (e.g., during association) a preferred anchor link, which (if located in an RF band supported by AP 105-a) may be designated as the anchor link for that association procedure. In such cases, management frames, control frames, etc., may be exchanged on the anchor link that AP 105-a has assigned to a particular association.
In some examples, the anchoring concept may be generalized to other dimensions. For example, AP 105-a may indicate a time slot to be used for anchor link operations, may use synchronization signals for anchor link operations, may use portions of transmitted packets for anchor link operations, or the like. For example, AP 105-a may append control information or management information for one or more STAs 115 to frames sent to STA 115-a. In some examples, the control information may be included in a modified preamble (e.g., or some other field) of the packets. Additionally or alternatively, the anchor link operations may be tied to a given spatial stream (e.g., may be associated with transmissions over a given antenna port).
Different RF bands may be associated with different ranges of communication in addition to other radio characteristics. For example, higher RF bands may be associated with shorter range communications (e.g., the communication range of links 205 in the 5 GHz band may be shorter than the communication range of links 205 in the 2.4 GHz band). For example, links 205 in the 5 GHz band or the 60 GHz band (e.g., or other relatively high RF bands) may be based on beam training to align the links 205 between communicating devices. Communications over such links 205 may degrade if either device moves, such that these communications may benefit from the availability of a reliable anchor link (e.g., to carry control information, link setup information, etc.). If links 205 that are available for aggregation belong to different RF bands, one or more schemes outlined below may be used for selecting an appropriate anchor link 205. In some cases, STA 115-a may determine (e.g., based on a received signal strength indicator (RSSI) of a beacon received on an anchor link) whether it can establish a link 205 on another RF band. For example, a strong RSSI may indicate that AP 105-a (e.g., or another STA in the case of sidelink communications) is in close range and may permit aggregation on higher RF bands. As an example, such determinations may be based on empirical curves (e.g., based on prior experience) or otherwise dynamically determined by STA 115-a.
Additionally or alternatively, in cases in which AP 105-a transmits beacons (or mini-beacons) on other RF bands that it supports, STA 115-a may use these beacons for measurement to determine if it can establish a link 205 on that RF band. As an example, a suitable link 205 may be established in a given RF band only if the beacon on that RF band satisfies an RSSI constraint (e.g., exceeds a given RSSI threshold). In some examples, AP 105-a and STA 115-a may exchange frames on other RF bands supported by both to determine whether a link (e.g., link 205-b) may be established on those RF bands. By way of example, AP 105-a or STA 115-a may transmit frames on the other RF band to determine if the other device is reachable and if the RF band is suitable for aggregation. Such frames may include quality of service (QoS) null frames, null data packets (NDPs), directional multi-gigabit (DMG) beam training frames, etc. If the other device receives these frames, it may respond (e.g., with an ACK), and the devices may proceed to establish a link (e.g., link 205-b) on that RF band. In some cases, beacons on the anchor link may indicate a preferred duration of time when AP 105-a is available for channel measurement (e.g., aggregation capability exchange) on one or more supported RF bands.
In some cases, AP 105-a and STA 115-a may additionally or alternatively signal a change in aggregation support. For example, AP 105-a or STA 115-a may use an operating mode indicator (OMI) to indicate a change in channel aggregation preference. As an example, such changes in aggregation preferences may result from STA 115-a moving away (or towards) AP 105-a. In some examples, the channel conditions on one of the aggregated links 205 may deteriorate (e.g., due to overlapping basic service set (OBSS) interference or the like) such that one or both of AP 105-a and STA 115-a may prefer not to continue using the link 205 for aggregated communications. Additionally or alternatively, traffic conditions at STA 115-a may change (e.g., a communication load may decrease) such that aggregation may not provide significant benefits over non-aggregated communications. In such cases, STA 115-a may choose to reduce the number of aggregated links 205 (e.g., or terminate the multi-link session entirely).
FIG. 3 illustrates an example layer configuration 300 that supports management procedures in multi-channel aggregation in accordance with aspects of the present disclosure. Layer configuration 300 may apply to a STA 115 or an AP 105, and be for a transmitting wireless device or a receiving wireless device. It is to be understood that aspects of layer configuration 300 may represent logical constructs (e.g., such that components of layer configuration 300 may share hardware components). A wireless device may support layer configuration 300 through the use of various hardware configurations described herein.
Layer configuration 300 may include upper layers 305, a MAC layer 310, and one or more PHY layers 335 (e.g., where each PHY layer 335 may in some cases be associated with a respective link or channel). MAC layer 310 may be further divided into upper MAC layer 315 and lower MAC layer 325-a, lower MAC layer 325-b, and lower MAC layer 325-c. While three lower MAC layers 325 are illustrated, it is to be understood that upper MAC layer 315 may control (e.g., via multi-link aggregation controller 320) any suitable number of lower MAC layers 325. Signaling between a given lower MAC (e.g., lower MAC layer 325-a) and upper MAC layer 315 may be carried by connection 345. Similarly, signaling between lower MAC layer 325-a and PHY layer 335-a may be carried by connection 350 and signaling between lower MAC layer 325-a and lower MAC layer 325-b may be carried by connection 340. In some cases, the signaling for lower MAC 325-a, lower MAC layer 325-b, and lower MAC layer 325-c may be based on logic associated with respective controller 330-a, controller 330-b, and controller 330-c.
With reference to FIG. 2, lower MAC layer 325-a may be associated with link 205-a (e.g., via PHY layer 335-a) and lower MAC layer 325-b may be associated with link 205-b (e.g., via PHY layer 335-b). That is, each link 205 may have an associated lower MAC layer 325 that performs link-specific features (e.g., channel access, uplink triggered transmission procedures, multiple-input, multiple-output (MIMO) signaling, etc.) For example, lower MAC layer 325-a and lower MAC layer 325-b may independently perform enhanced distributed channel access (EDCA) countdowns on respective links 205-a and 205-b. Additionally or alternatively, lower MAC layers 325 may perform RTS/CTS procedures, perform clear channel assessment (CCA) procedures, apply a modulation and coding scheme (MCS), control a physical packet data unit (PPDU) duration, transmit sounding reference signals, etc.
Upper MAC layer 315 may provide a single-link interface to upper layers 305. For example, upper MAC layer 315 may perform management and security-related operations. Such a design may allow a single beacon from an AP 105 on a primary band to control multi-band STAs 115. Additionally or alternatively, the single upper MAC layer 315 may allow for a single association procedure to initiate the multi-link session. For example, an association procedure may be performed using a single link, but provide for capability information for multiple links, which may include the link that is being used for the association procedure. In some cases, the upper MAC layer 315 may provide signaling (e.g., OMI signaling) that allows for dynamic bandwidth control (e.g., expansion). The upper MAC layer 315 may additionally or alternatively provide a single BA space (e.g., a single BA scoreboard and sequence space) such that MPDUs may be scheduled dynamically on a per-PPDU basis for each link (e.g., such that a given MPDU may be retransmitted on a different link from that on which it was originally transmitted). In some cases, upper MAC layer 315 may handle operations related to security. For example, a pseudo-random number sequence may be assigned by upper MAC layer 315 to allow packets to be retransmitted on any link without compromising transmission security.
FIG. 4 illustrates an example of a communication scheme 400 that supports management procedures in multi-channel aggregation in accordance with various aspects of the present disclosure. In some examples, communication scheme 400 may implement aspects of WLAN 100. For example, communication scheme 400 may be implemented between a transmitting wireless device 455-a (e.g., a STA 115 or AP 105) and a receiving wireless device 455-b (e.g., a STA 115 or AP 105). Although described in the context of a single transmitting device and a single receiving device, it is to be understood that aspects of the following may be extended to communications with non-co-located APs 105 (APs 105 that are not co-located).
Communication scheme 400 includes link 435-a and link 435-b for carrying information between transmitting wireless device 455-a and receiving wireless device 455-b. In some examples, link 435-a may represent an anchor link while link 435-b represents a supplementary link (e.g., a non-anchor link of the wireless links of a multi-link aggregation session). As such, link 435-a may carry control information in addition to data, while link 435-b may carry primarily data. For example, the control information conveyed across link 435-a may be in the form of management frames or control frames handled independently from the operations of communication scheme 400 or in control fields which may be appended to packets transmitted across link 435-a. Alternatively, another link 435 may be an anchor link (e.g., for carrying control information) while link 435-a and link 435-b may each carry primarily data.
In the example illustrated by communication scheme 400, upper MAC 410 (e.g., which may be an example of upper MAC 315 described with reference to FIG. 3) may receive application data 405 as an input (e.g., in the form of MAC service data units (MSDUs)). Upper MAC 410 may in some cases attach a common SN to the MSDUs at 415 and may allocate these MSDUs to a common transmit queue 420. In some cases, these MSDUs may be encrypted at 425 before being allocated from common transmit queue 420 to one of lower Tx MAC 430-a or lower Tx MAC 430-b (e.g., which may each be examples of or implement aspects of a lower MAC 325 as described with reference to FIG. 3). In some examples, a transmitting wireless device 455-a may contain multiple common transmit queues 420, each of which is associated with a given access category. Alternatively, all access categories may share a single common transmit queue 420.
In aspects of communication scheme 400, packets of each TID of the multi-link session may be assigned to common transmit queue 420 (i.e., a transmit queue that is common across all links 435) after being assigned a common SN at 415. Such an architecture may support on-demand MSDU allocation in which MSDUs are allocated to a given link 435 when the link is ready to transmit. As an example, when link 435-a is clear for transmission (e.g., as determined by a CCA procedure performed by lower Tx MAC 430-a), lower Tx MAC 430-a may receive enough MSDUs from common transmit queue 420 to form an aggregated MPDU (AMPDU).
In some cases, lower Tx MAC 430-a and lower Tx MAC 430-b may communicate control signaling. For example, such control signaling may enable coordination of transmissions across link 435-a and link 435-b (e.g., which may serve to reduce adjacent channel interference or otherwise benefit the communications). Each lower Tx MAC 430 may form AMPDUs from the allocated MSDUs and send them over a respective link 435 (e.g., using CSMA).
A receiving wireless device 455-b may comprise lower Rx MAC 440-a and lower Rx MAC 440-b, each of which may also be an example of a lower MAC 325 described with reference to FIG. 3. Each of lower Rx MAC 440-a and lower Rx MAC 440-b may forward decoded MPDUs to a common receive queue 450. In some cases, the MPDUs may be decrypted at 445, may be reordered upon arrival at the common receive queue 450, etc. A BA may be sent per link 435 after each received PPDU based on results in common receive queue 450. Additionally or alternatively, a single BA may be sent back for both links 435 via a dedicated link (e.g., via an anchor link). After receiving the BA, common transmit queue 420 may remove the acknowledged MSDUs from the transmission buffer. Any failed (A)MSDUs may be retransmitted (e.g., on a same link 435 or another link 435), where such retransmission may be immediate in some cases.
Multi-link aggregation may additionally improve transmission reliability in some cases. Various schemes (e.g., or combinations thereof) may be employed to this end. For example, since broadcast communications are not acknowledged, they may in some cases be duplicated across multiple links 435. Additionally or alternatively, unicast traffic may be duplicated on multiple links 435. For example, the same MPDUs may be sent on link 435-a (e.g., which may be a 2.4 GHz link) and link 435-b (e.g., which may be a 5 GHz link, or another channel in the 2.4 GHz band, etc.). Because the BA is handled at upper MAC 410 at the transmitting device, an MPDU may be considered successfully transmitted if it is delivered via either of the links 435. Such a transmission scheme may be leverage the fact that each RF band is associated with a different band and radio characteristics. For example, higher RF bands generally have a shorter range of transmission (e.g., experience greater degrees of frequency-dependent fading).
By way of example, in some cases the encryption at 425 may include application of codes to a stream that is to be transmitted over the links by transmitting wireless device 455-a, which may help to improve reliability by enabling a receiving wireless device 455-b to decode the communication even if only a subset of the stream is successfully received by receiving wireless device 455-b. For example, the transmitting wireless device 455-a may duplicate some or all of the packets to the transmitted over the links. In some examples, the original and duplicated packets may be sent over the same wireless link 435 (e.g., both sets of packets over wireless link 435-a). In other examples, the original and duplicated packets may be sent over different wireless links 435 (e.g., the original set of packets over wireless link 435-a and the duplicated set of packets over wireless link 435-b). In some examples, a combination of these approaches may be used, including transmission of original and duplicated packets over three or more different links. The wireless links 435 used may also dynamically change, for example to account for varying link conditions.
Additionally or alternatively, transmission reliability may be improved through the application of encoding algorithms which increase the entropy of the data stream such that a transmission may be decoded even if only a subset of the transmitted data packets are received. By way of example, a data stream comprising Nbits of information may be encoded into a data stream containing N+k bits, and the N+k bits may be formatted into a set of packets such that, even if only a subset of the packets are successfully received, the N bits of information may be decoded. For example, a code engine (e.g., implementing a Raptor code, or other fountain code) may increase the entropy of the data stream, which may be formatted and transmitted across multiple links 435. Such a communication scheme may allow a receiver to reconstruct the original message even if only portions of the stream of packets are received. For example, if one link 435 suffers a temporary decline in communication quality such that packets transmitted during this time are unable to be successfully received, a receiving device may still successfully decode the transmitted information based on packets received over another link 435.
Some wireless systems may support a form of link-hopping where the transmission on a particular link 435 is based on a pseudo-random sequence with which both transmitter and receiver are familiar. For example, the pseudo-random sequence may be known for a particular system (e.g., may be preconfigured), may be negotiated during association, etc. Band-hopping (e.g., in addition to fountain codes) may help make the system more robust to packet loss. Additionally or alternatively, band-hopping may spread the usage across several channels, thus allowing several transmit/receive pairs to simultaneously use the same RF bands without excessive interference (e.g., may increase multiplexing opportunities). Band hopping may be within a particular link, or may occur across two or more links.
FIG. 5 illustrates an example of a process flow 500 that supports management procedures in multi-channel aggregation in accordance with various aspects of the present disclosure. In some examples, process flow 500 may implement aspects of WLAN 100. For example, process flow 500 includes wireless device 505-a and wireless device 505-b, each of which may be an example of an AP 105 or a STA 115 as described with reference to FIG. 1.
At 510, wireless device 505-a may identify an anchor link dedicated to the communication of control and management frames for a multi-link session. For example, wireless device 505-a may receive an indication of the anchor link from wireless device 505-b over the anchor link (e.g., or another link). In some cases, the indication of the anchor link may be contained in a beacon, a discovery transmission, a measurement transmission, or some combination thereof. In some cases, the wireless device 505-a may be preconfigured, or configured by a network management node or device, with identification information for the anchor link. The indication may be an identifier of the anchor link, for example a transmitter address, or a receiver address, or a traffic identifier, or a combination of these, that identifies the anchor link to wireless device 505-a. In some cases, the anchor link includes a frequency resource, a time resource, a spatial stream, a portion of a packet, or any combination thereof.
At 515, wireless device 505-a may receive a control or management frame from wireless device 505-b over the identified anchor link. For example, receiving the control or management frame may include receiving, on the anchor link, aggregation capability information for wireless device 505-b, where the aggregation capability information indicates a capability of wireless device 505-b to communicate in parallel over a plurality of wireless links. In some cases, the aggregation capability information may include a capability of wireless device 505-b to communicate in parallel over the plurality of wireless links, or current operating parameters of wireless device 505-b, or some combination thereof. In some cases, receiving the aggregation capability information includes receiving a beacon, a probe response, an association response, a reassociation response, or a combination thereof that includes the aggregation capability information.
At 520, wireless device 505-a and wireless device 505-b may establish a multi-link session. For example, wireless device 505-a and wireless device 505-b may establish a first wireless link of the plurality of wireless links between a respective first lower MAC layer of each device and establish a second wireless link of the plurality of wireless links between a respective second lower MAC layer of each device, where the first lower MAC layer and the second lower MAC layer of the first wireless device are in communication with a common upper MAC layer of the first wireless device.
FIG. 6 illustrates an example of a process flow 600 that supports management procedures in multi-channel aggregation in accordance with various aspects of the present disclosure. In some examples, process flow 600 may implement aspects of WLAN 100. For example, process flow 600 includes wireless device 605-a and wireless device 605-b, each of which may be an example of an AP 105 or a STA 115 as described with reference to FIG. 1.
At 610, wireless device 605-a may identify an anchor link dedicated to the communication of control and management frames for a multi-link session. For example, wireless device 605-a may receive an indication of the anchor link from wireless device 605-b over the anchor link (e.g., or another link). In some cases, the indication of the anchor link may be contained in a beacon, a discovery transmission, a measurement transmission, or some combination thereof. In some cases, the anchor link includes a frequency resource, a time resource, a spatial stream, a portion of a packet, or any combination thereof.
At 615, wireless device 605-a and wireless device 605-b may exchange association information. For example, wireless device 605-a may transmit, on the identified anchor link, a request to associate with wireless device 605-b and may receive a response to the request (e.g., in the form of a control or management frame). In some cases, wireless device 605-a may receive an indication of a set of links supported by wireless device 605-b, including an initial anchor link. Wireless device 605-a may identify that it does not support the initial anchor link, and may transmit (e.g., on the anchor link identified at 610) an indication that it does not support the initial anchor link. Additionally or alternatively, wireless device 605-a may transmit an indication of a preferred anchor link and receive an indication of an anchor link to be used for communications from wireless device 605-b.
At 620, wireless device 605-a and wireless device 605-b may establish a multi-link session. For example, wireless device 605-a and wireless device 605-b may establish a first wireless link of the plurality of wireless links between a respective first lower MAC layer of each device and establish a second wireless link of the plurality of wireless links between a respective second lower MAC layer of each device, where the first lower MAC layer and the second lower MAC layer of the first wireless device are in communication with a common upper MAC layer of the first wireless device. In some cases, the multi-link session may be established based at least in part on the association information exchanged at 615.
At 625, wireless device 605-a and/or wireless device 605-b may monitor one or more of the links of the multi-link session. For example, wireless device 605-a may transmit (e.g., and wireless device 605-b may monitor for) data frames, control frames, management frames, etc., over the anchor link and may transmit data frames over non-anchor links of the multi-link session. In some cases, one or both of the wireless devices may monitor for acknowledgements over the anchor link in response to the transmitted data frames. In some cases, one or both of wireless device 605-a and wireless device 605-b may measure a signal strength for a transmission received on the anchor link or may otherwise determine (e.g., based on a frame transmitted via a non-anchor link) whether one or more links of the multi-link session are suitable for supporting aggregated communications. For example, the determination may in some cases be based at least in part on the exchange of an operational mode indicator indicating a change in a link aggregation preference for the multi-link session.
FIG. 7 shows a block diagram 700 of a wireless device 705 that supports management procedure in multi-channel aggregation in accordance with aspects of the present disclosure. Wireless device 705 may be an example of aspects of a STA 115 of an AP 105 as described herein. Wireless device 705 may include receiver 710, communications manager 715, and transmitter 720. Wireless device 705 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).
Receiver 710 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to management procedure in multi-channel aggregation, etc.). Information may be passed on to other components of the device. The receiver 710 may be an example of aspects of the transceiver 1035 described with reference to FIG. 10. The receiver 710 may utilize a single antenna or a set of antennas.
Communications manager 715 may be an example of aspects of the communications manager 1015 described with reference to FIG. 10. Communications manager 715 and/or at least some of its various sub-components may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions of the communications manager 715 and/or at least some of its various sub-components may be executed by a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), an field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in the present disclosure.
The communications manager 715 and/or at least some of its various sub-components may be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations by one or more physical devices. In some examples, communications manager 715 and/or at least some of its various sub-components may be a separate and distinct component in accordance with various aspects of the present disclosure. In other examples, communications manager 715 and/or at least some of its various sub-components may be combined with one or more other hardware components, including but not limited to an I/O component, a transceiver, a network server, another computing device, one or more other components described in the present disclosure, or a combination thereof in accordance with various aspects of the present disclosure.
Communications manager 715 may identify an anchor link dedicated to the communication of control and management frames for a multi-link session. Communications manager 715 may receive a control or management frame from a second wireless device over the identified anchor link. Communications manager 715 may communicate in parallel between the first wireless device and the second wireless device over set of wireless links of the multi-link session based on the control or management frame. The communications manager 715 may also identify an anchor link dedicated to the communication of control and management frames for a multi-link session. Communications manager 715 may transmit a control or management frame over the identified anchor link. Communications manager 715 may communicate in parallel between the first wireless device and a second wireless device over a set of wireless links of the multi-link session based on the control or management frame.
Transmitter 720 may transmit signals generated by other components of the device. In some examples, the transmitter 720 may be collocated with a receiver 710 in a transceiver module. For example, the transmitter 720 may be an example of aspects of the transceiver 1035 described with reference to FIG. 10. The transmitter 720 may utilize a single antenna or a set of antennas.
FIG. 8 shows a block diagram 800 of a wireless device 805 that supports management procedure in multi-channel aggregation in accordance with aspects of the present disclosure. Wireless device 805 may be an example of aspects of a wireless device 605, a STA 115, or an AP 105 as described with reference to FIG. 7. Wireless device 805 may include receiver 810, communications manager 815, and transmitter 820. Wireless device 805 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).
Receiver 810 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to management procedure in multi-channel aggregation, etc.). Information may be passed on to other components of the device. The receiver 810 may be an example of aspects of the transceiver 1035 described with reference to FIG. 10. The receiver 810 may utilize a single antenna or a set of antennas.
Communications manager 815 may be an example of aspects of the communications manager 1015 described with reference to FIG. 10. Communications manager 815 may also include anchor link component 825, link setup controller 830, and multi-link manager 835.
Anchor link component 825 may identify an anchor link dedicated to the communication of control and management frames for a multi-link session. Anchor link component 825 may transmit, to the second wireless device, an indication of the anchor link to be used by the second wireless device for the association procedure. Anchor link component 825 may receive, from the second wireless device, an indication of the anchor link in a beacon, or a discovery transmission, or a measurement transmission, or a combination thereof. Anchor link component 825 may transmit, on the anchor link, an indication that the first wireless device does not support the initial anchor link. Anchor link component 825 may receive, from the second wireless device, an indication of the anchor link to be used by the first wireless device. Anchor link component 825 may receive, from the second wireless device, an indication of the anchor link over the anchor link, or over a second link of the set of wireless links different than the anchor link, or a combination thereof. Anchor link component 825 may transmit an indication of the anchor link on the anchor link, or on a second link different than the anchor link, or a combination thereof. Anchor link component 825 may transmit an indication of the anchor link in a beacon, or a discovery transmission, or a measurement transmission, or a combination thereof. Anchor link component 825 may receive, from the second wireless device, an indication of a preferred anchor link of the second wireless device. Anchor link component 825 may receive, over the anchor link, one or more control or management frames to maintain a second wireless link of the plurality of wireless links, the second wireless link limited such that the second wireless link is unable to be maintained between the apparatus and the wireless device absent the one or more control or management frames received over the anchor link. In some cases, identifying the anchor link includes transmitting, to the second wireless device, an indication of a preferred anchor link of the first wireless device. In some cases, the anchor link includes a frequency resource, or a time resource, or a spatial stream, or a portion of a packet, or a combination thereof. In some cases, the anchor link may occupy a first bandwidth, while one or more auxiliary links of the multi-link session occupy a second bandwidth greater than the first bandwidth.
Link setup controller 830 may receive an indication of a set of links supported by the second wireless device, including an initial anchor link. Link setup controller 830 may identify that the first wireless device does not support the initial anchor link. Link setup controller 830 may receive a control or management frame from a second wireless device over the identified anchor link, transmit an indication of a set of links supported by the first wireless device, including an initial anchor link. Link setup controller 830 may receive a response to the request to associate with the second wireless device, where the control or management frame received from the second wireless device includes the response. Link setup controller 830 may transmit, on the identified anchor link, a request to associate with the second wireless device. Link setup controller 830 may transmit aggregation capability information for the first wireless device, the aggregation capability information indicating a capability of the first wireless device to communicate in parallel over the set of wireless links. Link setup controller 830 may receive an indication that the second wireless device does not support the initial anchor link. Link setup controller 830 may transmit a control or management frame over the identified anchor link.
In some cases, receiving the control or management frame from the second wireless device includes receiving, on the anchor link, aggregation capability information for the second wireless device, the aggregation capability information indicating a capability of the second wireless device to communicate in parallel over the set of wireless links. In some cases, receiving the aggregation capability information further includes receiving a beacon, or a probe response, or an association response, or a reassociation response, or a combination thereof, that includes the aggregation capability information. In some cases, transmitting the aggregation capability information includes transmitting a probe request, or an association request, or a reassociation request, or a combination thereof, that includes the aggregation capability information. In some cases, the aggregation capability information includes a capability of the second wireless device to communicate in parallel over the set of wireless links, or current operating parameters of the second wireless device, or a combination thereof.
Multi-link manager 835 may establish the multi-link session between the first wireless device and the second wireless device based on transmitting the indication that the first wireless device does not support the initial anchor link. Multi-link manager 835 may communicate in parallel between the first wireless device and the second wireless device over set of wireless links of the multi-link session based on the control or management frame. Multi-link manager 835 may measure a signal strength for a transmission received on the anchor link, or on a second link, or a combination thereof. Multi-link manager 835 may select a wireless link of the set of wireless links for communications during the multi-link session based on the measured signal strength. Multi-link manager 835 may transmit data frames over one or more of the set of wireless links. Multi-link manager 835 may receive, over the anchor link, one or more acknowledgements in response to the transmitted data frames. Multi-link manager 835 may transmit one or more frames on a second link during the multi-link session.
Multi-link manager 835 may establish the multi-link session between the first wireless device and the second wireless device based on the response. Multi-link manager 835 may establish a second wireless link between a second lower MAC layer of the first wireless device and a second lower MAC layer of the second wireless device, where the first lower MAC layer and the second lower MAC layer of the first wireless device are in communication with a common upper MAC layer of the first wireless device. Multi-link manager 835 may transmit data frames over non-anchor links of the set of wireless links. Multi-link manager 835 may determine whether the second link is suitable for communications in parallel between the first wireless device and the second wireless device during the multi-link session based on the one or more frames transmitted on the second link.
Multi-link manager 835 may receive, from the second wireless device, a first operational mode indicator indicating a change in a link aggregation preference for the multi-link session, or may transmit, to the second wireless device, a second operational mode indicator indicating the change in the link aggregation preference for the multi-link session. Multi-link manager 835 may establish the multi-link session between the first wireless device and the second wireless device based on receiving the indication that the second wireless device does not support the initial anchor link. Multi-link manager 835 may communicate in parallel between the first wireless device and a second wireless device over a set of wireless links of the multi-link session based on the control or management frame. In some cases, communicating in parallel between the first wireless device and the second wireless device over the set of wireless links includes transmitting, over the anchor link, data frames and the control and management frames, the anchor link including one of the set of wireless links. In some cases, establishing the multi-link session between the first wireless device and the second wireless device includes establishing a first wireless link of the set of wireless links between a first lower MAC layer of the first wireless device and a first lower MAC layer of the second wireless device.
Transmitter 820 may transmit signals generated by other components of the device. In some examples, the transmitter 820 may be collocated with a receiver 810 in a transceiver module. For example, the transmitter 820 may be an example of aspects of the transceiver 1035 described with reference to FIG. 10. The transmitter 820 may utilize a single antenna or a set of antennas.
FIG. 9 shows a block diagram 900 of a communications manager 915 that supports management procedure in multi-channel aggregation in accordance with aspects of the present disclosure. The communications manager 915 may be an example of aspects of a communications manager 715, a communications manager 815, or a communications manager 1015 described with reference to FIGs. 7, 8, and 10. The communications manager 915 may include anchor link component 920, link setup controller 925, and multi-link manager 930. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses).
Anchor link component 920 may identify an anchor link dedicated to the communication of control and management frames for a multi-link session. Anchor link component 920 may transmit, to the second wireless device, an indication of the anchor link to be used by the second wireless device for the association procedure. Anchor link component 920 may receive, from the second wireless device, an indication of the anchor link in a beacon, or a discovery transmission, or a measurement transmission, or a combination thereof. Anchor link component 920 may transmit, on the anchor link, an indication that the first wireless device does not support the initial anchor link. Anchor link component 920 may receive, from the second wireless device, an indication of the anchor link to be used by the first wireless device. Anchor link component 920 may receive, from the second wireless device, an indication of the anchor link over the anchor link, or over a second link of the set of wireless links different than the anchor link, or a combination thereof. Anchor link component 920 may transmit an indication of the anchor link on the anchor link, or on a second link different than the anchor link, or a combination thereof. Anchor link component 920 may transmit an indication of the anchor link in a beacon, or a discovery transmission, or a measurement transmission, or a combination thereof. Anchor link component 920 may receive, from the second wireless device, an indication of a preferred anchor link of the second wireless device. Anchor link component 920 may receive, over the anchor link, one or more control or management frames to maintain a second wireless link of the plurality of wireless links, the second wireless link limited such that the second wireless link is unable to be maintained between the apparatus and the wireless device absent the one or more control or management frames received over the anchor link. In some cases, identifying the anchor link includes transmitting, to the second wireless device, an indication of a preferred anchor link of the first wireless device. In some cases, the anchor link includes a frequency resource, or a time resource, or a spatial stream, or a portion of a packet, or a combination thereof. In some cases, the anchor link may occupy a first bandwidth, while one or more auxiliary links of the multi-link session occupy a second bandwidth greater than the first bandwidth.
Link setup controller 925 may receive an indication of a set of links supported by the second wireless device, including an initial anchor link. Link setup controller 925 may identify that the first wireless device does not support the initial anchor link. Link setup controller 925 may receive a control or management frame from a second wireless device over the identified anchor link. Link setup controller 925 may transmit an indication of a set of links supported by the first wireless device, including an initial anchor link. Link setup controller 925 may receive a response to the request to associate with the second wireless device, where the control or management frame received from the second wireless device includes the response. Link setup controller 925 may transmit, on the identified anchor link, a request to associate with the second wireless device. Link setup controller 925 may transmit aggregation capability information for the first wireless device, the aggregation capability information indicating a capability of the first wireless device to communicate in parallel over the set of wireless links. Link setup controller 925 may receive an indication that the second wireless device does not support the initial anchor link. Link setup controller 925 may transmit a control or management frame over the identified anchor link.
In some cases, receiving the control or management frame from the second wireless device includes receiving, on the anchor link, aggregation capability information for the second wireless device, the aggregation capability information indicating a capability of the second wireless device to communicate in parallel over the set of wireless links. In some cases, receiving the aggregation capability information further includes receiving a beacon, or a probe response, or an association response, or a reassociation response, or a combination thereof, that includes the aggregation capability information. In some cases, transmitting the aggregation capability information includes transmitting a probe request, or an association request, or a reassociation request, or a combination thereof, that includes the aggregation capability information. In some cases, the aggregation capability information includes a capability of the second wireless device to communicate in parallel over the set of wireless links, or current operating parameters of the second wireless device, or a combination thereof.
Multi-link manager 930 may establish the multi-link session between the first wireless device and the second wireless device based on transmitting the indication that the first wireless device does not support the initial anchor link. Multi-link manager 930 may communicate in parallel between the first wireless device and the second wireless device over set of wireless links of the multi-link session based on the control or management frame. Multi-link manager 930 may measure a signal strength for a transmission received on the anchor link, or on a second link, or a combination thereof. Multi-link manager 930 may select a wireless link of the set of wireless links for communications during the multi-link session based on the measured signal strength. Multi-link manager 930 may transmit data frames over one or more of the set of wireless links. Multi-link manager 930 may receive, over the anchor link, one or more acknowledgements in response to the transmitted data frames.
Multi-link manager 930 may transmit one or more frames on a second link during the multi-link session. Multi-link manager 930 may establish the multi-link session between the first wireless device and the second wireless device based on the response. Multi-link manager 930 may establish a second wireless link between a second lower MAC layer of the first wireless device and a second lower MAC layer of the second wireless device, where the first lower MAC layer and the second lower MAC layer of the first wireless device are in communication with a common upper MAC layer of the first wireless device. Multi-link manager 930 may transmit data frames over non-anchor links of the set of wireless links. Multi-link manager 930 may determine whether the second link is suitable for communications in parallel between the first wireless device and the second wireless device during the multi-link session based on the one or more frames transmitted on the second link.
Multi-link manager 930 may receive, from the second wireless device, a first operational mode indicator indicating a change in a link aggregation preference for the multi-link session, or may transmit, to the second wireless device, a second operational mode indicator indicating the change in the link aggregation preference for the multi-link session. Multi-link manager 930 may establish the multi-link session between the first wireless device and the second wireless device based on receiving the indication that the second wireless device does not support the initial anchor link. Multi-link manager 930 may communicate in parallel between the first wireless device and a second wireless device over a set of wireless links of the multi-link session based on the control or management frame. In some cases, communicating in parallel between the first wireless device and the second wireless device over the set of wireless links includes transmitting, over the anchor link, data frames and the control and management frames, the anchor link including one of the set of wireless links. In some cases, establishing the multi-link session between the first wireless device and the second wireless device includes establishing a first wireless link of the set of wireless links between a first lower MAC layer of the first wireless device and a first lower MAC layer of the second wireless device.
FIG. 10 shows a diagram of a system 1000 including a device 1005 that supports management procedure in multi-channel aggregation in accordance with aspects of the present disclosure. Device 1005 may be an example of or include the components of wireless device 705, wireless device 805, a STA 115, or an AP 105 as described above, e.g., with reference to FIGS. 7 and 8. Device 1005 may include components for bi-directional voice and data communications including components for transmitting and receiving communications, including communications manager 1015, processor 1020, memory 1025, software 1030, transceiver 1035, antenna 1040, and I/O controller 1045. These components may be in electronic communication via one or more buses (e.g., bus 1010).
Processor 1020 may include an intelligent hardware device, (e.g., a general-purpose processor, a DSP, a central processing unit (CPU), a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, processor 1020 may be configured to operate a memory array using a memory controller. In other cases, a memory controller may be integrated into processor 1020. Processor 1020 may be configured to execute computer-readable instructions stored in a memory to perform various functions (e.g., functions or tasks supporting management procedure in multi-channel aggregation).
Memory 1025 may include random access memory (RAM) and read only memory (ROM). The memory 1025 may store computer-readable, computer-executable software 1030 including instructions that, when executed, cause the processor to perform various functions described herein. In some cases, the memory 1025 may contain, among other things, a basic input/output system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.
Software 1030 may include code to implement aspects of the present disclosure, including code to support management procedure in multi-channel aggregation. Software 1030 may be stored in a non-transitory computer-readable medium such as system memory or other memory. In some cases, the software 1030 may not be directly executable by the processor but may cause a computer (e.g., when compiled and executed) to perform functions described herein.
Transceiver 1035 may communicate bi-directionally, via one or more antennas, wired, or wireless links as described above. For example, the transceiver 1035 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 1035 may also include a modem to modulate the packets and provide the modulated packets to the antennas for transmission, and to demodulate packets received from the antennas. In some cases, the wireless device may include a single antenna 1040. However, in some cases the device may have more than one antenna 1040, which may be capable of concurrently transmitting or receiving multiple wireless transmissions.
I/O controller 1045 may manage input and output signals for device 1005. I/O controller 1045 may also manage peripherals not integrated into device 1005. In some cases, I/O controller 1045 may represent a physical connection or port to an external peripheral. In some cases, I/O controller 1045 may utilize an operating system such as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, or another known operating system. In other cases, I/O controller 1045 may represent or interact with a modem, a keyboard, a mouse, a touchscreen, or a similar device. In some cases, I/O controller 1045 may be implemented as part of a processor. In some cases, a user may interact with device 1005 via I/O controller 1045 or via hardware components controlled by I/O controller 1045.
FIG. 11 shows a flowchart illustrating a method 1100 for management procedure in multi-channel aggregation in accordance with aspects of the present disclosure. The operations of method 1100 may be implemented by a STA 115 or an AP 105 or its components as described herein. For example, the operations of method 1100 may be performed by a communications manager as described with reference to FIGS. 7 through 10. In some examples, a STA 115 or an AP 105 may execute a set of codes to control the functional elements of the device to perform the functions described below. Additionally or alternatively, the STA 115 or the AP 105 may perform aspects of the functions described below using special-purpose hardware.
At 1105 the STA 115 or the AP 105 may identify an anchor link dedicated to the communication of control and management frames for a multi-link session. The operations of 1105 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1105 may be performed by an anchor link component as described with reference to FIGS. 7 through 10.
At 1110 the STA 115 or the AP 105 may receive a control or management frame from a second wireless device over the identified anchor link. The operations of 1110 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1110 may be performed by a link setup controller as described with reference to FIGS. 7 through 10.
At 1115 the STA 115 or the AP 105 may communicate in parallel between the first wireless device and the second wireless device over plurality of wireless links of the multi-link session based at least in part on the control or management frame. The operations of 1115 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1115 may be performed by a multi-link manager as described with reference to FIGS. 7 through 10.
FIG. 12 shows a flowchart illustrating a method 1200 for management procedure in multi-channel aggregation in accordance with aspects of the present disclosure. The operations of method 1200 may be implemented by a STA 115 or an AP 105 or its components as described herein. For example, the operations of method 1200 may be performed by a communications manager as described with reference to FIGS. 7 through 10. In some examples, a STA 115 or an AP 105 may execute a set of codes to control the functional elements of the device to perform the functions described below. Additionally or alternatively, the STA 115 or the AP 105 may perform aspects of the functions described below using special-purpose hardware.
At 1205 the STA 115 or the AP 105 may identify an anchor link dedicated to the communication of control and management frames for a multi-link session. The operations of 1205 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1205 may be performed by an anchor link component as described with reference to FIGS. 7 through 10.
At 1210 the STA 115 or the AP 105 may receive a control or management frame from a second wireless device over the identified anchor link. The operations of 1210 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1210 may be performed by a link setup controller as described with reference to FIGS. 7 through 10.
At 1215 the STA 115 or the AP 105 may communicate in parallel between the first wireless device and the second wireless device over plurality of wireless links of the multi-link session based at least in part on the control or management frame. The operations of 1215 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1215 may be performed by a multi-link manager as described with reference to FIGS. 7 through 10.
At 1220 the STA 115 or the AP 105 may measure a signal strength for a transmission received on the anchor link, or on a second link, or a combination thereof. The operations of 1220 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1220 may be performed by a multi-link manager as described with reference to FIGS. 7 through 10.
At 1225 the STA 115 or the AP 105 may select a wireless link of the plurality of wireless links for communications during the multi-link session based at least in part on the measured signal strength. The operations of 1225 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1225 may be performed by a multi-link manager as described with reference to FIGS. 7 through 10.
FIG. 13 shows a flowchart illustrating a method 1300 for management procedure in multi-channel aggregation in accordance with aspects of the present disclosure. The operations of method 1300 may be implemented by a STA 115 or an AP 105 or its components as described herein. For example, the operations of method 1300 may be performed by a communications manager as described with reference to FIGS. 7 through 10. In some examples, a STA 115 or an AP 105 may execute a set of codes to control the functional elements of the device to perform the functions described below. Additionally or alternatively, the STA 115 or the AP 105 may perform aspects of the functions described below using special-purpose hardware.
At 1305 the STA 115 or the AP 105 may identify an anchor link dedicated to the communication of control and management frames for a multi-link session. The operations of 1305 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1305 may be performed by an anchor link component as described with reference to FIGS. 7 through 10.
At 1310 the STA 115 or the AP 105 may receive a control or management frame from a second wireless device over the identified anchor link. The operations of 1310 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1310 may be performed by a link setup controller as described with reference to FIGS. 7 through 10.
At 1315 the STA 115 or the AP 105 may communicate in parallel between the first wireless device and the second wireless device over plurality of wireless links of the multi-link session based at least in part on the control or management frame. The operations of 1315 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1315 may be performed by a multi-link manager as described with reference to FIGS. 7 through 10.
At 1320 the STA 115 or the AP 105 may transmit one or more frames on a second link during the multi-link session. In some cases, the second link may have a greater bandwidth than the anchor link. The operations of 1320 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1320 may be performed by a multi-link manager as described with reference to FIGS. 7 through 10.
At 1325 the STA 115 or the AP 105 may determine whether the second link is suitable for communications in parallel between the first wireless device and the second wireless device during the multi-link session based at least in part on the one or more frames transmitted on the second link. The operations of 1325 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1325 may be performed by a multi-link manager as described with reference to FIGS. 7 through 10.
FIG. 14 shows a flowchart illustrating a method 1400 for management procedure in multi-channel aggregation in accordance with aspects of the present disclosure. The operations of method 1400 may be implemented by a STA 115 or an AP 105 or its components as described herein. For example, the operations of method 1400 may be performed by a communications manager as described with reference to FIGS. 7 through 10. In some examples, a STA 115 or an AP 105 may execute a set of codes to control the functional elements of the device to perform the functions described below. Additionally or alternatively, the STA 115 or the AP 105 may perform aspects of the functions described below using special-purpose hardware.
At 1405 the STA 115 or the AP 105 may receive an indication of a plurality of links supported by the second wireless device, including an initial anchor link. The operations of 1405 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1405 may be performed by a link setup controller as described with reference to FIGS. 7 through 10.
At 1410 the STA 115 or the AP 105 may identify that the first wireless device does not support the initial anchor link. The operations of 1410 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1410 may be performed by a link setup controller as described with reference to FIGS. 7 through 10.
At 1415 the STA 115 or the AP 105 may identify an anchor link dedicated to the communication of control and management frames for a multi-link session. The operations of 1415 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1415 may be performed by an anchor link component as described with reference to FIGS. 7 through 10.
At 1420 the STA 115 or the AP 105 may transmit, on the anchor link, an indication that the first wireless device does not support the initial anchor link. The operations of 1420 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1420 may be performed by an anchor link component as described with reference to FIGS. 7 through 10.
At 1425 the STA 115 or the AP 105 may receive a control or management frame from a second wireless device over the identified anchor link. The operations of 1425 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1425 may be performed by a link setup controller as described with reference to FIGS. 7 through 10.
At 1430 the STA 115 or the AP 105 may establish the multi-link session between the first wireless device and the second wireless device based at least in part on transmitting the indication that the first wireless device does not support the initial anchor link. The operations of 1430 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1430 may be performed by a multi-link manager as described with reference to FIGS. 7 through 10.
At 1435 the STA 115 or the AP 105 may communicate in parallel between the first wireless device and the second wireless device over plurality of wireless links of the multi-link session based at least in part on the control or management frame. The operations of 1435 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1435 may be performed by a multi-link manager as described with reference to FIGS. 7 through 10.
FIG. 15 shows a flowchart illustrating a method 1500 for management procedure in multi-channel aggregation in accordance with aspects of the present disclosure. The operations of method 1500 may be implemented by a STA 115 or an AP 105 or its components as described herein. For example, the operations of method 1500 may be performed by a communications manager as described with reference to FIGS. 7 through 10. In some examples, a STA 115 or an AP 105 may execute a set of codes to control the functional elements of the device to perform the functions described below. Additionally or alternatively, the STA 115 or the AP 105 may perform aspects of the functions described below using special-purpose hardware.
At 1505 the STA 115 or the AP 105 may identify an anchor link dedicated to the communication of control and management frames for a multi-link session. The operations of 1505 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1505 may be performed by an anchor link component as described with reference to FIGS. 7 through 10.
At 1510 the STA 115 or the AP 105 may transmit a control or management frame over the identified anchor link. The operations of 1510 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1510 may be performed by a link setup controller as described with reference to FIGS. 7 through 10.
At 1515 the STA 115 or the AP 105 may communicate in parallel between the first wireless device and a second wireless device over a plurality of wireless links of the multi-link session based at least in part on the control or management frame. The operations of 1515 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1515 may be performed by a multi-link manager as described with reference to FIGS. 7 through 10.
FIG. 16 shows a flowchart illustrating a method 1600 for management procedure in multi-channel aggregation in accordance with aspects of the present disclosure. The operations of method 1600 may be implemented by a STA 115 or an AP 105 or its components as described herein. For example, the operations of method 1600 may be performed by a communications manager as described with reference to FIGS. 7 through 10. In some examples, a STA 115 or an AP 105 may execute a set of codes to control the functional elements of the device to perform the functions described below. Additionally or alternatively, the STA 115 or the AP 105 may perform aspects of the functions described below using special-purpose hardware.
At 1605 the STA 115 or the AP 105 may transmit an indication of a plurality of links supported by the first wireless device, including an initial anchor link. The operations of 1605 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1605 may be performed by a link setup controller as described with reference to FIGS. 7 through 10.
At 1610 the STA 115 or the AP 105 may receive an indication that the second wireless device does not support the initial anchor link. The operations of 1610 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1610 may be performed by a link setup controller as described with reference to FIGS. 7 through 10.
At 1615 the STA 115 or the AP 105 may identify an anchor link dedicated to the communication of control and management frames for a multi-link session. The operations of 1615 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1615 may be performed by an anchor link component as described with reference to FIGS. 7 through 10.
At 1620 the STA 115 or the AP 105 may transmit a control or management frame over the identified anchor link. The operations of 1620 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1620 may be performed by a link setup controller as described with reference to FIGS. 7 through 10.
At 1625 the STA 115 or the AP 105 may establish the multi-link session between the first wireless device and the second wireless device based at least in part on receiving the indication that the second wireless device does not support the initial anchor link. The operations of 1625 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1625 may be performed by a multi-link manager as described with reference to FIGS. 7 through 10.
At 1630 the STA 115 or the AP 105 may communicate in parallel between the first wireless device and a second wireless device over a plurality of wireless links of the multi-link session based at least in part on the control or management frame. The operations of 1630 may be performed according to the methods described herein. In certain examples, aspects of the operations of 1630 may be performed by a multi-link manager as described with reference to FIGS. 7 through 10.
It should be noted that the methods described above describe possible implementations, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible. Furthermore, aspects from two or more of the methods may be combined.
Techniques described herein may be used for various wireless communications systems such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal frequency division multiple access (OFDMA), single carrier frequency division multiple access (SC-FDMA), and other systems. The terms “system” and “network” are often used interchangeably. A CDMA system may implement a radio technology such as CDMA2000, Universal Terrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000, IS-95, and IS-856 standards. IS-2000 Releases may be commonly referred to as CDMA2000 1×, 1×, etc. IS-856 (TIA-856) is commonly referred to as CDMA2000 1×EV-DO, High Rate Packet Data (HRPD), etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. A TDMA system may implement a radio technology such as Global System for Mobile Communications (GSM). An OFDMA system may implement a radio technology such as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, etc.
The wireless communications system or systems described herein may support synchronous or asynchronous operation. For synchronous operation, the stations may have similar frame timing, and transmissions from different stations may be approximately aligned in time. For asynchronous operation, the stations may have different frame timing, and transmissions from different stations may not be aligned in time. The techniques described herein may be used for either synchronous or asynchronous operations.
The downlink transmissions described herein may also be called forward link transmissions while the uplink transmissions may also be called reverse link transmissions. Each communication link described herein—including, for example, WLANs 100 and 200 of FIGS. 1 and 2—may include one or more carriers, where each carrier may be a signal made up of multiple sub-carriers (e.g., waveform signals of different frequencies).
The description set forth herein, in connection with the appended drawings, describes example configurations and does not represent all the examples that may be implemented or that are within the scope of the claims. The term “exemplary” used herein means “serving as an example, instance, or illustration,” and not “preferred” or “advantageous over other examples.” The detailed description includes specific details for the purpose of providing an understanding of the described techniques. These techniques, however, may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form in order to avoid obscuring the concepts of the described examples.
In the appended figures, similar components or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If just the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label.
Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.
The various illustrative blocks and modules described in connection with the disclosure herein may be implemented or performed with a general-purpose processor, a DSP, an ASIC, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).
The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described above may be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations. Also, as used herein, including in the claims, “or” as used in a list of items (for example, a list of items prefaced by a phrase such as “at least one of” or “one or more of”) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an exemplary step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on.”
Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that can be accessed by a general purpose or special purpose computer. By way of example, and not limitation, non-transitory computer-readable media can comprise RAM, ROM, electrically erasable programmable read only memory (EEPROM), compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to carry or store desired program code means in the form of instructions or data structures and that can be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk and disc, as used herein, include CD, laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.
The description herein is provided to enable a person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein, but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

What is claimed is:

1. An apparatus for wireless communication, comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to:

identify an anchor link dedicated to the communication of control and management frames for a multi-link session;

receive a control or management frame from a wireless device over the identified anchor link; and

communicate in parallel between the apparatus and the wireless device over plurality of wireless links of the multi-link session based at least in part on the control or management frame.

2. The apparatus of claim 1, wherein the instructions are further executable by the processor to cause the apparatus to:

receive, from the wireless device, an indication of the anchor link over the anchor link, or over a second link of the plurality of wireless links different than the anchor link, or a combination thereof.

3. The apparatus of claim 1, wherein the instructions are further executable by the processor to cause the apparatus to:

receive, from the wireless device, an indication of the anchor link in a beacon, or a discovery transmission, or a measurement transmission, or a combination thereof.

4. The apparatus of claim 1, wherein the instructions are further executable by the processor to cause the apparatus to:

transmit, on the identified anchor link, a request to associate with the wireless device.

5. The apparatus of claim 1, wherein the instructions to communicate in parallel between the apparatus and the wireless device over the plurality of wireless links are executable by the processor to cause the apparatus to:

transmit, over the anchor link, data frames and the control and management frames, the anchor link comprising one of the plurality of wireless links; and

transmit data frames over non-anchor links of the plurality of wireless links.

6. The apparatus of claim 1, wherein the instructions are further executable by the processor to cause the apparatus to:

transmit data frames over one or more of the plurality of wireless links; and

receive, over the anchor link, one or more acknowledgements in response to the transmitted data frames.

7. The apparatus of claim 1, wherein the instructions are further executable by the processor to cause the apparatus to:

measure a signal strength for a transmission received on the anchor link, or on a second link, or a combination thereof; and

select a wireless link of the plurality of wireless links for communications during the multi-link session based at least in part on the measured signal strength.

8. The apparatus of claim 1, wherein the instructions are further executable by the processor to cause the apparatus to:

transmit one or more frames on a second link during the multi-link session; and

determine whether the second link is suitable for communications in parallel between the apparatus and the wireless device during the multi-link session based at least in part on the one or more frames transmitted on the second link.

9. The apparatus of claim 1, wherein the instructions are further executable by the processor to cause the apparatus to:

receive an indication of a plurality of links supported by the wireless device, including an initial anchor link;

identify that the apparatus does not support the initial anchor link;

transmit, on the anchor link, an indication that the apparatus does not support the initial anchor link; and

establish the multi-link session between the apparatus and the wireless device based at least in part on transmitting the indication that the apparatus does not support the initial anchor link.

10. The apparatus of claim 1, wherein the instructions to identify the anchor link are executable by the processor to cause the apparatus to:

transmit, to the wireless device, an indication of a preferred anchor link of the apparatus; and

receive, from the wireless device, an indication of the anchor link to be used by the apparatus.

11. The apparatus of claim 1, wherein the instructions to receive the control or management frame from the wireless device are executable by the processor to cause the apparatus to:

receive, on the anchor link, aggregation capability information for the wireless device, the aggregation capability information indicating a capability of the wireless device to communicate in parallel over the plurality of wireless links.

12. The apparatus of claim 11, wherein the aggregation capability information comprises a capability of the wireless device to communicate in parallel over the plurality of wireless links, or current operating parameters of the wireless device, or a combination thereof.

13. The apparatus of claim 11, wherein the instructions to receive the aggregation capability information are executable by the processor to cause the apparatus to:

receive a beacon, or a probe response, or an association response, or a reassociation response, or a combination thereof, that includes the aggregation capability information.

14. The apparatus of claim 1, wherein the instructions are further executable by the processor to cause the apparatus to:

transmit aggregation capability information for the apparatus, the aggregation capability information indicating a capability of the apparatus to communicate in parallel over the plurality of wireless links.

15. The apparatus of claim 14, wherein the instructions to transmit the aggregation capability information are executable by the processor to cause the apparatus to:

transmit a probe request, or an association request, or a reassociation request, or a combination thereof, that includes the aggregation capability information.

16. The apparatus of claim 1, wherein the instructions are further executable by the processor to cause the apparatus to:

receive, from the wireless device, a first operational mode indicator indicating a change in a link aggregation preference for the multi-link session; or

transmit, to the wireless device, a second operational mode indicator indicating the change in the link aggregation preference for the multi-link session.

17. The apparatus of claim 1, wherein the instructions to establish the multi-link session between the apparatus and the wireless device are executable by the processor to cause the apparatus to:

establish a first wireless link of the plurality of wireless links between a first lower media access control (MAC) layer of the apparatus and a first lower MAC layer of the wireless device; and

establish a second wireless link between a second lower MAC layer of the apparatus and a second lower MAC layer of the wireless device, wherein the first lower MAC layer and the second lower MAC layer of the apparatus are in communication with a common upper MAC layer of the apparatus.

18. The apparatus of claim 1, wherein the anchor link comprises a frequency resource, or a time resource, or a spatial stream, or a portion of a packet, or a combination thereof.

19. The apparatus of claim 1, wherein the anchor link uses a first bandwidth and a second link of the plurality of wireless links uses a second bandwidth, the second bandwidth greater than the first bandwidth.

20. The apparatus of claim 1, wherein the instructions are further executable by the processor to cause the apparatus to:

receive, over the anchor link, one or more control or management frames to maintain a second wireless link of the plurality of wireless links, the second wireless link limited such that the second wireless link is unable to be maintained between the apparatus and the wireless device absent the one or more control or management frames received over the anchor link.

21. An apparatus for wireless communication, comprising:

a processor;

memory in electronic communication with the processor; and

transmit a control or management frame over the identified anchor link; and

communicate in parallel between the apparatus and a wireless device over a plurality of wireless links of the multi-link session based at least in part on the control or management frame.

22. The apparatus of claim 21, wherein the instructions are further executable by the processor to cause the apparatus to:

transmit an indication of the anchor link on the anchor link, or on a second link different than the anchor link, or a combination thereof.

23. The apparatus of claim 21, wherein the instructions are further executable by the processor to cause the apparatus to:

transmit an indication of the anchor link in a beacon, or a discovery transmission, or a measurement transmission, or a combination thereof.

24. The apparatus of claim 21, wherein the instructions are further executable by the processor to cause the apparatus to:

transmit an indication of a plurality of links supported by the apparatus, including an initial anchor link;

receive an indication that the wireless device does not support the initial anchor link; and

establish the multi-link session between the apparatus and the wireless device based at least in part on receiving the indication that the wireless device does not support the initial anchor link.

25. The apparatus of claim 21, wherein the instructions are further executable by the processor to cause the apparatus to:

receive, from the wireless device, an indication of a preferred anchor link of the wireless device; and

transmit, to the wireless device, an indication of the anchor link to be used by the wireless device for the association procedure.

26. A method for wireless communication at a first wireless device, comprising:

identifying an anchor link dedicated to the communication of control and management frames for a multi-link session;

receiving a control or management frame from a second wireless device over the identified anchor link; and

communicating in parallel between the first wireless device and the second wireless device over plurality of wireless links of the multi-link session based at least in part on the control or management frame.

27. The method of claim 26, further comprising:

receiving, from the second wireless device, an indication of the anchor link over the anchor link, or over a second link of the plurality of wireless links different than the anchor link, or a combination thereof.

28. The method of claim 26, further comprising:

receiving, from the second wireless device, an indication of the anchor link in a beacon, or a discovery transmission, or a measurement transmission, or a combination thereof.

29. The method of claim 26, further comprising:

transmitting, on the identified anchor link, a request to associate with the second wireless device.

30. A method for wireless communication at a first wireless device, comprising:

transmitting a control or management frame over the identified anchor link; and

communicating in parallel between the first wireless device and a second wireless device over a plurality of wireless links of the multi-link session based at least in part on the control or management frame.