Multi-Link Operation Assisted 60GHz Beamforming Training And Data Transmission In Wireless Communications

Techniques pertaining to multi-link operation (MLO) assisted 60 GHz beamforming training and data transmission in wireless communications are described. An apparatus (e.g., as a 60 GHz-capable MLO station (STA)) performs MLO assisted 60 GHz operations by: (i) performing discovery and association; and (ii) performing either or both of beamforming training and data transmission in a 60 GHz band.

TECHNICAL FIELD

The present disclosure is generally related to wireless communications and, more particularly, to multi-link operation (MLO) assisted 60 GHz beamforming training and data transmission in wireless communications.

BACKGROUND

Next-generation wireless communication, such as wireless communication in the 60 GHz unlicensed spectrum band as specified in accordance with one or more Institute of Electrical and Electronics Engineers (IEEE) 802.11 specification, tends to provide a large amount of spectrum that enables high data rate in short-range communications. However, the 60 GHz band tends to suffer significant propagation loss and, thus, directional transmissions (or beamforming) are needed. Moreover, discovery, association and beamforming training are complicated procedures in 60 GHz communication systems based on the IEEE 802.11ad and IEEE 802.11ay standards. Therefore, there is a need for a solution of MLO assisted 60 GHz beamforming training and data transmission in wireless communications.

SUMMARY

An objective of the present disclosure is to provide schemes, concepts, designs, techniques, methods and apparatuses pertaining to MLO assisted 60 GHz beamforming training and data transmission in wireless communications. It is believed that aforementioned issue(s) may be avoided or otherwise alleviated by implementation of one or more of various proposed schemes described herein with respect to simplification of discovery, association and beamforming training of 60 GHz communications in MLO assisted 60 GHz systems

In one aspect, a method may involve a processor of an apparatus (e.g., as a 60 GHz-capable MLO station (STA)) performing MLO assisted 60 GHz operations by: (i) performing discovery and association; and (ii) performing either or both of beamforming training and data transmission in a 60 GHz band.

In another aspect, an apparatus may include a transceiver configured to communicate wirelessly and a processor coupled to the transceiver. The processor may perform, via the transceiver, MLO assisted 60 GHz operations by: (i) performing discovery and association; and (ii) performing either or both of beamforming training and data transmission in a 60 GHz band.

It is noteworthy that, although description provided herein may be in the context of certain radio access technologies, networks and network topologies such as, Wi-Fi, the proposed concepts, schemes and any variation(s)/derivative(s) thereof may be implemented in, for and by other types of radio access technologies, networks and network topologies such as, for example and without limitation, Bluetooth, ZigBee, 5th Generation (5G)/New Radio (NR), Long-Term Evolution (LTE), LTE-Advanced, LTE-Advanced Pro, Internet-of-Things (IoT), Industrial IoT (IIoT) and narrowband IoT (NB-IoT). Thus, the scope of the present disclosure is not limited to the examples described herein.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Overview

Implementations in accordance with the present disclosure relate to various techniques, methods, schemes and/or solutions pertaining to MLO assisted 60 GHz beamforming training and data transmission in wireless communications. According to the present disclosure, a number of possible solutions may be implemented separately or jointly. That is, although these possible solutions may be described below separately, two or more of these possible solutions may be implemented in one combination or another.

FIG.1illustrates an example network environment100in which various solutions and schemes in accordance with the present disclosure may be implemented.FIG.2˜FIG.8illustrate examples of implementation of various proposed schemes in network environment100in accordance with the present disclosure. The following description of various proposed schemes is provided with reference toFIG.1˜FIG.8.

Referring toFIG.1, network environment100may involve at least a STA110communicating wirelessly with a STA120. Each of STA110and STA120may be a non-access point (non-AP) STA or, alternatively, either of STA110and STA120may function as an access point (AP) STA. Each of STA110and STA120may be a 60 GHz-capable MLO STA. In some cases, STA110and STA120may be associated with a basic service set (BSS) in accordance with one or more IEEE 802.11 standards (e.g., IEEE 802.11be and future-developed standards). Each of STA110and STA120may be configured to communicate with each other by utilizing the techniques pertaining to MLO assisted 60 GHz beamforming training and data transmission in wireless communications in accordance with various proposed schemes described below, with each of STA110and STA120functioning as an AP, a 60 GHz-capable MLO STA, a beamformer or a beamformee, respectively, in each of the illustrative and non-limiting examples shown inFIG.2˜FIG.6. It is noteworthy that, while the various proposed schemes may be individually or separately described below, in actual implementations some or all of the proposed schemes may be utilized or otherwise implemented jointly. Of course, each of the proposed schemes may be utilized or otherwise implemented individually or separately.

FIG.2illustrates an example scenario200with respect to MLO 60 GHz systems under a proposed scheme in accordance with the present disclosure. In scenario200, an AP and a 60 GHz-capable MLO STA may use one or more sub-7 GHz bands (e.g., 2.4 GHz, 5 GHz and/or 6 GHZ) to associate with each other. As 60 GHz communications may be within a very short range, in scenario200, the AP may not be able to communicate with the STAs in the 60 GHz band. Moreover, as discovery and association of 60 GHz-capable MLO STAs need to be done via one or more sub-7 GHz bands with MLO, each of the 60 GHz-capable MLO STAs needs to report its one or more 60 GHz capabilities to the AP. Under the proposed scheme, the AP may set up a 60 GHz operation period for 60 GHz data transmissions or beamforming training among the group of 60 GHz-capable MLO STAs. Also, each of the 60 GHz-capable MLO STAs may transmit its request(s) of 60 GHz data transmissions or beamforming training to the AP. Accordingly, transmissions and/or beamforming training may be done in the 60 GHz band during the 60 GHz operation period. It is noteworthy that signal exchange over sub-7 GHz bands may or may not be necessary during the 60 GHz operation period.

Referring toFIG.2, an AP and each of 60 GHz-capable MLO STA1 and 60 GHz-capable MLO STA2 may perform discovery and association (e.g., by transmitting and/or receiving control and management signals therebetween) in a sub-7 GHz band (e.g., 2.4 GHz, 5 GHz or 6 GHz). For instance, each of STA1 and STA2 may report or otherwise indicate its one or more 60 GHz capabilities to the AP, and each of STA1 and STA2 may transmit request(s) for 60 GHz data transmission and/or beamforming training to the AP. Accordingly, the AP may set up a 60 GHz operation period during which STA1 and STA2 may perform, in the 60 GHz band, data transmission(s) and/or beamforming training (which may or may not require any signal exchange between STA1 and STA2 over one or more sub-7 GHz bands).

FIG.3illustrates an example scenario300with respect to MLO assisted 60 GHz beamforming training under a proposed scheme in accordance with the present disclosure. Under the proposed scheme, a sub-7 GHz link may be utilized to assist 60 GHz beamforming training, as the sub-7 Ghz link may have a longer range than a 60 GHz link. For instance, a null data packet announcement (NDPA) may be transmitted in a sub-7 GHz band (e.g., 2.4 GHz, 5 GHz or 6 GHz) over the sub-7 GHz link. Moreover, under the proposed scheme, pre-beamformed (e.g., using predefined beambook(s) or sector(s)) null data packets (NDPs) may be transmitted in the 60 GHz band. It is noteworthy that precoded NDPs may need to be applied to enhance the range of 60 GHz beamforming training. Furthermore, under the proposed scheme, the sub-7 GHz link may be utilized to exchange beamforming training results and signaling. For instance, a sector identifier (ID) or beambook ID and/or channel state information (CSI) may be fed back via the sub-7 GHz link.

Referring toFIG.3, between two 60 GHz-capable MLO STAs (e.g., STA1 and STA2), a sub-7 GHz link may be utilized to assist 60 GHz beamforming training. For instance, the sub-7 GHz link may be utilized by STA1 and STA2 to exchange beamforming training results and signaling (e.g., sector ID, beambook ID and/or CSI as feedbacks), while pre-beamformed NDPs (e.g., using predefined beambook(s) or sector(s)) may be transmitted between STA1 and STA2 in the 60 GHz band as part of MLO assisted 60 GHz beamforming training.

FIG.4illustrates an example scenario400with respect to trigger-based MLO assisted 60 GHz beamforming training, which is initiated by a beamformer, under a proposed scheme in accordance with the present disclosure. In scenario400, the MLO assisted 60 GHz beamforming training may be triggered by the beamformer, and thus such beamforming training may be regarded as forward link beamforming training. Under the proposed scheme, an NDPA may be transmitted in a sub 7 GHz band by the beamformer. The interval between sub-7 GHz and 60 GHz transmissions may be herein referred to as a MLO-transmission period (MLO-TP), and the MLO-TP may be much longer than a short inter-frame spacing (SIFS). Under the proposed scheme, a plurality of sequential pre-beamformed (pre-BF) sounding NDPs may be transmitted in the 60 GHz band by the beamformer. The interval between pre-sounding NDPs may be herein referred to as a NDP inter-frame spacing (NIFS), and the NIFS may be much shorter than the SIFS. Under the proposed scheme, pre-BF sounding NDPs may be beamformed with different beamform codewords. For instance, a pre-BF sounding NDP n may be beamformed with an nthcodeword in a predefined beambook. Each codeword in the predefined beambook may be indicated by its index in the beambook. Under the proposed scheme, feedbacks and a beamforming report poll (BFRP) trigger may be transmitted in the sub-7 GHz band by the beamformee. Additionally, the best K beambook indexes and/or the corresponding CSI may be fed back using the sub-7 GHz band. The CSI may be in a compressed format similar to the compressed beamforming feedback as defined in the IEEE 802.11ax/be standards.

FIG.5illustrates an example scenario500with respect to trigger-based MLO assisted 60 GHz beamforming training, which is initiated by a beamformee, under a proposed scheme in accordance with the present disclosure. In scenario500, the MLO assisted 60 GHz beamforming training may be triggered by the beamformee, and thus such beamforming training may be regarded as reversed link beamforming training. Under the proposed scheme, an NDPA may be transmitted in a sub-7 GHz band (e.g., 2.4 GHz, 5 GHz or 6 GHz) by the beamformee. The interval between sub-7 GHz and 60 GHz transmissions may be herein referred to as a MLO-TP, and the MLO-TP may be much longer than a SIFS. Under the proposed scheme, a plurality of sequential pre-BF sounding NDPs may be transmitted in the 60 GHz band by the beamformer. The interval between pre-sounding NDPs may be herein referred to as a NIFS, and the NIFS may be much shorter than the SIFS. Under the proposed scheme, pre-BF sounding NDPs may be beamformed with different beamform codewords. For instance, a pre-BF sounding NDP n may be beamformed with an nthcodeword in a predefined beambook. Each codeword in the predefined beambook may be indicated by its index in the beambook. Under the proposed scheme, feedbacks and a BFRP trigger may be transmitted in the sub-7 GHz band by the beamformee. Additionally, the best K beambook indexes and/or the corresponding CSI may be fed back using the sub-7 GHz band. The CSI may be in a compressed format similar to the compressed beamforming feedback as defined in the IEEE 802.11ax/be standards.

FIG.6illustrates an example scenario600with respect to MLO assisted 60 GHz data transmissions under a proposed scheme in accordance with the present disclosure. Under the proposed scheme, after forward link and reversed link beamforming training, 60 GHz beamforming may be set up between 60 GHz-capable MLO STA pairs. For instance, data transmissions may be performed in the 60 GHz band with a beamformed link between 60 GHz-capable MLO STA pairs. Under the proposed scheme, 60 GHz-capable MLO STAs may use one or more sub-7 GHz bands (e.g., 2.4 GHz, 5 GHz and/or 6 GHz) to coordinate 60 GHz data transmissions. For instance, a 60 GHz transmission period may be set up via a sub-7 GHz link. Moreover, sub-7 GHz link may also be utilized as a part of data transmission using MLO.

Referring toFIG.6, after the forward link and reversed link beamforming training such as those shown inFIG.4andFIG.5, 60 GHz beamforming may be set up between 60 GHz-capable MLO STA1 and 60 GHz-capable MLO STA2. Accordingly, data transmissions may be performed over a 60 GHz link in the 60 GHz band with a beamformed link between STA1 and STA2. Moreover, a sub-7 GHz link may be utilized by STA1 and STA2 to coordinate data transmissions in the 60 GHz band. For instance, a 60 GHz transmission period may be negotiated, coordinated or otherwise set up between STA1 and STA2 by utilizing the sub-7 GHz band. Furthermore, the sub-7 GHz band may also be utilized in data transmissions (along with the 60 GHz link) as part of MLO.

Illustrative Implementations

FIG.7illustrates an example system700having at least an example apparatus710and an example apparatus720in accordance with an implementation of the present disclosure. Each of apparatus710and apparatus720may perform various functions to implement schemes, techniques, processes and methods described herein pertaining to MLO assisted 60 GHz beamforming training and data transmission in wireless communications, including the various schemes described above with respect to various proposed designs, concepts, schemes, systems and methods described above as well as processes described below. For instance, apparatus710may be implemented in STA110and apparatus720may be implemented in STA120, or vice versa.

Each of apparatus710and apparatus720may be a part of an electronic apparatus, which may be a non-AP STA or an AP STA, such as a portable or mobile apparatus, a wearable apparatus, a wireless communication apparatus or a computing apparatus. When implemented in a STA, each of apparatus710and apparatus720may be implemented in a smartphone, a smart watch, a personal digital assistant, a digital camera, or a computing equipment such as a tablet computer, a laptop computer or a notebook computer. Each of apparatus710and apparatus720may also be a part of a machine type apparatus, which may be an IoT apparatus such as an immobile or a stationary apparatus, a home apparatus, a wire communication apparatus or a computing apparatus. For instance, each of apparatus710and apparatus720may be implemented in a smart thermostat, a smart fridge, a smart door lock, a wireless speaker or a home control center. When implemented in or as a network apparatus, apparatus710and/or apparatus720may be implemented in a network node, such as an AP in a WLAN.

In some implementations, each of apparatus710and apparatus720may be implemented in the form of one or more integrated-circuit (IC) chips such as, for example and without limitation, one or more single-core processors, one or more multi-core processors, one or more reduced-instruction set computing (RISC) processors, or one or more complex-instruction-set-computing (CISC) processors. In the various schemes described above, each of apparatus710and apparatus720may be implemented in or as a STA or an AP. Each of apparatus710and apparatus720may include at least some of those components shown inFIG.7such as a processor712and a processor722, respectively, for example. Each of apparatus710and apparatus720may further include one or more other components not pertinent to the proposed scheme of the present disclosure (e.g., internal power supply, display device and/or user interface device), and, thus, such component(s) of apparatus710and apparatus720are neither shown inFIG.7nor described below in the interest of simplicity and brevity.

In some implementations, apparatus710may also include a transceiver716coupled to processor712. Transceiver716may include a transmitter capable of wirelessly transmitting and a receiver capable of wirelessly receiving data. In some implementations, apparatus720may also include a transceiver726coupled to processor722. Transceiver726may include a transmitter capable of wirelessly transmitting and a receiver capable of wirelessly receiving data. It is noteworthy that, although transceiver716and transceiver726are illustrated as being external to and separate from processor712and processor722, respectively, in some implementations, transceiver716may be an integral part of processor712as a system on chip (SoC), and transceiver726may be an integral part of processor722as a SoC.

In some implementations, apparatus710may further include a memory714coupled to processor712and capable of being accessed by processor712and storing data therein. In some implementations, apparatus720may further include a memory724coupled to processor722and capable of being accessed by processor722and storing data therein. Each of memory714and memory724may include a type of random-access memory (RAM) such as dynamic RAM (DRAM), static RAM (SRAM), thyristor RAM (T-RAM) and/or zero-capacitor RAM (Z-RAM). Alternatively, or additionally, each of memory714and memory724may include a type of read-only memory (ROM) such as mask ROM, programmable ROM (PROM), erasable programmable ROM (EPROM) and/or electrically erasable programmable ROM (EEPROM). Alternatively, or additionally, each of memory714and memory724may include a type of non-volatile random-access memory (NVRAM) such as flash memory, solid-state memory, ferroelectric RAM (FeRAM), magnetoresistive RAM (MRAM) and/or phase-change memory.

Each of apparatus710and apparatus720may be a communication entity capable of communicating with each other using various proposed schemes in accordance with the present disclosure. For illustrative purposes and without limitation, a description of capabilities of apparatus710, as STA110, and apparatus720, as STA120, is provided below. It is noteworthy that, although a detailed description of capabilities, functionalities and/or technical features of apparatus720is provided below, the same may be applied to apparatus710although a detailed description thereof is not provided solely in the interest of brevity. It is also noteworthy that, although the example implementations described below are provided in the context of WLAN, the same may be implemented in other types of networks.

Under various proposed schemes pertaining to MLO assisted 60 GHz beamforming training and data transmission in wireless communications in accordance with the present disclosure, with apparatus710implemented in or as STA110and apparatus720implemented in or as STA120in network environment100, processor712of apparatus710may perform, via transceiver716, performing, by a processor of an apparatus, MLO assisted 60 GHz operations. For instance, processor712may perform discovery and association. Moreover, processor712may perform either or both of beamforming training and data transmission in a 60 GHz band.

In some implementations, in performing the discovery and association, processor712may exchange control and management signals with an AP via one or more sub-7 GHz bands. In some implementations, the one or more sub-7 GHz bands may include one or more of a 2.4 GHz band, a 5 GHz band and a 6 GHz band.

In some implementations, in exchanging the control and management signals with the AP, processor712may perform certain operations. For instance, processor712may report one or more 60 GHz capabilities to the AP. Additionally, processor712may transmit one or more requests for either or both of the beamforming training and the data transmission to the AP. In some implementations, in performing either or both of the beamforming training and the data transmission, processor712may perform either or both of the beamforming training and the data transmission during a 60 GHz operation period set up by the AP.

In some implementations, in performing the beamforming training, processor712may perform certain operations. For instance, processor712may transmit one or more pre-beamformed NDPs in the 60 GHz band. Moreover, processor712may exchange beamforming training results and signaling via a sub-7 GHz link. In some implementations, in exchanging the beamforming training results and signaling, processor712may feedback one or more of a sector ID, beambook ID and CSI.

In some implementations, in performing the beamforming training, processor712may perform a forward link beamforming training as a beamformer. For instance, processor712may transmit an NDPA in a sub-7 GHz band. Additionally, processor712may transmit one or more pre-beamformed sounding NDPs in the 60 GHz band. Moreover, processor712may transmit a BFRP trigger in the sub-7 GHz band. Furthermore, processor712may receive either or both of one or more beambook indexes and CSI from a beamformee in the sub-7 GHz band. In some implementations, a first interval between the NDPA transmitted in the sub-7 GHz band and a beginning of the one or more pre-beamformed sounding NDPs transmitted in the 60 GHz may be an MLO-TP. Moreover, a second interval between every two adjacent pre-beamformed sounding NDPs of the one or more pre-beamformed sounding NDPs may be an NIFS. Additionally, a third interval between an end of the one or more pre-beamformed sounding NDPs transmitted in the 60 GHz and the BFRP trigger transmitted in the sub-7 GHz band may be the MLO-TP. Furthermore, a fourth interval between the BFRP trigger and either or both of the one or more beambook indexes and CSI may be a SIFS. In such cases, the MLO-TP may be greater than the SIFS, which may be greater than the NIFS.

In some implementations, in performing the beamforming training, processor712may perform a reversed link beamforming training as a beamformee. For instance, processor712may transmit an NDPA in a sub-7 GHz band. Additionally, processor712may receive one or more pre-beamformed sounding NDPs in the 60 GHz band. Moreover, processor712may transmit either or both of one or more beambook indexes and CSI from a beamformee in the sub-7 GHz band. In some implementations, a first interval between the NDPA transmitted in the sub-7 GHz band and a beginning of the one or more pre-beamformed sounding NDPs received in the 60 GHz may be an MLO-TP. Moreover, a second interval between every two adjacent pre-beamformed sounding NDPs of the one or more pre-beamformed sounding NDPs may be an NIFS. Furthermore, a third interval between an end of the one or more pre-beamformed sounding NDPs received in the 60 GHz and either or both of the one or more beambook indexes and CSI transmitted in the sub-7 GHz band may be the MLO-TP, with the MLO-TP being greater than the NIFS.

In some implementations, in performing the data transmission, processor712may perform the data transmission over a beamformed link in the 60 GHz band after a forward link beamforming training and a reversed link beamforming training. Alternatively, or additionally, in performing the data transmission, processor712may perform the data transmission during a 60 GHz transmission period that is set up by using a sub-7 GHz link. Alternatively, or additionally, in performing the data transmission, processor712may perform the data transmission via a 60 GHz link and the sub-7 GHz link.

Illustrative Processes

FIG.8illustrates an example process800in accordance with an implementation of the present disclosure. Process800may represent an aspect of implementing various proposed designs, concepts, schemes, systems and methods described above. More specifically, process800may represent an aspect of the proposed concepts and schemes pertaining to MLO assisted 60 GHz beamforming training and data transmission in wireless communications in accordance with the present disclosure. Process800may include one or more operations, actions, or functions as illustrated by one or more of blocks810as well as sub-blocks812and814. Although illustrated as discrete blocks, various blocks of process800may be divided into additional blocks, combined into fewer blocks, or eliminated, depending on the desired implementation. Moreover, the blocks/sub-blocks of process800may be executed in the order shown inFIG.8or, alternatively in a different order. Furthermore, one or more of the blocks/sub-blocks of process800may be executed repeatedly or iteratively. Process800may be implemented by or in apparatus710and apparatus720as well as any variations thereof. Solely for illustrative purposes and without limiting the scope, process800is described below in the context of apparatus710implemented in or as STA110functioning as a non-AP STA and apparatus720implemented in or as STA120functioning as an AP STA of a wireless network such as a WLAN in network environment100in accordance with one or more of IEEE 802.11 standards. Process800may begin at block810.

At810, process800may involve processor712of apparatus710performing, via transceiver716, performing, by a processor of an apparatus, MLO assisted 60 GHz operations, which may be represented by812and814.

At814, process800may involve processor712performing either or both of beamforming training and data transmission in a 60 GHz band.

In some implementations, in performing the discovery and association, process800may involve processor712exchanging control and management signals with an AP via one or more sub-7 GHz bands. In some implementations, the one or more sub-7 GHz bands may include one or more of a 2.4 GHz band, a 5 GHz band and a 6 GHz band.

In some implementations, in exchanging the control and management signals with the AP, process800may involve processor712performing certain operations. For instance, process800may involve processor712reporting one or more 60 GHz capabilities to the AP. Additionally, process800may involve processor712transmitting one or more requests for either or both of the beamforming training and the data transmission to the AP. In some implementations, in performing either or both of the beamforming training and the data transmission, process800may involve processor712performing either or both of the beamforming training and the data transmission during a 60 GHz operation period set up by the AP.

In some implementations, in performing the beamforming training, process800may involve processor712performing certain operations. For instance, process800may involve processor712transmitting one or more pre-beamformed NDPs in the 60 GHz band. Moreover, process800may involve processor712exchanging beamforming training results and signaling via a sub-7 GHz link. In some implementations, in exchanging the beamforming training results and signaling, process800may involve processor712feedbacking back one or more of a sector ID, beambook ID and CSI.

In some implementations, in performing the beamforming training, process800may involve processor712performing a forward link beamforming training as a beamformer. For instance, process800may involve processor712transmitting an NDPA in a sub-7 GHz band. Additionally, process800may involve processor712transmitting one or more pre-beamformed sounding NDPs in the 60 GHz band. Moreover, process800may involve processor712transmitting a BFRP trigger in the sub-7 GHz band. Furthermore, process800may involve processor712receiving either or both of one or more beambook indexes and CSI from a beamformee in the sub-7 GHz band. In some implementations, a first interval between the NDPA transmitted in the sub-7 GHz band and a beginning of the one or more pre-beamformed sounding NDPs transmitted in the 60 GHz may be an MLO-TP. Moreover, a second interval between every two adjacent pre-beamformed sounding NDPs of the one or more pre-beamformed sounding NDPs may be an NIFS. Additionally, a third interval between an end of the one or more pre-beamformed sounding NDPs transmitted in the 60 GHz and the BFRP trigger transmitted in the sub-7 GHz band may be the MLO-TP. Furthermore, a fourth interval between the BFRP trigger and either or both of the one or more beambook indexes and CSI may be a SIFS. In such cases, the MLO-TP may be greater than the SIFS, which may be greater than the NIFS.

In some implementations, in performing the beamforming training, process800may involve processor712performing a reversed link beamforming training as a beamformee. For instance, process800may involve processor712transmitting an NDPA in a sub-7 GHz band. Additionally, process800may involve processor712receiving one or more pre-beamformed sounding NDPs in the 60 GHz band. Moreover, process800may involve processor712transmitting either or both of one or more beambook indexes and CSI from a beamformee in the sub-7 GHz band. In some implementations, a first interval between the NDPA transmitted in the sub-7 GHz band and a beginning of the one or more pre-beamformed sounding NDPs received in the 60 GHz may be an MLO-TP. Moreover, a second interval between every two adjacent pre-beamformed sounding NDPs of the one or more pre-beamformed sounding NDPs may be an NIFS. Furthermore, a third interval between an end of the one or more pre-beamformed sounding NDPs received in the 60 GHz and either or both of the one or more beambook indexes and CSI transmitted in the sub-7 GHz band may be the MLO-TP, with the MLO-TP being greater than the NIFS.

In some implementations, in performing the data transmission, process800may involve processor712performing the data transmission over a beamformed link in the 60 GHz band after a forward link beamforming training and a reversed link beamforming training. Alternatively, or additionally, in performing the data transmission, process800may involve processor712performing the data transmission during a 60 GHz transmission period that is set up by using a sub-7 GHz link. Alternatively, or additionally, in performing the data transmission, process800may involve processor712performing the data transmission via a 60 GHz link and the sub-7 GHz link.

Additional Notes