US-12628217-B2 - Method and apparatus for performing block ACK in multiple link of wireless LAN communication system

US12628217B2US 12628217 B2US12628217 B2US 12628217B2US-12628217-B2

Abstract

The present invention relates to a method for operating a first communication node in a wireless local area network (WLAN) supporting a multi-link operation, comprising the steps of: setting a first transmit window size of a first link for transmitting a plurality of frames to a second communication node; transmitting the plurality of frames through the first link; when the state of a channel detected through channel sensing in the second link is an idle state, setting a transmit opportunity (TXOP) in the channel; and when the transmit opportunity is set, performing an agreement with the second communication node on the size of a second transmit window for transmitting the plurality of frames. Therefore, it is possible to improve the performance of a communication system.

Inventors

Sung Hyun Hwang
Kyu Min Kang
Jae cheol Park
Jin Hyung OH
Su Na CHOI
Yong Ho Kim
Yong Su Gwak

Assignees

ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
KOREA NATIONAL UNIVERSITY OF TRANSPORTATION INDUSTRY-ACADEMIC COOPERATION FOUNDATION

Dates

Publication Date: 20260512
Application Date: 20200710
Priority Date: 20190712

Claims (7)

1 . An access point (AP) multi-link device (MLD) in a communication system, comprising: a first AP having a fourth medium access control (MAC) address and operating in a first link of multi-links; a second AP having a fifth MAC address and operating in a second link of the multi-links; a second MAC service access point (SAP) having a MAC-SAP 2 address; and a memory storing one or more instructions for controlling operations of the first AP, the second AP, and the second MAC SAP, wherein the one or more instructions execute to: receive, by the first AP, a block acknowledgement (BA) agreement request from a station (STA) MLD in the first link among the multi-links, wherein the STA MLD includes a first STA having a first MAC address and operating in the first link of the multi-links, a second STA having a second MAC address and operating in the second link of the multi-links, and a first MAC SAP having a MAC-SAP 1 address; transmit, by the first AP, a BA agreement response to the STA MLD in the first link among the multi-links; configure, by the AP MLD, a buffer for the BA agreement; receive, by the first AP, a first data unit from the STA MLD of which a transmitter address (TA) is the first MAC address in the first link among the multi-links; receive, by the second AP, a second data unit from the STA MLD of which a TA is the second MAC address in the second link among the multi-links; and perform, by the AP MLD, a reordering operation for the first data unit and the second data unit which are stored in the buffer, wherein the buffer is configured for <first MAC SAP, TID> tuple, the first and second data units received from the STA MLD are stored in the buffer for the <first MAC SAP, TID> tuple, the reordering operation is applied to the first and second data units stored in the buffer for the <first MAC SAP, TID> tuple, and the BA agreement is not performed between the second AP and the second STA.
2 . The AP MLD according to claim 1 , wherein the one or more instructions further execute to: transmit, by the first AP, a first BA frame in response to the first data unit in the first link; and transmit, by the second AP, a second BA frame in response to the second data unit in the second link, wherein the first BA frame and the second BA frame are transmitted simultaneously.
3 . The AP MLD according to claim 1 , wherein the BA agreement request is an ADDBA request frame including at least one of the MAC-SAP 1 address of the first MAC SAP, the first MAC address of the first STA, or the second MAC address of the second STA from the STA MLD, the first MAC SAP, the first STA, and the second STA being affiliated with the STA MLD, and the BA agreement response is an ADDBA response frame in response to the ADDBA request frame.
4 . The AP MLD according to claim 3 , wherein the MAC-SAP 2 address is a MAC address representing the AP MLD, and the MAC-SAP 1 address is a MAC address representing the STA MLD.
5 . The AP MLD according to claim 1 , wherein each of the fourth MAC address and the fifth MAC address is a lower MAC address of the MAC-SAP 2 address.
6 . The first-AP MLD according to claim 1 , wherein the reordering operation is performed based on a sequence number (SN) of each of the first data unit and the second data unit.
7 . A station (STA) multi-link device (MLD) in a communication system, comprising: a first STA having a first medium access control (MAC) address and operating in a first link of multi-links; a second STA having a second MAC address and operating in a second link of the multi-links; a first MAC service access point (SAP) having a MAC-SAP 1 address; and a memory storing one or more instructions for controlling operations of the first STA, the second STA, and the first MAC SAP, wherein the one or more instructions execute to: transmit, by the first STA, a block acknowledgement (BA) agreement request to an access point (AP) MLD in the first link among the multi-links, wherein the AP MLD includes a first AP having a fourth MAC address and operating in the first link of the multi-links, a second AP having a fifth MAC address and operating in the second link of the multi-links, and a second MAC SAP having a MAC-SAP 2 address; receive, by the first STA, a BA agreement response from the AP MLD in the first link among the multi-links; configure, by the STA MLD, a buffer for the BA agreement for transmission; transmit, to the first AP, a first data unit of which a transmitter address (TA) is the first MAC address in the first link; transmit, to the second AP, a second data unit of which a TA is the second MAC address in the second link among the multi-links; receive, by the STA MLD, a first BA frame from the AP MLD of which a TA is the fourth MAC address in the first link among the multi-links; and receive, by the STA MLD, a second BA frame from the AP MLD of which a TA is the fifth MAC address in the second link among the multi-links; wherein the buffer for transmission is configured for the <second MAC SAP, TID> tuple, based on the first BA frame and the second BA frame, an updating operation is applied for the <second MAC SAP, TID> tuple, and the BA agreement is not performed between the second STA and the second AP.

Description

TECHNICAL FIELD The present invention relates to a method for performing block acknowledgement (ACK) in a wireless LAN communication system, and more specifically, to a method, an apparatus, and a system for performing block acknowledgement in multi-link. BACKGROUND ART With the advancement of the information age, wireless LAN (WLAN) technology is in the spotlight. The wireless LAN technology is a technology that connects two or more devices by applying orthogonal frequency division multiplex (OFDM) technology. This allows users to continuously access a network while moving at any time in a place where a wireless network equipment exists, such as home or office. Most wireless LAN technologies today are based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards and are well known under the marketing name of ‘Wi-Fi’. In particular, since the core technologies of the 4th industrial revolution era, such as artificial intelligence and autonomous driving technology, need to process a large amount of data in real time, the wireless LAN technology, which has a lower operating cost compared to cellular communications, is getting more attention, and many studies are currently being conducted. The wireless LAN technology using a 2.4 GHz frequency band through the IEEE 802.11 started with supporting a speed of 1˜2 megabits per second (Mbps), applying technologies such as frequency hopping, spread spectrum, and infrared communication. Thereafter, while supporting a speed of up to 54 Mbps, various technologies such as quality for service (QoS) improvement, compatibility with an access point (AP) protocol, security enhancement, radio resource measurement, wireless access vehicle environment, fast roaming, mesh network, interworking with external networks, wireless network management, etc. are being put into practice or being developed. Among the current IEEE 802.11 standards, the IEEE 802.11a/b/g/n/ac/ad have been commercialized, and the IEEE 802.11b of them supports a communication speed of up to 11 Mbps while using frequency of the 2.4 GHz band. Since the IEEE 802.11a uses various communication protocols, it uses a 5 GHz band instead of the 2.4 GHz band having severe interferences, and improves the communication speed up to 54 Mbps by applying the OFDM technology. However, according to characteristics of radio waves, radio waves in the 5 GHz band have good straightness, while a diffraction performance is poor. Accordingly, the IEEE 802.11a has a short communication distance compared to the IEEE 802.11b. The IEEE 802.11g uses the 2.4 GHz band like the IEEE 802.11b. It realizes a communication speed of up to 54 Mbps and shows good performance in terms of backward compatibility with the IEEE 802.11b. The IEEE 802.11n is a technology developed to overcome the limitation of communication speed known as a weakness of the wireless LAN. It aims to increase the network speed and reliability and extend the operation distance of the wireless network. By applying multiple-inputs and multiple-outputs (MIMO) technology that uses multiple antennas at both ends of a transmitter and a receiver along with the OFDM technology, the IEEE 802.11n supports a high throughput (HT) with a maximum data processing rate of 540 Mbps or more. In addition, a coding scheme for transmitting multiple duplicate copies was also adopted to increase data reliability. The IEEE 802.11ac was developed to support a higher throughput (i.e., very high throughput (VHT)) than the high throughput (HT) having a maximum data throughput of 540 Mbps or more. Therefore, the IEEE 802.11ac selects the 5 GHz band as a center frequency band, and configures a wide bandwidth (i.e., 80 MHz˜160 MHz) to support the high data throughput. Also, the IEEE 802.11ac has backward compatibility with the existing products by supporting not only the 5 GHz band but also the existing 2.4 GHz band. The IEEE 802.11ac theoretically achieves a minimum speed of 1 Gbps as a wireless LAN speed of multiple terminals, and a maximum single link speed of at least 500 Mbps. These speeds are realized by introducing enhanced wireless interface technologies, such as a wider radio frequency bandwidth (up to 160 MHz), more MIMO spatial streams (up to 8), multi-user MIMO, and high-order modulation (up to 256 QAM). The IEEE 802.11ad can transmit data using a 60 GHz band instead of the existing 2.5 GHz/5 GHz. Since the IEEE 802.11ad uses beamforming technology to support a speed of up to 7 Gbps, it is suitable for a large amount of data or a high bit rate video streaming of an uncompressed HD video. Due to the low diffraction property according to the frequency characteristics, the IEEE801.11ad may be used only in a short distance because the radio waves thereof are difficult to pass through an obstacle. The IEEE 802.11ax aims to increase an average transmission rate per user by at least 4 times or more by supporting functions for implementing high-speed wireless technology in a dense