Cloud-based Wi-Fi network system using immediate ACK in uplink data transmission

Patent metadata

Field	Value
Publication number	US-11546101-B2
Application number	US-201916526869-A
Country	US
Kind code	B2
Filing date	Jul 30, 2019
Priority date	Jul 30, 2018
Publication date	Jan 3, 2023
Grant date	Jan 3, 2023

Abstract

A cloud-based Wi-Fi network architecture consisting of a CU and RAUs is proposed as an improvement on the conventional Wi-Fi architecture with traditional access points (APs). In addition, a method for uplink data transmission in a cloud-based Wi-Fi network is proposed. In a conventional Wi-Fi network with independently operating APs, APs close to each other may not be able to utilize the same frequency band efficiently because of significant amounts of interference. However, in a cloud-based Wi-Fi network, the CU coordinates RAUs so that they can operate in the same frequency band by transmitting or receiving signals through the shared wireless medium to improve spectral efficiency. For each frequency band, the proposed system utilizes a diversity combining that combines multiple signals and introduces a single improved signal with high signal-to-noise ratio for uplink transmission in the cloud-based Wi-Fi network. In proposed uplink transmission method for a cloud-based Wi-Fi network, diversity combining is utilized with the immediate acknowledgement (ACK) transmission method that transmits the ACK frame to the client immediately before decoding. The proposed uplink data transmission method mitigates the performance degradation caused by the fronthaul propagation delay between the CU and RAUs, without significant modification of the IEEE 802.11 standard.

First claim

What is claimed is:

1. A cloud-based Wi-Fi network system comprising:
a central unit; and
a plurality of remote access units respectively configured to:
receive a signal comprising a header and data from a client, and
transmit respective report messages, based on information included in the received header, to the central unit,

wherein the central unit is configured to:
select a set of remote access units from the plurality of remote access units to transmit the data from the client to the central unit based on the respective report messages,
perform signal processing, including decoding of the data received from the set of remote access units, and
transmit respective response messages to the set of remote access units before the transmission of the data is completed, including a first response message to a first remote access unit of the set of remote access units designating the first remote access unit as a node to transmit an immediate ACK message to the client,

wherein the first remote access unit is configured to:
transmit the data to the central unit, and
transmit the immediate ACK message to the client in response to receiving the first response message, before decoding of the data is completed.

2. The cloud-based Wi-Fi network system according to claim 1 , wherein the central unit obtains the respective report messages from the plurality of remote access units during a waiting period and selects which of the plurality of remote access units are to transmit the data to the central unit in order for diversity combining based on the respective report messages during a selection period.

3. The cloud-based Wi-Fi network system according to claim 1 , wherein the header of the signal includes at least one of a modulation and coding scheme or data length information.

4. The cloud-based Wi-Fi network system according to claim 1 , wherein the central unit selects which of the plurality of remote access units are to transmit the data based on a signal-to-noise ratio (SNR) level and information included in the header of the signal.

5. The cloud-based Wi-Fi network system according to claim 1 , wherein the central unit selects which of the plurality of remote access unit(s) is/are to transmit the data by calculating a probability of decoding the data received based on a signal-to-noise ratio (SNR) level and information included in the header of the signal.

6. The cloud-based Wi-Fi network system according to claim 1 , wherein the central unit does not select the which of the plurality of remote access units are to transmit the data based on a signal-to-noise ratio (SNR) level being less than the SNR level to decode the data successfully.

7. The cloud-based Wi-Fi network system according to claim 1 , wherein the central unit is connected to the plurality of remote access units by a fronthaul and selects the set of remote access units by increasing a number of remote access units until a fronthaul capacity limitation condition is satisfied.

8. The cloud-based Wi-Fi network system according to claim 1 , wherein the first response message does not designate the first remote access unit as the node to transmit the immediate ACK message to the client based on a signal-to-noise ratio (SNR) level being less than the SNR level to decode the data successfully.

9. The cloud-based Wi-Fi network system according to claim 1 , wherein the central unit performs diversity combining so that the data received from the set of remote access units are combined into a single improved signal.

10. The cloud-based Wi-Fi network system of claim 1 , wherein the central unit is configured to designate the first remote access unit as the node to transmit the immediate ACK message from the first remote access unit, based on a first report message of the respective report messages being indicative of an expected successful decoding of the data at the central unit.

11. The cloud-based Wi-Fi network system of claim 1 , wherein the set of remote access units, including the first remote access unit, is configured to complete transmitting the data to the central unit after the immediate ACK message is sent to the client.

12. The cloud-based Wi-Fi network system of claim 1 , wherein the central unit is configured to abstain from designating the first remote access unit as the node to transmit the immediate ACK message to the client, based on a first report message of the respective report messages being indicative of an expected unsuccessful decoding of the data at the central unit.

Assignees

• Gwangju Inst Science & Tech

Inventors

• Lim Hyuk
• Kim Gyung Min
• Kim Yong Gang

Classifications

• H04L5/0055 Primary

  Physical resource allocation for ACK/NACK (for physical mapping arrangements in ARQ protocols H04L1/1861) · CPC title

• H04W72/29

  between an access point and the access point controlling device · CPC title

• H04W72/541

  using the level of interference · CPC title

• H04W84/12

  WLAN [Wireless Local Area Networks] · CPC title

• H04W88/085

  Access point devices with remote components · CPC title