US 10020919

An analysis of United States Patent 10,020,919 reveals its significance in the field of wireless communications, particularly in the context of Wi-Fi technology. The patent has been the subject of notable litigation.

Patent Summary

• Title: Protection methods for wireless transmissions
• Assignee: The patent was originally assigned to Newracom Inc. and is currently assigned to Atlas Global Technologies LLC.
• Inventors: Dae Won Lee, Young Hoon Kwon, Yujin Noh, Sungho Moon, Ahmad Reza HEDAYAT.
• Filing Date: April 25, 2017
• Issue Date: July 10, 2018
• Abstract: The patent describes methods for protecting wireless transmissions in networks that use Multi-User Multiple-Input-Multiple-Output (MU-MIMO) and Orthogonal Frequency Division Multiple Access (OFDMA) technologies. The disclosed methods involve the use of Multi-User Request-To-Send (MU-RTS) and Clear-To-Send (CTS) frames with specific data scrambling techniques to improve efficiency and avoid interference. It also details procedures for obtaining Channel State Information (CSI) feedback from multiple users, allowing for more reliable and efficient multi-user communications.

Plain-Language Overview of Independent Claims

U.S. Patent 10,020,919 has three independent claims, which are the broadest statements of the invention.

• Independent Claim 1: This claim outlines a method for a wireless device to respond to a "Multi-User Request-To-Send" (MU-RTS) signal. When a device receives an MU-RTS, it descrambles the data in that signal using a specific initial scrambling sequence. It then generates its own "Clear-to-Send" (CTS) response. The key innovation is that the CTS response is scrambled using a second scrambling sequence that is directly derived from and is a cyclic shift of the first scrambling sequence from the MU-RTS. This ensures that when multiple devices reply with CTS frames simultaneously, their signals can be combined in the air without interfering with each other, a process known as RF-combining.

• Independent Claim 10: This claim focuses on a method for a wireless device, such as a Wi-Fi access point, to manage requests for channel quality feedback, known as Channel State Information (CSI), from other devices. The method depends on the number of devices listed in a "Null Data Packet Announcement" (NDPA) frame. If only one device is listed, that device sends its CSI feedback right after receiving a "Null Data Packet" (NDP). If multiple devices are listed, the access point sends an additional "trigger frame" to coordinate their responses, and the devices transmit their CSI feedback simultaneously in a multi-user format. This makes the feedback process more efficient, especially in crowded Wi-Fi environments.

• Independent Claim 15: This claim is the counterpart to claim 10, describing the method from the perspective of the device that initiates the CSI feedback process (e.g., an access point). The device sends out an NDPA and an NDP. If the NDPA was addressed to a single device, it will receive CSI feedback directly. If it was for multiple devices, the access point will first transmit a "trigger frame" to tell the devices how and when to send their feedback, and then it will receive the CSI feedback in a coordinated multi-user transmission. This allows the access point to efficiently gather channel information from several devices at once.

Litigation Information

U.S. Patent 10,020,919 has been asserted in litigation by its current assignee, Atlas Global Technologies LLC. Notably, this patent was part of a lawsuit against TP-Link concerning Wi-Fi 6 technology. In September 2023, a jury in the Eastern District of Texas found that TP-Link had infringed on five of Atlas's patents, including this one, and awarded Atlas $37.5 million in damages.

A search of the U.S. Court of Appeals for the Federal Circuit (CAFC) dockets for 2026 reveals a related case, Atlas Global Technologies LLC v. TP-Link Technologies Co., Ltd., et al., docket number 25-1076, filed on October 21, 2024. This indicates ongoing appellate proceedings related to the district court litigation involving this patent.