Backscatter communication among commodity WiFi radios

US10338205B2 · kind B2 · utility

Assignee

• The Board of Trustees of the Leland Stanford Junior University · US

Inventors

• Pengyu Zhang · Beijing, CN
• Dinesh Bharadia · Stanford, US
• Kiran Joshi · Palo Alto, US
• Sachin Katti · Palo Alto, US

Key dates

• Filing date: Aug 14, 2017
• Grant date: Jul 2, 2019
• Expiry date: Aug 14, 2037

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04B5/77
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A backscatter tag communicate device includes, in part, a receiver configured to receive a WiFi packet conforming to a communication protocol defining a multitude of codewords, a mapper configured to map at least a first subset of the multitude of codewords disposed in the packet to a second multitude of codewords defined by the protocol, and a frequency shifter configured to shift a frequency of the second multitude of codewords such that the frequency shifted codewords are characterized by a single sideband spectrum. The communication protocol may be the 802.11b communication protocol. The mapper may optionally map the first subset of the multitude of codewords by changing phases of the first subset of the multitude of codewords.