University of Washington

Jeeva Wireless Inc.

Vamsi Talla

Joshua R Smith

Shyamnath Gollakota

Bryce Kellogg

Aaron N Parks

Vincent Liu

Saman Naderiparizi

Mehrdad Hessar

Vikram Subramaniam Iyer

Ali Najafi

Marco Rolandi

Anthony Weinand

Jonathan Hamberg

Ben Ransford

Mohamad Katanbaf

Hideki Sato

Stephanie Vasko

Michael Brasino

Adnan Kapetanovic

Systems and methods for a full-duplex backscatter system. An example method includes outputting, via a transmitter of the backscatter system, a single tone carrier for transmission via an antenna of the backscatter system. A tunable impedance network is tuned via a microcontroller to reduce self-interference associated with the signal tone carrier by at least a threshold level, with the tunable impedance network including passive elements which are configured to be tuned, and with the self-interference reduction by the threshold level being in the analog domain. Backscatter data packets are received via a receiver from backscatter tags, with the backscatter data packets being associated with an offset frequency and are decoded by the receiver.

Duplex long range backscatter wireless communication systems and methods

Examples described herein include systems, devices, and methods for backscattering carrier signals in accordance with pixel values of an image and/or video. Signals having a property proportionate to pixel values may be converted into a pulse-containing waveform having pulses whose widths and/or duty cycles are determined based on the pixel values. Backscatter transmitters may backscatter a carrier signal in accordance with the pulse-containing waveform to provide the pixel values to a receiver. In this manner, video transmission at low power and/or battery-free operation may be provided.

Image and/or video transmission using backscatter devices

Examples described herein include devices and systems utilizing backscatter communication to generate transmissions in accordance with wireless communication protocols. Examples are described including single sideband operation, generation of a carrier wave using Bluetooth, downlink communication to a backscatter device, and combinations thereof.

Backscatter devices including examples of single sideband operation

Examples described herein include devices and systems utilizing backscatter communication to directly generate transmissions in accordance with wireless communication protocols that can be decoded existing devices. Examples include devices that generate 802.11b transmissions using backscatter communication. Examples of network stacks are described which may facilitate backscatter devices to coexist with other devices (e.g. in the ISM band), without incurring, or reducing a need for, the power consumption or carrier sense and medium access control operations.

Backscatter devices and network systems incorporating backscatter devices

Examples of backscatter systems, device, and techniques are described herein. Example backscatter devices may utilize CSS modulation to provide backscatter signals including CSS signals (e.g., LoRa packets). Utilizing CSS modulation may advantageously allow for backscatter communication over wide areas. Examples of backscatter devices described herein may toggle the impedance of the backscatter device between multiple (e.g., eight) impedances to reduce and/or eliminate higher order harmonic components in the backscatter signal (e.g., third and fifth harmonic components).

Backscatter systems, devices, and techniques utilizing CSS modulation and/or higher order harmonic cancellation

Examples described herein include backscatter devices which may transmit orthogonal frequency division multiplexing (OFDM) signals. Techniques for complex analog backscatter are described. Examples of impedance circuitry are described which may be used to provide real and imaginary components of impedance in accordance with inphase and quadrature bits.

Backscatter devices and systems providing backscattered signals including OFDM packets

Apparatuses, systems, ambient backscatter transceivers, and methods for modulating a backscatter of an ambient RF signal are described. An example system may include an ambient backscatter transceiver comprising an antenna that is configured to receive a backscattered ambient radio frequency (RF) signal. The ambient backscatter transceiver is configured to demodulate the backscattered ambient RF signal to retrieve first data. The backscattered ambient RF signal is generated by backscattering an ambient RF signal at a first frequency. The ambient RF signal is encoded with modulated to provide second data at a second frequency.

Ambient backscatter transceivers, apparatuses, systems, and methods for communicating using backscatter of ambient RF signals

Examples described herein include wireless transmitters configured for power transmission. Example wireless transmitters may insert power packets into wireless communications such that power harvesting circuitry may harvest sufficiently continuous power from the wireless communication signals. Example power harvesting circuitry is configured to harvest power across multiple wireless communication channels. Example chargers are described which may harvest power from wireless communication signals (e.g. Wi-Fi signals).

Power transmission using wireless communication signals

Ambient backscatter tranceivers, apparatuses, systems, and methods for communicating using backscatter of ambient RF signals

Methods for forming inorganic nanostructures are provided. The methods create the inorganic nanostructures by positioning a writing electrode (e.g., a conductive 'stamp') spaced nanometers above a substrate such that a precursor is intermediate the two. Applying an electric field, a voltage bias, an ionic current, or an electronic current between the writing electrode and the substrate converts the precursor into an inorganic solid material (e.g., a semiconductor such as silicon or germanium) in the area of the writing electrode.

Growing community of inventors

Seattle, WA, United States of America

Vamsi Talla