The Charles Stark Draper Laboratory, Inc.

Robert D Tingley

Adam J Greenbaum

Bradley A Moran

John M Elwell, Jr

Troy B Jones

Christopher Bessette

Claude P Brancart

Matthew Muresan

Wolf Johnson

In an embodiment, a method includes separating a heterogeneous radio-frequency (RF) signal, received at multiple antennas, into multiple homogenous signals. The multiple antennas have a known positional arrangement. The method further includes estimating a location relative to the known positional arrangement of the antennas of an object producing the RF signal based on phase and amplitude of each homogeneous signal as received at each of the plurality of antennas. The location can further be estimated over multiple time steps, such that velocity and acceleration can be accelerated from the estimated locations.

Autonomous collision avoidance through physical layer tracking

A space-based phased antenna array provides one- or two-dimensional beam steering, yet is compact upon launch and does not require gravity to maintain its shape or orientation. An exemplary antenna array includes a central satellite and at least three peripheral satellites. Each peripheral satellite is mechanically connected to the central satellite by an extendible tether. At launch, the tethers are retracted, so the peripheral satellites are close to, or within, the central satellite. Once in position, the central satellite rotates and extends the tethers, thereby deploying the peripheral satellites in a planar radial pattern. Multiple antenna elements, some disposed on each tether, collectively form a planar phased array that can be electronically beam steered in two dimensions. The antenna array may relay signals, such as between local companion satellites or planet-based stations, and earth. Linear versions, with as few as two tethered satellites, are beam steerable in one dimension.

Space-based tethered communication antenna array

Space-based tethered communications antenna array

In a simultaneous transmit and receive (STAR) communication system, an RF signal splitter couples an antenna to an RF transmitter and to an RF receiver, without using a circulator. An adaptive cancellation RF waveform generator generates an adaptive cancellation RF signal to cancel cross-talk from the RF transmitter to the RF receiver. Training signals are used to characterize signal paths within the STAR system and calculate filter coefficients for generating the adaptive cancellation signal.

Digital simultaneous transmit and receive communication system

A non-GPS satellite-based system enables correction of a local clock in a user device to facilitate GPS-based location determination.

Systems and methods for clock correction

An acoustic telemetry system includes a piezoelectric stack at least partially disposed within a segment of pipe, and electrical circuitry for controlling the piezoelectric stack. In response to a signal from the electrical circuitry, the piezoelectric stack generates a plurality of acoustic signals for transmission through the pipe at different frequencies spanning multiple regions of a frequency response for the pipe.

Methods and systems for communicating data through a pipe

A system and method for determining the location of a transmission source by processing the magnitude of the transmitted signal received at a plurality of receivers with a statistical model of the signal propagation characteristics associated with the signal space between the source and each of the receivers. The system and method also are capable of determining a route of travel between the transmission source and a receiver and/or alternate location.

Low-cost, low-power geolocation system

The invention is directed to a system and method for non-invasive pipeline inspection. According to one embodiment, the system includes a processor, an analyzer, and a wave launcher. The wave launcher is adapted to transmit an input wideband waveform having a selected input energy into the pipeline along a longitudinal axis, and to receive from the pipeline a reflected component of the input waveform having a reflected energy. The analyzer is adapted to generate the input waveform, and to receive the reflected component of the input waveform from the wave launcher. The processor is adapted to compare the input waveform with the reflected component of the input waveform to determine characteristics.

Non-invasive pipeline inspection system

The invention is directed to a system and method for non-invasive pipe inspection. According to one embodiment, the system includes a processor, an analyzer, and a wave launcher. The wave launcher is adapted to transmit an input wideband waveform having a selected input energy into the pipe along a longitudinal axis, and to receive from the pipe a reflected component of the input waveform having a reflected energy. The analyzer is adapted to generate the input waveform, and to receive the reflected component of the input waveform from the wave launcher. The processor is adapted to compare the input waveform with the reflected component of the input waveform to determine characteristics.

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Ashland, MA, United States of America

Robert D Tingley