Abstract:
Systems and methods are described herein for determining the location of a transmitter by jointly and collectively processing the full sampled signal data from a plurality of receivers to form a single solution.
Abstract:
A ranging and tracking system and method employs a Coherent Array Reconciliation Tomography (CART) approach that benefits from a series of samples gathered from deployed receivers in an area of interest, and applies a sequence of matrix operations and transformations to data defining locations in a Cartesian grid space for summing constructive characteristics in a received waveform for identifying a leading edge indicative of a time of arrival (TOA) from a signal source, and computing a metric based on the distance to the signal source. Sampled waveform information (data) from multiple locations in the area of interest allows computation of a likelihood metric for each location in the grid space of containing the signal source. Graphic rendering of the likelihood metric illustrates a position of the signal source by clustering of the locations depicting a high likelihood.
Abstract:
A method for locating a transmitter using a receiver which include, but are not limited to the steps of transmitting a plurality of distinctive and orthogonally polarized signals from a transmitter; receiving the transmitted signals at a pair of separated antennas; demodulating the distinctive orthogonal signals received at each of the pair of separated antennas; and determining a direction to the transmitter from the signals received at the pair of antennas. The system for determining the location of a transmitter using a receiver includes, but is not limited to, having a transmitter adapted for orthogonally transmitting a plurality of distinctive signals; a receiver having a pair of separated antennas for receiving the orthogonally transmitted signals; separate demodulators in the receiver for each antenna of the pair of separated antennas for demodulating the distinctive signals; and signal processing circuitry in the receiver adapted for using the demodulated distinctive signals for determining a direction to the transmitter.
Abstract:
Preferred embodiments of the present invention provide methods of forming a photolithographic pattern by patternwise imaging each of two or more different modalities of light onto a multiphoton-specific photoinitiator material to form a photolithographic pattern on the surface where each of the patterns of the two or more different wavelengths of light overlap. In various embodiments, the invention provides a method of semiconductor fabrication capable of permitting the formation of an imaged feature having a dimension smaller than λ/(2NA), where λ is the smallest wavelength of imaging light, and NA is the numerical aperture of the imaging system.
Abstract:
An indoor localization system uses Visual Simultaneous Localization and Mapping (VSLAM) aided by gyroscope sensor information. Indoor environments pose several challenges which could cause a vision only system to fail due to tracking errors. Investigation revealed significant feature loss in a vision only system when traversing plain walls, windows and staircases. However, the addition of a gyroscope helps in handling such difficult conditions by providing additional rotational information. A portable system consisting of an Inertial Measurement Unit (IMU) and a stereo camera has been developed for indoor mapping. The images and gyroscope rates acquired by the system are stored and post-processed using Gyroscope Assisted Scalable Visual Simultaneous Localization and Mapping Algorithm.
Abstract:
Systems and methods for locating an object are disclosed herein. The locator system includes a plurality of reference units and a processor in communication with the reference units. The reference units are positioned about a region in which a mobile unit is located, and each reference unit includes a transceiver for transmitting and receiving a transaction-based location signal to and from the mobile unit. The processor is configured for estimating time offsets between the mobile unit and reference units and aligning the transaction-based location signals from the reference units by removing the time offsets. The processor is further configured for collectively processing data representative of the aligned location signals based on a plurality of potential locations to identify at least one of the potential locations as a likely mobile unit location.