Patents Assigned to SPATIAL DIGITAL SYSTEMS
  • Patent number: 10574338
    Abstract: A system comprises a ground hub and a mobile airborne platform hovering over or close to a coverage area on or near the earth surface. A bistatic radar receiver on the airborne platform includes a first antenna system to capture reflected radiofrequency signals originated from a satellite via reflected paths from the coverage area; and a second antenna system to transmit the reflected radiofrequency signals to the ground hub via a feeder link. At the ground hub, a multibeam antenna system receives the reflected radiofrequency signals and captures radiation signals directly from the satellite via a direct path; and a remote beam forming network remotely forms receiving beams for the first antenna system. A remote radar processing center includes a cross-correlator to receive the reflected radiofrequency signals and the radiation signals as two input signal streams, perform cross-correlations between the two input signal streams, and output an output signal stream.
    Type: Grant
    Filed: April 30, 2019
    Date of Patent: February 25, 2020
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C. D. Chang
  • Patent number: 10560183
    Abstract: A communication system includes (1) a first airborne linear array configured to project a first fan beam over a first ground coverage elongated in a first direction, the first fan beam delivering a first information data associated with a first data stream; and (2) a second airborne linear array configured to project a second fan beam over a second ground coverage elongated in a second direction, the second fan beam delivering a second information data associated with a second data stream. The first and second ground coverages are overlapped to form a common coverage area. The first and second data streams are complementary to each other and are linear combinations of a plurality of segmented substreams. The plurality of segmented substreams is formed from an information data stream. The first and second data streams are generated from a ground control facility.
    Type: Grant
    Filed: June 26, 2018
    Date of Patent: February 11, 2020
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C. D. Chang, Juo-Yu Lee
  • Patent number: 10516872
    Abstract: An apparatus includes a memory storing a digital envelope and a wavefront demultiplexing (WFD) device which receives M input streams concurrently, M being an integer greater than 1, performs a WFD transformation on the M input streams, and generates M output streams concurrently. A first input stream includes wavefront multiplexed digital identifiers for digital right management. A second input stream is the digital envelope. The first input stream presented in a digital format appears to human perception as having identical features to the digital envelope presented in the digital format. Each output stream is a linear combination of the M input streams such that the digital identifiers are recovered from at least one of the M output streams. The digital envelope is a data file used by a sender to send the M input streams and is scaled with a magnification factor greater than 1 in the WFD transformation.
    Type: Grant
    Filed: May 13, 2019
    Date of Patent: December 24, 2019
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C. D. Chang, Juo-Yu Lee, Jeffrey C. Chang, Steve K. Chen
  • Patent number: 10498818
    Abstract: For data writing, a first wavefront multiplexing (WFM) processor performs WFM on M input streams to generate N output streams. A pre-processor segments or codes a source stream to produce the M input streams. For data reading, a first wavefront demultiplexing (WFD) processor performs WFD on M input streams to generate N output streams. A post-processor de-segments or decodes the N output streams into a source stream.
    Type: Grant
    Filed: March 22, 2017
    Date of Patent: December 3, 2019
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C. D. Chang, Juo-Yu Lee, Tzer-Hso Lin
  • Publication number: 20190363784
    Abstract: A communications system includes a ground hub, mobile airborne platforms, and a user terminal. The ground hub includes an antenna system, a beam-forming system and a baseband processor. The antenna system receives return-link signals radiated respectively by the mobile airborne platforms. The return-link signals correspond to signal streams transmitted by the user terminal and received by the mobile airborne platforms. The signal streams correspond to data streams including a known pilot code stream. The beam-forming system forms beams to receive the return-link signals and transforms the received return-link signals into baseband signals. The baseband processor includes adaptive equalizers to equalize the baseband signals and a wavefront demultiplexing processor to perform a wavefront demultiplexing transform on the equalized baseband signals to produce recovered versions of the data streams.
    Type: Application
    Filed: July 22, 2019
    Publication date: November 28, 2019
    Applicant: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C.D. Chang
  • Patent number: 10490892
    Abstract: This device combines multiple elements that function like a single smart antenna that performs both connectivity and spatial discrimination functions. The antenna functions in both receive and transmit modes. The apparatus utilizes commonly used components to distinguish and separate desired satellite signals from those signals of satellites in close directional proximity. Disclosed are six methods for optimizing simultaneously reception of multiple desired satellite signals performed either mechanically or electronically and also included is an optimization technique. The transmission apparatus uses many of the same components as the receiver antenna and additionally uses in-beam nulling to fine tune transmission.
    Type: Grant
    Filed: February 16, 2011
    Date of Patent: November 26, 2019
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C. D. Chang
  • Patent number: 10491325
    Abstract: For signal transmission, a pre-processing device performs a wavefront multiplexing (WVM) transform on M input streams corresponding to M orthogonal beams to generate N output streams using a weight matrix having M beam weight vectors (BWVs) associated with the M orthogonal beams. An antenna array having N elements transmits the N output streams to a plurality of receivers. For signal reception, an antenna array having N elements receives N input streams from a plurality of transmitters. A post-processing device performs a wavefront de-multiplexing (WVD) transform on the N input streams corresponding to M orthogonal beams to generate M output streams using a weight matrix having M beam weight vectors (BWVs) associated with the M orthogonal beams. M and N are positive integers and 1<M?N. The M BWVs are calculated using an optimization procedure based on performance constraints.
    Type: Grant
    Filed: March 22, 2018
    Date of Patent: November 26, 2019
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C. D. Chang, Juo-Yu Lee, Tzer-Hso Lin
  • Publication number: 20190356048
    Abstract: An antenna system includes N movable antenna elements configured to generate concurrently M receiving beams pointing respectively at M satellites radiating in a common frequency band, N and M being integers and N?M?2. A beam forming system is coupled to the N movable antenna elements and configured to shape the M receiving beams using weights inputted from a beam controller. The beam controller optimizes the M receiving beams by computing spatial displacements to spatially reposition the N movable antenna elements relative to each other, using an iterative optimization processing to satisfy a plurality of constraints concurrently. A position driver system spatially re-positions the N movable antenna elements in accordance to the spatial displacements inputted from the beam controller.
    Type: Application
    Filed: July 29, 2019
    Publication date: November 21, 2019
    Applicant: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C.D. Chang, Tzer-Hso Lin, Eric Hu
  • Patent number: 10484081
    Abstract: A receiving terminal for communication via NGSO satellites comprises an outdoor unit coupled to an indoor unit via optical fibers. The outdoor unit comprises an array antenna for capturing signals from the satellites; low-noise amplifiers; analog-to-digital conversion blocks for converting the captured signals to digital signals; a pre-processor for performing a wavefront multiplexing transform on the digital signals and generating wavefront multiplexed signals; and RF-to-optical drivers for transforming the wavefront multiplexed signals to optical waveforms.
    Type: Grant
    Filed: January 9, 2018
    Date of Patent: November 19, 2019
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C. D. Chang, Juo-Yu Lee, Steve K. Chen
  • Publication number: 20190312847
    Abstract: A communications system between a source and a destination includes a transmitter at the source and a communication connectivity. The transmitter comprises a preprocessor and a candidate envelope folder to provide M known a priori digital envelopes, M?1. The preprocessor has N input ports and N output ports, N>M, performs at least one wavefront multiplexing (WFM) transform on N inputs received at the N input ports to generate N outputs at the N output ports. The preprocessor performs the at least one WFM transform by calculating, for each of the N outputs, a linear combination of the N inputs using one of the M digital envelopes such that a digital format of one of the N outputs appears to human sensors as having features substantially identical to a digital format of the one of the M digital envelopes.
    Type: Application
    Filed: June 24, 2019
    Publication date: October 10, 2019
    Applicant: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C.D. Chang, Juo-Yu Lee, Steve K. Chen
  • Publication number: 20190266340
    Abstract: An apparatus includes a memory storing a digital envelope and a wavefront demultiplexing (WFD) device which receives M input streams concurrently, M being an integer greater than 1, performs a WFD transformation on the M input streams, and generates M output streams concurrently. A first input stream includes wavefront multiplexed digital identifiers for digital right management. A second input stream is the digital envelope. The first input stream presented in a digital format appears to human perception as having identical features to the digital envelope presented in the digital format. Each output stream is a linear combination of the M input streams such that the digital identifiers are recovered from at least one of the M output streams. The digital envelope is a data file used by a sender to send the M input streams and is scaled with a magnification factor greater than 1 in the WFD transformation.
    Type: Application
    Filed: May 13, 2019
    Publication date: August 29, 2019
    Applicant: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C.D. Chang, Juo-Yu Lee, Jeffrey C. Chang, Steve K. Chen
  • Patent number: 10367262
    Abstract: An antenna system comprises: multiple antenna elements; and multiple beam forming networks configured to produce radiation patterns for both receiving and transmission functions configured to be optimized by re-positioning said antenna elements, wherein said beam forming networks comprise a receiving beam forming network configured to combine multiple first inputs from said antenna elements into at least a first output, and a transmission beam forming network configured to divide a second input into multiple second outputs to said antenna elements.
    Type: Grant
    Filed: May 20, 2016
    Date of Patent: July 30, 2019
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C. D. Chang, Tzer-Hso Lin, Eric Hu
  • Patent number: 10361775
    Abstract: A retro-directive antenna system on a mobile airborne platform for communication with a ground hub located within a coverage area. The system comprises an antenna array, a receive beamforming network, and a diagnostic processor. The antenna array comprises a plurality of antenna elements. The receive beamforming network generates concurrently a plurality of receive beams for the respective antenna elements. The receive beams correspond to respective beam positions within the coverage area. A first beam position points to the ground hub and a corresponding receive beam receives a target signal from the ground hub. The diagnostic processor determines a best position for the first beam position based on a ranking system and controls the receive beamforming network by updating the beam positions based on the best position for the first beam position.
    Type: Grant
    Filed: March 13, 2017
    Date of Patent: July 23, 2019
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C. D. Chang
  • Patent number: 10333900
    Abstract: Enveloping techniques using incoherent wavefront multiplexing (WF muxing or K-muxing) will enhance privacy protection on data communications. The disclosure relates to methods and architectures of packing or enveloping data using WF muxing, or K-muxing, for information transport via multiple communication links such as concurrently via multiple satellites, airborne platforms, wireless terrestrial links, and/or other wireless links. The multi-link communications may include the use of cloud transport of multiple WF-muxed data packages. It is focused to appearance of a digital envelop and reliability of enclosed data. The K-muxing on information digital streams before modulation in a transmitter shall provide enhanced data privacy and better availability. The WF multiplexed (WF muxed or K-muxed) information data streams will be individually and concurrently sent to the multiple links accordingly for data transport.
    Type: Grant
    Filed: January 12, 2016
    Date of Patent: June 25, 2019
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C. D. Chang, Juo-Yu Lee, Steve K. Chen
  • Patent number: 10320994
    Abstract: Data files with digital envelops may be used for many new applications for cloud computing. The new applications include games and entertainments such as digital fortune cookies, and treasure hunting, unique techniques for digital right management, or even additional privacy and survivability on data storage and transport on cloud computing. Wavefront multiplexing/demultiplexing process (WF muxing/demuxing) embodying an architecture that utilizes multi-dimensional waveforms has found applications in data storage and transport on cloud. Multiple data sets are preprocessed by WF muxing before stored/transported. WF muxed data is aggregated data from multiple data sets that have been “customized processed” and disassembled into any scalable number of sets of processed data, with each set being stored on a storage site. The original data is reassembled via WF demuxing after retrieving a lesser but scalable number of WF muxed data sets.
    Type: Grant
    Filed: October 13, 2014
    Date of Patent: June 11, 2019
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C. D. Chang, Juo-Yu Lee
  • Patent number: 10289856
    Abstract: Multiple data sets are preprocessed by WF muxing before stored/transported. WF muxed data is aggregated data from multiple data sets. The original data is reassembled via WF demuxing after retrieving a lesser but scalable number of WF muxed data sets. A customized set of WF muxing on multiple digital files as inputs including at least a data message file and a selected digital envelop file, is configured to guarantee at least one of the multiple outputs comprising a weighted sum of all inputs with an appearance to human natural sensors substantially identical to the appearance of the selected digital envelop in a same image, video or audio format. The output file is the file with enveloped or embedded messages. The embedded message may be reconstituted by a corresponding WF demuxing processor at destination with the known a priori information of the original digital envelope.
    Type: Grant
    Filed: October 17, 2014
    Date of Patent: May 14, 2019
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C. D. Chang, Juo-Yu Lee, Jeffrey C. Chang, Steve K Chen
  • Patent number: 10277306
    Abstract: A system includes a ground hub and a mobile airborne platform hovering over or close to a coverage area on or near the earth surface. The mobile airborne platform comprises a bistatic radar receiver including an antenna system to capture first radiofrequency signals originated from a first satellite and second radiofrequency signals originated from a second satellite, via direct paths and via reflected paths from the coverage area. The mobile airborne platform transmits the captured first and second radiofrequency signals to a ground hub via a feeder link. The ground hub includes a remote beam forming network to remotely form receiving beams for the antenna system of the bistatic radar receiver to capture the first and second radiofrequency signals, and a remote radar processing center to transform the captured first and second radiofrequency signals into a first and a second two-dimensional radiofrequency image, respectively.
    Type: Grant
    Filed: October 17, 2017
    Date of Patent: April 30, 2019
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C. D. Chang
  • Patent number: 10264052
    Abstract: A system comprises a plurality of personal devices identified by at least one remote storage network as belonging to a user. A personal device comprises a first folder for storing a known a priori digital file, a second folder for storing a data file, a processor, and a network interface. The processor performs an M-to-M waveform multiplexing transformation on M input files, M>1, and generates M output files. Each output file comprises a respective linear combination of the M input files. The M input files comprise the data file and the known a priori digital file. Each of the M output files appears to human perception as having substantially identical visual or audio features to the known a priori digital file. The network interface sends at least M?1 of the M output files to at least one destination in the at least one remote storage network for storage.
    Type: Grant
    Filed: April 14, 2015
    Date of Patent: April 16, 2019
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C. D. Chang, Juo-Yu Lee, Steve K Chen, Jeffrey Chijieh Chang
  • Publication number: 20190108178
    Abstract: An apparatus includes N audio receivers positioned in a pre-defined geometry with respect to P audio sources to receive P audio signals from the P audio sources; N data sets coupled to the N audio receivers to sample the received P audio signals into N data streams; a plurality of storage devices coupled to the N data sets to store the N data streams; and a post processor coupled to the plurality of storage devices to generate output signals corresponding to reconstituted P audio signals using a wavefront demultiplexing transformation, wherein N and P are positive integers and N?P. The post processor has inputs receiving data retrieved from the plurality of storage devices and outputs providing the output signals.
    Type: Application
    Filed: December 11, 2018
    Publication date: April 11, 2019
    Applicant: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C.D. Chang, Juo-Yu Lee, Steve K Chen
  • Patent number: 10256899
    Abstract: A power amplification system comprises a pre-processor including a wavefront multiplexer, a set of power amplifiers, and a post-processor including a wavefront demultiplexer. The wavefront multiplexer receives concurrently N input signals, N being an integer greater than 2, performs a wavefront multiplexing transform on the N input signals by attaching N wavefronts to the N input signals respectively, and generates N first output signals. The N wavefronts are unique and mutually orthogonal. The wavefront multiplexing transform has an inverse. The N power amplifiers amplify the N first output signals and generate N amplified signals. The wavefront demultiplexer performs the inverse of the wavefront multiplexing transform on the N amplified signals and generates N second output signals, the N second output signals corresponding respectively to the N input signals. Each of the N second output signals is an amplified version of a corresponding one of the N input signals.
    Type: Grant
    Filed: September 11, 2017
    Date of Patent: April 9, 2019
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C. D. Chang