Patents by Inventor Donald C. D. Chang

Donald C. D. Chang has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10120873
    Abstract: Presented is a multi-channel data process to utilize wavefront multiplexing for data storage and data stream transport with redundancy on cloud or in a distribution network. This processing features additional applications for multi-media recording and data communications via transponding platforms including satellites, unmanned air vehicles (UAVs), or others for better survivability and faster accessing. Multiple concurrent data streams are pre-processed by a wavefront multiplexer into multiple sub-channels or wavefront components, where signals from respective data streams are replicated into sub-channels. These replicated data streams are linked via a unique complex weighting vector (amplitude and phase or their equivalents), or “wave-front”, which are also linked by various spatially independent wavefronts. Additionally, probing data streams are embedded and linked via some of the independent wavefronts. Aggregated data streams in sub-channels are unique linear combinations of all input data streams.
    Type: Grant
    Filed: May 14, 2015
    Date of Patent: November 6, 2018
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Juo-Yu Lee, Donald C.D. Chang, Steve K. Chen
  • Patent number: 10116409
    Abstract: A novel terrestrial wireless communications technique for terrestrial portable terminals including hand-held mobile devices and fixed wireless instruments, utilizing a spoke-and-hub communications system, having a plurality of individual hubs and/or base-stations all in communications with the portable terminals. The portable terminals and the hubs are assigned to use incompatible polarity formats in terms of circularly polarity (CP) and linearly polarity (LP). In forward links, a signal processed by the LP ground telecommunications hubs is radiated through multiple antennas with various LP polarities to an individual CP user simultaneously. The multiple paths are organized via assignments of a plurality of polarities, frequency slots, and directions by wavefront multiplexing/demultiplexing techniques such that the same communications assets including frequency spectrum may be re-used by other users. The same polarity diversity methods can be extended to peer-to-peer communications.
    Type: Grant
    Filed: June 1, 2015
    Date of Patent: October 30, 2018
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C. D. Chang
  • Patent number: 10116316
    Abstract: A receiver with orthogonal beam forming technique is achieved that is capable of differentiating different signal components within the received composite signal. An adaptive processor is used to eliminate the signal component whose phase information is known or can be calculated. The phase information of the major component of a signal can be easily acquired by using a limiter. The phase information of other signal components can be acquired by their direction information and other characteristics, such as modulation scheme, etc. Multiple orthogonal beams can be formed by eliminating one unwanted signal component each time by the adaptive processor until all unwanted signal is eliminated. Thus, a composite signal from multiple sources can be broken down into their component signals.
    Type: Grant
    Filed: January 28, 2016
    Date of Patent: October 30, 2018
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C. D. Chang, Frank Lu, Yulan Sun
  • Publication number: 20180302150
    Abstract: An apparatus includes a demultiplexing device, a bank of filters, a wavefront processor, and an optimizer. The demultiplexing device demultiplexes M data streams into N wavefront signals which include P pilot signals, N, M, and P being positive integers and N>M. The bank of filters filters the N wavefront signals using filter weights. The wavefront processor, having N input ports and N output ports, performs an N-to-N wavefront demultiplexing transform on the N wavefront signals at the N input ports and outputs N wavefront demultiplexed signals at the N output ports such that each of the N wavefront demultiplexed signals is a linear combination of the N wavefront signals. The N wavefront demultiplexed signals include P recovered pilot signals. The optimizer updates the filter weights using performance indices based on the P recovered pilot signals and known pilot signals corresponding to the P pilot signals.
    Type: Application
    Filed: June 19, 2018
    Publication date: October 18, 2018
    Applicant: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C.D. Chang
  • Publication number: 20180292539
    Abstract: A system for generating and injecting acoustic interference signals to mitigate undesired acoustic noise over a target zone. M pickup sensors pick up acoustic noise signals from one or more noise sources in real time and generate M noise signals, M>1. A beam forming network includes M acoustic beam forming modules to process the M noise signals respectively and generate N acoustic interference signals. N acoustic injectors condition, amplify and inject the N acoustic interference signals over the target zone, N>1. Each of the M acoustic beam forming modules includes a 1-to-N distribution network to transform a respective one of the M noise signals into N signals, and N finite-impulse-response filters to perform amplitude and phase weighting on the respective N signals and generate N intermediate signals which are combined respectively with corresponding intermediate signals generated by remaining M?1 acoustic beam forming modules to generate the N acoustic interference signals.
    Type: Application
    Filed: June 12, 2018
    Publication date: October 11, 2018
    Applicant: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C. D. Chang, Steve K. Chen
  • Patent number: 10090958
    Abstract: A system is provided for high speed optical fiber data transmission by generating artificial wavefronts along multiple paths exhibiting spatial mutual orthogonality. Multiple independent signal streams are “structured” over a group of different propagation paths that are coherently organized by wavefront multiplexing and dc-multiplexing techniques. Therefore, signal streams with enhanced throughput and reliability may be fully recovered at destinations via embedded diagnostic signals and optimization loops. Multiple optical channels are matched with multiple orthogonal wavefronts created by a signal pre-processor. A receiving end signal post-processor dynamically aligns propagation paths via diagnostic signals and orthogonality of the propagation wavefronts electronically. The multiple optical channels are coherently bonded into a single virtual channel, thereby increasing data bandwidth while reducing interference and unwanted multi-path effects.
    Type: Grant
    Filed: July 6, 2015
    Date of Patent: October 2, 2018
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C. D. Chang
  • Patent number: 10090891
    Abstract: Presented are MIMO communications architectures among terminals with enhanced capability of frequency reuse by strategically placing active scattering platforms at right places. These architectures will not depend on multipaths passively from geometry of propagation channels and relative positions of transmitters and those of receivers. For advanced communications which demand high utility efficiency of frequency spectrum, multipath effects are purposely deployed through inexpensive active scattering objects between transmitters and receivers enable a same frequency slot be utilized many folds such as 10×, 100× or even more. These active scatters are to generate favorable geometries of multiple paths for frequency reuse through MIMO techniques. These scatters may be man-made active repeaters, which can be implemented as small as 5 to 10 watt lightbulbs for indoor mobile communications such as in large indoor shopping malls.
    Type: Grant
    Filed: June 8, 2015
    Date of Patent: October 2, 2018
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C. D. Chang, Juo-Yu Lee
  • Patent number: 10084528
    Abstract: A communications system comprises a ground hub in a background area, aerial vehicles flying in a formation with slowly varying spacing between the aerial vehicles, and a user terminal in a region within a foreground area. The foreground area is spatially separate from the background area. The ground hub comprises a ground-based beam forming facility (GBBF) for receiving and transforming input signals into beam-formed signals, and a first antenna system coupled to the GBBF for transmitting concurrently the beam-formed signals in a first frequency band to respective aerial vehicles via respective background links. The aerial vehicles receive respectively the beam-formed signals via the background links and transmit respectively the beam-formed signals as respective signal beams covering at least the region within the foreground area in a second frequency band. The user terminal comprises a second antenna system for receiving concurrently the signal beams via foreground links to the aerial vehicles.
    Type: Grant
    Filed: March 27, 2017
    Date of Patent: September 25, 2018
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C. D. Chang
  • Patent number: 10079886
    Abstract: Presented are cloud storage architectures for private data among terminals with enhanced capability of data privacy and survivability. Pre-processing for storing data in IP cloud comprises: transforming multiple first data sets into multiple second data sets at an uploading site, wherein one of said second data sets comprises a weighted sum of said first data sets; storing said second data sets in an IP cloud via IP connectivity; and storing multiple data storages linking to said second data sets at said uploading site. In accordance with an embodiment post processing may comprise recovering said second data sets at a downloading site via IP network.
    Type: Grant
    Filed: November 6, 2015
    Date of Patent: September 18, 2018
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C. D. Chang, Juo-Yu Lee, Steve K. Chen
  • Patent number: 10069553
    Abstract: A communication system includes a transmitter, one or more active scattering platforms, and one or more remote receivers. The transmitter includes a beam forming network for transforming M signals into a set of shaped beams which are radiated toward the active scattering platforms by transmitter antenna elements. The active scattering platforms receive and re-radiate one or more of the radiated shaped beams toward the receivers. The beam forming network optimizes composite transfer functions under performance constraints. Each composite transfer function is a linear combination of transfer functions. Each transfer function characterizes propagation paths from one transmitter antenna element to one receiving antenna element. Each receiving antenna element is identified by a user element identification index in the transfer functions. Each receiver is identified by a user identification index.
    Type: Grant
    Filed: October 3, 2017
    Date of Patent: September 4, 2018
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C. D. Chang, Juo-Yu Lee
  • Publication number: 20180226982
    Abstract: A broadband linear processing system includes a pre-processing module and a set of M linear processors coupled to the pre-processing module, M being an integer greater than 1. The pre-processing module includes a wavefront multiplexer having M input ports and M output ports. The wavefront multiplexer receives M input signals at the M input ports, performs a wavefront multiplexing transform on the M input signals and outputs M narrowband signal streams at the M output ports. The wavefront multiplexing transform has an inverse. Each of the M linear processors receives and processes a corresponding one of the M narrowband signal streams, and outputs a corresponding one of M processed narrowband signal streams.
    Type: Application
    Filed: April 2, 2018
    Publication date: August 9, 2018
    Applicant: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C.D. Chang
  • Publication number: 20180205583
    Abstract: A system for remotely generating beams to be concurrently radiated by a downlink broadcast antenna array having N array elements onboard a satellite, N being an integer>1, includes a ground station comprising a digital beam forming (DBF) processor, a wavefront multiplexer, and D/A converters. The DBF processor applies beam weight vectors which include information on a footprint and a pointing direction of a beam to a content data stream and generates N data streams. The wavefront multiplexer having M input ports and M output ports, M being an integer?N, receives the N data streams and M?N diagnostic streams at the M input ports, performs a spatial transform on the M input streams to generate M output streams. The D/A converters convert respectively the M output streams to M baseband signals which are then transformed into an uplink signal to be transmitted to the satellite.
    Type: Application
    Filed: March 12, 2018
    Publication date: July 19, 2018
    Applicant: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C.D. Chang
  • Publication number: 20180205448
    Abstract: A system for communications via first and second transponders includes a transmitter in a ground hub and a VSAT on a moving platform. The transmitter includes a beam shaping processor for forming concurrently first and second beams to transmit first and second streams of data to the VSAT via the first and second transponders, respectively. The VSAT comprises an array antenna, a beam forming network, Rx/Tx processors, and a mini-hub. The array antenna includes N discrete elements arranged as a distributed array and mounted on a fixed structure, N>1. The beam forming network, remotely located from the array antenna and coupled to the array antenna wirelessly or via a fiber, forms concurrent tracking beams for the array antenna to track the transponders. The Rx/Tx processors perform communications functions including modulation, demodulation, channelization, frequency tracking, and timing synchronization. The mini-hub communicates wirelessly with user devices onboard the moving platform.
    Type: Application
    Filed: March 13, 2018
    Publication date: July 19, 2018
    Applicant: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C.D. Chang
  • Patent number: 10027438
    Abstract: An apparatus comprises a wavefront muxing processor receiving first and second input signals to generate first and second output signals on first and second communication channels, respectively, the first and second output signals being at a common frequency slot and having relative differential amplitude and phase delays; and an amplitude and phase adjustment element located at one of the first and second communication channels to adjust the relative differential amplitude and phase delays using an adjustment amount to reduce interference in the first and second communication channels. The first output signal is a weighted sum of the first input signal and the second input signal that is phase shifted by a second phase shift. The second output signal is a weighted sum of the second input signal and the first input signal that is phase shifted by a first phase shift. The two output signals are transmitted to a transponder.
    Type: Grant
    Filed: June 26, 2017
    Date of Patent: July 17, 2018
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Juo-Yu Lee, Donald C. D. Chang, Tzer-Hso Lin
  • Patent number: 10009091
    Abstract: A wireless communications system comprises a transmitting terminal, transponding repeaters located on moving airborne platforms, and receiving terminals located in a first coverage area and a second coverage area. The transmitting terminal comprises a preprocessing unit to receive information data streams, perform a wavefront multiplexing transformation on the information data streams, generate at least a first and a second wavefront multiplexed information data streams, and transmit the first and second wavefront multiplexed information data streams to the receiving terminals via the transponding repeaters.
    Type: Grant
    Filed: July 7, 2015
    Date of Patent: June 26, 2018
    Assignee: Spatial Digital Systems, Inc.
    Inventors: Donald C. D. Chang, Juo-Yu Lee
  • Publication number: 20180175887
    Abstract: One embodiment provides a system that facilitates numerical operation-based erasure coding. During operation, the system determines the bit-width of processing capability of the computing system. The system then determines, based on the bit-width, a number of bits for representing a respective data element from a data stream and a number of data elements based on a number of a dimension of a generator matrix of erasure encoding. The system then obtains the number of data elements from the data stream and converts a respective obtained data element to a corresponding numerical representation. Here, a respective obtained data element is represented by the determined number of bits. The system then generates a code word, which comprises a plurality of coded fragments, of erasure encoding from the numerical representations based on the generator matrix of the erasure encoding.
    Type: Application
    Filed: April 27, 2017
    Publication date: June 21, 2018
    Applicant: PhazrIO Inc.
    Inventors: Donald C. D. Chang, Chi-Kwan J. Cheung, Lara Dolecek, Gary N. Jin, Rocky Chi-Ray Lin
  • Publication number: 20180173589
    Abstract: One embodiment provides a system that facilitates integrated security and high availability. During operation, the system obtains a number of data elements from a data stream based on a number of coded fragments that a code word includes. The system determines one or more bit-level operations for the data elements in such a way that at least one of the one or more bit-level operations becomes eliminated from a process of erasure encoding. The system then obfuscates the data elements based on one or more bit-level operations. Subsequently, the system generates a code word of the erasure encoding from the obfuscated data elements based on the generator matrix. The code word comprises a plurality of coded fragments.
    Type: Application
    Filed: September 29, 2017
    Publication date: June 21, 2018
    Applicant: PhazrIO Inc.
    Inventors: Donald C. D. Chang, Chi-Kwan Jim Cheung, Lara Dolecek, Gary N. Jin, Rocky Chi-Ray Lin
  • Patent number: 10003399
    Abstract: A communication system and method for a deep space spacecraft receiver to perform post-processing to dynamically combine received signal power coherently for pre-processed signal streams radiated non-coherently from a distributed, multiple element, Ka-band transmitting array via multiple concurrent propagation paths. Mutually orthogonal data and pilot signals travel though the multiple propagation paths. A pre-processor utilizing wavefront multiplexing restructures signal streams on the ground into multi-channel wavefrom structures along with injections of pilot signals for diagnostic and probing purposes. These restructured, or “wavefront multiplexed” (WFM) signals are transmitted through propagation channels to a receiver on the spacecraft, wherein adaptive equalization and wavefront de-multiplexing coherently separates the mixtures of received WFM signals.
    Type: Grant
    Filed: June 11, 2015
    Date of Patent: June 19, 2018
    Assignee: Spatial Digital Systems, Inc.
    Inventor: Donald C. D. Chang
  • Patent number: 9995828
    Abstract: A quiet zone generation technique for acoustic/audio signals is proposed for mitigation of selected noise or interferences over limited areas in free space by injecting the very acoustic noise, interference, or audio feedback signals via iterative processing, generating quiet zones dynamically. This creates undesired noise-free quiet zones. Optimization loops operating iteratively to electronically process cancellation signals consist of three interconnected functional blocks: (1) an acoustic injection array, consisting of pick-up arrays to obtain the interference signals, beam forming networks for element weighting and/or re-positioning, and array elements for noise injections, (2) a diagnostic network with strategically located probes, and (3) an optimization processor with cost minimization algorithms to calculate element weights for updating.
    Type: Grant
    Filed: January 18, 2011
    Date of Patent: June 12, 2018
    Assignee: Spatial Digital Systems, Inc.
    Inventors: Donald C. D. Chang, Steve Chen
  • Publication number: 20180159626
    Abstract: A data communication system comprises an optical transferring device, optical network units, and user processors. The optical transferring device splits a received optical signal into split optical signals. Each optical network unit transforms a respective split optical signal into M first electronic signals, M>1. Each user processor comprises an input mapping unit to map the respective M first electronic signals into N second electronic signals, N?M; an equalization processor to equalize the N second electronic signals and generate a set of N equalized electronic signals; a wave-front demultiplexer to perform a wave-front demultiplexing transform on the N equalized electronic signals, and output N wave-front demultiplexed signals, each of the N wave-front demultiplexed signals being a unique linear combination of the N equalized electronic signals; and an output mapping unit to map the N wave-front demultiplexed signals into at least M third digital electronic data signals.
    Type: Application
    Filed: January 29, 2018
    Publication date: June 7, 2018
    Applicant: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C.D. Chang