Patents Assigned to Spatial Digital Systems, Inc.
  • Patent number: 11368195
    Abstract: Embodiments of a communications system with multiple active scattering devices to service multiple users either indoor or outdoor over same spectrum in a communication network and a method for the system are generally described herein. Signals streams for transmission to users in spoke-and-hub configurations will utilize multiple active scattering devices. Three categories of operational concepts are presented: (1) multiple scattering devices arranged geometrically bundled together to function as active mirrors or retro-directive repeaters, (2) distributed man-made scattering devices placed to enhance channel bandwidth in between a hub and a common service area via frequency re-use, and (3) organizing distributed active scattering devices by remote beamforming for servicing a small common coverage area indoor or outdoor with enhanced bandwidth.
    Type: Grant
    Filed: May 28, 2014
    Date of Patent: June 21, 2022
    Assignee: Spatial Digital Systems, Inc.
    Inventors: Donald C. D. Chang, Juo-Yu Lee
  • 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
  • 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
  • Patent number: 9935647
    Abstract: A broadband digital beam forming system comprises a set of Q pre-processing modules, Q being an integer greater than or equal to 2, and a set of M digital beam forming modules in communication with the Q preprocessing modules. Each of the Q preprocessing modules receives a respective one of Q broadband input signal streams and outputs M narrowband signal streams, M being an integer greater than or equal to 2. The total number of narrowband signal streams outputted by the Q pre-processing modules is Q times M. Each of the M digital beam forming modules receives corresponding Q narrowband signal streams of the Q times M narrowband signal streams, and outputs R beam signals, R being an integer greater than or equal to 1. The system further comprises a set of R post-processing modules in communication with the M digital beam forming modules.
    Type: Grant
    Filed: November 13, 2016
    Date of Patent: April 3, 2018
    Assignee: Spatial Digital Systems, Inc.
    Inventor: Donald C. D. Chang
  • Patent number: 9917719
    Abstract: A satellite broadcasting system is achieved where remote beam forming processors combined with wavefront multiplexers located among distributed ground stations are used to control downlink beam footprints and pointing directions. Digital beam forming (DBF) techniques allow a single satellite download broadcast antenna array to generate multiple independently pointed simultaneous downlinks, which may contain distinct information content. Allocation of some uplink back-channel elements as diagnostic signals allows for continuous calibration of uplink channels, improving downlink broadcast array and user broadcast performance. Wavefront multiplexing/demultiplexing allows all array element signals to be radiated by the broadcasting antenna array, with simultaneous propagation from ground stations to the broadcasting satellites through available parallel propagation channels in the uplinks of feeder links, with equalized amplitude and phase differentials.
    Type: Grant
    Filed: July 21, 2014
    Date of Patent: March 13, 2018
    Assignee: Spatial Digital Systems, Inc.
    Inventor: Donald C. D. Chang
  • Patent number: 9917635
    Abstract: Signals of data streams for transmission to user equipment (UE) in spoke-and-hub configurations will utilize multiple transponders of satellites. Radiation patterns from ground terminals with distributed apertures feature orthogonal beams (OB). A tracking OB beam from a moving platform dynamically shall autonomously be formed as a shaped beam by a digital-beam-forming (DBF) network with a peak to a desired satellite, and nulls to undesired satellites to minimize mutual interferences among multiple satellite spatially. Ground hubs and mobile terminals feature “coherent” bandwidth aggregating capability from multiple available but non-contiguous slices of frequency slots in many transponders by wavefront multiplexing/demultiplexing (WF muxing/demuxing) techniques. These individual frequency slots must be dynamically selected, calibrated and equalized continuously in receivers via embedded probing signals as a part of WF muxing/demuxing techniques.
    Type: Grant
    Filed: March 10, 2014
    Date of Patent: March 13, 2018
    Assignee: Spatial Digital Systems, Inc.
    Inventor: Donald C. D. Chang
  • Patent number: 9882641
    Abstract: A data communication system comprises a central office processor which comprises a first input mapping unit, a first wave-front multiplexer, and a first output mapping unit. The first input mapping unit receives and dynamically maps digital data into a plurality of first electronic signals. The first wave-front multiplexer is coupled to the first input mapping unit to receive the first electronic signals, perform a wave-front multiplexing transformation on the first electronic signals, and output wave-front multiplexed signals, each of the wave-front multiplexed signals being a linear combination of the first electronic signals. The first output mapping unit is coupled to the first wave-front multiplexer to receive and dynamically map the wave-front multiplexed signals into second electronic signals.
    Type: Grant
    Filed: July 17, 2017
    Date of Patent: January 30, 2018
    Assignee: Spatial Digital Systems, Inc.
    Inventor: Donald C. D. Chang
  • Patent number: 9866300
    Abstract: Four independent technologies are incorporated in this invention to efficiently and cost effectively implement dynamic last mile connectivity. The four technologies are passive optical networks (PON), Small cell, wavefront multiplexing (or K-muxing), and digital beam forming (DBF). We have filed US patents for communications architectures featuring K-muxing overlaid over low cost of PON. Those inventions relate particularly to resource allocation in passive optical networks (PON) via wavefront multiplexing (WF-muxing or K-muxing) and wavefront demultiplexing (WF-demuxing or K-demuxing). The “WF-muxing in PON” can be configured for performing remote digital beam forming (RDBF) over a service area covered by multiple small cells. The RDBF may generate multiple shaped beams with enhanced connectivity and better isolations over a same frequency slot concurrently to serve multiple users over the coverage area.
    Type: Grant
    Filed: January 12, 2016
    Date of Patent: January 9, 2018
    Assignee: Spatial Digital Systems, Inc.
    Inventors: Donald C. D. Chang, Juo-Yu Lee, Steve K. Chen
  • Patent number: 9866226
    Abstract: An analog-to-digital conversion system includes a first processor, a bank of N analog-to-digital converters, and a second processor. The first processor receives M input signal streams, performs a wave-front multiplexing transform that includes a first set of wave-front vectors on the M input signal streams in analog domain and outputs concurrently N mixed signal streams, M and N being integers and N?M>1. The N analog-to-digital converters convert the N mixed signal streams from analog format to digital format and output concurrently N digital data streams. The second processor receives the N digital data streams, performs a wave-front de-multiplexing transform that includes a second set of wave-front vectors on the N digital data streams in digital domain and outputs concurrently N output data streams such that the N output data streams include M output data streams that correspond respectively to the M input signal streams.
    Type: Grant
    Filed: October 31, 2016
    Date of Patent: January 9, 2018
    Assignee: Spatial Digital Systems, Inc.
    Inventors: Donald C.D. Chang, Tzer-Hso Lin, Yuanchang Liu
  • Patent number: 9848094
    Abstract: Presented are cloud storage architectures for private data of scanned documents uploaded from smart phone 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 data in multiple data storages linking to said second data sets at said uploading site. In accordance with an embodiment of present invention 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: December 19, 2017
    Assignee: Spatial Digital Systems, Inc.
    Inventors: Donald C. D. Chang, Juo-Yu Lee, Steve K. Chen
  • Patent number: 9829580
    Abstract: A system for reducing undesired interference in a target zone is disclosed. The system comprises a set of M pickup sensors, a beam forming network coupled to the M pickup sensors, and a set of N injectors coupled to the beam forming network. The M pickup sensors pick up undesired signals in real time and generate M pickup signals, M being an integer greater than or equal to 1. The beam forming network comprises a set of M beam forming modules. Each of the M beam forming modules receives a respective one of the M pickup signals and generates N intermediate signals, N being an integer greater than 1. The N intermediate signals generated by each of the M beam forming modules are combined correspondingly with remaining intermediate signals generated by remaining M?1 beam forming modules to generate N interference signals. The N injectors receive and radiate the N interference signals to the target zone.
    Type: Grant
    Filed: November 22, 2016
    Date of Patent: November 28, 2017
    Assignee: Spatial Digital Systems, Inc.
    Inventors: Donald C. D. Chang, Michael T. H. Lin, Steve Chen
  • Patent number: 9793977
    Abstract: A communications system for providing recovery communication service to users in a coverage area affected by an emergency disruption of normal communication services. The system comprises a ground hub serving as a gateway to terrestrial networks including a dispatch center and configured to communicate with at least three mobile airborne platforms roving over the coverage area via respective feeder-links in a Ku or Ka band. A first mobile airborne platform communicates in a first frequency band with emergency workers that are working in the coverage area and associated with the dispatch center. A second mobile airborne platform communicates, in place of at least one disrupted base station in the coverage area, with user mobile phones in mobile phone frequency bands or user personal devices in WiFi bands located in the coverage area. A third mobile airborne platform generates real-time imaging of surfaces located in the coverage area.
    Type: Grant
    Filed: April 11, 2017
    Date of Patent: October 17, 2017
    Assignee: Spatial Digital Systems, Inc.
    Inventor: Donald C. D. Chang
  • Patent number: 9780859
    Abstract: Aircrafts flying near Earth or naval vessels are used as active scattering platforms in a multipath communications channel in MIMO communications systems. These man-made platforms in a communications channel, with techniques of beam forming and wavefront multiplexing in both transmitters at source and receivers at destinations enhance the ability to coherently combine the power of the communication signals, and improve the signal-to-noise ratio in addition to the MIMO advantage of multiple times of channel capacity over a finite bandwidth via frequency reuse. These platforms may be stationary, mobile ground based, or ocean surface based. They may also be airborne, or space borne. A swarm of 10's micro-UAV based mini-transponders is an example through active scattering of these micro-UAV to generate 10× more available bandwidth between a base station and ground mobile users over same bandwidth.
    Type: Grant
    Filed: February 28, 2014
    Date of Patent: October 3, 2017
    Assignee: Spatial Digital Systems, Inc.
    Inventors: Donald C. D. Chang, Juo-Yu Lee
  • Patent number: 9762309
    Abstract: This invention aims to present a smart and dynamic power amplifier module that features both power combining and power sharing capabilities. The proposed flexible power amplifier (PA) module consists of a pre-processor, N PAs, and a post-processor. The pre-processor is an M-to-N wavefront (WF) multiplexer (muxer), while the post processor is a N-to-M WF de-multiplexer (demuxer), where N?M?2. Multiple independent signals can be concurrently amplified by a proposed multi-channel PA module with a fixed total power output, while individual signal channel outputs feature different power intensities with no signal couplings among the individual signals. In addition to basic configurations, some modules can be configured to feature both functions of parallel power amplifiers and also as M-to-M switches. Other programmable features include configurations of power combining and power redistribution functions with a prescribed amplitude and phase distributions, as well as high power PA with a linearizer.
    Type: Grant
    Filed: September 27, 2013
    Date of Patent: September 12, 2017
    Assignee: Spatial Digital Systems, Inc.
    Inventor: Donald C. D. Chang
  • Patent number: 9749033
    Abstract: A receive only smart antenna with a command pointing option for communicating with geostationary satellites that autonomously detects the directions from which desired signal are received, and steer the multiple beams accordingly. An array feed is used to illuminate a parabolic reflector. Each feed element of the receive only smart antenna is associated with a unique beam pointing direction. As a receiver is switched to different feed elements, the far-field beam is scanned, making it possible to track a geostationary satellite in a slightly inclined orbit. This eliminates the need for mechanical tracking and maintains high antenna gain in the direction of the geostationary satellite. The receive only smart antenna also features capabilities to form multiple simultaneous beams supporting operations of multiple geo-satellites in closely spaced slightly inclined orbits. The designs can support orthogonal beams for enhanced bandwidth capacity via multiple beams with excellent spatial isolation.
    Type: Grant
    Filed: July 29, 2014
    Date of Patent: August 29, 2017
    Assignee: Spatial Digital Systems, Inc.
    Inventor: Donald C. D. Chang
  • Patent number: 9712235
    Abstract: A data communication system comprises a wave-front multiplexer configured to wave-front multiplex first electronic signals into second electronic signals. The data communication system further comprises an electronic-to-optical converter configured to convert a third electronic signal carrying information associated with the second electronic signals into a first optical signal; and an optical transferring module configured to split the first optical signal into second optical signals, wherein each of the second optical signals carries the same data as the first optical signal carries. The data communication system further comprises optical-to-electronic converters configured to convert the second optical signals into fourth electronic signals; and wave-front demultiplexers each configured to wave-front demultiplex one of the fourth electronic signals into fifth electronic signals equivalent to the first electronic signals respectively.
    Type: Grant
    Filed: December 22, 2015
    Date of Patent: July 18, 2017
    Assignee: Spatial Digital Systems, Inc.
    Inventor: Donald C. D. Chang
  • Patent number: 9692549
    Abstract: Presented are methods that utilize wavefront multiplexing for enabling linearly-polarized terminals to access circularly-polarized satellite transponders. The methods disclosed herein feature (1) polarization formation capability that renders transmitted signal conditioned on circularly-polarized channels through multiple linearly-polarized feeds, and (2) polarization-conversion capability that compensate path differentials introduced by electromagnetic wave propagation channels. Data streams to be transmitted are pre-processed by a wavefront multiplexer into multiple wavefront components in linear polarization formats, where signals from respective data streams are replicated into linearly-polarized sub-channels. These replicated data streams are linked via a unique complex weighting vector (amplitude and phase or their equivalents), or “wavefront”, which are also linked by various spatially independent wavefronts.
    Type: Grant
    Filed: June 2, 2015
    Date of Patent: June 27, 2017
    Assignee: Spatial Digital Systems, Inc.
    Inventors: Juo-Yu Lee, Donald C. D. Chang, Tzer-Hso Lin
  • Patent number: 9647347
    Abstract: A system is provided that enhances the throughput and reliability of wireless communications by providing multi-beam user terminals that exhibit directional discrimination. Multiple wireless communication channels are matched with multiple beams created from an array antenna by a beam-forming processor. The multiple wireless communication channels are bonded into a single virtual channel, thereby increasing data bandwidth while reducing interference and multi-path effects that can degrade communications. The beam-forming function may be performed in a dedicated beam-forming processor or may reside within a general-purpose microprocessor located in the user terminal. In addition, a wireless communications system with access points featuring multiple beams that exhibit directional discrimination that can concurrently support multiple users with multi-beam terminals via a common frequency channel.
    Type: Grant
    Filed: October 17, 2011
    Date of Patent: May 9, 2017
    Assignee: Spatial Digital Systems, Inc.
    Inventor: Donald C. D. Chang
  • Patent number: 9628250
    Abstract: An advanced digital beam forming technique is achieved that is capable of simultaneously forming multiple beams and attenuating the cross-pol component at multiple locations. The proposed invention, comprising a series of signal inputs, optimization loops and weighting processes, successfully eliminates the side effect of an increase of the cross-pol in the process of beam-forming, thus reducing potential interference. This technique utilizes the orthogonally polarized signal component which is already available and can minimize both the horizontally polarized and vertically polarized cross-pol at the same time. The complexity of computation can be reduced by using only part of the orthogonal polarized components in the optimization.
    Type: Grant
    Filed: March 24, 2011
    Date of Patent: April 18, 2017
    Assignee: Spatial Digital Systems, Inc.
    Inventors: Donald C. D. Chang, Frank Lu, Yulan Sun