Patents Assigned to SPATIAL DIGITAL SYSTEMS
  • Patent number: 9231729
    Abstract: A data communication system comprises a wave-front multiplexer configured to wave-front multiplex first electronic signals into second electronic signals. An electronic-to-optical converter is configured to convert a third electronic signal carrying information associated with the second electronic signals into a first optical signal. An optical transferring module is 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. Optical-to-electronic converters are configured to convert the second optical signals into fourth electronic signals. Wave-front demultiplexers each are configured to wave-front demultiplex the fourth electronic signals into fifth electronic signals equivalent to the first electronic signals respectively.
    Type: Grant
    Filed: February 27, 2013
    Date of Patent: January 5, 2016
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C. D. Chang
  • Patent number: 9166673
    Abstract: A direct broadcasting satellite (DBS) system features a capability of coherently combining amplified signals powers from various broadcasting transponders without modifying the satellite segment. Organized DBS transponders would function as an equivalent DBS transponder with a higher EIRP. Power allocations are via a mechanism in an uplink transmitter in a ground segment and power combining mechanisms are in user receivers in a user segment. Specifically, the transmitter generates mixtures of input signals by using Wavefront-Multiplexing and transmits wavefront-multiplexed (WFM) signals which are sent concurrently through multiple parallel channels of transponders in the satellite segment. A receiver in the user segment separates the mixtures of received amplified WFM signals and coherently combines amplified components by various transponders by adaptive equalizing and Wavefront De-Multiplexing processors.
    Type: Grant
    Filed: August 27, 2013
    Date of Patent: October 20, 2015
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C. D. Chang
  • Patent number: 9100085
    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 de-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: October 25, 2011
    Date of Patent: August 4, 2015
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C. D. Chang
  • Patent number: 9077427
    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: February 6, 2012
    Date of Patent: July 7, 2015
    Assignee: SPATIAL DIGITAL SYSTEMS, INC.
    Inventor: Donald C. D. Chang
  • Publication number: 20140266895
    Abstract: A novel wide null forming system achieves both wide bandwidth and beam width null through employing an antenna array to receive and transmit signals to which a complex null weight vector, calculated by perturbation program, is applied. The novel wide null forming system includes a multiple-element antenna array for receiving or transmitting signals. Multiple conditioning units matching the number of elements is present to condition the signals for proper reception and analysis, after which a series of complex multiplier processors adds complex weights. After being weighted each constituent beam is combined in an adding processor to form one composite beam for use by the user.
    Type: Application
    Filed: June 2, 2014
    Publication date: September 18, 2014
    Applicant: SPATIAL DIGITAL SYSTEMS, INC.
    Inventors: Donald C.D. Chang, Yulan Sun, Yuanchang Liu
  • Publication number: 20130071105
    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 de-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: Application
    Filed: October 25, 2011
    Publication date: March 21, 2013
    Applicant: SPATIAL DIGITAL SYSTEMS
    Inventor: Donald C. D. Chang
  • Publication number: 20130070677
    Abstract: Aircrafts or unmanned air vehicles flying near Earth are used as airborne communications towers or relays. Using techniques of ground based beam forming and wavefront multiplexing enhance the ability to coherently combine the power of the communication signals, and improve the signal-to-noise ratio.
    Type: Application
    Filed: September 21, 2012
    Publication date: March 21, 2013
    Applicant: SPATIAL DIGITAL SYSTEMS
    Inventor: Donald C. D. Chang
  • Publication number: 20120326925
    Abstract: An advanced multiple-beam GPS receiving system is achieved that is capable of simultaneously tracking multiple GPS satellites independently, detecting multiple interference signals individually, and suppressing directional gain in the antenna pattern of each beam in the interference directions. The GPS receiving system can be used for both planar and non-planar receiving arrays, including arrays that are conformally applied to the surface of a platform such as an aircraft. The GPS receiver combines spatial filtering and acquisition code correlation for enhanced rejection of interfering sources. Enhanced gain in the direction of GPS satellites and the ability to shape the beam patterns to suppress gain in the direction of interfering sources make the GPS receiving system largely insensitive to interfering and jamming signals that plague conventional GPS receivers.
    Type: Application
    Filed: July 16, 2012
    Publication date: December 27, 2012
    Applicant: SPATIAL DIGITAL SYSTEMS
    Inventor: Donald C. D. Chang
  • Publication number: 20120328036
    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: Application
    Filed: October 17, 2011
    Publication date: December 27, 2012
    Applicant: SPATIAL DIGITAL SYSTEMS
    Inventor: Donald C. D. Chang
  • Publication number: 20120319772
    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: Application
    Filed: July 12, 2011
    Publication date: December 20, 2012
    Applicant: SPATIAL DIGITAL SYSTEMS
    Inventor: Donald C. D. Chang
  • Publication number: 20120301136
    Abstract: A communication system and method that allows a transmitter segment (ground end of uplink segment) to dynamically combine power from a plurality of propagation channels (transponders) to improve power levels of signals being transmitted, without affecting the receiver segment (user end of downlink segment) and the propagation segment (space segment), and without modifying propagation apparatus configurations (satellite). Specifically, the transmitter segment generates mixtures of input signals by using Wavefront-Multiplexing and transmits wavefront-multiplexed (WFM) signals through propagation channels to a receiver segment that coherently separates the mixtures of received WFM signals by using adaptive equalization and Wavefront-De-Multiplexing.
    Type: Application
    Filed: November 23, 2011
    Publication date: November 29, 2012
    Applicant: SPATIAL DIGITAL SYSTEMS
    Inventor: Donald C. D. Chang
  • Publication number: 20120274499
    Abstract: The proposed MIMO radar imaging method takes advantages of measurement techniques of spatial frequency components of an RF area image from radar returns. To minimize size, weight and power (SW&P), minimum redundancy arrays (MRAs) for both Tx and Rx with unique geometries are proposed. MIMO waveforms are utilized to index the radiated illuminations to a targeted area in the forms of 1-D spatial frequency components. Consequently, the corresponding radar returns from the targeted field of view (FOV) are captured by the Rx MRA. With the knowledge of uniquely designed MRA array geometries, virtual beams are synthesized in Rx processor; usually one Tx and many contiguous Rx fan beams. These virtual beams may be dynamically “moved” to different beam positions. The elongated beam direction for Tx fan beam and that for Rx fan beams are perpendicular to one another. Thus intersections of the Tx fan-beam and many Rx fan-beams are the very areas of radar returns. We refer those areas as virtual beam crosses.
    Type: Application
    Filed: April 29, 2011
    Publication date: November 1, 2012
    Applicant: SPATIAL DIGITAL SYSTEMS
    Inventor: Donald C. D. Chang
  • Publication number: 20120183295
    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: Application
    Filed: September 13, 2011
    Publication date: July 19, 2012
    Applicant: SPATIAL DIGITAL SYSTEMS
    Inventor: Donald C. D. Chang
  • Publication number: 20120069918
    Abstract: The present invention features novel methods of implementing configurable arrays for personal portable devices including hand-held mobile devices and re-locatable wireless devices, utilizing a wireless communications system that employs multiple individual hubs and/or base-stations. The digital beam forming (DBF) methodology utilizes multiple low gain elements conformal to the mechanical contours of handheld devices to function as arrays. The distributed N element arrays dynamically provide the options of reconfigurable shaped beams with near hemispheric radiation patterns for various handheld orientations and conditions by various users, while also supporting operations of multiple orthogonal beams concurrently connecting to multiple hubs. The larger the N becomes, the more flexibility the residing devices can provide.
    Type: Application
    Filed: September 19, 2011
    Publication date: March 22, 2012
    Applicant: SPATIAL DIGITAL SYSTEMS
    Inventor: Donald C. D. Chang
  • Publication number: 20120064759
    Abstract: A retractable mobile device power module comprises of a plug to power outlet, a retractable power cord, an adapter, and a retractor. With this design, power supply for mobile devices can be compact and low profile. Besides providing power, this design can be used for data transmission as well.
    Type: Application
    Filed: November 22, 2010
    Publication date: March 15, 2012
    Applicant: SPATIAL DIGITAL SYSTEMS
    Inventors: Yuanchang Liu, Donald C. D. Chang, Derrick Chu
  • Publication number: 20120051284
    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: Application
    Filed: November 8, 2011
    Publication date: March 1, 2012
    Applicant: SPATIAL DIGITAL SYSTEMS
    Inventor: Donald C. D. Chang
  • Publication number: 20120026937
    Abstract: The invention is about a method and apparatus for grouping multiple satellite transponders with both (LP) polarization formats in different frequencies through Wave-Front (WF) Multiplexing (muxing) techniques for ground terminals with incompatible (CP) polarization formats. As a result of this invention, linear polarized (LP) transponders can be accessed and efficiently utilized by circularly polarized (CP) ground terminals and vice versa. This invention consists of conventional ground terminals, a unique organization of space assets, and a unique polarization alignment processor. The applications of wavefront multiplexing techniques to satellite communications offer many potential advantages, including improved flexibility and utility efficiency of existing space assets. Our proposed “Polarization Utility Waveforms” is an entirely new concept in VSAT and Earth Station Antenna diversity.
    Type: Application
    Filed: June 29, 2011
    Publication date: February 2, 2012
    Applicant: SPATIAL DIGITAL SYSTEMS
    Inventor: DONALD C. D. CHANG