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: 8706167
    Abstract: A communication system communications system for communicating with mobile user terminals includes a base station having an adaptive antenna with a plurality of panels. Each of the plurality of panels are arranged to have a different field of view. Each panel has a plurality of main array antenna elements for simultaneously generating a plurality of dynamic communication beams that move with the mobile terminals and a plurality of auxiliary elements separate from the plurality of main array antenna elements used for interference cancelling signals cancelling interference between the plurality of dynamic communication beams generated by the plurality of main array elements. A gateway station is coupled to the base station. The gateway station forms a plurality of beams commands for each of the plurality of panels by communicating a plurality of control signals to the base station to form the plurality of dynamic communication beams.
    Type: Grant
    Filed: February 20, 2013
    Date of Patent: April 22, 2014
    Assignee: The DIRECTV Group, Inc.
    Inventors: Donald C. D. Chang, Wah L. Lim, Ming U. Chang
  • Publication number: 20140104105
    Abstract: A system for allowing ground terminals, specifically mobile ground terminals, to dynamically and electronically realign signal polarizations to match that of incoming and outgoing signal polarizations from designated space assets, specifically communications from satellites, comprising an adaptive re-orientation technique based on a cost minimization function, and a means of direct calculations of weighting components based on the knowledge of the orientation and bearing of both the satellites and the ground terminals. The embodiment will allow a mobile ground terminal to electronically realign itself to the signals of a satellite, without the need for mechanical processes to physically re-orient the antenna array.
    Type: Application
    Filed: December 15, 2013
    Publication date: April 17, 2014
    Inventor: Donald C.D. Chang
  • Publication number: 20140081989
    Abstract: Security on data storage and transport are important concerns 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. In short, the WF muxed data storage solution enhances data security and data redundancy by, respectively, creating a new dimension to existing security/privacy methods and significantly reducing the storage space needed for data redundancy.
    Type: Application
    Filed: July 29, 2013
    Publication date: March 20, 2014
    Inventors: Steve K Chen, Donald C.D. Chang, Juo-Yu Lee
  • Patent number: 8643562
    Abstract: A compact patch antenna array for mobile terminal applications comprising: a plurality of radiators mounted on one surface of a dielectric, with a ground plane being mounted on the other side of the dielectric. Beneath the ground plane, another dielectric with feeding network is placed. Other embodiments are described and shown in FIG. 2.
    Type: Grant
    Filed: July 30, 2010
    Date of Patent: February 4, 2014
    Inventors: Donald C. D. Chang, Yuanchang Liu
  • Publication number: 20140022984
    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: September 27, 2013
    Publication date: January 23, 2014
    Inventor: Donald C.D. Chang
  • Patent number: 8634760
    Abstract: A system for allowing ground terminals, mobile or stationary, to dynamically and electronically re-align signal polarizations to match that of incoming signal polarizations from transmitting sources. An adaptive re-orientation technique utilizes a cost minimization function to determine the difference between actual orientation values and desired orientation values. Calculations of satellite and ground terminal orientations and bearings to create weighting components allow a mobile ground terminal to electronically realign itself to the signals of a transmitting source, thereby eliminating the need for physically re-orienting the antenna array through mechanical processes.
    Type: Grant
    Filed: July 30, 2010
    Date of Patent: January 21, 2014
    Inventors: Donald C. D. Chang, Frank Lu, Yulan Sun
  • Publication number: 20130333544
    Abstract: A concurrent multi-channel data process is presented to utilize wavefront multiplexing for data storage and data stream transport in a distribution network, with additional applications for multi-media recording and data communications via transponding satellites. 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 phase weighting vector, or “wave-front”, which are also linked by various spatially orthogonal wavefronts. Additionally, probing signals are embedded and linked via some of the orthogonal wavefronts. Aggregated signals in sub-channels are unique linear combinations of all input data streams.
    Type: Application
    Filed: July 10, 2013
    Publication date: December 19, 2013
    Inventors: Steve K Chen, Donald C.D. Chang
  • Publication number: 20130321206
    Abstract: An outdoor unit of a satellite ground terminal is capable of simultaneously receiving satellite signals or data streams originated from multiple different orbital satellites operating at the same frequency in a satellite communication frequency band such as Ka band or Ku band by multiple concurrent orthogonal beams, which are generated by multiple analogue or digital beam forming networks of the outdoor unit and an antenna, such as multiple-beam antenna or direct radiating/reception array, of the outdoor unit. Each of the orthogonal beams has a beam peak in the desired direction and multiple nulls in the interference directions.
    Type: Application
    Filed: May 29, 2013
    Publication date: December 5, 2013
    Inventor: Donald C.D. Chang
  • Publication number: 20130302034
    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: July 10, 2013
    Publication date: November 14, 2013
    Inventor: Donald C.D. Chang
  • Patent number: 8570103
    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: July 12, 2011
    Date of Patent: October 29, 2013
    Inventor: Donald C. D. Chang
  • Patent number: 8547897
    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: Grant
    Filed: November 23, 2011
    Date of Patent: October 1, 2013
    Inventor: Donald C. D. Chang
  • Patent number: 8538326
    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: Grant
    Filed: June 29, 2011
    Date of Patent: September 17, 2013
    Inventor: Donald C. D. Chang
  • Publication number: 20130223840
    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 configured to convert a third electronic signal carrying information associated with said second electronic signals into a first optical signal; an optical transferring module configured to split said first optical signal into second optical signals, wherein each of said second optical signals carries substantially the same data as said first optical signal carries; optical-to-electronic converters configured to convert said second optical signals into fourth electronic signals; wave-front demultiplexers each configured to wave-front demultiplex one of said fourth electronic signals into fifth electronic signals substantially equivalent to said first electronic signals respectively.
    Type: Application
    Filed: February 27, 2013
    Publication date: August 29, 2013
    Inventor: Donald C.D. Chang
  • Publication number: 20130222184
    Abstract: A receive-only smart antenna with a directional-point command capability for communication with geostationary satellites, allowing autonomous detection of received signals in order to allow steerage of multiple beams. An array feed is used to illuminate a parabolic reflector, with each feed element of the smart antenna associated with a unique beam-pointing direction. As the receiver switches to different feed elements, the far-field beam is scanned, making it possible to track a geostationary satellite in slightly inclined orbits, eliminating the need for mechanical tracking mechanisms while maintaining high antenna gain in the direction of the satellite. The receive-only smart antenna also features capabilities for forming multiple simultaneous beams supporting operations of multiple geo-satellites closely space in slightly inclined orbits. The designs can support orthogonal beams for enhanced bandwidth capacity via multiple beams with excellent spatial isolation.
    Type: Application
    Filed: February 21, 2013
    Publication date: August 29, 2013
    Inventor: Donald C.D. Chang
  • Publication number: 20130214955
    Abstract: A novel noise injection technique is presented to improve dynamic range with low resolution and low speed analog to digital converters. This technique combines incoming signal and noise signal with wave front de-multiplexer and split into several channels. Then low resolution and low speed analog to digital converters are used to sample each channels. All signals are recovered using wave front multiplexer. For advanced design, ground diagnostic signals with optimizing processor can be added to guarantee recovery quality.
    Type: Application
    Filed: February 8, 2013
    Publication date: August 22, 2013
    Inventor: Donald C.D. Chang
  • 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
  • Patent number: 8396513
    Abstract: A communication system has a base station having an adaptive antenna with a plurality of main array antenna elements for generating a plurality of communication beams. The system further includes a gateway station coupled to the base station. The gateway station forms a plurality of beams commands by communicating plurality of a control signals to the base station to form the communication beams.
    Type: Grant
    Filed: May 15, 2001
    Date of Patent: March 12, 2013
    Assignee: The DIRECTV Group, Inc.
    Inventors: Donald C. D. Chang, Wah L. Lim, Ming U. Chang
  • Patent number: 8395546
    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: February 9, 2011
    Date of Patent: March 12, 2013
    Assignee: Spatial Digital Systems, Inc
    Inventor: Donald C. D. Chang
  • Patent number: 8384572
    Abstract: A novel noise injection technique is presented to improve dynamic range with low resolution and low speed analog to digital converters. This technique combines incoming signal and noise signal with wave front de-multiplexer and split into several channels. Then low resolution and low speed analog to digital converters are used to sample each channels. All signals are recovered using wave front multiplexer. For advanced design, ground diagnostic signals with optimizing processor can be added to guarantee recovery quality.
    Type: Grant
    Filed: January 5, 2011
    Date of Patent: February 26, 2013
    Assignee: Spatial Digital Systems Inc.
    Inventors: Tzer-Hso Lin, Yuanchang Liu, Donald C. D. Chang