Patents by Inventor Ross D. Murch

Ross D. Murch 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: 8280443
    Abstract: Disclosed are systems and methods which provide high bandwidth data communication with respect to a large coverage area using smart antenna and/or directional antenna (referred to herein as multi-beam antenna) technology. Circuitry may be provided at a WLAN AP to provide selection of particular antenna beams used in the downlink and/or uplink, control of multicast transmission, control of unicast transmission, and to provide antenna pattern shaping techniques. Embodiments implement multi-beam antenna technology with little or no hardware modifications to AP circuitry. Other embodiments implement multi-beam technology using radio front-end and/or radio hardware modifications to AP circuitry. Various diversity techniques may be implemented, such as selection diversity, maximum ratio combining, and equal gain combing. To provide desired antenna pattern shaping, phase offsets with respect to a signal as transmitted in each antenna beam may be employed.
    Type: Grant
    Filed: July 30, 2004
    Date of Patent: October 2, 2012
    Assignee: Hong Kong Applied Science and Technology Research Institute Co., Ltd.
    Inventors: Meixia Tao, Cheong Yui Wong, Yan Wang, Kin Nang Lau, Ross D. Murch, Soung C. Liew, Douglas R. George
  • Patent number: 7629930
    Abstract: A system for reducing unwanted signals comprises a ground plane, a first active component disposed so as to cause signals in the ground plane, a second active component disposed so as to cause signals in the ground plane, wherein the ground plane provides a path for the signals from the first active component to affect the second active component and for the signals from the second active component to affect the first active component, and a filter element configured as a pattern in the ground plane receiving and attenuating the signals from each of the first and second active components.
    Type: Grant
    Filed: October 20, 2006
    Date of Patent: December 8, 2009
    Assignee: Hong Kong Applied Science and Technology Research Institute Co., Ltd.
    Inventors: Ross D. Murch, Chi-Yuk Chiu, Corbett Rowell
  • Publication number: 20080094302
    Abstract: A system for reducing unwanted signals comprises a ground plane, a first active component disposed so as to cause signals in the ground plane, a second active component disposed so as to cause signals in the ground plane, wherein the ground plane provides a path for the signals from the first active component to affect the second active component and for the signals from the second active component to affect the first active component, and a filter element configured as a pattern in the ground plane receiving and attenuating the signals from each of the first and second active components.
    Type: Application
    Filed: October 20, 2006
    Publication date: April 24, 2008
    Applicant: Hong Kong Applied Science and Technology Research Institute Co., Ltd.
    Inventors: Ross D. Murch, Chi-Yuk Chiu, Corbett Rowell
  • Patent number: 5960032
    Abstract: High-rate bit transmitted data is serial to parallel converted into low-rate bit streams in a similar fashion to multicarrier or multitone modulation. However, in contrast to the multicarrier method, each low-rate bit stream is modulated using direct-sequence spread-spectrum. By selecting the processing gain properly the total required bandwidth will be of the same order as the original high-rate data stream, thereby gaining the inherent benefit of multipath rejection without expanding the bandwidth of the original high-rate stream.
    Type: Grant
    Filed: September 20, 1995
    Date of Patent: September 28, 1999
    Assignee: The Hong Kong University of Science & Technology
    Inventors: Khaled Ben Letaief, Justin C-I Chuang, Ross D. Murch