Patents by Inventor Malcolm C. Betts

Malcolm C. Betts 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).

  • Communications system with protection switching using individual selectors
    Patent number: 4837760
    Abstract: An optical fiber communications system with a plurality of bidirectional channels and a protection channel is disclosed. Each channel has a respective identity which is transmitted in the traffic of that channel and in the event of a protection switch is identified in the protection channel traffic. A protection switch is effected by detecting a channel failure at the receive end of a span, transmitting a protection request on the return channel back to the transmit end of the span, and using this request in a controller for the channel to effect a protection switch, using an individual selector for the channel, if a priority scheme allows. The controllers are enabled or disabled under software control following a protection switch in accordance with the prevailing priority scheme. The arrangement provides for rapid protection switching.
    Type: Grant
    Filed: August 2, 1985
    Date of Patent: June 6, 1989
    Assignee: Northern Telecom Limited
    Inventors: David I. Reid, John C. Ellson, Malcolm C. Betts
  • Communications system with protection switching and channel identities
    Patent number: 4646286
    Abstract: An optical fiber communications system with a plurality of bidirectional channels and a protection channel is disclosed. Each channel has a respective identity which is transmitted in the traffic of that channel and in the event of a protection switch is identified in the protection channel traffic. A protection switch is effected by detecting a channel failure at the receive end of a span, transmitting a protection request on the return channel back to the transmit end of the span, and using this request in a controller for the channel to effect a protection switch, using an individual selector for the channel, if a priority scheme allows. The controllers are enabled or disabled under software control following a protection switch in accordance with the prevailing priority scheme. The arrangement provides for rapid protection switching.
    Type: Grant
    Filed: August 2, 1985
    Date of Patent: February 24, 1987
    Assignee: Northern Telecom Limited
    Inventors: David I. Reid, John C. Ellson, Malcolm C. Betts
  • Method and apparatus for code conversion of binary to multilevel signals
    Patent number: 4408189
    Abstract: A method and apparatus for converting a binary signal to one having quaternary-level symbols with no d-c component. To achieve this, the running digital sum is limited by selectively inverting words within each frame of (n) symbols. A separate (n+1)th symbol is added to each frame to indicate the selective inversion of the words, so that the correct polarity of the (n) symbols can be re-established.
    Type: Grant
    Filed: May 18, 1981
    Date of Patent: October 4, 1983
    Assignee: Northern Telecom Limited
    Inventors: Malcolm C. Betts, Alan F. Graves, Frederick M. Pascoe, James E. Dilley