Patents by Inventor Charles Y. Farwell

Charles Y. Farwell 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: 5491741
    Abstract: Base stations responding on a shared channel to a registration request message received on another shared channel from a wireless mobile unit with the base station to which the mobile unit is assigned transmitting in a first time slot and the other base stations transmitting in a time slot determined by the strength of the received signal from the mobile unit. If two base stations respond to the registration request message in the same time slot and the assigned base station does not respond, the mobile unit determines whether there is a response in a time slot which is earlier in time to the first time slot than the collided time slot. If the collided time slot is earlier in time than any other time slot in which a response is received, the mobile unit transmits a second registration request message specifying the collided time slot.
    Type: Grant
    Filed: October 23, 1992
    Date of Patent: February 13, 1996
    Assignee: AT&T Corp.
    Inventors: Charles Y. Farwell, Richard D. Miller, Richard A. Windhausen
  • Patent number: 5444766
    Abstract: An arrangement for effecting call handoffs in a wireless communications system (FIG. 1 ) in a substantially glitchless manner. The arrangement relies on the mobile terminal (4) that is involved in a handoff to trigger the handoff by transmitting a handoff coordination signal simultaneously to the base stations (1, 2) that are involved in the handoff. The base stations receive the signal substantially simultaneously, and in response the base station that has been serving the mobile terminal's call ceases to do so while the base station that is henceforth to serve the mobile terminal's call commences to do so at the same instant in time.
    Type: Grant
    Filed: October 1, 1993
    Date of Patent: August 22, 1995
    Assignee: AT&T Corp.
    Inventors: Charles Y. Farwell, Richard D. Miller, Richard A. Windhausen
  • Patent number: 5396541
    Abstract: Signaling a mobile unit to transmit a synchronization pattern with voice information upon detecting from the signal strength of the wireless mobile unit by a base station that the mobile unit is approaching a minimum threshold. Where the voice information is initially being transmitted in a set of frequency hopping channels using spread spectrum transmission, the synchronization pattern is transmitted in one or more of the set of frequency hopping channels. In addition, the base station alerts a system controller to this fact, and the system controller requests that neighboring base stations monitor the set of frequency hopping channels being transmitted by the mobile unit. In order to synchronize to the mobile unit, the base stations utilize the synchronization pattern to come into synchronization with the mobile unit. The system controller transfers the wireless mobile unit to the base station which is receiving the strongest signal strength.
    Type: Grant
    Filed: October 23, 1992
    Date of Patent: March 7, 1995
    Assignee: AT&T Corp.
    Inventors: Charles Y. Farwell, Richard D. Miller, Richard A. Windhausen
  • Patent number: 5305308
    Abstract: A wireless-access communications system, such as a CDMA cellular radio-telephone system (FIG. 2), comprises a packet-switched communications network (202, 207, 201) that interconnects cells (base stations; 202) with each other and with the public telephone network (100). Traffic of individual calls is packetized, and packet-bearing frames (300 in FIG. 7) of a plurality of calls are then statistically multiplexed and frame-relayed through the network to yield the high capacity, efficiency, and speed of traffic transport and handoff required for a CDMA cellular system. At each call processing unit (264 in FIG. 5), individual calls are handled by individual service circuits (602 & 612) which perform speech-processing functions such as coding and decoding, tone insertion, and echo cancellation, and packet-to-circuit-switched-PCM traffic conversion.
    Type: Grant
    Filed: October 29, 1992
    Date of Patent: April 19, 1994
    Assignee: AT&T Bell Laboratories
    Inventors: Michael J. English, Charles Y. Farwell, Michael L. Hearn, Richard M. Heidebrecht, David M. Kissel, Paul E. Miller, Richard D. Miller, Alan S. Mulberg, Michael A. Smith, Douglas A. Spencer, John S. Thompson, Richard A. Windhausen
  • Patent number: 5195091
    Abstract: A CDMA cellular radio-telephone system (FIG. 2) has switching systems (201) synchronized to public telephone network (100) timing signals (600), and radio telephones (203) and cell base stations (202) synchronized to a different clock (1000). Transmission delays between the cell base stations and the telephone network are variable. Switching systems include digital communications interfaces (264) to the telephone system, whose connections to the telephone system are synchronized to the telephone system, and whose connections to the cells are nominally also synchronized to the telephone system but whose processor (602) operates for each call within predefined windows (1302, 1402) of phase relationships to the operation of the cell that is handling the call, and occasionally adjusts (FIGS. 13-16) its phase relationships to the operation of the telephone system to achieve and maintain its operation within the predefined windows.
    Type: Grant
    Filed: July 9, 1991
    Date of Patent: March 16, 1993
    Assignee: AT&T Bell Laboratories
    Inventors: Charles Y. Farwell, Michel L. Hearn, Richard M. Heidebrecht, Kelvin K. Ho, Douglas A. Spencer
  • Patent number: 5195090
    Abstract: A wireless-access communications system, such as a CDMA cellular radio-telephone system (FIG. 2), comprises a packet-switched communications network (202, 207, 201) that interconnects cells (base stations; 202) with each other and with the public telephone network (100). Traffic of individual calls is packetized, and packet-bearing frames (300 in FIG. 7) of a plurality of calls are then statistically multiplexed and frame-relayed through the network to yield the high capacity, efficiency, and speed of traffic transport and handoff required for a CDMA cellular system. At each call processing unit (264 in FIG. 5), individual calls are handled by individual service circuits (602 and 612) which perform speech-processing functions such as coding and decoding, tone insertion, and echo cancellation, and packet-to-circuit-switched-PCM traffic conversion.
    Type: Grant
    Filed: July 9, 1991
    Date of Patent: March 16, 1993
    Assignee: AT&T Bell Laboratories
    Inventors: Brian D. Bolliger, Talmage P. Bursh, Jr., Marc K. Dennison, Michael J. English, Charles Y. Farwell, Michel L. Hearn, Richard M. Heidebrecht, Kelvin K. Ho, Kenneth Y. Ho, David M. Kissel, Paul E. Miller, Richard D. Miller, Alan S. Mulberg, LaJeana N. Roberts, Michael A. Smith, Kenneth F. Smolik, Douglas A. Spencer, Kenneth W. Strom, John S. Thompson, Richard A. Windhausen
  • Patent number: 5184347
    Abstract: A CDMA cellular radio-telephone system (FIG. 2) has switching systems (201) synchronized to public telephone network (100) timing signals (600), and radio telephones (203) and cell base stations (202) synchronized to different clock (1000). Transmission delays between the cell base stations and the telephone network are variable. Switching systems include digital communications interfaces (264) to the telephone system, whose connections to the telephone system are synchronized to the telephone system, and whose connections to the cells are nominally also synchronized to the telephone system but whose processor (602) operates for each call within predefined windows (1302, 1402) of phase relationships to the operation of the cell that is handling the call, and occasionally adjusts (FIGS. 13-16) its phase relationships to the operation of the telephone system to achieve and maintain its operation within the predefined windows.
    Type: Grant
    Filed: July 9, 1991
    Date of Patent: February 2, 1993
    Assignee: AT&T Bell Laboratories
    Inventors: Charles Y. Farwell, Michel L. Hearn, Richard M. Heidebrecht, Kelvin K. Ho, Douglas A. Spencer