Patents by Inventor David J. Helmkamp

David J. Helmkamp 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: 5628052
    Abstract: Increased coverage and macro diversity from a single base station in a wireless communication system by having a base station coupled to N antennas is described. Increased coverage and macro diversity are achieved by transmitting from the base station N control messages each via one of the antennas, and transmitting a data message addressed to a mobile unit via a particular one of the antennas previously assigned to the mobile unit for an active call. The mobile unit receives the control messages and the data message and analyzes the control messages to identify from the antennas a best antenna. The mobile unit then transmits to the base station a new antenna request identifying the best antenna in an uplink control slot of a frame. The uplink control field is associated with the particular one of the antennas. The base station uses the best antenna to transmit subsequent data messages addressed to the mobile unit.
    Type: Grant
    Filed: September 12, 1994
    Date of Patent: May 6, 1997
    Assignee: Lucent Technologies Inc.
    Inventors: Charles M. DeSantis, David J. Helmkamp, Raymond A. Sackett
  • Patent number: 5265150
    Abstract: A wireless PBX system provides ease of installation without site engineering or trial-and-error placement of components within the system. In its basic form, the wireless PBX system consists of only two types of components: a control unit including an radio frequency transceiver; and fixed location terminals, such as telephones and voice/data stations, which also include radio frequency transceivers. Portable handsets are optionally included in the system to allow for customer mobility. Installation of the PBX system is achieved simply by placing the system components in the desired locations at a premises, plugging them into line power, and performing some simple programming steps including a final step of initiating an automatic configuring process. Through this process, the system automatically configures itself for optimum operation in view of the radio environment and placement of components within the system at the customer premises.
    Type: Grant
    Filed: January 30, 1991
    Date of Patent: November 23, 1993
    Assignee: AT&T Bell Laboratories
    Inventors: David J. Helmkamp, James W. Smith