Patents by Inventor Torbjorn Ward

Torbjorn Ward 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: 6330450
    Abstract: A system and method for minimizing effects of both internal and external transmitter noise in order to improve control decisions that are based on signal strength measurements. A wireless network includes an internal transmitter transmitting a first signal at a first frequency and noise at other frequencies in a known pattern. The signal strength of the first signal is measured by the receiver at the first frequency. The noise of the transmitter of the first signal is calculated on other frequencies, using the first transmitter's known noise pattern. A determination is then made whether the noise of the first signal is above a threshold on one or more of the other frequencies used by the wireless communication system. If the noise is above the threshold, corrective action is taken. The wireless network further includes one or more receivers that measure signal strengths on the range of frequencies used by the system.
    Type: Grant
    Filed: January 25, 1999
    Date of Patent: December 11, 2001
    Assignee: Ericsson, Inc.
    Inventors: Kenneth Wallstedt, Torbjorn Ward
  • Patent number: 6006092
    Abstract: Each base station in a cellular telephone system includes a signal strength measurement device operable to tune to and make signal strength measurements on not only the voice channels assigned to other cells, but also on its own voice channels. The measurements on the own voice channels provide an indication of injected interference useful in making quality driven voice channel assignments during either call set-up or hand-off. In a conventional analog cellular system, the signal strength measurement device comprises the base station signal strength receiver measuring on own idle base station analog voice frequencies. In a time division multiple access (TDMA) cellular system, the signal strength measurement device comprises the base station location verification module measuring during idle time slots on digital voice frequencies.
    Type: Grant
    Filed: February 22, 1996
    Date of Patent: December 21, 1999
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventor: Torbjorn Ward
  • Patent number: 5974320
    Abstract: A neighborhood zone covering an enclosed or surrounded environment, such as a man-made building or high-rise, is defined within a mobile telecommunications network by associating a plurality of base stations with respective cell areas. A same neighborhood list indicating all measurement channels being utilized within the neighborhood zone by said plurality of base stations is then further defined. The defined same neighborhood list is then transmitted by each of the base stations within its respective coverage area. A mobile station traveling within the neighborhood zone then scans and reports measurements from the indicated measurement channels to the serving mobile telecommunications network. The mobile telecommunications network then effectuates a handover in accordance with the received signal measurements. An idle mobile station further utilizes the measurements to effectuate a cell re-selection.
    Type: Grant
    Filed: May 21, 1997
    Date of Patent: October 26, 1999
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Torbjorn Ward, Anders Sandell, Daniel Dufour
  • Patent number: 5701294
    Abstract: A system and method for dynamically adapting the user bit rate of a time division multiple access (TDMA) cellular telecommunication system to achieve optimum voice quality over a broad range of radio channel conditions are disclosed. The system continuously monitors radio channel quality on both the uplink and the downlink, and dynamically adapts the system's combination of speech coding, channel coding, modulation, and number of assignable time slots per call to optimize voice quality for the measured conditions. Various combinations of the system's speech coding, channel coding, modulation, and assignable time slots are identified as combination types and corresponding cost functions are defined. By identifying and selecting the cost function with the lowest cost for the measured radio channel conditions, the system provides the maximum voice quality achievable within the limits of the system design.
    Type: Grant
    Filed: October 2, 1995
    Date of Patent: December 23, 1997
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventors: Torbjorn Ward, Anders Sandell
  • Patent number: 5663958
    Abstract: The time division multiple access (TDMA) frame time synchronization error for received mobile station burst communications transmitted on the reverse digital control channel is monitored by the receiving base station. A probability density function is then prepared by the base station reflecting the number of instances of each determined length of time synchronization error monitored over a predetermined time period. The probability density function is then processed to identify the percentage of burst communications during that predetermined time period that exceed a synchronization error threshold. If the determined percentage exceeds a given percentage, then abbreviated length burst communication operating mode is ordered by the base station for all mobile stations operating within the cell. Otherwise, conventional length burst communication operating mode is ordered by the base station.
    Type: Grant
    Filed: February 22, 1996
    Date of Patent: September 2, 1997
    Assignee: Telefonaktiebolaget Lm Ericsson
    Inventor: Torbjorn Ward
  • Patent number: 5542097
    Abstract: A digital radiocommunication system and method for providing a consistency check to confirm the identity of a candidate cell for handoff of a digital traffic channel are described. Using relative pathloss comparisons reliance on absolute measurements which can lead to inappropriate handoffs for a variety of reasons. Statistical measurements can also be used to further reduce errors.
    Type: Grant
    Filed: February 22, 1995
    Date of Patent: July 30, 1996
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventors: Torbjorn Ward, Norio Iizuka
  • Patent number: 5448762
    Abstract: In a mobile radio communications station, a communications reception frequency is generated and a time sequence of a plurality of reception monitoring frequencies is separately generated. A reception frequency is switched between the communications reception frequency during a communications reception and a current one of the monitoring reception frequencies during a monitoring reception. More particularly, separate frequency synthesizers are provided for communications reception on the one hand and signal strength monitoring on the other hand. The frequency of the synthesizer for communications reception remains fixed during the course of a communication. The synthesizer for signal strength monitoring need not be as accurate as that for communications reception. Furthermore, since the synthesizer is used only for signal strength monitoring instead of for both communications reception and signal strength monitoring, more time is available for switching between frequencies.
    Type: Grant
    Filed: December 1, 1993
    Date of Patent: September 5, 1995
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventor: Torbjorn Ward
  • Patent number: 5297169
    Abstract: Reception of a transmission in a radiotelephone system including an equalizer is improved by training the equalizer using a synchronization portion of the transmission having a data pattern chosen for its correlation properties and retraining the equalizer using a portion of the transmission transmitted for a different purpose. In particular, the portion of the transmission transmitted for a different purpose may be the digital verification color code transmitted during each burst in a digital cellular mobile radiotelephone system. Reception quality is increased by training the equalizer at more frequent intervals without increasing transmission overhead.
    Type: Grant
    Filed: June 28, 1991
    Date of Patent: March 22, 1994
    Assignee: Telefonaktiebolaget L M Ericsson
    Inventors: Tomas Backstrom, Torbjorn Ward, Gustav Larsson