Patents by Inventor Christiaan Roobol

Christiaan Roobol 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: 6947394
    Abstract: A flexible Radio Link Control (RLC) protocol for a mobile communication system is provided, whereby a plurality of different RLC functions are defined. These different RLC functions can be combined in a number of different ways to produce a complete and functional, but more flexible RLC protocol than the existing protocol. For example, a new set of rules are provided for determining how and/or when to poll for, or send, a status report for Automatic Repeat Request (ARQ) purposes. As such, for a specific service configuration, one set of the rules can be used, and for a different service configuration, another set of the rules can be used. In this way, the rules can be conformed suitably to the type of service involved.
    Type: Grant
    Filed: April 6, 2000
    Date of Patent: September 20, 2005
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Mathias Johansson, Per Beming, Christiaan Roobol, Bela Rathonyi, Joachim Sachs, Michael Meyer, Roger Kalden
  • Patent number: 6772215
    Abstract: A method for minimizing feedback responses in an ARQ protocol is disclosed, whereby different mechanisms can be used to indicate erroneous D-PDUs and construct S-PDUs. The S-PDUs are constructed so as to optimize performance in accordance with certain criteria. One such criterion used is to minimize the size of the S-PDUs. A second such criterion used is to maximize the number of SNs included in an S-PDU of limited size.
    Type: Grant
    Filed: March 29, 2000
    Date of Patent: August 3, 2004
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Bela Rathonyi, Joachim Sachs, Michael Meyer, Per Beming, Mathias Johansson, Christiaan Roobol, Erik Schön, Kazuhiko Inoue
  • Patent number: 6643813
    Abstract: The reliability of data communication by is improved analyzing plural data units in a group or a block rather than analyzing individual data units. For example, at the time that a transmitter desires or needs to send a polling request to a receiver, there may be more than one data unit available for delivery as a group. The polling fields of all the data units in this group are set to indicate a poll request. When the receiver receives this group of data units, it sends the requested status information to the transmitter if the polling field of at least one of the received data units in the group indicates a poll request. Moreover, the receiver sends the requested status information only once. Those other polling fields may be used to increase the reliability of the transmission.
    Type: Grant
    Filed: February 17, 1999
    Date of Patent: November 4, 2003
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Mathias Johansson, Christiaan Roobol, Johan Larsson
  • Patent number: 6597675
    Abstract: A method is disclosed for processing mobile-originated random access requests in a mobile telecommunications system that randomly selects new signatures for re-transmissions in the event that collisions have occurred. As such, the random access re-transmissions are randomized over the signature domain instead of just over the time domain. Consequently, the disclosed invention significantly shortens random access delays caused by collisions or erroneous arrivals at base station receivers, and also significantly reduces the interval between random access re-transmissions.
    Type: Grant
    Filed: September 4, 1998
    Date of Patent: July 22, 2003
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Riaz Esmailzadeh, Karim Jamal, Christiaan Roobol
  • Patent number: 6363058
    Abstract: A method for processing multiple data services over a communications link between a mobile station and a base station is disclosed. A RLC/MAC protocol layer of the communications link between a mobile station and a base station receives a plurality of radio bearer services each including at least one service provided by the mobile station. The plurality of radio bearer services are processed in such a manner that services having substantially similar quantity of signal requirements are combined for transmission on a single logical channel. Data within the transmission blocks may be prioritized to enable flexible control of transmission rates.
    Type: Grant
    Filed: April 15, 1998
    Date of Patent: March 26, 2002
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Christiaan Roobol, Johan Lundsjö, Mathias Johansson, Per Beming
  • Patent number: 6307867
    Abstract: An optimal data block size is determined for use in transmitting data at variable rates over a communications link in predetermined time intervals, where each predetermined time interval has the same time duration. Rather than varying data block size according to changes in transmission rates, which adds unnecessary complexity, the data blocks all have the same fixed size, i.e., the same number of data bits in each block. That fixed data block size is determined so that for all of the available data transmission rates, each predetermined time interval is fully occupied with useful information. The fixed data block size is determined based on a maximum frequency at which the transmission rate may change on the communications link and a lowest available transmission rate.
    Type: Grant
    Filed: May 14, 1998
    Date of Patent: October 23, 2001
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Christiaan Roobol, Mathias Johansson, Johan Lundsjö, Per Beming
  • Patent number: 6301479
    Abstract: A technique for providing a secure link when transitioning between pairs of link layer protocol entities in a mobile communication system is disclosed. The first pair of link layer protocol entities includes a first transmitting link layer protocol entity and a first receiving link layer protocol entity. The second pair of link layer protocol entities includes a second transmitting link layer protocol entity and a second receiving link layer protocol entity. The technique is realized by first suspending data transmissions from the first transmitting link layer protocol entity to the first receiving link layer protocol entity, and then initiating data transmissions from the second transmitting link layer protocol entity to the second receiving link layer protocol entity.
    Type: Grant
    Filed: July 8, 1999
    Date of Patent: October 9, 2001
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventors: Christiaan Roobol, Mathias Johansson, Raul Söderstrom, Bela Rathonyi, Joachim Sachs
  • Patent number: 6236646
    Abstract: In a spread spectrum communications system supporting bursty uplink and downlink data packet transmission telecommunications services, significant concerns exist as to the generation of unacceptable levels of interference resulting from plural and simultaneous data packet transmissions. To address this concern, the system selectively organizes an access schedule for mobile station uplink data packet transmissions and a delivery schedule for downlink data packet transmissions. For the uplink, the schedule is transmitted to plural mobile stations in a current frame, and identifies which one or ones of plural mobile stations are authorized to make an uplink data packet transmission in a next frame. Only those mobile stations scheduled with authorization to make an access in the next frame then transmit their data packets (or a portions thereof) to the base station during that next frame. On the downlink, a notification of intended delivery is communicated to destination mobile stations in a current frame.
    Type: Grant
    Filed: September 9, 1997
    Date of Patent: May 22, 2001
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Per Beming, Mathias Johansson, Johan Lundsjö, Christiaan Roobol