Patents by Inventor Jacobus Haartsen

Jacobus Haartsen 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: 6028853
    Abstract: The present invention relates to a method and arrangement in an ad-hoc network for synchronizing a multiple of radio transceiver arrangements with different characteristics that make use of a common air interface. Each transceiver arrangement comprises at least two transceivers which mutually communicate via a radio transmission link. All transceivers synchronize to a common synchronization signal comprising two staggered beacon pulse series signals (TX.sub.1, TX.sub.2) which have the same repetition rate. The transceivers synchronize their internal timers which control the signal transmission from the transceivers, to the strongest one of the two beacon pulse series signals (TX.sub.1, TX.sub.2) by listening during one of the corresponding sets of time windows (RX.sub.1, RX.sub.2). Between the reception of two beacon pulses, each transceiver transmits beacon pulses itself, thus contributing to the generation of the other beacon pulse series signal, on which other transceivers can lock.
    Type: Grant
    Filed: June 6, 1997
    Date of Patent: February 22, 2000
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventor: Jacobus Haartsen
  • Patent number: 5842037
    Abstract: A method for suppressing interference in an integrated communication/computing device is disclosed. First, an interrupt signal is sent from a transceiver to a computing device when the transceiver is about to transmit or receive information. In response to the interrupt signal, the computing device stacks current status and enters an interrupt routine. The computing device is then released from the interrupt routine after the information has been transmitted or received.
    Type: Grant
    Filed: March 20, 1995
    Date of Patent: November 24, 1998
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventor: Jacobus Haartsen
  • Patent number: 5699367
    Abstract: A retransmission method is disclosed wherein retransmissions over the sensitive link of the connection only involves packets that were actually disturbed in the sensitive link. At the same time, required storage capacity in the relay stations connecting the sensitive link to the nonsensitive link is reduced. Errors occurring in the sensitive part of the connection will cause retransmission over nonsensitive links of the connection as well, but this is considered to be of less importance since the nonsensitive links have a high throughput and/or low costs.
    Type: Grant
    Filed: December 29, 1995
    Date of Patent: December 16, 1997
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventor: Jacobus Haartsen
  • Patent number: 5568096
    Abstract: An apparatus and method are provided for increasing the effective Q-value of an oscillator so that the required Q-value can be reached with the use of a low Q-value oscillator. In this apparatus and method, the FM noise is measured at the output of the oscillator by an FM detector and the output of the FM detector is fed back to the control input of the oscillator. By using this negative FM feedback, frequency variations in the oscillator output are suppressed by applying a correction signal at the control input of the oscillator. The amount of suppression depends on the loop gain of the FM feedback loop and the amount of suppression is proportional to the loop gain so that the effective Q-value of the oscillator is proportional to the loop gain.
    Type: Grant
    Filed: April 19, 1995
    Date of Patent: October 22, 1996
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventor: Jacobus Haartsen
  • Patent number: 5561399
    Abstract: An apparatus and method are provided for increasing the Q-value of an oscillator so that a net gain in the stability of the oscillators is obtained. In the apparatus and method, a plurality of units, which each include a passive frequency-selective circuit and an active amplifier, are cascaded and the required isolation between the passive frequency-selective circuits is maintained by the active amplifier acting as a buffer. As a result, interaction and loading is prevented between the passive frequency-selective circuits so that the net gain in the stability of the oscillator is achieved because the Q-value of the oscillator is increased.
    Type: Grant
    Filed: April 19, 1995
    Date of Patent: October 1, 1996
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventor: Jacobus Haartsen