Patents by Inventor Tomas Sandin

Tomas Sandin 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: 6341124
    Abstract: A plurality of base stations are operated in CDMA macrodiversity mode to communicate a message to a mobile station via an air interface. If the message is successfully communicated to one of the base stations via a packet network, the base station communicates the message to the mobile station via the air interface using CDMA. Otherwise, the base station refrains from communicating any message to the mobile station.
    Type: Grant
    Filed: March 13, 1998
    Date of Patent: January 22, 2002
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventors: Lars B. Johansson, Paul Peter Butovitsch, Tomas Sandin
  • Patent number: 6259927
    Abstract: Methods of controlling the power levels of transmitted signals in telecommunication systems are described. For example, a remote terminal measures the quality of a received signal, either by determining the frame error rate or the bit error rate, and reports its quality measurement to a network by sending a quality message. The network causes the signal transmitters to adjust their transmit power levels appropriately. Faster power control methods may be combined with slower power control methods for downlink (network to remote terminal) transmissions in various communications scenarios, such as soft hand-overs.
    Type: Grant
    Filed: June 6, 1997
    Date of Patent: July 10, 2001
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventors: Peter Butovitsch, Tomas Sandin, Magnus Persson
  • Patent number: 6067315
    Abstract: A method for power estimation in DS-CDMA schemes employing non-coherent detection is disclosed. By buffering channel complex amplitudes and, subsequent to non-coherent detection of a received symbol, coherently averaging the complex amplitudes retrieved, an accurate power estimate is achieved. By further estimating the Doppler frequency in an alternate embodiment, an even better estimate can be achieved. The amplitude of the channel can be regarded as constant over a longer time period than merely one symbol and the coherent averaging generates more accurate power estimates than that achieved by non-coherent averaging. By estimating the Doppler frequency and only averaging coherently over a period no longer than the coherence time an even better estimate is achieved. The variance of the estimates is decreased and the effect of biasing is increasingly limited.
    Type: Grant
    Filed: December 4, 1997
    Date of Patent: May 23, 2000
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventor: Tomas Sandin
  • Patent number: 5946357
    Abstract: Apparatus and associated method for improving the radio link performance of a radio communication system, such as a cellular communication system. Multi-stage encoding and interleaving of the data bits of a digital information signal is performed at a single logical device, such as a radio base station. By performing two stages of interleaving over the same number of information frames of the data bits, only a single buffering stage is required to perform such multi-stage interleaving.
    Type: Grant
    Filed: January 17, 1997
    Date of Patent: August 31, 1999
    Assignee: Telefonaktiebolaget L M Ericsson
    Inventors: Tomas Sandin, Paul Teder, H.ang.kan Persson