Patents by Inventor Karl Tigerstedt
Karl Tigerstedt 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).
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Patent number: 7224976Abstract: There is provided a technique for determining cell allocation in a network supporting different communication standards.Type: GrantFiled: October 9, 2001Date of Patent: May 29, 2007Assignee: Nokia CorporationInventors: Atte Artamo, Karl Tigerstedt, Harri Holma, Uwe Schwarz, Kai Heikkinen, Achim Wacker
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Patent number: 7197318Abstract: The present invention relates to a method and apparatus for controlling a connection transfer in a cellular network having at least two systems, such as a GSM system and a WCDMA system. Based on a load determination, a service-based inter-system or inter-frequency handover of the connection to another system or to another carrier of the same system is initiated if the determined is below a threshold and service priorities are indicating it. If it exceeds the threshold, an additional load-based inter-system or inter-frequency handover can be initiated. If the load of the target cell is not known, a load estimation based on a learning process can be used to derive a probability of success of an interfrequency or inter-system handover, which may be used for deciding on the initiation of the inter-system handover. The learning process may be performed by evaluating preceding interfrequency or inter-system handovers to the target cell or preceding interfrequency or inter-system handovers from the target cell.Type: GrantFiled: April 26, 2001Date of Patent: March 27, 2007Assignee: Nokia CorporationInventors: Uwe Schwarz, Harri Holma, Karl Tigerstedt, Achim Wacker, Atte Artamo, Kai Heikkinen
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Patent number: 7085570Abstract: A handover method in a telecommunication system, the method comprising: clarifying whether a mobile station is in a dual coverage area, and, if the mobile station is in a dual coverage area, making the decision to make a handover from a cell of one radio system to a cell of another radio system and performing the handover.Type: GrantFiled: December 23, 2002Date of Patent: August 1, 2006Assignee: Nokia CorporationInventors: Karl Tigerstedt, Uwe Schwarz, Harri Holma, Atte Artamo, Pauli Aikio, Pekka J. Ranta, Terhi Rautiainen, Siamäk Naghian, Risto Aalto
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Patent number: 6836471Abstract: A method and system for inter-operator handover in a telecommunications network comprising a greenfield WCDMA operator and a GSM/WCDMA operator. When a mobile terminal of the greenfield operator is moving from the coverage area of the home network to the GSM/WCDMA area, a neighbor list of GSM cells is provided to the mobile terminal for handover to a GSM cell when the home network coverage is not available. When the mobile terminal is returning home from the GSM/WCDMA area, a neighbor list of the home cells is provided to the mobile terminal so that the greenfield mobile station is connected to its home network whenever there is coverage. Preferably, the neighbor lists are provided to the mobile terminal only in the connected mode.Type: GrantFiled: February 2, 2001Date of Patent: December 28, 2004Assignee: Nokia Mobile Phones Ltd.Inventors: Harri Holma, Karl Tigerstedt, Atte Artamo, Kai Heikkinen, Uwe Schwarz, Achim Wacker
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Publication number: 20040121777Abstract: The present invention relates to a method and apparatus for controlling a connection transfer in a cellular network having at least two systems, such as a GSM system and a WCDMA system. Based on a load determination, a service-based inter-system or inter-frequency handover of the connection to another system or to another carrier of the same system is initiated if the determined is below a threshold and service priorities are indicating it. If it exceeds the threshold, an additional load-based inter-system or inter-frequency handover can be initiated. If the load of the target cell is not known, a load estimation based on a learning process can be used to derive a probability of success of an interfrequency or inter-system handover, which may be used for deciding on the initiation of the inter-system handover. The learning process may be performed by evaluating preceding interfrequency or inter-system handovers to the target cell or preceding interfrequency or inter-system handovers from the target cell.Type: ApplicationFiled: October 24, 2003Publication date: June 24, 2004Inventors: Uwe Schwarz, Harri Holma, Karl Tigerstedt, Achim Wacker, Atte Artamo, Kai Heikkinen
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Publication number: 20040121770Abstract: A handover method in a telecommunication system, the method comprising: clarifying whether a mobile station is in a dual coverage area, and, if the mobile station is in a dual coverage area, making the decision to make a handover from a cell of one radio system to a cell of another radio system and performing the handover.Type: ApplicationFiled: December 23, 2002Publication date: June 24, 2004Inventors: Karl Tigerstedt, Uwe Schwarz, Harri Holma, Atte Artamo, Pauli Aikio, Pekka J. Ranta, Terhi Rautiainen, Siamak Naghian, Risto Aalto
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Publication number: 20040053606Abstract: There is provided a technique for determining cell allocation in a network supporting different communication standards.Type: ApplicationFiled: October 14, 2003Publication date: March 18, 2004Inventors: Atte Artamo, Karl Tigerstedt, Harri Holma, Uwe Schwarz, Kai Heikkinen, Achim Wacker
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Patent number: 6615044Abstract: A method of triggering an IF or IS handover between two WCDMA carrier or a WCDMA carrier and a GSM carrier. Six triggering conditions are used to initiate the search for an alternative network connection by starting the handover measurements. These triggering conditions are: a) the mobile terminal TxPwr has exceeded its threshold value longer than a specified time; b) the connection based power in the downlink has exceeded its threshold value longer than a specified time; c) the mobile terminal TxPwr has reached the maximum value a specified number of times; d) the SIR target at the base station has risen above a specified threshold value over a period of time; e) the mobile terminal TxPwr has exceeded its threshold value and the gradient of the power control signature indicates sudden rise to maximum power level; and f) the pilot power measured at the mobile terminal has fallen below a threshold value for long than a specified time.Type: GrantFiled: June 6, 2001Date of Patent: September 2, 2003Assignee: Nokia Mobile Phones, Ltd.Inventors: Karl Tigerstedt, Harri Holma, Kai Heikkinen, Atte Artamo, Uwe Schwarz, Achim Wacker
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Publication number: 20020187784Abstract: A method of triggering an IF or IS handover between two WCDMA carrier or a WCDMA carrier and a GSM carrier. Six triggering conditions are used to initiate the search for an alternative network connection by starting the handover measurements. These triggering conditions are: a) the mobile terminal TxPwr has exceeded its threshold value longer than a specified time; b) the connection based power in the downlink has exceeded its threshold value longer than a specified time; c) the mobile terminal TxPwr has reached the maximum value a specified number of times; d) the SIR target at the base station has risen above a specified threshold value over a period of time; e) the mobile terminal TxPwr has exceeded its threshold value and the gradient of the power control signature indicates sudden rise to maximum power level; and f) the pilot power measured at the mobile terminal has fallen below a threshold value for long than a specified time.Type: ApplicationFiled: June 6, 2001Publication date: December 12, 2002Applicant: Nokia Mobile Phones, Ltd.Inventors: Karl Tigerstedt, Harri Holma, Kai Heikkinen, Atte Artamo, Uwe Schwarz, Achim Wacker
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Publication number: 20020105927Abstract: A method and system for inter-operator handover in a telecommunications network comprising a greenfield WCDMA operator and a GSM/WCDMA operator. When a mobile terminal of the greenfield operator is moving from the coverage area of the home network to the GSM/WCDMA area, a neighbor list of GSM cells is provided to the mobile terminal for handover to a GSM cell when the home network coverage is not available. When the mobile terminal is returning home from the GSM/WCDMA area, a neighbor list of the home cells is provided to the mobile terminal so that the greenfield mobile station is connected to its home network whenever there is coverage. Preferably, the neighbor lists are provided to the mobile terminal only in the connected mode.Type: ApplicationFiled: February 2, 2001Publication date: August 8, 2002Applicant: Nokia Mobile Phones Ltd.Inventors: Harri Holma, Karl Tigerstedt, Atte Artamo, Kai Heikkinen, Uwe Schwarz, Achim Wacker