Patents by Inventor Shavantha Kularatna

Shavantha Kularatna 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: 9054652
    Abstract: Enhancing the intermodulation performance of an RF power amplifier by determining a coarse time delay represented by an integer T1; determining a reference point for a transmitted signal waveform of the RF power amplifier; shifting the waveform by a set of offsets comprising a plurality of non-integer fractional steps from (T1?Xd) to (T1+Xd) where T1 is the integer and Xd is a non-integer fractional step size value for defining fractional steps about the integer T1 such that the non-integer fractional steps progress in a positive direction as well as a negative direction; correlating the transmitted signal waveform with a feedback signal waveform to obtain a respective correlation value for each of corresponding fractional steps; obtaining an accurate fractional delay value by selecting a fractional step having a highest respective correlation value; applying the obtained correct fractional delay value to the transmitted signal waveform to provide a compensated transmitted signal waveform, and combining the c
    Type: Grant
    Filed: October 2, 2013
    Date of Patent: June 9, 2015
    Assignee: Nokia Solutions and Networks Oy
    Inventors: Shavantha Kularatna, Christian Reichl, Bjoern Jelonnek, Glenn Schedeen, Sandeep Mehta
  • Publication number: 20150091643
    Abstract: Enhancing the intermodulation performance of an RF power amplifier by determining a coarse time delay represented by an integer T1; determining a reference point for a transmitted signal waveform of the RF power amplifier; shifting the waveform by a set of offsets comprising a plurality of non-integer fractional steps from (T1?Xd) to (T1+Xd) where T1 is the integer and Xd is a non-integer fractional step size value for defining fractional steps about the integer T1 such that the non-integer fractional steps progress in a positive direction as well as a negative direction; correlating the transmitted signal waveform with a feedback signal waveform to obtain a respective correlation value for each of corresponding fractional steps; obtaining an accurate fractional delay value by selecting a fractional step having a highest respective correlation value; applying the obtained correct fractional delay value to the transmitted signal waveform to provide a compensated transmitted signal waveform, and combining the c
    Type: Application
    Filed: October 2, 2013
    Publication date: April 2, 2015
    Applicant: Nokia Solutions and Networks Oy
    Inventors: Shavantha Kularatna, Christian Reichl, Bjoern Jelonnek, Glenn Schedeen, Sandeep Mehta
  • Patent number: 7307968
    Abstract: The method and system provides a data packet encapsulated with protocol data according to an embodiment of the invention. A data packet for communication may be associated with a TLLI and a NSAPI identifying a communications path between a BSS and a SGSN. The method and system provides a BVC associated with the BSS and the SGSN and a NSE that provides communication service to the BVC over NS-VC. The BVC, NSE and NS-VC may be associated with the TLLI and NSAPI. The encapsulated protocol data comprises UDP and IP. UDP provides UDP ports associated with NS-VC. The UDP ports identified as data designated as either real time or non-real time services. IP provides an IP address identifying the NSE providing service to the BVC. The data packet encapsulated with UDP and IP provides for more efficient, flexible and reliable communications between a BSS and a SGSN.
    Type: Grant
    Filed: February 16, 2001
    Date of Patent: December 11, 2007
    Assignee: Nokia Corporation
    Inventors: Tuomas Niemela, Shkumbin Hamiti, Risto Mononen, Shavantha Kularatna
  • Patent number: 7215958
    Abstract: The present invention relates to a relocation method, system and network element for changing a serving radio resource control entity After an initial operating state in which a user equipment (30) has radio links with a serving network element (20) and a drift network element (21) supporting said serving network element (20) with a wireless connection, the serving network element (20) transmits a relocation-specific information to a target network element (22). Based on the relocation-specific information, the target network element (22) establishes a link to the drift network element (21), such that the drift network element (21) can receive user traffic from both the serving network element (20) and the target network element (20). Then, the radio resource control is relocated to the target network element (20). The relocation-specific information may comprise an identifier or a list of identifiers of drift network elements.
    Type: Grant
    Filed: August 20, 2001
    Date of Patent: May 8, 2007
    Assignee: Nokia Corporation
    Inventors: Andras Kovacs, Shavantha Kularatna, Atte Länsisalmi, Gabriel Ramos, Syed Hossain, Pekka Korja, Raquel Sanchez, Sanna Mäenpää
  • Patent number: 7035213
    Abstract: The invention is a method of determining in at least one communication network if a session should be established in at least one communication network containing a plurality of session established entities, a method for determining if a session should be established with caller user equipment requesting the session, and in at least one communication network, a method for determining if a session should be established from caller user equipment at at least one communication network.
    Type: Grant
    Filed: October 30, 2002
    Date of Patent: April 25, 2006
    Assignee: Nokia Corporation
    Inventors: Timothy L. Moran, Markus Isomäki, Sreenivas Addagatla, Kaiser Chen, Shavantha Kularatna, Basavarai Patil
  • Patent number: 6944146
    Abstract: A method and apparatus for use in a mobile communications system having a plurality of cell segments includes allocating a plurality of channels to perform communications and defining a plurality of time groups. A channel reuse pattern is provided that is based on the plurality of channel frequencies and the plurality of time groups. Control channels are carried in a different time slot of a frame in each time group. Predetermined time slots are allocated as guard periods to reduce likelihood of interference of signaling due to overlap of time slots in neighboring cell segments. In one arrangement, three channel frequencies are allocated. Further, three or four time groups are defined to provide an effective 3/9 or 4/12 channel reuse pattern. In each time group, control channels are carried in odd time slots of a time-division multiple access (TDMA) frame.
    Type: Grant
    Filed: August 4, 1999
    Date of Patent: September 13, 2005
    Assignee: Nortel Networks Limited
    Inventors: Peter A. Barany, Shavantha Kularatna, Eric N. Johnson, Shamim Akbar Rahman
  • Patent number: 6904034
    Abstract: The invention provides a method and system for allowing communication between a BSS and SGSN, each having an NS-VC table and utilizing a different mode of communication. For example, a BSS may utilize associating UDP with NSE and IP with NS-VC and the SGSN may utilize associating UDP with NS-VC and IP with NSE. The method and system provides for the construction of an NS-VC table correlating the NS-VC table of the BSS and SGSN. Therefore, the method and system provides for the conversion of a data packet having UDP associated with NS-VC and IP associated with NSE to UDP having association with NSE and IP having association with NS-VC and vice versa. An NS-VC table may be constructed from information provided from a negotiations procedure or normal communications. The constructed NS-VC table allows for communications between the mobile communications architecture and the packet switched architecture, without requiring compatible utilization of UDP and IP.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: June 7, 2005
    Assignee: Nokia Corporation
    Inventors: Shavantha Kularatna, Shkumbin Hamiti, Tuomas Niemela, Basavaraj Patil, Rayadurgam Ravikanth
  • Patent number: 6771962
    Abstract: Apparatus, and an associated method, for a mobile communication system in which handovers of communications are effectuated between access points of the communication system as a mobile node travels there through. A manner is provided by which to perform handover evaluation functions more efficiently by performing at least some of the handover evaluations at the access point to which a mobile node is attached. And, a manner is provided by which to provide care-of-addresses formed of temporary identifiers to temporarily identify a mobile node to permit the routing of packet data thereto during a communication session.
    Type: Grant
    Filed: March 30, 2001
    Date of Patent: August 3, 2004
    Assignee: Nokia Corporation
    Inventors: Yousuf Saifullah, Basavaraj Patil, Shavantha Kularatna, Rene Purnadi, Stefano Faccin
  • Patent number: 6711406
    Abstract: Apparatus, and an associated method, facilitates changeover of mode of operation of a mobile station operable in a cellular communication system. Changeover of the mode of operation of the mobile station is required when the mobile station is operated in the packet mode and a circuit-switched call is to be terminated at the mobile station. A page is transmitted to the mobile station which includes an allocation of time during which a response to a page forming a request to suspend the packet mode of operation is to be generated.
    Type: Grant
    Filed: May 3, 2000
    Date of Patent: March 23, 2004
    Assignee: Nokia Corporation
    Inventors: Raino Lintulampi, Kari Jyrkkä, Heikki Päivike, Shavantha Kularatna, Pekka Mottonen
  • Publication number: 20030229699
    Abstract: A method of limiting the media description negotiation in Mobile IP networks, comprising the steps of: filtering, by a proxy call state control means (P-CSCF), a media description list of a user equipment (UE; UE-O, UE-T) based on policy constraints of networks which are involved in a communication connection of said user equipment (UE; UE-O, UE-T); and establishing a communication connection of said user equipment (UE; UE-O, UE-T), wherein a media description list for said communication connection is negotiated by said proxy call state control means (P-CSCF).
    Type: Application
    Filed: June 7, 2002
    Publication date: December 11, 2003
    Inventors: Timothy L. Moran, Kaiser Chen, Sreenivas Addagatla, Shavantha Kularatna, Basavaraj Patil
  • Patent number: 6594252
    Abstract: A mobile communications system includes a first link and a second link (e.g., a circuit-switched link and a packet-switched link). When a mobile unit is initialized in the mobile communications system, it identifies a first control signal, such as the digital control channel (DCCH) of an IS-136 system, of the first link. From information associated with the first control signal, the mobile unit determines the existence of the second link (e.g., according to 136 HS). From information identifying a current frame structure in the first link, a pointer to the current frame structure of the second link can be derived.
    Type: Grant
    Filed: August 4, 1999
    Date of Patent: July 15, 2003
    Assignee: Nortel Networks Limited
    Inventors: Peter A. Barany, Shavantha Kularatna, Shamim Akbar Rahman
  • Publication number: 20030103457
    Abstract: The invention is a method of determining in at least one communication network if a session should be established in at least one communication network containing a plurality of session established entities, a method for determining if a session should be established with caller user equipment requesting the session, and in at least one communication network, a method for determining if a session should be established from caller user equipment at at least one communication network.
    Type: Application
    Filed: October 30, 2002
    Publication date: June 5, 2003
    Inventors: Timothy L. Moran, Markus Isomaki, Sreenivas Addagatla, Kaiser Chen, Shavantha Kularatna, Basavarai Patil
  • Publication number: 20030036387
    Abstract: The present invention relates to a relocation method, system and network element for changing a serving radio resource control entity After an initial operating state in which a user equipment (30) has radio links with a serving network element (20) and a drift network element (21) supporting said serving network element (20) with a wireless connection, the serving network element (20) transmits a relocation-specific information to a target network element (22). Based on the relocation-specific information, the target network element (22) establishes a link to the drift network element (21), such that the drift network element (21) can receive user traffic from both the serving network element (20) and the target network element (20). Then, the radio resource control is relocated to the target network element (20). The relocation-specific information may comprise an identifier or a list of identifiers of drift network elements.
    Type: Application
    Filed: August 20, 2001
    Publication date: February 20, 2003
    Inventors: Andras Kovacs, Shavantha Kularatna, Atte Lansisalmi, Gabriel Ramos, Syed Hossain, Pekka Korja, Raquel Sanchez, Sanna Maenpaa
  • Publication number: 20030002455
    Abstract: The invention provides a method and system for allowing communication between a BSS and SGSN, each having an NS-VC table and utilizing a different mode of communication. For example, a BSS may utilize associating UDP with NSE and IP with NS-VC and the SGSN may utilize associating UDP with NS-VC and IP with NSE. The method and system provides for the construction of an NS-VC table correlating the NS-VC table of the BSS and SGSN. Therefore, the method and system provides for the conversion of a data packet having UDP associated with NS-VC and IP associated with NSE to UDP having association with NSE and IP having association with NS-VC and vice versa. An NS-VC table may be constructed from information provided from a negotiations procedure or normal communications. The constructed NS-VC table allows for communications between the mobile communications architecture and the packet switched architecture, without requiring compatible utilization of UDP and IP.
    Type: Application
    Filed: June 29, 2001
    Publication date: January 2, 2003
    Inventors: Shavantha Kularatna, Shkumbin Hamiti, Tuomas Niemela, Basavaraj Patil, Rayadurgam Ravikanth
  • Patent number: 6497599
    Abstract: A mobile communications system having a plurality of cells, with each cell being divided into a number of sectors. Each sector is allocated one of a corresponding number of channels of different frequencies. In addition, a plurality of time groups are defined, and a channel reuse pattern is provided that is based on both channel frequencies and time groups. In one arrangement, a 1/3 channel reuse pattern is provided to carry traffic signals in the system. For control signals, which are more susceptible to interference, a higher effective channel reuse pattern (e.g., 3/9 or 4/12) based on both frequency and time is employed.
    Type: Grant
    Filed: August 4, 1999
    Date of Patent: December 24, 2002
    Assignee: Nortel Networks Limited
    Inventors: Eric N. Johnson, Adrien A. Comeau, Peter A. Barany, Shavantha Kularatna
  • Patent number: 6463073
    Abstract: The invention is a novel slot structure and method of transmitting data at a controllable power level. The slot comprises a header, a DATA field adjacent the header and a ramp interval adjacent the DATA field. The method consists of transmitting the entire slot at a sufficiently high power when the DATA field is occupied by data traffic or control information but to lower the power during transmission of the DATA field when the slot is a null slot. In the latter case, a gradual decrease of the transmitted power is effected during the first few symbols of the DATA field, whereas the power is brought back to a higher level during the ramp interval. The new power level may be higher or lower than the initial power level, depending on the destination mobile unit associated with the following slot.
    Type: Grant
    Filed: December 21, 1998
    Date of Patent: October 8, 2002
    Assignee: Nortel Networks Limited
    Inventors: Chandra S. Bontu, Shavantha Kularatna, Shamim A. Rahman, Yonghai Gu, Peter Barany
  • Publication number: 20020142771
    Abstract: Apparatus, and an associated method, for a mobile communication system in which handovers of communications are effectuated between access points of the communication system as a mobile node travels there through. A manner is provided by which to perform handover evaluation functions more efficiently by performing at least some of the handover evaluations at the access point to which a mobile node is attached. And, a manner is provided by which to provide care-of-addresses formed of temporary identifiers to temporarily identify a mobile node to permit the routing of packet data thereto during a communication session.
    Type: Application
    Filed: March 30, 2001
    Publication date: October 3, 2002
    Inventors: Yousuf Saifullah, Basavaraj Patil, Shavantha Kularatna, Rene Purnadi, Stefano Faccin
  • Patent number: 6445745
    Abstract: A method for phase encoding DPSK and N-PSK which maintains phase continuity and which does not require any reference symbols when using N-PSK. A sequence of known DPSK phases are encoded with respect to an initial phase. The N-PSK phases are then all offset by this same initial phase. The known DPSK phases can be used at a receiver to determine a sum consisting of the initial phase and any further phase shift introduced by the channel, and this sum is used to decode the unknown N-PSK phases. The method is more generally applicable to any case where a switch between a phase encoding method which requires an absolute phase reference and a phase encoding method which does not have an absolute phase reference is to be implemented on a single carrier or channel.
    Type: Grant
    Filed: May 6, 1999
    Date of Patent: September 3, 2002
    Assignee: Nortel Networks Limited
    Inventors: Chandra S. Bontu, Yonghai Gu, Shavantha Kularatna, Peter Barany
  • Patent number: 6418137
    Abstract: A base station produces a power control bit dependent on SNR (signal-to-noise ratio) determined for each time slot of a signal received from a remote station of a cellular communications system. If the SNR exceeds an upper threshold by an upper threshold margin, the power control bit is a binary 0 and the upper threshold margin is increased; if the SNR is below a lower threshold by a lower threshold margin, the power control bit is a binary 1 and the lower threshold margin is increased; and otherwise the power control bit alternates its binary value for successive time slots and setting the threshold margins are reset. In the remote station, the power control bits are accumulated by a bidirectional counter and the transmitted signal power is only changed up or down in response to the count exceeding a respective threshold.
    Type: Grant
    Filed: December 14, 1998
    Date of Patent: July 9, 2002
    Assignee: Nortel Networks Limited
    Inventors: Chandra Sekhar Bontu, Shavantha Kularatna, N. Gamini Senarath, Karl D. Mann, Peter Anthony Barany
  • Publication number: 20010033563
    Abstract: The method and system provides a data packet encapsulated with protocol data according to an embodiment of the invention. A data packet for communication may be associated with a TLLI and a NSAPI identifying a communications path between a BSS and a SGSN. The method and system provides a BVC associated with the BSS and the SGSN and a NSE that provides communication service to the BVC over NS-VC. The BVC, NSE and NS-VC may be associated with the TLLI and NSAPI. The encapsulated protocol data comprises UDP and IP. UDP provides UDP ports associated with NS-VC. The UDP ports identified as data designated as either real time or non-real time services. IP provides an IP address identifying the NSE providing service to the BVC. The data packet encapsulated with UDP and IP provides for more efficient, flexible and reliable communications between a BSS and a SGSN.
    Type: Application
    Filed: February 16, 2001
    Publication date: October 25, 2001
    Inventors: Tuomas Niemela, Shkumbin Hamiti, Risto Mononen, Shavantha Kularatna