Facilitating uplink synchronization in TD-SCDMA multi-carrier systems
AssigneeQUALCOMM Incorporated
InventorsTom Chin, Guangming Shi, Kuo-Chun Lee
Life of this patent
Estimating the term…
Abstract
Uplink synchronization processes in multi-carrier time division-synchronous code division multiple access (TD-SCDMA) systems include determining uplink transmission timing for a first carrier frequency and performing uplink synchronization on the other carrier frequencies based on the transmission timing of the first carrier frequency. The transmission timing may be adjusted based on a timing offset that is measured between the received downlink pilot signals of the various carrier frequencies. User equipment may perform uplink synchronization individually with each of the carriers serviced by a particular Node B after receiving synchronization information regarding those carrier frequencies.
Claims24
A method for uplink synchronization in a multi-carrier time division-synchronous code division multiple access (TD-SCDMA) system, said method comprising:
- performing uplink synchronization for a first frequency in said multi-carrier TD-SCDMA system to determine a first timing advance for said first frequency;
- receiving, at a first time, a first downlink transmission on said first frequency in said multi-carrier TD-SCDMA system;
- receiving, at a second time, a second downlink transmission on at least one secondary frequency in said multi-carrier TD-SCDMA system, in which said second time is different from said first time;
- measuring a timing offset as a difference between said first time and said second time;
- scheduling uplink transmissions on said first frequency at a third time based on the first timing advance;
- and
- scheduling uplink transmissions on said at least one secondary frequency at a fourth time that is offset from the third time by the timing offset.
A user equipment configured to perform uplink synchronization in a multi-carrier time division-synchronous code division multiple access (TD-SCDMA) system, said user equipment comprising:
- means for performing uplink synchronization for a first frequency in said multi-carrier TD-SCDMA system to determine a first timing advance for said first frequency;
- means for receiving, at a first time, a first downlink transmission on said first frequency in said multi-carrier TD-SCDMA system;
- means for receiving, at a second time, a second downlink transmission on at least one secondary frequency in said multi-carrier TD-SCDMA system, in which said second time is different from said first time;
- means for measuring a timing offset as a difference between said first time and said second time;
- means for scheduling uplink transmissions on said first frequency at a third time based on the first timing advance;
- and
- means for scheduling uplink transmissions on said at least one secondary frequency at a fourth time that is offset from the third time by the timing offset.
A computer program product having a non-transitory computer readable medium with program code stored thereon, said program code comprising:
- program code to perform uplink synchronization for a first frequency in said multi-carrier TD-SCDMA system to determine a first timing advance for said first frequency;
- program code to receive, at a first time, a first downlink transmission on said first frequency in said multi-carrier TD-SCDMA system;
- program code to receive, at a second time, a second downlink transmission on at least one secondary frequency in said multi-carrier TD-SCDMA system, in which said second time is different from said first time;
- program code to measure a timing offset as a difference between said first time and said second time;
- program code to schedule uplink transmissions on said first frequency at a third time based on the first timing advance;
- and
- program code to schedule uplink transmissions on said at least one secondary frequency at a fourth time that is offset from the third time by the timing offset.
A user equipment configured for wireless communication in a multi-carrier time division-synchronous code division multiple access (TD-SCDMA) system, said user equipment comprising:
- at least one processor;
- and
- a memory coupled to the at least one processor, wherein the at least one processor is configured:
- to perform uplink synchronization for a first frequency in said multi-carrier TD-SCDMA system to determine a first timing advance for said first frequency;
- to receive, at a first time, a first downlink transmission on said first frequency in said multi-carrier TD-SCDMA system;
- to receive, at a second time, a second downlink transmission on at least one secondary frequency in said multi-carrier TD-SCDMA system, in which said second time is different from said first time;
- to measure a timing offset as a difference between said first time and said second time;
- to schedule uplink transmissions on said first frequency at a third time based on the first timing advance;
- and
- to schedule uplink transmissions on said at least one secondary frequency at a fourth time that is offset from the third time by the timing offset.
A method for uplink synchronization in a multi-carrier time division-synchronous code division multiple access (TD-SCDMA) system, said method comprising:
- transmitting synchronization information to a target cell for each frequency of a plurality of carrier frequencies serviced by said target cell;
- receiving a fast physical access channel (FPACH) acknowledgement signal (ACK) associated with said each frequency;
- obtaining individual transmission timing values from said received FPACH ACK for said each frequency;
- and
- performing uplink synchronization individually on said each frequency of said plurality of carrier frequencies assigned by said target cell.
A user equipment for uplink synchronization in a multi-carrier time division-synchronous code division multiple access (TD-SCDMA) system, said user equipment comprising:
- means for transmitting synchronization information to a target cell for each frequency of a plurality of carrier frequencies serviced by said target cell;
- means for receiving a fast physical access channel (FPACH) acknowledgement signal (ACK) associated with said each frequency;
- means for obtaining individual transmission timing values from said received FPACH ACK for said each frequency;
- and
- means for performing uplink synchronization individually on said each frequency of said plurality of carrier frequencies assigned by said target cell.
A computer program product having a non-transitory computer readable medium with program code stored thereon, said program code comprising:
- program code to transmit synchronization information to a target cell for each frequency of a plurality of carrier frequencies serviced by said target cell;
- program code to receive a fast physical access channel (FPACH) acknowledgement signal (ACK) associated with said each frequency;
- program code to obtain individual transmission timing values from said received FPACH ACK for said each frequency;
- and
- program code to perform uplink synchronization individually on said each frequency of said plurality of carrier frequencies assigned by said target cell.
A user equipment configured for wireless communication in a multi-carrier time division-synchronous code division multiple access (TD-SCDMA) system, said user equipment comprising:
- at least one processor;
- and
- a memory coupled to the at least one processor, wherein the at least one processor is configured:
- to transmit synchronization information to a target cell for each frequency of a plurality of carrier frequencies serviced by said target cell;
- to receive a fast physical access channel (FPACH) acknowledgement signal (ACK) associated with said each frequency;
- to obtain individual transmission timing values from said received FPACH ACK for said each frequency;
- and
- to perform uplink synchronization individually on said each frequency of said plurality of carrier frequencies assigned by said target cell.
Dependencies are inferred from the claim text.