Transmission diversity and multiplexing for harq-ack signals in communication systems

Abstract

A method and apparatus are described for a User Equipment (UE) to transmit in a control channel ACKnowledgement signals associated with a Hybrid Automatic Repeat reQuest process (HARQ-ACK signals) in response to receiving Transport Blocks (TBs) transmitted from a base station. The UE conveys the HARQ-ACK information by selecting one resource from multiple resources in the control channel and by selecting a constellation point of the modulation scheme for the HARQ-ACK signal. Transmission diversity is supported using different control channel resources that are already available to the UE without configuring additional resources. Design principles are described to optimally map the HARQ-ACK information to control channel resources and modulation constellation points for a Time Division Duplex (TDD) system and for a Frequency Division Duplex (FDD) system.

What is claimed is: 
     
         1 . A method for transmitting a hybrid automatic repeat request-acknowledgement (HARQ-ACK) signal in a communication system, the method comprising:
 receiving at least one transport block on a physical downlink shared channel (PDSCH) indicated by a physical downlink control channel (PDCCH) on a cell;   and   transmitting at least one HARQ-ACK signal for the at least one transport block on a first and second physical uplink control channel (PUCCH) resource,   wherein the PDCCH comprises at least one control channel element (CCE), and   wherein the first PUCCH resource is identified based on a first CCE used for transmission of the PDCCH, and for a transmission mode that supports up to two transport blocks, and the second PUCCH resource is identified based on the first CCE+1.   
     
     
         2 . The method of  claim 1 , further comprising:
 receiving at least one transport block on a PDSCH indicated by a PDCCH on another cell.   
     
     
         3 . The method of  claim 1 , wherein the cell is a first cell. 
     
     
         4 . The method of  claim 2 , further comprising:
 identifying a third PUCCH resource and a fourth PUCCH resource for the another cell.   
     
     
         5 . The method of  claim 1 , wherein a HARQ-ACK state for the at least one HARQ-ACK signal for the at least one transport block is mapped to one of the first and second PUCCH resource. 
     
     
         6 . A method for receiving a hybrid automatic repeat request-acknowledgement (HARQ-ACK) signal in a communication system, the method comprising:
 transmitting at least one transport block on a physical downlink shared channel (PDSCH) indicated by a physical downlink control channel (PDCCH) on a cell; and   receiving at least one HARQ-ACK signal for the at least one transport block on a first and second physical uplink control channel (PUCCH) resource,   wherein the PDCCH comprises at least one control channel element (CCE), and   wherein the first PUCCH resource is identified based on a first CCE used for transmission of the PDCCH, and for a transmission mode that supports up to two transport blocks, and the second PUCCH resource is identified based on the first CCE+1.   
     
     
         7 . The method of  claim 6 , further comprising:
 transmitting at least one transport block on a PDSCH indicated by a PDCCH in another cell.   
     
     
         8 . The method of  claim 6 , wherein the cell is a first cell. 
     
     
         9 . The method of  claim 6 , wherein a HARQ-ACK state for the at least one HARQ-ACK signal for the at least one transport block is mapped to one of the first and second PUCCH resources. 
     
     
         10 . An apparatus for transmitting a hybrid automatic repeat request-acknowledgement (HARQ-ACK) signal in a communication system, the apparatus comprising:
 a receiver configured to receive at least one transport block on a physical downlink shared channel (PDSCH) indicated by a physical downlink control channel (PDCCH) on a cell; and   a transmitter configured to transmit at least one HARQ-ACK signal for the at least one transport block on a first and second physical uplink control channel (PUCCH) resource,   wherein the PDCCH comprises at least one Control Channel Element (CCE), and   wherein the first PUCCH resource is identified based on a first CCE used for transmission of the PDCCH, and for a transmission mode that supports up to two transport blocks, and the second PUCCH resource is identified based on the first CCE+1.   
     
     
         11 . The apparatus of  claim 10 , wherein the receiver receives at least one transport block on a PDSCH indicated by a PDCCH in another cell. 
     
     
         12 . The apparatus of  claim 10 , wherein the cell a first cell. 
     
     
         13 . The apparatus of  claim 11 , further comprising:
 a processor configured to identify a third PUCCH resource and a fourth PUCCH resource for the another cell.   
     
     
         14 . The apparatus of  claim 10 , wherein a HARQ-ACK state for the at least one HARQ- ACK signal for the at least one transport block is mapped to one of the first and second PUCCH resources. 
     
     
         15 . An apparatus for receiving a hybrid automatic repeat request-acknowledgement (HARQ-ACK) signal in a communication system, the apparatus comprising:
 a transmitter configured to transmit at least one transport block on a physical downlink shared channel (PDSCH) indicated by a physical downlink control channel (PDCCH) on a cell; and   a receiver configured to receive at least one HARQ-ACK signal for the at least one transport block on a first and second physical uplink control channel (PUCCH) resource,   wherein the PDCCH comprises at least one control channel element (CCE), and   wherein the first PUCCH resource is identified based on a first CCE used for transmission of the PDCCH, and for a transmission mode that supports up to two transport blocks, and the second PUCCH resource is identified based on the first CCE+1.   
     
     
         16 . The apparatus of  claim 15 , wherein the transmitter transmits at least one transport block on a PDSCH indicated by a PDCCH in another cell. 
     
     
         17 . The apparatus of  claim 15 , wherein the cell is a first cell. 
     
     
         18 . The apparatus of  claim 15 , wherein a HARQ-ACK state for the at least one HARQ-ACK signal for the at least one transport block is mapped to one of the first and second PUCCH resources.