Harq design for high performance wireless backhaul

Abstract

A method of operating a wireless communication system is disclosed. The method includes receiving respective downlink transmissions at N second transceivers from a first transceiver, where N is a positive integer greater than 1. The reception acknowledgment signals by the N second transceivers are combined into a single reception acknowledgment signal and transmitted to the first transceiver.

What is claimed is: 
     
         1 . A method of operating a wireless communication system, comprising:
 receiving N downlink transmissions at a second transceiver from a first transceiver, where N is a positive integer greater than 1;   combining reception acknowledgment signals for the respective N downlink transmissions into a single reception acknowledgment signal; and   transmitting the single reception acknowledgment signal to the first transceiver, wherein N is independently configured by the first transceiver for the second transceiver.   
     
     
         2 . The method of  claim 1 , wherein first transceiver is a hub unit (HU) of a wireless backhaul system, and wherein the second transceiver is a remote unit (RU) of the wireless backhaul system. 
     
     
         3 . The method of  claim 1 , wherein N is configured in response to a channel quality between the first transceiver and a respective one of the second transceivers. 
     
     
         4 . The method of  claim 1 , wherein the downlink transmissions are received on a Physical Downlink Shared Channel (PDSCH), and wherein the single reception acknowledgment signal is transmitted on a Physical Uplink Control Channel (PUCCH). 
     
     
         5 . The method of  claim 1 , wherein the single reception acknowledgment signal is an acknowledgment (ACK) when all N downlink transmissions are correctly received at the second transceiver, and wherein the single reception acknowledgment signal is a negative acknowledgment (NACK) when at least one of the N downlink transmissions is incorrectly received at the second transceiver. 
     
     
         6 . The method of  claim 1 , comprising:
 receiving incorrectly a respective downlink transmission having a first allocation size at one of the second transceivers; and   receiving a retransmission of the incorrect downlink transmission having a second allocation size.   
     
     
         7 . The method of  claim 6 , comprising rate matching the retransmission to the second allocation size. 
     
     
         8 . The method of  claim 1 , wherein the downlink transmissions occur within a feedback window determined by a time division duplex (TDD) downlink/uplink frame configuration and uplink slot number of the TDD frame. 
     
     
         9 . The method of  claim 8 , wherein N is signaled to a second transceiver in a Physical Broadcast Channel (PBCH) within the feedback window. 
     
     
         10 . The method of  claim 8 , wherein the feedback window spans a plurality of time slots of a frame and a plurality of component carrier frequencies. 
     
     
         11 . The method of  claim 1 , wherein the N acknowledgment signals are combined in order of sequential time slots and component carrier frequencies. 
     
     
         12 . A method of operating a wireless communication system, comprising:
 receiving respective uplink transmissions at a first transceiver from M second transceivers, where M is a positive integer greater than 1;   combining reception acknowledgment signals for the respective M second transceivers into a single reception acknowledgment signal; and   transmitting the single reception acknowledgment signal to each of the M second transceivers.   
     
     
         13 . The method of  claim 12 , wherein first transceiver is a hub unit (HU) of a wireless backhaul system, and wherein the M second transceivers are remote units (RUs) of the wireless backhaul system. 
     
     
         14 . The method of  claim 12 , wherein the uplink transmissions are received on a Physical Downlink Shared Channel (PUSCH), and wherein the single reception acknowledgment signal is transmitted on a Physical HARQ Indicator Channel (PHICH). 
     
     
         15 . The method of  claim 12 , comprising receiving respective retransmitted uplink transmissions from the M second transceivers when at least one of the reception acknowledgment signals is negative (NACK). 
     
     
         16 . A method of operating a wireless communication system, comprising:
 transmitting downlink control information (DCI) from a first transceiver to a second transceiver indicating parameters for one of an uplink (UL) and downlink (DL) transmission; and   transmitting a preempt signal with the control information to indicate whether said transmission is preempted by one of an UL and DL retransmission.   
     
     
         17 . The method of  claim 16 , wherein the preempt bit has a first logic state for a retransmission of a previous transmission and the DCI indicates a format of the retransmission. 
     
     
         18 . The method of  claim 16 , wherein the preempt bit has a second logic state when no second transceiver served by the first transceiver is scheduled for said one of an UL and DL transmission. 
     
     
         19 . The method of  claim 16 , wherein the DCI from the first transceiver is all zero when no second transceiver served by the first transceiver is scheduled for said one of an UL and DL transmission. 
     
     
         20 . The method of  claim 16 , comprising:
 scheduling the second transceiver for said one of an UL and DL transmission in a dynamic allocation;   receiving a negative acknowledgment signal for the scheduling from the second transceiver;   setting the DCI from the first transceiver to all zero; and   setting the preempt bit to a first logic state.