Compact dci for urllc

Abstract

Certain aspects of the present disclosure provide techniques for compact downlink control information (DCI) signaling design for ultra-reliable low-latency communications (URLLC). A method for wireless communications performed by a base station (BS) is provided. The method generally includes generating DCI, the DCI scheduling at least one transmission, according to a first DCI format. The first DCI format is compressed relative to a second DCI format and includes a carrier indicator field (CIF) and/or a rate-matching indicator field. The BS transmits the DCI to a user equipment (UE). The UE communicates with the BS based on the received DCI.

What is claimed is: 
     
         1 . A method for wireless communications by a user equipment (UE), comprising:
 receiving downlink control information (DCI) from a base station (BS), the DCI scheduling at least one transmission and having a first DCI format that is compressed relative to a second DCI format, wherein the first DCI format includes at least one of: a carrier indicator field (CIF) or a rate-matching indicator field; and   communicating with the BS based on the received DCI.   
     
     
         2 . The method of  claim 1 , wherein the DCI schedules an ultra-reliable low-latency communications (URLLC) transmission. 
     
     
         3 . The method of  claim 1 , wherein the second DCI format comprises a DCI format for enhanced mobile broadband (eMBB) communications. 
     
     
         4 . The method of  claim 1 , wherein one or more fields of the first DCI format uses fewer bits than one or more fields of the second DCI format. 
     
     
         5 . The method of  claim 1 , wherein the CIF comprises an indication of an index of a component carrier (CC) on which the at least one transmission is scheduled. 
     
     
         6 . The method of  claim 1 , wherein the CIF consists of 1 or 2 bits. 
     
     
         7 . The method of  claim 1 , further comprising receiving radio resource control (RRC) signaling from the BS configuring the UE with a first CIF table for the first DCI format and a second CIF table for the second DCI format, different from the first CIF table. 
     
     
         8 . The method of  claim 1 , wherein the DCI comprises an uplink DCI or a downlink DCI. 
     
     
         9 . The method of  claim 1 , further comprising transmitting in a cell on a physical uplink shared channel (PUSCH) with repetitions only within the cell when the CIF is not included in the DCI. 
     
     
         10 . The method of  claim 9 , further comprising transmitting the PUSCH with repetitions in different cells when the CIF is included in the DCI. 
     
     
         11 . The method of  claim 1 , wherein the DCI includes multiple CIFs, each CIF indicating a different cell for a repetition of the scheduled transmission. 
     
     
         12 . The method of  claim 1 , wherein:
 the DCI is received in a physical downlink control channel (PDCCH);   the at least one scheduled transmission comprises a physical downlink shared channel (PDSCH) transmission;   the rate-matching indicator field comprises an indication of whether the scheduled PDSCH was rate-matched around the PDCCH; and   performing de-rate-matching for the PDSCH based on the indication.   
     
     
         13 . The method of  claim 12 , wherein the rate-matching indicator field further comprises an indication of how the rate-matching was performed. 
     
     
         14 . The method of  claim 12 , wherein different rate-matching patterns are indicated or configured for different PDSCH repetitions. 
     
     
         15 . The method of  claim 14 , further comprising receiving radio resource control (RRC) signaling configuring the UE for the different rate-matching for the PDSCH repetitions, wherein the de-rate-matching is performed further based on the RRC configuration. 
     
     
         16 . The method of  claim 14 , wherein the UE is configured for different repetition-specific interpretations of the rate-matching indicator field. 
     
     
         17 . The method of  claim 12 , further comprising receiving radio resource control (RRC) signaling configuring a first rate-matching table for PDSCH without repetition and a second rate-matching table, different than the first rate-matching table, for PDSCH with repetitions. 
     
     
         18 . An apparatus for wireless communications, comprising:
 means for receiving downlink control information (DCI), from a base station (BS), the DCI scheduling at least one transmission and having a first DCI format that is compressed relative to a second DCI format, wherein the first DCI format includes at least one of: a carrier indicator field (CIF) or a rate-matching indicator field; and   means for communicating with the BS based on the received DCI.   
     
     
         19 . The apparatus of  claim 18 , wherein the DCI schedules an ultra-reliable low-latency communications (URLLC) transmission. 
     
     
         20 . The apparatus of  claim 18 , wherein one or more fields of the first DCI format uses fewer bits than one or more fields of the second DCI format. 
     
     
         21 . The apparatus of  claim 18 , wherein the CIF consists of 1 or 2 bits. 
     
     
         22 . The apparatus of  claim 18 , further comprising means for receiving radio resource control (RRC) signaling from the BS configuring the apparatus with a first CIF table for the first DCI format and a second CIF table for the second DCI format, different from the first CIF table. 
     
     
         23 . The apparatus of  claim 18 , further comprising means for transmitting in a cell on a physical uplink shared channel (PUSCH) with repetitions only within the cell when the CIF is not included in the DCI. 
     
     
         24 . The apparatus of  claim 23 , further comprising means for transmitting the PUSCH with repetitions in different cells when the CIF is included in the DCI. 
     
     
         25 . The apparatus of  claim 18 , wherein the DCI includes multiple CIFs, each CIF indicating a different cell for a repetition of the scheduled transmission. 
     
     
         26 . The apparatus of  claim 18 , further comprising means for receiving radio resource control (RRC) signaling configuring the apparatus for different rate-matching for physical downlink shared channel (PDSCH) repetitions, wherein the de-rate-matching is performed further based on the RRC configuration. 
     
     
         27 . The apparatus of  claim 18 , wherein the apparatus is configured for different repetition-specific interpretations of the rate-matching indicator field. 
     
     
         28 . The apparatus of  claim 18 , further comprising means for receiving radio resource control (RRC) signaling configuring a first rate-matching table for a physical downlink shared channel (PDSCH) without repetition and a second rate-matching table, different than the first rate-matching table, for PDSCH with repetitions. 
     
     
         29 . An apparatus for wireless communications, comprising:
 at least one processor coupled with a memory and configured to:
 receive downlink control information (DCI), from a base station (BS), the DCI scheduling at least one transmission and having a first DCI format that is compressed relative to a second DCI format, wherein the first DCI format includes at least one of: a carrier indicator field (CIF) or a rate-matching indicator field; and 
 communicate with the BS based on the received DCI. 
   
     
     
         30 . A computer readable medium having computer executable code stored thereon for wireless communications, comprising:
 code for receiving downlink control information (DCI), from a base station (BS), the DCI scheduling at least one transmission and having a first DCI format that is compressed relative to a second DCI format, wherein the first DCI format includes at least one of: a carrier indicator field (CIF) or a rate-matching indicator field; and   code for communicating with the BS based on the received DCI.