OVERHEAD REDUCTION AND RELIABILITY ENHANCEMENTS FOR DL CONTROL SIGNALING
Methods, user equipment (UE), and base stations for downlink control information (DCI) formats reception or transmission are provided. A method of operating a UE to transmit a physical uplink shared channel (PUSCH) includes receiving a configuration for a number of bits for a field that indicates a parameter in a first downlink control information (DCI) format; and receiving a physical downlink control channel (PDCCH) that provides either the first DCI format scheduling the PUSCH or a second DCI format scheduling the PUSCH. The second DCI format includes a field with a predetermined number of bits that indicates the parameter. A minimum number of bits for the field in the first DCI format is smaller than the predetermined number of bits for the field in the second DCI format. The method also includes transmitting the PUSCH.
1 . A method for a user equipment (UE) to transmit a physical uplink shared channel (PUSCH), the method comprising:
receiving a configuration for a number of bits for a field that indicates a parameter in a first downlink control information (DCI) format; and
receiving a physical downlink control channel (PDCCH) that provides either the first DCI format scheduling the PUSCH or a second DCI format scheduling the PUSCH, the second DCI format including a field with a predetermined number of bits that indicates the parameter, wherein a minimum number of bits for the field in the first DCI format is smaller than the predetermined number of bits for the field in the second DCI format; and
transmitting the PUSCH.
2 . The method of claim 1 , wherein receiving the PDCCH further comprises:
receiving the PDCCH in a user equipment search space (USS) when the PDCCH provides the first DCI format; or
receiving the PDCCH in a common search space (CSS) when the PDCCH provides the second DCI format.
3 . The method of claim 1 , further comprising receiving a configuration for a number of resource blocks (RBs) in a resource block group (RBG), wherein:
the first DCI format includes a frequency domain resource allocation (FDRA) field,
the second DCI format includes the FDRA field,
a value of the FDRA field indicates a number of RBGs,
a number of bits of the FDRA field in the first DCI format is determined from a number of RBs in an active bandwidth part (BWP) and the number of RBs in the RBG, and
a number of bits of the FDRA field in the second DCI format is determined only from the number of RBs in the active BWP.
4 . The method of claim 1 , further comprising receiving a configuration for a number of bits of a hybrid automatic repeat request (HARQ) process number field in the first DCI format, wherein:
the second DCI format includes the HARQ process number field, and
the number of bits of the HARQ process number field in the first DCI format is smaller than a number of bits of the HARQ process number field in the second DCI format.
5 . The method of claim 1 , further comprising receiving a configuration indicating an absence of a redundancy version (RV) field in the first DCI format,
wherein the RV field is present in the second DCI format.
6 . The method of claim 1 , further comprising:
receiving a configuration for a number of bits for a modulation and coding scheme (MCS) field in the first DCI format; and
receiving a configuration for a mapping of MCS field values to MCS values.
7 . The method of claim 1 , further comprising transmitting information that indicates a capability for scheduling with a subset of DCI formats, from a predetermined set of DCI formats, that includes the first DCI format and the second DCI format.
8 . A user equipment (UE) comprising:
a receiver configured to:
receive a configuration for a number of bits for a field that indicates a parameter in a first downlink control information (DCI) format; and
receive a physical downlink control channel (PDCCH) that provides either the first DCI format scheduling a physical uplink shared channel (PUSCH) or a second DCI format scheduling the PUSCH, the second DCI format including a field with a predetermined number of bits that indicates the parameter, wherein a minimum number of bits for the field in the first DCI format is smaller than the predetermined number of bits for the field in the second DCI format; and
a transmitter configured to transmit the PUSCH.
9 . The UE of claim 8 , wherein the receiver is further configured to:
receive the PDCCH in a user equipment search space (USS) when the PDCCH provides the first DCI format; or
receive the PDCCH in a common search space (CSS) when the PDCCH provides the second DCI format.
10 . The UE of claim 9 , wherein the receiver is further configured to receive a configuration for a number of resource blocks (RBs) in a resource block group (RBG), wherein:
the first DCI format includes a frequency domain resource allocation (FDRA) field,
the second DCI format includes the FDRA field,
a value of the FDRA field indicates a number of RBGs,
a number of bits of the FDRA field in the first DCI format is determined from a number of RBs in an active bandwidth part (BWP) and the number of RBs in the RBG, and
a number of bits of the FDRA field in the second DCI format is determined only from the number of RBs in the active BWP.
11 . The UE of claim 8 , wherein:
the receiver is further configured to receive a configuration for a number of bits of a hybrid automatic repeat request (HARQ) process number field in the first DCI format, and
the second DCI format includes the HARQ process number field, and
the number of bits of the HARQ process number field in the first DCI format is smaller than a number of bits of the HARQ process number field in the second DCI format.
12 . The UE of claim 8 , wherein:
the receiver is further configured to receive a configuration indicating an absence of a redundancy version (RV) field in the first DCI format, and
the RV field is present in the second DCI format.
13 . The UE of claim 8 , wherein the receiver is further configured to:
receive a configuration for a number of bits for a modulation and coding scheme (MCS) field in the first DCI format; and
receive a configuration for a mapping of MCS field values to MCS values.
14 . The UE of claim 8 , wherein the transmitter is further configured to transmit information that indicates a capability for scheduling with a subset of DCI formats, from a predetermined set of DCI formats, that includes the first DCI format and the second DCI format.
15 . A base station comprising:
a transmitter configured to:
transmit a configuration for a number of bits for a field that indicates a parameter in a first downlink control information (DCI) format; and
transmit a physical downlink control channel (PDCCH) that provides either the first DCI format scheduling a physical uplink shared channel (PUSCH) or a second DCI format scheduling the PUSCH, the second DCI format including a field with a predetermined number of bits that indicates the parameter, wherein a minimum number of bits for the field in the first DCI format is smaller than the predetermined number of bits for the field in the second DCI format; and
a receiver configured to receive the PUSCH.
16 . The base station of claim 15 , wherein the transmitter is further configured to:
transmit the PDCCH in a user equipment search space (USS) when the PDCCH provides the first DCI format; or
transmit the PDCCH in a common search space (CSS) when the PDCCH provides the second DCI format.
17 . The base station of claim 15 , wherein the transmitter is further configured to transmit a configuration for a number of resource blocks (RBs) in a resource block group (RBG), wherein:
the first DCI format includes a frequency domain resource allocation (FDRA) field,
the second DCI format includes the FDRA field,
a value of the FDRA field indicates a number of RBGs,
a number of bits of the FDRA field in the first DCI format is determined from a number of RBs in an active bandwidth part (BWP) and the number of RBs in the RBG, and
a number of bits of the FDRA field in the second DCI format is determined only from the number of RBs in the active BWP.
18 . The base station of claim 15 , wherein:
the transmitter is further configured to transmit a configuration indicating an absence of a redundancy version (RV) field in the first DCI format, and
the RV field is present in the second DCI format.
19 . The base station of claim 15 , wherein the transmitter is further configured to:
transmit a configuration for a number of bits for a modulation and coding scheme (MCS) field in the first DCI format; and
transmit a configuration for a mapping of MCS field values to MCS values.
20 . The base station of claim 15 , wherein the receiver is further configured to receive information that indicates a capability for scheduling with a subset of DCI formats, from a predetermined set of DCI formats, that includes the first DCI format and the second DCI format.