Method and apparatus for DCI size for multi-cell scheduling
Downlink control information (DCI) size determination for multi-cell scheduling. A method includes receiving first information for a set of cells, identifying first combinations of cells from the set of cells, and determining a first maximum size among first sizes of a first DCI format. The first DCI format schedules physical downlink shared channel (PDSCH) receptions on a first combination of cells from the first combinations of cells, and the first sizes correspond to the first combinations of cells. The method further includes receiving the first DCI format based on the first maximum size.
1 . A method comprising:
receiving first information for a set of cells;
identifying first combinations of cells and second combinations of cells from the set of cells;
determining a first maximum size among first sizes of a first downlink control information (DCI) format, wherein:
the first DCI format schedules physical downlink shared channel (PDSCH) receptions on a first combination of cells from the first combinations of cells, and
the first sizes correspond to the first combinations of cells;
determining a second maximum size among second sizes of a second DCI format, wherein:
the second DCI format schedules physical uplink shared channel (PUSCH) transmissions on a second combination of cells from the second combinations of cells, and
the second sizes correspond to the second combinations of cells;
determining:
a third size for a third DCI format for scheduling a PDSCH reception on a reference cell from the set of cells, and
a fourth size for a fourth DCI format for scheduling a PUSCH transmission on the reference cell;
determining a number of sizes among the first maximum size, the second maximum size, the third size, and the fourth size exceeds a predetermined number of sizes for the reference cell;
determining a first number of padding bits that is equal to a difference between the fourth size and the third size;
receiving the first DCI format based on the first maximum size and the second DCI format based on the second maximum size, and
receiving the third DCI format including the first number of padding bits when the third size is smaller than the fourth size.
2 . The method of claim 1 , further comprising receiving the fourth DCI format including the first number of padding bits when the fourth size is smaller than the third size.
3 . The method of claim 1 , further comprising:
determining:
a number of sizes among the first maximum size, the second maximum size, and a larger of the third size and the fourth size exceeds the predetermined number of sizes for the reference cell,
a second number of padding bits that is equal to a difference between the second maximum size and the first maximum size,
the first maximum size by adding the second number of padding bits to the first maximum size when the first maximum size is smaller than the second maximum size, and
the second maximum size by adding the second number of padding bits to the second maximum size when the second maximum size is smaller than the first maximum size.
4 . The method of claim 1 , further comprising:
determining a second number of padding bits for the first DCI format, wherein:
the first DCI format has a first size,
the first size is smaller than the first maximum size, and
the second number of padding bits is equal to a difference between the first maximum size and the first size.
5 . The method of claim 1 , further comprising:
receiving second information for a field of the first DCI format, wherein the field provides a value that is common for all cells in the first combination of cells; and
determining:
a maximum bit-width of M bits among bit-widths for the field corresponding to all cells in the set of cells,
a bit-width of N bits for the field corresponding to a first cell from the first combination of cells, wherein N≤M, and
a number N of least significant bits (LSBs) of the value for the first cell, wherein a PDSCH reception, from the PDSCH receptions, on the first cell is based on the number N of LSBs of the value.
6 . The method of claim 1 , wherein:
a frequency domain resource allocation (FDRA) field in the first DCI format includes values for all cells in the set of cells,
first values, from the values, of the FDRA field in the first DCI format are not reserved,
remaining values from the values for the FDRA field in the first DCI format are reserved, and
the first values have one-to-one association with the PDSCH receptions on the first combination of cells.
7 . The method of claim 1 , wherein:
a field in the first DCI format is predetermined or configured by higher layers to have separate values for different cells in the set of cells,
the set of cells include N cells,
the first combination of cells includes
N
cells
DL
cells from the set of cells, wherein
N
cells
DL
≤
N
,
and
the first DCI format includes only
N
cells
DL
values for the field, corresponding to the
N
cells
DL
cells.
8 . A user equipment (UE) comprising:
a transceiver configured to receive first information for a set of cells; and
a processor operably coupled to the transceiver, the processor configured to:
identify first combinations of cells and second combinations of cells from the set of cells;
determine a first maximum size among first sizes of a first downlink control information (DCI) format, wherein:
the first DCI format schedules physical downlink shared channel (PDSCH) receptions on a first combination of cells from the first combinations of cells, and
the first sizes correspond to the first combinations of cells,
determine a second maximum size among second sizes of a second DCI format, wherein:
the second DCI format schedules physical uplink shared channel (PUSCH) transmissions on a second combination of cells from the second combinations of cells, and
the second sizes correspond to the second combinations of cells;
determine:
a third size for a third DCI format for scheduling a PDSCH reception on a reference cell from the set of cells, and
a fourth size for a fourth DCI format for scheduling a PUSCH transmission on the reference cell;
determine a number of sizes among the first maximum size, the second maximum size, the third size, and the fourth size exceeds a predetermined number of sizes for the reference cell;
determine a first number of padding bits that is equal to a difference between the fourth size and the third size,
wherein the transceiver is further configured to:
receive the first DCI format based on the first maximum size and the second DCI format based on the second maximum size, and
receive the third DCI format including the first number of padding bits when the third size is smaller than the fourth size.
9 . The UE of claim 8 , wherein the transceiver is further configured to receive the fourth DCI format including the first number of padding bits when the fourth size is smaller than the third size.
10 . The UE of claim 8 , wherein the processor is further configured to determine:
a number of sizes among the first maximum size, the second maximum size, and a larger of the third size and the fourth size exceeds the predetermined number of sizes for the reference cell,
a second number of padding bits that is equal to a difference between the second maximum size and the first maximum size,
the first maximum size by adding the second number of padding bits to the first maximum size when the first maximum size is smaller than the second maximum size, and
the second maximum size by adding the second number of padding bits to the second maximum size when the second maximum size is smaller than the first maximum size.
11 . The UE of claim 8 , wherein:
the processor is further configured to determine a second number of padding bits for the first DCI format,
the first DCI format has a first size,
the first size is smaller than the first maximum size, and
the second number of padding bits is equal to a difference between the first maximum size and the first size.
12 . The UE of claim 8 , wherein:
the transceiver is further configured to receive second information for a field of the first DCI format,
the field provides a value that is common for all cells in the first combination of cells,
the processor is further configured to determine:
a maximum bit-width of M bits among bit-widths for the field corresponding to all cells in the set of cells,
a bit-width of N bits for the field corresponding to a first cell from the first combination of cells, wherein N≤M, and
a number N of least significant bits (LSBs) of the value for the first cell, and
a PDSCH reception, from the PDSCH receptions, on the first cell is based on the number N of LSBs of the value.
13 . The UE of claim 8 , wherein:
a frequency domain resource allocation (FDRA) field in the first DCI format includes values for all cells in the set of cells,
first values, from the values, of the FDRA field in the first DCI format are valid,
remaining values from the values for the FDRA field in the first DCI format are invalid, and
the first values have one-to-one association with the PDSCH receptions on the first combination of cells.
14 . The UE of claim 8 , wherein:
a field in the first DCI format is predetermined or configured by higher layers to have separate values for different cells in the set of cells,
the set of cells include N cells,
the first combination of cells includes
N
cells
DL
cells from the set of cells, wherein
N
cells
DL
≤
N
,
and
the first DCI format includes only
N
cells
DL
values for the field, corresponding to the
N
cells
DL
cells.
15 . A base station comprising:
a transceiver configured to transmit first information for a set of cells; and
a processor operably coupled to the transceiver, the processor configured to:
identify first combinations of cells and second combinations of cells from the set of cells;
determine a first maximum size among first sizes of a first downlink control information (DCI) format, wherein:
the first DCI format schedules physical downlink shared channel (PDSCH) transmissions on a first combination of cells from the first combinations of cells, and
the first sizes correspond to the first combinations of cells;
determine a second maximum size among second sizes of a second DCI format, wherein:
the second DCI format schedules physical uplink shared channel (PUSCH) transmissions on a second combination of cells from the second combinations of cells, and
the second sizes correspond to the second combinations of cells;
determine:
a third size for a third DCI format for scheduling a PDSCH reception on a reference cell from the set of cells, and
a fourth size for a fourth DCI format for scheduling a PUSCH transmission on the reference cell;
determine a number of sizes among the first maximum size, the second maximum size, the third size, and the fourth size exceeds a predetermined number of sizes for the reference cell;
determine a first number of padding bits that is equal to a difference between the fourth size and the third size,
wherein the transceiver is further configured to:
transmit the first DCI format based on the first maximum size and the second DCI format based on the second maximum size, and
transmit the third DCI format including the first number of padding bits when the third size is smaller than the fourth size.
16 . The base station of claim 15 , wherein the transceiver is further configured to transmit the fourth DCI format by including the first number of padding bits when the fourth size is smaller than the third size.
17 . The base station of claim 15 , wherein the processor is further configured to determine:
a number of sizes among the first maximum size, the second maximum size, and a larger of third size and the fourth size exceeds the predetermined number of sizes for the reference cell,
a second number of padding bits that is equal to a difference between the second maximum size and the first maximum size,
the first maximum size by adding the second number of padding bits to the first maximum size when the first maximum size is smaller than the second maximum size, and
the second maximum size by adding the second number of padding bits to the second maximum size when the second maximum size is smaller than the first maximum size.
18 . The base station of claim 15 , wherein:
the processor is further configured to determine a second number of padding bits for the first DCI format,
the first DCI format has a first size,
the first size is smaller than the first maximum size, and
the second number of padding bits is equal to a difference between the first maximum size and the first size.
19 . The base station of claim 15 , wherein:
the transceiver is further configured to transmit second information for a field of the first DCI format,
the field provides a value that is common for all cells in the first combination of cells,
the processor is further configured to determine:
a maximum bit-width of M bits among bit-widths for the field corresponding to all cells in the set of cells,
a bit-width of N bits for the field corresponding to a first cell from the first combination of cells, wherein N≤M, and
a number N of least significant bits (LSBs) of the value for the first cell, and
a PDSCH transmission, from the PDSCH transmissions, on the first cell is based on the number N of LSBs of the value.
20 . The base station of claim 15 , wherein:
a field in the first DCI format is predetermined or configured by higher layers to have separate values for different cells in the set of cells,
the set of cells include N cells,
the first combination of cells includes
N
cells
DL
cells from the set of cells, wherein
N
cells
DL
≤
N
,
and
the first DCI format includes only
N
cells
DL
values ror ie nieia, corresponding to the
N
cells
DL
cells.