Modified downlink control information to support low tier user equipment
Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive an indication of a modified physical downlink control channel (PDCCH) configuration for low tier UEs; receive downlink control information (DCI) configured according to the modified PDCCH configuration; and process the DCI according to the modified PDCCH configuration. Numerous other aspects are provided.
1. A method of wireless communication performed by a user equipment (UE), comprising:
receiving an indication of a modified physical downlink control channel (PDCCH) configuration for enhanced coverage;
receiving downlink control information (DCI) configured according to the modified PDCCH configuration; and
processing the DCI according to the modified PDCCH configuration,
wherein the indication of the modified PDCCH configuration for enhanced coverage includes at least one of:
an indication of whether to monitor for a DCI with a reduced payload size compared to legacy DCI, the DCI with the reduced payload size excludes one or more DCI fields included in the legacy DCI, one or more bits of one or more DCI fields included in the legacy DCI, or a combination thereof,
an indication of whether to use at least one of a first de-interleaving pattern or a first frozen bit repetition pattern associated with the legacy DCI or at least one of a second de-interleaving pattern or a second frozen bit repetition pattern associated with the DCI in which one or more low priority bits of the DCI are mapped to one or more less reliable positions as compared to one or more high priority bits of the DCI, one or more values corresponding to the one or more low priority bits are indicated in system information or in a radio resource control message, or
an indication of whether to use a first radio network temporary identifier (RNTI) having a first bit length to decode the DCI or a second RNTI having a second bit length, longer than the first bit length, to decode the DCI.
2. The method of claim 1 , wherein the indication of the modified PDCCH configuration for enhanced coverage is included in system information, a radio resource control message, or a combination thereof.
3. The method of claim 1 , wherein the indication of the modified PDCCH configuration for enhanced coverage further includes an indication of a DCI format for the DCI with the reduced payload size.
4. The method of claim 1 , wherein the at least one of the second de-interleaving pattern or the second frozen bit repetition pattern is specific to at least one of a DCI format, a DCI payload size, or a radio network temporary identifier associated with the DCI.
5. The method of claim 1 , wherein the one or more low priority bits include at least one of a reserved bit, a padding bit, an unused bit, a bit mapped to a radio network temporary identifier, a bit mapped to a search space set configuration, or a combination thereof.
6. The method of claim 1 , wherein the at least one of the second de-interleaving pattern or the second frozen bit repetition pattern is indicated in a radio resource control message.
7. The method of claim 1 , wherein the one or more values corresponding to the one or more low priority bits are determined based at least in part on a radio network temporary identifier, a search space set configuration, or a combination thereof.
8. The method of claim 1 , wherein the first bit length is 16 bits and the second bit length is greater than 16 bits.
9. The method of claim 1 , wherein the indication of the modified PDCCH configuration for enhanced coverage includes an indication of the second bit length.
10. The method of claim 1 , wherein the indication of the modified PDCCH configuration for enhanced coverage further includes an indication of whether to test multiple scrambling identifiers when processing the DCI or a demodulation reference signal associated with the DCI.
11. The method of claim 10 , wherein a first scrambling identifier indicates a first value for a bit excluded from the DCI if a cyclic redundancy check of the DCI succeeds using the first scrambling identifier, and wherein a second scrambling identifier indicates a second value for the bit if the cyclic redundancy check of the DCI succeeds using the second scrambling identifier.
12. The method of claim 1 , wherein the indication of the modified PDCCH configuration for enhanced coverage further includes an indication of whether to use a linear scrambling scheme for the DCI or a demodulation reference signal (DMRS) associated with the DCI or a non-linear scrambling scheme for the DCI or the DMRS associated with the DCI.
13. The method of claim 1 , wherein the UE is a low tier UE or a high tier UE leveraging the modified PDCCH configuration.
14. A method of wireless communication performed by a network node, comprising:
transmitting an indication of a modified physical downlink control channel (PDCCH) configuration for enhanced coverage; and
transmitting downlink control information (DCI) configured according to the modified PDCCH configuration,
wherein the indication of the modified PDCCH configuration for enhanced coverage includes at least one of:
an indication of whether to monitor for a DCI with a reduced payload size compared to legacy DCI, the DCI with the reduced payload size excludes one or more DCI fields included in the legacy DCI, one or more bits of one or more DCI fields included in the legacy DCI, or a combination thereof,
an indication of whether to use at least one of a first de-interleaving pattern or a first frozen bit repetition pattern associated with the legacy DCI or at least one of a second de-interleaving pattern or a second frozen bit repetition pattern associated with the DCI in which one or more low priority bits of the DCI are mapped to one or more less reliable positions as compared to one or more high priority bits of the DCI, one or more values corresponding to the one or more low priority bits are indicated in system information or in a radio resource control message, or
an indication of whether to use a first radio network temporary identifier (RNTI) having a first bit length to decode the DCI or a second RNTI having a second bit length, longer than the first bit length, to decode the DCI.
15. The method of claim 14 , wherein the indication of the modified PDCCH configuration for enhanced coverage further includes an indication of whether to test multiple scrambling identifiers when processing the DCI or a demodulation reference signal associated with the DCI.
16. The method of claim 14 , wherein the indication of the modified PDCCH configuration for enhanced coverage further includes an indication of whether to use a linear scrambling scheme for the DCI or a demodulation reference signal (DMRS) associated with the DCI or a non-linear scrambling scheme for the DCI or the DMRS associated with the DCI.
17. The method of claim 14 , wherein the indication of the modified PDCCH configuration for enhanced coverage is included in system information, a radio resource control message, or a combination thereof.
18. The method of claim 14 , wherein the indication of the modified PDCCH configuration for enhanced coverage further includes an indication of a DCI format for the DCI with the reduced payload size.
19. The method of claim 14 , wherein:
the at least one of the second de-interleaving pattern or the second frozen bit repetition pattern is specific to at least one of a DCI format, a DCI payload size, or a radio network temporary identifier associated with the DCI,
the one or more low priority bits include at least one of a reserved bit, a padding bit, an unused bit, a bit mapped to a radio network temporary identifier, a bit mapped to a search space set configuration, or a combination thereof, or
the at least one of the second de-interleaving pattern or the second frozen bit repetition pattern is indicated in a radio resource control message.
20. A user equipment (UE) for wireless communication, comprising:
a memory; and
one or more processors coupled to the memory, the memory comprising instructions executable by the one or more processors to cause the UE to:
receive an indication of a modified physical downlink control channel (PDCCH) configuration for enhanced coverage;
receive downlink control information (DCI) configured according to the modified PDCCH configuration; and
process the DCI according to the modified PDCCH configuration,
wherein the indication of the modified PDCCH configuration for enhanced coverage includes at least one of:
an indication of whether to monitor for a DCI with a reduced payload size compared to legacy DCI, the DCI with the reduced payload size excludes one or more DCI fields included in the legacy DCI, one or more bits of one or more DCI fields included in the legacy DCI, or a combination thereof,
an indication of whether to use at least one of a first de-interleaving pattern or a first frozen bit repetition pattern associated with the legacy DCI or at least one of a second de-interleaving pattern or a second frozen bit repetition pattern associated with the DCI in which one or more low priority bits of the DCI are mapped to one or more less reliable positions as compared to one or more high priority bits of the DCI, one or more values corresponding to the one or more low priority bits are indicated in system information or in a radio resource control message, or
an indication of whether to use a first radio network temporary identifier (RNTI) having a first bit length to decode the DCI or a second RNTI having a second bit length, longer than the first bit length, to decode the DCI.
21. The UE of claim 20 , wherein the indication of the modified PDCCH configuration for enhanced coverage further includes an indication of whether to test multiple scrambling identifiers when processing the DCI or a demodulation reference signal associated with the DCI.
22. The UE of claim 20 , wherein the indication of the modified PDCCH configuration for enhanced coverage is included in system information, a radio resource control message, or a combination thereof.
23. The UE of claim 20 , wherein the indication of the modified PDCCH configuration for enhanced coverage further includes an indication of a DCI format for the DCI with the reduced payload size.
24. The UE of claim 20 , wherein:
the at least one of the second de-interleaving pattern or the second frozen bit repetition pattern is specific to at least one of a DCI format, a DCI payload size, or a radio network temporary identifier associated with the DCI,
the one or more low priority bits include at least one of a reserved bit, a padding bit, an unused bit, a bit mapped to a radio network temporary identifier, a bit mapped to a search space set configuration, or a combination thereof, or
the at least one of the second de-interleaving pattern or the second frozen bit repetition pattern is indicated in a radio resource control message.
25. The UE of claim 20 , wherein:
the first bit length is 16 bits and the second bit length is greater than 16 bits, or
the indication of the modified PDCCH configuration for low tier UEs enhanced coverage includes an indication of the second bit length.
26. The UE of claim 20 , wherein the UE is a low tier UE or a high tier UE leveraging the modified PDCCH configuration.
27. A network node for wireless communication, comprising:
a memory; and
one or more processors coupled to the memory, the memory comprising instructions executable by the one or more processors to cause the network node to:
transmit an indication of a modified physical downlink control channel (PDCCH) configuration for enhanced coverage; and
transmit downlink control information (DCI) configured according to the modified PDCCH configuration,
wherein the indication of the modified PDCCH configuration for enhanced coverage includes at least one of:
an indication of whether to monitor for a DCI with a reduced payload size compared to legacy DCI, the DCI with the reduced payload size excludes one or more DCI fields included in the legacy DCI, one or more bits of one or more DCI fields included in the legacy DCI, or a combination thereof,
an indication of whether to use at least one of a first de-interleaving pattern or a first frozen bit repetition pattern associated with the legacy DCI or at least one of a second de-interleaving pattern or a second frozen bit repetition pattern associated with the DCI in which one or more low priority bits of the DCI are mapped to one or more less reliable positions as compared to one or more high priority bits of the DCI, one or more values corresponding to the one or more low priority bits are indicated in system information or in a radio resource control message, or
an indication of whether to use a first radio network temporary identifier (RNTI) having a first bit length to decode the DCI or a second RNTI having a second bit length, longer than the first bit length, to decode the DCI.
28. The network node of claim 27 , wherein the indication of the modified PDCCH configuration for enhanced coverage is included in system information, a radio resource control message, or a combination thereof.
29. The network node of claim 27 , wherein the indication of the modified PDCCH configuration for enhanced coverage further includes an indication of a DCI format for the DCI with the reduced payload size.
30. The network node of claim 27 , wherein the indication of the modified PDCCH configuration for enhanced coverage further includes an indication of whether to test multiple scrambling identifiers when processing the DCI or a demodulation reference signal associated with the DCI.