Method and apparatus for supporting multiple TTIs, multiple subcarrier spacings, or multiple processing times in wireless communication system
View Patent ↗A method of transmitting uplink (UL) control information for a user equipment (UE) for supporting a plurality of TTI lengths, a plurality of subcarrier spacing, or a plurality of processing times in a wireless communication system is performed by the UE and includes mapping the UL control information to a radio resource in a TTI including two or three symbols, the UL control information including HARQ-ACK, a rank indicator (RI), a channel quality indicator (CQI), or a precoding matrix indicator (PMI), and transmitting the UL control information to a base station, wherein, when there is no symbol to which a DMRS is mapped in the TTI, HARQ-ACK is mapped to a first symbol in the TTI in descending order from a highest frequency index resource element (RE) and the RI is mapped to the other symbol in the TTI in descending order from a highest frequency index RE.
1. A method of transmitting uplink (UL) control information by a terminal in a wireless communication system, the method comprising:
mapping, in both a time domain and a frequency domain, the UL control information to a radio resource in a transmission time interval (TTI), the UL control information comprising (i) hybrid automatic retransmission request-acknowledgement/non-acknowledgement (HARQ-ACK), and (ii) a rank indicator (RI); and
transmitting the UL control information to a base station (BS), using the radio resource to which the UL control information is mapped in the TTI,
wherein mapping, in both the time domain and the frequency domain, the UL control information to the radio resource in the TTI comprises:
based on (i) the TTI having a time duration of two symbols, (ii) a demodulation reference signal (DMRS) not being mapped to any of the two symbols in the TTI, and (iii) the DMRS being mapped to another TTI that is subsequent in time to the TTI:
mapping the HARQ-ACK to an initial symbol among the two symbols in the TTI, in descending order of frequency from a resource element (RE) of a highest frequency index for the initial symbol; and
mapping the RI to a last symbol among the two symbols in the TTI, in descending order of frequency from an RE of a highest frequency index for the last symbol.
2. The method according to claim 1 , wherein mapping, in both the time domain and the frequency domain, the UL control information to the radio resource in the TTI further comprises:
based on (i) the TTI having a time duration of three symbols, and (ii) the DMRS being mapped to an initial symbol among the three symbols in the TTI:
mapping both the HARQ-ACK and the RI to a middle symbol among the three symbols in the TTI, and mapping a sounding reference signal (SRS) to a last symbol among the three symbols in the TTI,
wherein the HARQ-ACK and the RI are mapped to different frequencies for the middle symbol.
3. The method according to claim 1 , wherein the terminal is configured to support a plurality of TTI time durations and a plurality of subcarrier spacing, and
wherein a maximum number of coded symbols to which the UL control information is to be mapped is limited by a product of (i) a number of symbols to which the UL control information is mapped and (ii) a number of subcarriers corresponding to a channel to which the UL control information is to be transmitted.
4. The method according to claim 3 , wherein the number of symbols to which the UL control information is mapped is different for each of the plurality of TTI time durations.
5. The method according to claim 1 , wherein transmitting the UL control information to the BS, using the radio resource to which the UL control information is mapped in the TTI, comprises:
transmitting the UL control information in an UL data channel with the TTI having a duration less than 1 ms.
6. The method according to claim 1 , wherein, based on (i) the TTI having a time duration of two symbols, and (ii) the DMRS being mapped to one of the two symbols in the TTI:
the DMRS is mapped to the one of the two symbols using fewer than all resource blocks (RBs) in the frequency domain.
7. The method according to claim 6 , wherein mapping, in both the time domain and the frequency domain, the UL control information to the radio resource in the TTI further comprises:
based on (i) the TTI having a time duration of two symbols, and (ii) the DMRS being mapped to one of the two symbols using fewer than all RBs in the frequency domain:
mapping the HARQ-ACK or the RI to the other of the two symbols using only a resource element (RE) having a same frequency index as an RE to which the DMRS is mapped in the frequency domain.
8. A terminal configured to transmit uplink (UL) control information in a wireless communication system, the terminal comprising:
a receiver and a transmitter;
at least one processor; and
at least one computer memory operably connectable to the at least one processor and storing instructions that, when executed by the at least one processor, perform operations comprising:
mapping, in both a time domain and a frequency domain, the UL control information to a radio resource in a transmission time interval (TTI), the UL control information comprising (i) hybrid automatic retransmission request-acknowledgement/non-acknowledgement (HARQ-ACK), and (ii) a rank indicator (RI); and
transmitting the UL control information to a base station (BS), using the radio resource to which the UL control information is mapped in the TTI,
wherein mapping, in both the time domain and the frequency domain, the UL control information to the radio resource in the TTI comprises:
based on (i) the TTI having a time duration of two symbols, (ii) a demodulation reference signal (DMRS) not being mapped to any of the two symbols in the TTI, and (iii) the DMRS being mapped to another TTI that is subsequent in time to the TTI:
mapping the HARQ-ACK to an initial symbol among the two symbols in the TTI, in descending order of frequency from a resource element (RE) of a highest frequency index for the initial symbol; and
mapping the RI to a last symbol among the two symbols in the TTI, in descending order of frequency from an RE of a highest frequency index for the last symbol.
9. The terminal according to claim 8 , wherein mapping, in both the time domain and the frequency domain, the UL control information to the radio resource in the TTI further comprises:
based on (i) the TTI having a time duration of three symbols, and (ii) the DMRS being mapped to an initial symbol among the three symbols in the TTI:
mapping both the HARQ-ACK and the RI to a middle symbol among the three symbols in the TTI, and mapping a sounding reference signal (SRS) to a last symbol among the three symbols in the TTI,
wherein the HARQ-ACK and the RI are mapped to different frequencies for the middle symbol.
10. The terminal according to claim 8 , wherein the terminal is configured to support a plurality of TTI time durations and a plurality of subcarrier spacing, and
wherein a maximum number of coded symbols to which the UL control information is to be mapped is limited by a product of (i) a number of symbols to which the UL control information is mapped, and (ii) a number of subcarriers corresponding to a channel to which the UL control information is to be transmitted.
11. The terminal according to claim 10 , wherein the number of symbols to which the UL control information is mapped is different for each of the plurality of TTI time durations.
12. The terminal according to claim 8 , wherein transmitting the UL control information to the BS, using the radio resource to which the UL control information is mapped in the TTI, comprises:
transmitting the UL control information in an UL data channel with the TTI having a shorter length than 1 ms.
13. The terminal according to claim 8 , wherein, based on (i) the TTI having a time duration of two symbols, and (ii) the DMRS being mapped to one of the two symbols in the TTI:
the DMRS is mapped to one of the two symbols using fewer than all resource blocks (RBs) in the frequency domain.
14. The terminal according to claim 13 , wherein mapping, in both the time domain and the frequency domain, the UL control information to the radio resource in the TTI further comprises:
based on (i) the TTI having a time duration of two symbols, and (ii) the DMRS being mapped to one of the two symbols using fewer than all RBs in the frequency domain:
mapping the HARQ-ACK or the RI to the other of the two symbols using only a resource element (RE) having a same frequency index as an RE to which the DMRS is mapped in the frequency domain.
15. A method of receiving uplink (UL) control information by a base station (BS) in a wireless communication system, the method comprising:
receiving, from a terminal, UL control information that is mapped, in both a time domain and a frequency domain, to a radio resource in a transmission time interval (TTI); and
determining, from the UL control information, (i) hybrid automatic retransmission request-acknowledgement/non-acknowledgement (HARQ-ACK), and (ii) a rank indicator (RI),
wherein, based on (i) the TTI having a time duration of two includes three symbols, iii) a demodulation reference signal (DMRS) not being mapped to any of the two symbols in the TTI, and (iii) the DMRS being mapped to another TTI that is subsequent in time to the TTI:
the HARQ-ACK is mapped to an initial symbol among the two symbols in the TTI, in descending order of frequency from a resource element (RE) of a highest frequency index for the initial symbol, and
the RI is mapped to a last symbol among the two symbols in the TTI, in descending order of frequency from an RE of a highest frequency index for the last symbol.
16. The method according to claim 1 , wherein the UL control information further comprises at least one of (iii) a channel quality indicator (CQI), or (iv) a precoding matrix indicator (PMI).
17. The terminal according to claim 8 , wherein the UL control information further comprises at least one of (iii) a channel quality indicator (CQI), or (iv) a precoding matrix indicator (PMI).