Method for dynamically allocating resources to frequency band of short TTI and device using same
A method and device for dynamically allocating resources to a frequency band of a short transmission time interval (TTI) in a wireless communication system is provided. Specifically, a plurality of first downlink channels and a second downlink channel included in a subframe corresponding to one TTI are received, wherein the plurality of first downlink channels are received during sTTIs and the second downlink channel is received during the TTI. The plurality of first downlink channels are sequentially received. The plurality of first downlink channels are demodulated using control information included in a downlink control information (DCI) used for the second downlink channel and an RRC message. The control information and RRC message indicate frequency resources for the plurality of first downlink channels.
1. A method for receiving, by a user equipment (UE), short downlink (DL) channels including a first short DL channel and a second short DL channel in a wireless communication system, the method comprising:
receiving a reference DL channel including a Physical Downlink Control Channel (PDCCH) from a base station (BS) during a transmission time interval (TTI),
wherein downlink control information (DCI) is received through the PDCCH; and
receiving the first short DL channel during a first short TTI (sTTI) and the second short DL channel during a second sTTI based on the DCI,
wherein the first sTTI and the second sTTI are included in the TTI,
wherein the DCI includes information on a first frequency resource for the first short DL channel and the second short DL channel,
wherein the first short DL channel includes a first short Physical Downlink Control Channel (sPDCCH) and a first short Physical Downlink Shared Channel (sPDSCH) scheduled using the first sPDCCH,
wherein the second short DL channel includes a second sPDCCH and a second sPDSCH scheduled using the second sPDCCH,
wherein the first sPDCCH and the second sPDCCH are allocated to the first frequency resource,
wherein the PDCCH is allocated to a second frequency resource different from the first frequency resource,
wherein a first symbol of each of the first short DL channel and the second short DL channel includes a short Physical Control Format Indicator Channel (sPCFICH), wherein each sPCFICH indicates a resources region used for transmitting a control region for each of the first short DL channel and the second short DL channel, and
wherein the sPCFICH is arranged only in a first Orthogonal Frequency Division Multiplexing (OFDM) symbol among the plurality of OFDM symbols of odd numbered sTTIs of the first and second sTTIs.
2. The method of claim 1 , wherein the reference DL channel further includes a Physical Downlink Shared Channel (PDSCH) scheduled using the PDCCH.
3. The method of claim 1 , further comprising:
receiving a radio resource control (RRC) message from the BS, wherein the RRC message includes allocation information on the first short DL channel and the second short DL channel,
wherein the DCI includes information on whether the first frequency resource for the first short DL channel and the second short DL channel in a current subframe are allocated in a subsequent subframe, and
wherein the RRC message includes information on a scheme for allocating the first short DL channel and the second short DL channel to the first frequency resource.
4. The method of claim 3 , wherein the RRC message includes information on an uplink resource region that is accessed in a contention-based manner.
5. The method of claim 3 , wherein the DCI includes information on an uplink resource region that is accessed in a contention-based manner.
6. The method of claim 3 , wherein the RRC message includes information on time resources for the first sTTI and the second sTTI.
7. The method of claim 1 , wherein at least one symbol among a plurality of symbols for transmitting each of the first short DL channel and the second short DL channel includes a cell-specific reference signal (CRS).
8. The method of claim 1 , wherein each of the first short DL channel and the second short DL channel is received using the same number of symbols.
9. A user equipment (UE) for receiving short downlink (DL) channels including a first short DL channel and a second short DL channel in a wireless communication system, UE comprising:
a transmitter and a receiver; and
a processor operatively coupled to the transmitter and receiver, wherein the processor is configured to:
control the receiver to receive a reference DL channel including a Physical Downlink Control Channel (PDCCH) from a base station (BS) during a transmission time interval (TTI),
wherein downlink control information (DCI) is received through the PDCCH; and
control the receiver to receive the first short DL channel during a first short TTI (sTTI) and the second short DL channel during a second sTTI based on the DCI,
wherein the first sTTI and the second sTTI are included in the TTI,
wherein the DCI includes information on a first frequency resource for the first short DL channel and the second short DL channel,
wherein the first short DL channel includes a first short Physical Downlink Control Channel (sPDCCH) and a first short Physical Downlink Shared Channel (sPDSCH) scheduled using the first sPDCCH,
wherein the second short DL channel includes a second sPDCCH and a second sPDSCH scheduled using the second sPDCCH,
wherein the first sPDCCH and the second sPDCCH are allocated to the first frequency resource,
wherein the PDCCH is allocated to a second frequency resource different from the first frequency resource,
wherein a first symbol of each of the first short DL channel and the second short DL channel includes a short Physical Control Format Indicator Channel (sPCFICH), wherein each sPCFICH indicates a resources region used for transmitting a control region for each of the first short DL channel and the second short DL channel, and
the sPCFICH is arranged only in a first Orthogonal Frequency Division Multiplexing (OFDM) symbol among the plurality of OFDM symbols of odd numbered sTTIs of the first and second sTTIs.