User terminal and radio communication method
摘要
說明書
A UE in which the short TTI is configured would use channels of shorter time units than existing data and control channels. In LTE and NR, for example, as shortened channels to be transmitted and/or received in short TTIs a shortened downlink control channel (sPDCCH: shortened PDCCH), a shortened downlink data channel (sPDSCH: shortened PDSCH), a shortened uplink control channel (sPUCCH: shortened PUCCH), and a shortened downlink data channel (sPUSCH: shortened PUSCH) and so on are under research.
Note that, although examples will be shown in this specification where two short TTIs (for example, the short TTI duration=seven symbols long) are included in a long TTI (for example, the long TTI duration=1 ms), the format of each TTI is not limited to this. For example, the long TTI and/or the short TTI may have different time durations, and short TTIs of a plurality of short TTI durations may be used in one long TTI. Also, any number of short TTIs may be contained in one long TTI. In addition, the long TTI and the short TTI may be constituted by relatively prime numbers of symbols. For example, the long TTI may be fourteen symbols long, and the short TTI may be three symbols long. In this case, the long TTI duration is not formed even of the short TTI, having the same duration, is multiplied by an integer.
Now, in existing LTE (for example, LTE Rel. 9 to 13), a UE feeds back uplink control information (UCI) to a device (for example, a base station) on the network side. The base station performs data retransmission control, scheduling control and so on for the UE based on the received UCI.
