User terminal and radio communication method
摘要
說明書
The sTTI duration to be applied to SR transmission may be reported by higher layer signaling (for example, RRC signaling, MAC signaling (for example, MAC control elements (MAC CEs)), by broadcast information (the MIB (Master Information Block). SIBs (System Information Blocks), etc.), by physical layer signaling (for example, DCI), or by combining these.
For example, an sTTI duration that is semi-statically configured by higher layer may be used in the following cases:
(1) When only an SR is transmitted;
(2) When, using an SR resource, a one-bit or two-bit HARQ-ACK in response to the sPDSCH is multiplexed and transmitted with an SR (as in LTE PUCCH format 1a/1b); and
(3) When periodic CSI (P-CSI) transmission is supported in sTTIs, and, using a P-CSI resource, P-CSI is multiplexed and transmitted with an SR (as in LTE PUCCH format 4/5).
Also, an sTTI duration that is dynamically reported in physical layer signaling may be used when, using an HARQ-ACK resource, an HARQ-ACK is multiplexed and transmitted with an SR (as in LTE PUCCH format 3). In this case, the sTTI duration in the sPUCCH in which an HARQ-ACK is transmitted in response to the sPDSCH may be dynamically changed based on, for example, the payload size, the coverage and so on.
As explained above, according to embodiment 1.2, SRs are configured only in the sPUCCH, so that it is possible to transmit SRs in a short time.
In embodiment 1.3, SRs are configured in both the PUCCH and the sPUCCH. Embodiment 1.3 can be roughly divided into three, depending how SR procedures are controlled (embodiments 1.3.1 to 1.3.3).
