US-12621811-B2 - Terminal, base station, and radio communication method

US12621811B2US 12621811 B2US12621811 B2US 12621811B2US-12621811-B2

Abstract

A terminal comprises: a reception unit that receives a first control information by a first control channel on a first carrier and a second control information by a second control channel on a second carrier; and a control unit that controls a reception of the second control channel based on the first control information, and controls a communication of data based on the second control information.

Inventors

Yuki Takahashi
Shohei Yoshioka
Masaya Okamura
Shinya Kumagai
Satoshi Nagata

Assignees

NTT DOCOMO, INC.

Dates

Publication Date: 20260505
Application Date: 20201225

Claims (5)

1 . A terminal comprising: a receiver that receives a first control information by a first control channel on a first carrier and a second control information by a second control channel on a second carrier, a subcarrier spacing of the second carrier being greater than a subcarrier spacing of the first carrier, the first carrier belonging to a first frequency range, the second carrier belonging to a second frequency range; and a processor that controls the reception of the second control information by the second control channel on the second carrier based on the first control information received on the first carrier, and controls communication of data by a data channel on the second carrier based on the second control information received on the second carrier.
2 . The terminal according to claim 1 , wherein the processor specifies at least one of a time domain resource and a frequency domain resource of the second control channel based on the first control information, or specifies at least one of a time domain resource and a frequency domain resource of the second control channel based on a configuration of a higher layer.
3 . The terminal according to claim 1 , wherein the first control information includes an information element for specifying at least one of a number of control channel elements allocable to the second control channel and a format of the second control channel.
4 . A base station comprising: a transmitter that transmits a first control information by a first control channel on a first carrier and a second control information by a second control channel on a second carrier, a subcarrier spacing of the second carrier being greater than a subcarrier spacing of the first carrier, the first carrier belonging to a first frequency range, the second carrier belonging to a second frequency range; and a processor that controls the transmission of the second control information by the second control channel on the second carrier based on the first control information received on the first carrier, and controls communication of data based by a data channel on the second carrier on the second control information received on the second carrier.
5 . A radio communication method comprising the steps of: receiving a first control information by a first control channel on a first carrier and a second control information by a second control channel on a second carrier, a subcarrier spacing of the second carrier being greater than a subcarrier spacing of the first carrier, the first carrier belonging to a first frequency range, the second carrier belonging to a second frequency range; controlling the reception of the second control information by the second control channel on the second carrier based on the first control information received on the first carrier; and controlling communication of data by a data channel on the second carrier based on the second control information received on the second carrier.

Description

TECHNICAL FIELD The present disclosure relates to a terminal, a base station, and a radio communication method for executing radio communication, and more particularly, to a terminal, a base station, and a radio communication method corresponding to cross-carrier scheduling. BACKGROUND ART The 3rd Generation Partnership Project (3GPP) specifies 5th generation mobile communication system (5G, also called New Radio (NR) or Next Generation (NG), further, a succeeding system called Beyond 5G, 5G Evolution or 6G is being specified. Release 15 and Release 16 (NR) of the 3 GPP specify operation in a band that includes multiple frequency ranges, specifically, FR 1 (410 MHz to 7.125 GHz) and FR 2 (24.25 GHz to 52.6 GHz). NR beyond 52.6 GHz to 71 GHz is also under consideration (Non-Patent Literature 1). In addition, Beyond 5G, 5G Evolution, or 6 G (Release-18 and later) aims to support frequencies above 71 GHz. CITATION LIST Non-Patent Literature Non-Patent Literature 1 “New WID on Extending current NR operation to 71 GHz”, RP-193229, 3 GPP TSG RAN Meeting #86, 3 GPP, December 2019 SUMMARY OF INVENTION When a frequency band different from that of the FR1 and FR2, such as a high frequency band exceeding 52.6 GHz, is used, a large (wide) subcarrier interval (SCS) is assumed to be applied in order to support stable radio communication when a terminal (User Equipment, UE) moves at a high speed, thereby shortening the symbol time. In a carrier to which a large SCS is applied, channel estimation (CE) of a control channel (For example, PDCCH (Physical Downlink Control Channel)) is limited, so that the number of CCEs (s) (Control Channel Element (s)) that can be assigned to the control channel is reduced. In order to solve such a problem, cross-carrier scheduling using two or more carriers can be considered, but the inventors have found, as a result of careful examination, that the number of schedulable data decreases due to the difference in symbol times of two or more carriers. Accordingly, the following disclosure has been made in view of such a situation, and it is an object of the present invention to provide a terminal, a base station, and a radio communication method capable of appropriately coping with cross-carrier scheduling. An aspect of the present disclosure is a terminal comprising: a reception unit that receives a first control information by a first control channel on a first carrier and a second control information by a second control channel on a second carrier; and a control unit that controls a reception of the second control channel based on the first control information, and controls a communication of data based on the second control information. An aspect of the present disclosure is a base station comprising: a transmission unit that transmits a first control information by a first control channel on a first carrier and a second control information by a second control channel on a second carrier; and a control unit that controls a transmission of the second control information based on the first control information, and controls communication of data based on the second control information. An aspect of the present disclosure is a radio communication method comprising the steps of: (A) receiving a first control information by a first control channel on a first carrier; and (B) receiving a second control information via a second control channel on a second carrier; wherein the step (A) includes a step of controlling the reception of the second control channel based on the first control information; and the step (B) includes a step of controlling communication of data based on the second control information. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an overall schematic diagram of a radio communication system 10. FIG. 2 is a diagram illustrating the frequency range used in radio communication system 10. FIG. 3 shows an exemplary configuration of a radio frame, subframe, and slot used in a radio communication system 10. FIG. 4 is a functional block diagram of the UE 200. FIG. 5 is a functional block diagram of the gNB 100. FIG. 6 is a diagram for illustrating two-step control channel indication. FIG. 7 is a sequence diagram showing an example of operation. FIG. 8 is a diagram for explaining the two-step control channel indication according to the first modification. FIG. 9 is a diagram for explaining the two-step control channel indication according to the first modification. FIG. 10 is a diagram for explaining the 2-step control channel indication according to the modification 1. FIG. 11 is a diagram for explaining the 2-step control channel indication according to the modification 1. FIG. 12 is a diagram for explaining the 2-step control channel indication according to the modification 1. FIG. 13 is a diagram for explaining the 2-step control channel indication according to the modification 2. FIG. 14 is a diagram for explaining the 2-step control channel indication according to the modification 2. FIG