TECHNICAL FIELD

The present disclosure relates to a terminal and a communication method.

BACKGROUND ART

With the spread of services using mobile broadband in recent years, data traffic in mobile communication has continued to increase exponentially, and looking forward there is a pressing need to expand data transmission capacities. Furthermore, in the future, dramatic developments are anticipated for the IoT (Internet of Things) in which all “things” are connected via the Internet. To support the diversification of services by means of the IoT, dramatic advancements are needed not only for data transmission capacity but also for various requirements such as low latency and communication area (coverage). With this background, progress is being made in the technical development/standardization of the fifth-generation mobile communication system (5G), which considerably improves performance and function compared to the fourth-generation mobile communication system (4G).

In the 3GPP (3rd Generation Partnership Project), in the standardization of 5G, progress is being made in the technical development of new radio access technology (NR: new RAT) that does not always have backward compatibility with LTE (Long Term Evolution)-Advanced.

In NR, similar to LTE, consideration is being given to a terminal (UE: user equipment) transmitting a response signal (ACK/NACK: acknowledgment/negative acknowledgment) indicating an error detection result for downlink data, channel state information (CSI) for a downlink, and a radio resource allocation request (SR: scheduling request) for an uplink, to a base station (eNB or gNB) using an uplink control channel (PUCCH: physical uplink control channel).

Furthermore, in NR, a terminal is able to carry out a PUCCH-PUSCH simultaneous transmission (a simultaneous PUCCH and PUSCH) in which a PUCCH and an uplink channel (PUSCH: physical uplink shared channel) for transmitting data are transmitted at the same time and in the same slot (see NPL 4 and 5).

CITATION LIST

Non Patent Literature

NPL 1: 3GPP TS 36.211 V13.4.0, “Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation (Release 13)”, December 2016.NPL 2: 3GPP TS 36.213 V13.4.0, “Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Layer Procedures (Release 13)”, December 2016.NPL 3: 3GPP TS 36.211 V13.4.0, “Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation (Release 13)”, December 2016.NPL 4: Chairman's note, RAN1 #87, November 2016.NPL 5: Chairman's note, RAN1 NR #NR Adhoc (Spokane's meeting), January 2017.NPL 6: R1-1700174, “Discussion on Multiplexing of Short PUCCH and UL Data”, MediaTek, January 2017.

SUMMARY OF INVENTION

With a PUCCH-PUSCH simultaneous transmission, there are cases where the power spectrum density (PSD) is different between the PUCCH and PUSCH. If the difference in the PSD between the PUCCH and PUSCH exceeds a limit (hereinafter referred to as the “permitted difference”) for the performance of an RF (radio frequency) circuit provided in a terminal, distortion occurs in signals and the transmission quality deteriorates. In particular, in NR, consideration is being given to allocating frequencies of a wider band compared to LTE-Advanced to improve transmission speed. Therefore, in NR, the effect on transmission quality due to the permitted difference for PSD becomes more notable compared to LTE-Advanced.

An embodiment of the present disclosure facilitates providing a terminal and a communication method with which it is possible for a PUCCH-PUSCH simultaneous transmission to be carried out while preventing a deterioration in transmission quality due to the permitted difference for PSD.

A terminal according to an embodiment of the present disclosure is provided with: a circuit that, in a slot having allocated thereto both an uplink control channel (PUCCH) and an uplink channel (PUSCH) that includes uplink data, in a case where a difference between a power spectrum density (PSD) of the PUCCH and the PSD of the PUSCH is greater than a threshold value, drops a symbol of the PUSCH in a transmission interval for the PUSCH overlapping with a transmission interval for the PUCCH; and a transmitter that transmits at least the PUCCH in the slot.

A terminal according to an embodiment of the present disclosure is provided with: a circuit that, in a slot having allocated thereto both an uplink control channel (PUCCH) and an uplink channel (PUSCH) that includes uplink data, in a case where a difference between a power spectrum density (PSD) of the PUCCH and the PSD of the PUSCH is greater than a threshold value, drops a portion of resources of frequency resources to which the PUSCH is allocated in a transmission interval for the PUSCH overlapping with a transmission interval for the PUCCH; and a transmitter that transmits the PUCCH, and the PUSCH for which the portion of a frequency band has been dropped, in the slot.

A terminal according to an embodiment of the present disclosure is provided with: a circuit that, in a slot having allocated thereto both an uplink control channel (PUCCH) and an uplink channel (PUSCH) that includes uplink data, in a case where a difference between a power spectrum density (PSD) of the PUCCH and the PSD of the PUSCH is greater than a threshold value, changes a transmission format of the PUCCH; and a transmitter that transmits the PUCCH obtained after the transmission format has been changed, and the PUSCH, in the slot.

A communication method according to an embodiment of the present disclosure includes: in a slot having allocated thereto both an uplink control channel (PUCCH) and an uplink channel (PUSCH) that includes uplink data, in a case where a difference between a power spectrum density (PSD) of the PUCCH and the PSD of the PUSCH is greater than a threshold value, dropping a symbol of the PUSCH in a transmission interval for the PUSCH overlapping with a transmission interval for the PUCCH; and transmitting at least the PUCCH in the slot.

A communication method according to an embodiment of the present disclosure includes: in a slot having allocated thereto both an uplink control channel (PUCCH) and an uplink channel (PUSCH) that includes uplink data, in a case where a difference between a power spectrum density (PSD) of the PUCCH and the PSD of the PUSCH is greater than a threshold value, dropping a portion of resources of frequency resources to which the PUSCH is allocated in a transmission interval for the PUSCH overlapping with a transmission interval for the PUCCH; and transmitting the PUCCH, and the PUSCH for which the portion of a frequency band has been dropped, in the slot.

A communication method according to an embodiment of the present disclosure includes: in a slot having allocated thereto both an uplink control channel (PUCCH) and an uplink channel (PUSCH) that includes uplink data, in a case where a difference between a power spectrum density (PSD) of the PUCCH and the PSD of the PUSCH is greater than a threshold value, changing a transmission format of the PUCCH; and transmitting the PUCCH obtained after the transmission format has been changed, and the PUSCH, in the slot.

It should be noted that general or specific embodiments hereof may be realized by a system, a method, an integrated circuit, a computer program, or a recording medium, and may be realized by an arbitrary combination of a system, a device, a method, an integrated circuit, a computer program, and a recording medium.

According to an embodiment of the present disclosure, it is possible for a PUCCH-PUSCH simultaneous transmission to be carried out while preventing a deterioration in transmission quality due to the permitted difference for PSD.

Additional benefits and advantages in an embodiment of the present disclosure will be made apparent from the specification and drawings. The benefits and/or advantages may each be provided by several of the embodiments and the features disclosed in the specification and drawings, and need not all be provided in order to obtain one or more of the same features.

