JP-7857201-B2 - Base station equipment, terminal equipment, and communication method

JP7857201B2JP 7857201 B2JP7857201 B2JP 7857201B2JP-7857201-B2

Inventors

橘田真
石倉勝利
竹花秀一
佐藤楓
金森耕一

Assignees

シャープ株式会社

Dates

Publication Date: 20260512
Application Date: 20220926

Claims (15)

A base station device capable of broadcast and unicast information communication, A transmitting and receiving unit that transmits a first signal via broadcast to a terminal device in an idle state (RRC_IDLE) and receives a second signal from the terminal device that includes negative response (NACK) information indicating a deterioration in communication quality based on the first signal, A determination unit that determines whether it is difficult to continue communication with the terminal device via broadcast based on the negative response information contained in the second signal, The system comprises a control unit which, when the determination unit determines that broadcast communication is difficult, instructs the transmitting/receiving unit to transmit a third signal including notification information for switching to unicast to the terminal device , The second signal is a preamble signal, The third signal is a preamble reception response signal, which is a response to the preamble signal, in the base station device.
The base station device according to claim 1 , wherein the determination unit determines, based on the number of times the second signal is received within a predetermined period, whether it is difficult to continue broadcast communication with the terminal device.
A base station device capable of broadcast and unicast information communication, A transmitting and receiving unit that transmits a first signal via broadcast to a terminal device in an idle state (RRC_IDLE) and receives a second signal from the terminal device that includes negative response (NACK) information indicating a deterioration in communication quality based on the first signal, A determination unit that determines whether it is difficult to continue communication with the terminal device via broadcast based on the negative response information contained in the second signal, When the determination unit determines that communication by broadcast is difficult, the control unit commands the transceiver to transmit a third signal, which includes notification information for switching to unicast, to the terminal device. It is equipped with, The base station device is such that the second and third signals are signals transmitted and received in a random access procedure.
A base station device capable of broadcast and unicast information communication, A transmitting and receiving unit that transmits a first signal via broadcast to a terminal device in an idle state (RRC_IDLE) and receives a second signal from the terminal device that includes negative response (NACK) information indicating a deterioration in communication quality based on the first signal, A determination unit that determines whether it is difficult to continue communication with the terminal device via broadcast based on the negative response information contained in the second signal, When the determination unit determines that communication by broadcast is difficult, the control unit commands the transceiver to transmit a third signal, which includes notification information for switching to unicast, to the terminal device. It is equipped with, The base station device is a Radio Resource Control (RRC) Setup Request signal, the second signal of which further includes information regarding the communication status between the base station device and the terminal device.
The base station apparatus according to claim 4 , wherein the third signal is an RRC connection setup signal (RRC Setup).
The base station device according to claim 4, wherein the determination unit determines whether it is difficult to continue broadcast communication with the terminal device based on the negative response information included in the second signal and information regarding the communication status between the base station device and the terminal device.
A base station device capable of broadcast and unicast information communication, A transmitting and receiving unit that transmits a first signal via broadcast to a terminal device in an idle state (RRC_IDLE) and receives a second signal from the terminal device that includes negative response (NACK) information indicating a deterioration in communication quality based on the first signal, A determination unit that determines whether it is difficult to continue communication with the terminal device via broadcast based on the negative response information contained in the second signal, When the determination unit determines that communication by broadcast is difficult, the control unit commands the transceiver to transmit a third signal, which includes notification information for switching to unicast, to the terminal device. It is equipped with, The second signal is a preamble signal, Based on the negative response information included in the second signal, the control unit commands the transceiver to transmit a preamble reception response signal to the terminal device as a fourth signal, which is a response to the preamble signal and includes a request for information regarding the communication status between the base station device and the terminal device. In response to the fourth signal, the transmitting/receiving unit receives an RRC Setup Request signal from the terminal device as a fifth signal, which further includes information regarding the communication status between the base station device and the terminal device. The determination unit determines, based on information regarding the communication status between the base station device and the terminal device included in the fifth signal, whether it is difficult to continue broadcast communication with the terminal device.
The base station device according to claim 7 , wherein the control unit, upon receiving the second signal once, causes the transmission/reception unit to transmit the fourth signal.
A terminal device capable of broadcast and unicast information communication, In an idle state (RRC_IDLE), a transceiver transmits a second signal to the base station device containing negative response (NACK) information for the first signal transmitted by broadcast from the base station device, and receives a third signal containing notification information for switching from broadcast to unicast. The system includes a control unit that, upon receiving the third signal, switches the communication method with the base station device from broadcast to unicast , The second signal is a preamble signal. The terminal device wherein the third signal is a preamble reception response signal, which is a response to the preamble signal .
The terminal device according to claim 9 , wherein the transmitting and receiving unit receives the third signal from the base station device when it has transmitted the second signal a predetermined number of times within a predetermined period.
A terminal device capable of broadcast and unicast information communication, In an idle state (RRC_IDLE), a transceiver transmits a second signal to the base station device containing negative response (NACK) information for the first signal transmitted by broadcast from the base station device, and receives a third signal containing notification information for switching from broadcast to unicast. A control unit that, upon receiving the third signal, switches the communication method with the base station device from broadcast to unicast. It is equipped with, The terminal device is one in which the second signal and the third signal are signals transmitted and received in a random access procedure.
A terminal device capable of broadcast and unicast information communication, In an idle state (RRC_IDLE), a transceiver transmits a second signal to the base station device containing negative response (NACK) information for the first signal transmitted by broadcast from the base station device, and receives a third signal containing notification information for switching from broadcast to unicast. A control unit that, upon receiving the third signal, switches the communication method with the base station device from broadcast to unicast. It is equipped with, The terminal device is a Radio Resource Control (RRC) Setup Request signal, the second signal of which further includes information regarding the communication status between the base station device and the terminal device.
The terminal device according to claim 12 , wherein the third signal is an RRC connection setup signal (RRC Setup).
A terminal device capable of broadcast and unicast information communication, In an idle state (RRC_IDLE), a transceiver transmits a second signal to the base station device containing negative response (NACK) information for the first signal transmitted by broadcast from the base station device, and receives a third signal containing notification information for switching from broadcast to unicast. A control unit that, upon receiving the third signal, switches the communication method with the base station device from broadcast to unicast. It is equipped with, The second signal is a preamble signal, After transmitting the second signal, the transmitting/receiving unit receives a fourth signal from the base station device, which is a preamble reception response signal that is a response to the preamble signal and includes a request for the communication status between the base station device and the terminal device. In response to the fourth signal, the transmitting/receiving unit transmits to the base station device a fifth signal, an RRC Setup Request signal, which further includes information regarding the communication status between the base station device and the terminal device. The transmitting and receiving unit is a terminal device that receives the third signal (RRC Setup) after transmitting the fifth signal.
The base station equipment broadcasts the first signal to terminal equipment in an idle state (RRC_IDLE), The terminal device transmits a second signal to the base station device that includes negative response (NACK) information indicating a deterioration in communication quality based on the first signal. The base station device determines, based on the negative response information included in the second signal, whether it is difficult to continue the broadcast communication with the terminal device. When it is determined that communication via broadcast is difficult, the base station device transmits a third signal containing information about switching to unicast to the terminal device. The terminal device, upon receiving the third signal, switches the communication method with the base station device from broadcast to unicast , A communication method wherein the second signal and the third signal are signals transmitted and received in a random access procedure .

Description

One aspect of the present invention relates to a base station device, a terminal device, and a communication method. In 3GPP (3rd Generation Partnership Project) Release 17, Multicast and Broadcast Service (MBS) is being considered for specification. Multicast mode requires communication during a network connection to support signaling and ACK/NACK feedback transmission. On the other hand, broadcast mode allows communication not only during a network connection but also during idle states. Furthermore, Patent Document 1 explores the transmission of ACK/NACK feedback via a preamble signal in the LTE (Long Term Evolution)_Idle state. Japanese Patent Publication No. 2017-123679 Conceptual diagram of a communication system according to the first embodiment.Block diagram of the base station device according to the first embodiment.Block diagram of the terminal device according to the first embodiment.A conceptual diagram of the communication method according to the first embodiment.A conceptual diagram showing the sequence in the communication method according to the first embodiment.A conceptual diagram of the communication method according to the first embodiment.A conceptual diagram showing the sequence in the communication method according to the first embodiment.Conceptual diagram of the preamble signal according to the first embodiment.A flowchart illustrating the operation of the base station device according to the first embodiment.A flowchart illustrating the operation of the terminal device according to the first embodiment.A conceptual diagram showing the sequence in the communication method according to the second embodiment.A conceptual diagram showing the sequence in the communication method according to the second embodiment.Conceptual diagram of the RRC connection request signal according to the second embodiment.A flowchart illustrating the operation of the base station device according to the second embodiment.A flowchart illustrating the operation of the terminal device according to the second embodiment.A flowchart illustrating the operation of the base station device according to the third embodiment.A flowchart illustrating the operation of the terminal device according to the third embodiment.A flowchart showing the operation of a terminal device according to a modified example of the third embodiment. The embodiments of the present invention will be described below with reference to the drawings. In the drawings, identical or equivalent elements are denoted by the same reference numerals, and redundant descriptions are omitted. <First Embodiment> This invention will now describe a base station device, terminal device, and communication method according to a first embodiment. This embodiment relates to a base station device, terminal device, and communication method in a 5G network, and concerns a method for switching from broadcast mode to unicast mode when the communication conditions deteriorate while a terminal device is communicating in broadcast mode in an idle state. Figure 1 is a conceptual diagram of the communication system according to this embodiment. As shown in the figure, the communication system 100 includes a core network device 200, a base station device 300, and a terminal device 400. The core network device 200 is a backbone network, for example, a network that controls a mobile network. The core network device 200 is connected to the base station device 300 and can communicate with each other. In this embodiment, the core network device 200 may be a 5th Generation Core network (5GC) compatible with Stand Alone (SA), or an Evolved Packet Core (EPC) compatible with Non-Stand Alone (NSA). The base station device 300 supports NR (New Radio) and is also called gNodeB. The base station device 300 forms a cell 500 and communicates with terminal devices 400 located within the cell 500. The terminal device 400 is located within the cell 500, communicates with the base station device 300 using NR, and is also called UE (User Equipment). The terminal device 400 may be a communication terminal such as a smartphone or a tablet or laptop PC. Furthermore, the terminal device 400 may be an application for eMBB (Enhanced Mobile Broadband), URLLC (Ultra-Reliable & Low Latency Communications), and mMTC (massive Machine Type Communication). eMBB, URLLC, and mMTC are usage scenarios for NR and 5GC as defined, for example, in 3GPP Release 15. Next, the details of the base station device 300 will be explained using Figure 2A. Figure 2A is a block diagram of the base station device 300. The base station device 300 is capable of communicating information with the terminal device 400 via broadcast and unicast, and as shown in Figure 2A, it comprises a transmitting/receiving unit 310, a determination unit 320, a control unit 330, and a storage unit 340. The transmitting/receiving unit 310 transmits and receives signals with the terminal device 400. In this embodiment, the transmitting/receiving