Base station, terminal device, communication method, and communication program

Abstract

A base station of the present disclosure includes a control unit. The control unit transmits, to a terminal device, first information for measuring a communication quality of a downlink communication, the first information including second information on at least one of a first signal waveform and a second signal waveform. The control unit receives, based on the first information, a measurement result of the communication quality performed by the terminal device using a signal having at least one of the first signal waveform and the second signal waveform. The signal having the first signal waveform is a multi-carrier signal, and the signal having the second signal waveform is a single-carrier signal.

Description

Technical Field

[0001] This disclosure relates to base stations, terminal equipment, communication methods, and communication programs. Background Technology

[0002] Within the 3rd Generation Partnership Project (3GPP (registered trademark)), radio access schemes and radio networks for cellular mobile communications (hereinafter also referred to as "Long Term Evolution (LTE)", "LTE-A", "LTE-A Pro", "New Radio (NR)", "New Radio Access Technology (NRAT)", "Evolved Universal Terrestrial Radio Access (EUTRA)" or "Further EUTRA (FEUTRA)") are being studied.

[0003] In the following description, LTE includes LTE-A, LTE-A Pro, and EUTRA, and NR includes NRAT and FEUTRA. In LTE, the base station (base station equipment) is also called an eNodeB (evolved NodeB), and in NR, the base station (base station equipment) is also called a gNodeB. Furthermore, in both LTE and NR, the terminal equipment (mobile station, mobile station equipment, or terminal) is also called user equipment (UE). LTE and NR are cellular communication systems in which multiple areas covered by base stations are arranged in a cellular manner. A single base station can manage multiple cells.

[0004] 5G NR is the next-generation radio access solution relative to LTE, and it is a different radio access technology (RAT) from LTE. NR is an access technology capable of supporting a variety of use cases, including enhanced mobile broadband (eMBB), massive machine-type communications (mMTC), and ultra-reliable low-latency communications (URLLC). NR has been standardized to support the technical framework corresponding to the use cases, requirements, and deployment scenarios in these use cases.

[0005] In recent years, there has been progress in supporting high-frequency bands such as millimeter waves and terahertz waves, or in reducing base station costs. Therefore, it is necessary to reduce the peak-to-average power ratio (PAPR) in downlink communication.

[0006] Reference List

[0007] Patent documents

[0008] PTL 1: WO 2023 / 095708 Summary of the Invention

[0009] Technical issues

[0010] To address the PAPR issue caused by reduced base station costs as described above, it is necessary to consider methods for performing communications more efficiently.

[0011] Therefore, this disclosure provides a mechanism for more efficient communication in a communication system in which base stations and terminal devices communicate with each other.

[0012] The above-described problem or objective is merely one of many problems or objectives that can be solved or achieved by the various embodiments disclosed in this specification.

[0013] Solution to the problem

[0014] The base station disclosed herein includes a control unit. The control unit sends first information to a terminal device for measuring the communication quality of downlink communication, the first information including second information regarding at least one of a first signal waveform and a second signal waveform. Based on the first information, the control unit receives a measurement result of the communication quality performed by the terminal device using a signal having at least one of the first and second signal waveforms. The signal having the first signal waveform is a multi-carrier signal, and the signal having the second signal waveform is a single-carrier signal. Attached Figure Description

[0015] Figure 1 This is a diagram illustrating an example of signal processing for uplink communication in 5G NR.

[0016] Figure 2 This is a diagram showing an overview of radio networks, including non-terrestrial networks.

[0017] Figure 3 This is a diagram illustrating an overview of satellite communications provided by a communication system.

[0018] Figure 4 This is a diagram illustrating an example of a cell composed of non-geostationary satellites.

[0019] Figure 5 This is a sequence diagram illustrating an example of a handover process.

[0020] Figure 6 This is a sequence diagram illustrating another example of the switching process.

[0021] Figure 7 This is a diagram illustrating an example of communication processing according to the proposed technology of this disclosure.

[0022] Figure 8 This is a diagram illustrating an example of the overall configuration of a communication system according to an embodiment of the present disclosure.

[0023] Figure 9 This is a block diagram illustrating an example configuration of a base station according to an embodiment of the present disclosure.

[0024] Figure 10This is a block diagram illustrating an example configuration of a wireless transmitting unit according to an embodiment of the present disclosure.

[0025] Figure 11 This is a block diagram illustrating an example configuration of a first signal waveform transmitting unit according to an embodiment of the present disclosure.

[0026] Figure 12 This is a block diagram illustrating an example configuration of a second signal waveform transmitting unit according to an embodiment of the present disclosure.

[0027] Figure 13 This is a block diagram illustrating an example configuration of a terminal device according to an embodiment of the present disclosure.

[0028] Figure 14 This is a block diagram illustrating an example configuration of a wireless receiving unit according to an embodiment of the present disclosure.

[0029] Figure 15 This is a block diagram illustrating an example configuration of a first signal waveform receiving unit according to an embodiment of the present disclosure.

[0030] Figure 16 This is a block diagram illustrating an example configuration of a second signal waveform receiving unit according to an embodiment of the present disclosure.

[0031] Figure 17 This is a sequence diagram illustrating an example of the switching process according to an embodiment of the present disclosure.

[0032] Figure 18 This is a sequence diagram illustrating an example of a conditional switching process according to an embodiment of the present disclosure.

[0033] Figure 19 This is a block diagram illustrating an example of a hardware configuration of a computer according to this disclosure. Detailed Implementation

[0034] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In this specification and the drawings, components having substantially the same functional configuration are indicated by the same reference numerals, and repeated descriptions thereof are omitted.

[0035] Furthermore, in this specification and accompanying drawings, components with similar configurations in the embodiments can be distinguished by appending at least one of different letters and numbers after the same reference numerals. However, when it is not necessary to specifically distinguish similar components, only the same reference numerals are assigned. For example, multiple configurations having substantially the same functional configuration may be distinguished as terminal device 50A and terminal device 50B as needed. For example, when it is not necessary to specifically distinguish terminal device 50A and terminal device 50B, terminal device 50A and terminal device 50B may be simply referred to as terminal device 50.

[0036] The one or more embodiments (including examples, variations, and application examples) described below can be implemented independently. On the other hand, the various embodiments described below can be implemented by suitably combining at least a portion of one embodiment with at least a portion of another embodiment. The various embodiments may include different novel features. Therefore, the various embodiments can help achieve or solve different purposes or problems and can achieve different effects.

[0037] <<1. Introduction>>

[0038] <1-1. Background>

[0039] <1-1-1. DFT-S-OFDM Transmission>

[0040] First, in the uplink communication of 5G NR, Orthogonal Frequency Division Multiplexing (OFDM) transmission and Discrete Fourier Transform Extended Orthogonal Frequency Division Multiplexing (DFT-S-OFDM) transmission are used.

[0041] Figure 1 This is a diagram illustrating an example of signal processing for uplink communication in 5G NR.

[0042] like Figure 1 As shown, parity bits for error correction are added to the transmitted signal sequence through error-correcting coding (channel coding). Subsequently, a number of bits corresponding to the transmission resources or modulation scheme are extracted from the transmitted signal sequence through rate matching. Interleaving and scrambling are then applied to the extracted bits.

[0043] Subsequently, the bit sequence is mapped to complex signal points through modulation processing. When transmission is performed in multiple layers, the bit sequence is mapped to complex signal points in each layer.

[0044] Here, in DFT-S-OFDM transmission, such as Figure 1 As shown, a Discrete Fourier Transform (DFT) process called transform precoding is performed. This process, specifically the DFT process performed here, can be referred to by a different name than transform precoding. Furthermore, this transform precoding process is omitted in OFDM transmission.

[0045] Subsequently, weights are sent via precoding, resource mapping is performed, and then the transmitted signal in the frequency domain is converted into a transmitted signal (time-axis signal) in the time domain via OFDM processing and transmitted. Because... Figure 1 The processing is uplink communication, so the transmission signal in the time domain is sent from the terminal device to the base station.

[0046] On the receiving side, firstly, the received signal in the time domain is converted into a signal in the frequency domain (frequency axis signal) through OFDM processing. Then, after resource demapping, frequency equalization processing (equalizer) is performed to compensate for distortion caused by radio wave propagation.

[0047] Here, in DFT-S-OFDM transmission, such as Figure 1 As shown, an inverse discrete Fourier transform (IDFT) process called de-precoding is performed. This de-precoding process is omitted in OFDM transmission.

[0048] Subsequently, the signals mapped to multiple layers are recovered, and soft decision is performed on each bit from the complex signal points. For the bit values ​​obtained through this soft decision, descrambling, deinterleaving, rate matching removal, and error correction decoding (channel decoding) are performed to obtain the received signal sequence.

[0049] As mentioned above, traditionally, single-carrier schemes (such as DFT-S-OFDM transmission in the example above) have been introduced in uplink communication to reduce PAPR.

[0050] Here, as mentioned above, in recent years, due to support for high-frequency bands such as millimeter waves and terahertz waves or the reduction in base station costs, there is also a need to reduce PAPR in downlink communication.

[0051] Considering the reduced cost and expanded coverage of such base stations, it is conceivable that a single-carrier scheme with low PAPR could also be introduced into downlink communication.

[0052] <1-1-2. Satellite Communications>

[0053] One type of communication requiring reduced PAPR is satellite communication. One type of mobile satellite used for satellite communication is a small satellite, also known as a cube-sats or microsatellite. Small satellites are inferior to satellites of related technologies in terms of power or antenna gain. Therefore, problems with small satellites can include PAPR issues due to the lack of a high-performance power amplifier.

[0054] Therefore, the introduction of single-carrier schemes with low PAPR is being considered in satellite communications.

[0055] This section provides an overview of satellite communications. For example, in cellular mobile communications, ground-based base stations (e.g., eNodeBs (eNBs), gNodeBs (gNBs), RAN nodes (including EUTRAN and NGRAN)) or relay equipment constitute cells (e.g., macrocells, microcells, femtocells, or small cells) and provide a radio network. Ground-based base stations or relay equipment are also called ground stations.

[0056] The radio network provided by this ground station is called the terrestrial network.

[0057] On the other hand, with the increasing need to reduce base station costs and provide coverage to areas where radio waves from base stations are difficult to reach, the provision of radio networks to terminal devices via base stations / relay stations other than ground stations (such as satellite stations or aircraft stations) is being considered. Base stations / relay stations other than ground stations are called non-ground stations (or non-ground base stations / non-ground relay stations).

[0058] In addition, radio networks provided from non-terrestrial stations are called non-terrestrial networks (NTN).

[0059] Examples of communication equipment other than ground stations include satellite stations and aircraft stations. Satellite stations are devices with radio communication capabilities that float outside the atmosphere, such as artificial satellites. Satellite stations here include low Earth orbit (LEO) satellites, medium Earth orbit (MEO) satellites, geostationary Earth orbit (GEO) satellites, and highly elliptical orbit (HEO) satellites.

[0060] Aircraft stations are devices with radio communication capabilities that float within the atmosphere, such as airplanes or balloons. Aircraft stations here include unmanned aerial systems (UAS), tethered UAS, lighter-than-air UAS (LTA), heavier-than-air UAS (HTA), and high-altitude UAS platforms (HAPs).

[0061] From the perspective of 3GPP (registered trademark) cellular mobile communications, communication equipment other than ground stations can also be called base stations (e.g., eNodeB (eNB), gNodeB (gNB), RAN nodes (including EUTRAN and NGRAN)).

[0062] Figure 2 This is a diagram illustrating an overview of radio networks, including non-terrestrial networks. Figure 2 The image shows an example of a radio network provided by communication system 1. Figure 2 The communication system 1 includes management equipment 101, ground stations 201 to 205, non-ground stations 301 to 305, relay stations 401 and 402, and terminal equipment 501 and 502.

[0063] Communication system 1 provides users with a radio network enabling mobile communication through the coordinated operation of various radio communication devices constituting communication system 1. In this embodiment, the radio network includes, for example, a radio access network and a core network. The radio communication devices here are devices with radio communication functions, and correspond to... Figure 2 The example includes ground station 20, non-ground station 30, relay station 40, and terminal equipment 50.

[0064] Management device 10 is, for example, a device constituting the core network CN. Management device 10 is connected to network PN. Management device 10 is connected to ground station 20 and non-ground station 30, and enables terminal device 50 to connect to network PN. Network PN is a public data network such as the Internet. Network PN is not limited to the Internet, and can be, for example, a local area network (LAN), a wide area network (WAN), a telephone network (mobile phone network, fixed-line telephone network, etc.), or a local Internet Protocol (IP) network. Of course, network PN can be another mobile network. For example, network PN can be a cellular network provided by an entity different from the entity operating communication system 1 (e.g., a commercial entity such as a mobile network operator (MNO)).

[0065] Ground station 20 and non-ground station 30 are base stations or relay stations. In the following description, ground station 20 and non-ground station 30 are base stations, but ground station 20 and non-ground station 30 can be relay stations. Ground station 20 is, for example, a terrestrial base station in a structure installed on the ground, and non-ground station 30 is, for example, a non-terrestrial base station such as a satellite station or a High Altitude Platform Station (HAPS). Ground station 20 and non-ground station 30 each constitute a cell. A cell is an area covering radio communication. A cell can be any of a macro cell, micro cell, femtocell, and small cell. Note that communication system 1 can be configured such that a single base station (satellite station) manages multiple cells, or it can be configured such that multiple base stations manage one cell.

[0066] exist Figure 2 In the example, ground stations 201 and 202 constitute terrestrial network TN1, and ground stations 203, 204, and 205 constitute terrestrial network TN2. Terrestrial networks TN1 and TN2 are, for example, networks operated by radio communication operators such as telephone companies.

[0067] Terrestrial networks TN1 and TN2 can be operated by different radio operators, or they can be operated by the same radio operator. Terrestrial networks TN1 and TN2 can be considered as a single terrestrial network.

[0068] Terrestrial networks TN1 and TN2 are each connected to the core network. Figure 2 In the example, ground station 20, which constitutes the terrestrial network TN2, is connected to the core network CN1, for example, which is composed of management equipment 101.

[0069] When the radio access scheme of terrestrial network TN2 is LTE, the core network CN1 is EPC. Furthermore, when the radio access scheme of terrestrial network TN2 is NR, the core network CN1 is 5GC. Of course, the core network CN1 is not limited to EPC or 5GC, and can be the core network for another radio access scheme.

[0070] exist Figure 2 In the example, terrestrial network TN1 is not connected to the core network, but terrestrial network TN1 can be connected to core network CN1. Furthermore, terrestrial network TN1 can be connected to a different core network than core network CN1 (not shown).

[0071] The core network CN1 includes, for example, gateway devices and gateway switches, and is connected to network PN1 via the gateway devices or gateway switches. As mentioned above, network PN1 is a public network such as the Internet.

[0072] A gateway device can be a server device connected to the Internet, a local IP network, etc. A gateway switch is, for example, a switch connected to a telephone company's telephone network. Management device 101 can function as a gateway device or a gateway switch.

[0073] Figure 2 The non-terrestrial station 30 shown is, for example, a satellite station or an aircraft station. A group (or satellite station) constituting a non-terrestrial network is called a space-borne platform. A group (or aircraft station) constituting a non-terrestrial network is called an airborne platform.

[0074] exist Figure 2 In the example, non-ground stations 301, 302, and 303 constitute space-based platform SBP1, and non-ground station 304 constitutes space-based platform SBP2. Non-ground station 305 constitutes airborne platform ABP1.

[0075] Non-ground station 30 can communicate with the ground network or core network via relay station 40. Of course, non-ground station 30 can also communicate directly with the ground network or core network without intervening in relay station 40.

[0076] Non-ground station 30 can communicate with terminal device 50 via relay station 40, or can communicate directly with terminal device 50. Non-ground stations 30 can communicate directly with each other without intervening in relay station 40.

[0077] Relay station 40 relays communication between ground equipment and non-ground station 30. A relay station is also called an earth station (VMS, gateway, control earth station, or hub). Relay station 40 can be a ground station or a non-ground station. Figure 2 In the example, relay station 402 relays communication between ground station 20 and non-ground station 30, and relay station 401 relays communication between relay management device 10 and non-ground station 30.

[0078] Relay station 40 can relay communication between terminal equipment 50 and non-ground station 30. Relay station 40 can also communicate with another relay station 40.

[0079] Terminal device 50 is capable of communicating with both ground stations and non-ground stations. Figure 2 In the example, terminal device 501 is capable of communicating with ground stations constituting TN1. Furthermore, terminal device 501 is capable of communicating with non-ground stations constituting space-based platforms SBP1 and SBP2.

[0080] In addition, terminal device 50 can also communicate with non-ground stations constituting the airborne platform ABP1. Note that terminal device 50 can communicate with relay station 40. Terminal device 50 can communicate directly with another terminal device 50. Terminal device 501 can communicate directly with terminal device 502.

[0081] Examples of terminal devices 50 (earth terminal devices) corresponding to non-terrestrial networks include mobile phones, smartphones, cars, buses, trains, airplanes, machine-to-machine (M2M) / Internet of Things (IoT) devices, relay stations for relaying satellite communications, and base stations for receiving satellite communications.

[0082] The equipment and terminal equipment 50 that constitute the space-based platforms SBP1 and SBP2 perform satellite communication. Satellite communication is radio communication between the satellite station and the communication equipment.

[0083] Figure 3 This diagram illustrates an overview of satellite communications provided by communication system 1. Satellite stations are mainly divided into geostationary satellite stations and low-Earth orbit satellite stations.

[0084] A geostationary satellite station is a satellite station located in a geostationary orbit and revolving around the Earth at the same speed as the Earth's rotation. Figure 3 In the example, non-ground station 304, which constitutes the space-based platform SBP2, is a geostationary satellite station. A geostationary orbit is an orbit at an altitude of approximately 35,786 km within a satellite orbit.

[0085] Geostationary orbit is also called geostationary Earth orbit (GEO). The speed of a geostationary satellite station relative to the ground-based terminal equipment 50 is essentially zero, and it appears stationary from the perspective of the ground-based terminal equipment 50. The non-ground station 304 performs satellite communication with the terminal equipment 501, 503, 504, etc., located on Earth.

[0086] A low Earth orbit (LEO) satellite station is a satellite station that orbits in low Earth orbit. Figure 3In the example, the non-ground stations 301 and 302 that constitute the space-based platform SBP1 are low Earth orbit (LEO) satellite stations. LEO is a satellite orbit with an altitude of approximately 2000 km or less. LEO is also known as low Earth orbit (LEO).

[0087] Unlike geostationary satellite stations, low-Earth orbit satellite stations have a relative velocity with respect to ground terminal equipment 50 and appear to be moving when viewed from ground terminal equipment 50. Non-ground stations 301 and 302 each constitute a cell and perform satellite communication with terminal equipment 501, 503, 504, etc., located on Earth.

[0088] exist Figure 3 In the diagram, only two non-ground stations, 301 and 302, are shown as satellite stations constituting the space-based platform SBP1. However, in reality, a satellite constellation is formed by many satellite stations. In this case, the number of satellite stations constituting the space-based platform SBP1 is more than three (e.g., tens to thousands).

[0089] exist Figure 3 In the example, only geostationary satellite stations and low Earth orbit (LEO) satellite stations are shown as satellite stations, but the satellite stations constituting communication system 1 may include medium Earth orbit (MEO) satellite stations. A MEO satellite station is a satellite station orbiting in a medium Earth orbit. MEO is an orbit located between LEO and geostationary orbit. MEO is also known as medium Earth orbit (MEO).

[0090] Additionally, the satellite stations constituting communication system 1 may include satellite stations in highly elliptical orbits (HEO). Note that the satellite stations forming a satellite constellation may include not only low Earth orbit satellite stations, but also medium Earth orbit satellite stations, highly elliptical orbit satellite stations, and geostationary satellite stations.

[0091] Figure 4 This is a diagram illustrating an example of a cell composed of non-geostationary satellites. Figure 4 The image shows cell C formed by non-ground station 302. Figure 4 In the example, non-ground station 302 is a low-Earth orbit satellite station. The satellite station orbiting in low Earth orbit communicates with ground terminal equipment 50 with a predetermined orientation toward the ground.

[0092] For example, in Figure 4 In the example shown, the angle R is 40°. Figure 4 In the example, the radius D of the cell C formed by the non-ground station 302 is, for example, 1000 km. The low Earth orbit satellite station moves at a constant speed. In cases where the low Earth orbit satellite station has difficulty providing satellite communication to the terminal equipment 50 on the ground, subsequent low Earth orbit satellite stations (adjacent satellite stations) provide satellite communication.

[0093] exist Figure 4 In the example scenario, when non-ground station 302 has difficulty providing satellite communication to ground terminal equipment 50, subsequent non-ground station 303 provides satellite communication. The values ​​of angle R and radius D mentioned above are merely examples and are not limited thereto.

[0094] Medium Earth orbit (MEO) and low Earth orbit (LEO) satellites move in the sky at very high speeds in their orbits. For example, a LEO satellite at an altitude of 600 km moves in its orbit at a speed of 7.6 km / s.

[0095] Low-Earth orbit satellites form cells (or beams) with radii ranging from tens to hundreds of kilometers on the ground. However, because these cells move with the satellites, handover may be necessary even if the ground terminal equipment remains stationary. For example, assuming a cell with a diameter of 50 km and the ground terminal equipment remains stationary, a handover may occur in approximately 6 to 7 seconds.

[0096] As described above, terminal device 50 is capable of radio communication using a non-terrestrial network. The non-terrestrial station 30 of communication system 1 constitutes a non-terrestrial network. Therefore, communication system 1 can extend its service to terminal device 50 located in areas not covered by terrestrial networks.

[0097] For example, communication system 1 can provide services to terminal devices 50 in areas not covered by terrestrial networks (e.g., outside the coverage area of ​​the cell provided by ground station 20). Communication system 1 can provide public safety communications and critical communications to communication devices such as Internet of Things (IoT) devices and machine-type communication (MTC) devices.

[0098] Furthermore, by using non-terrestrial networks, service reliability or recoverability is improved. This enables communication system 1 to reduce the vulnerability of the service to physical attacks or natural disasters.

[0099] Furthermore, communication system 1 can achieve service connections with aircraft terminal devices such as airplane passengers and drones, as well as with mobile terminal devices such as ships and trains. Additionally, communication system 1 can provide A / V content, group communication, IoT broadcast services, software download services, efficient multicast services such as emergency messages, and efficient broadcast services. Moreover, communication system 1 can also offload services between terrestrial and non-terrestrial networks.

[0100] Here, satellite communication has been described as an example of introducing a single-carrier scheme into downlink communication in radio communication; however, radio communication incorporating a single-carrier scheme is not limited to satellite communication. That is, the technology according to this embodiment is not limited to application in non-terrestrial networks, but also applicable to terrestrial networks.

[0101] To simplify the description, the technology according to this embodiment will be described below using downlink communication in a terrestrial network as an example. However, the technology according to this embodiment can also be applied to downlink communication in non-terrestrial networks.

[0102] <1-1-3. Switch>

[0103] As described above, when a single-carrier scheme is introduced into downlink communication, multi-carrier schemes (e.g., the OFDM transmission described above) and single-carrier schemes (e.g., the DFT-S-OFDM transmission described above) coexist.

[0104] Here, the terminal device 50 performs a measurement of the communication quality for downlink communication and reports the measurement results (measurement report) to the base station 20. The communication quality measurement results are used for communication with the base station 20 (e.g., downlink communication), handover determination, etc.

[0105] The following will describe the switching process of related technologies as an example of using communication quality processing.

[0106] Figure 5 This is a sequence diagram illustrating an example of the switching process. Figure 5 This illustrates a scenario where terminal device 50 switches from a serving cell of a serving (source) base station that is the source of the handover to a target cell of a target base station that is the destination of the handover.

[0107] like Figure 5 As shown, terminal device 50 performs measurement (measurement control) and sends a measurement report to the serving base station (step S101). Similarly, terminal device 50 performs measurement and sends a measurement report to the target base station (step S102).

[0108] The serving base station determines whether handover of terminal device 50 is required based on the measurement report (step S103). When the serving base station determines that handover is required, the serving base station requests the target base station to perform handover (step S104).

[0109] When the target base station receives a handover request, the target base station performs admission control (step S105) and notifies the serving base station of the confirmation of the handover request (step S106).

[0110] Subsequently, the serving base station sends an RRC reconfiguration including a handover command to the terminal device 50 (step S107) and notifies the handover to proceed.

[0111] When terminal device 50 receives RRC reconfiguration, terminal device 50 separates from the serving cell of the serving base station (step S108) and performs an initial access procedure with the target base station. For example, terminal device 50 sends a Physical Random Access Channel (PRACH) to the target base station (step S109).

[0112] The target base station sends a random access response to the terminal device 50 (step S110). The terminal device 50 sends a random access response to the target base station (step S111), thereby completing the initial access process and handover process.

[0113] This illustration shows the terminal device 50 performing a 2-step random access procedure (2-step RACH) as the initial access procedure, but this disclosure is not limited thereto. The terminal device 50 may also perform a 4-step random access procedure (4-step RACH) as the initial access procedure.

[0114] Therefore, in Figure 5 In the handover shown, terminal device 50 begins the handover the moment it receives the handover command from the serving base station.

[0115] Alternatively, as another example of handover, there exists a conditional handover in which the serving base station informs the terminal device 50 in advance about information regarding the handover destination candidates.

[0116] Figure 6 This is a sequence diagram illustrating another example of the switching process. Figure 6 The illustration shows a scenario where terminal device 50 selects one of a first target base station and a second target base station as candidates for handover destination and performs a handover. The first target base station has target candidate cell #1, and the second target base station has target candidate cell #2.

[0117] like Figure 6 As shown, the terminal device 50 performs the measurement and sends a measurement report to the serving base station (step S201).

[0118] The serving base station determines whether a conditional handover of terminal device 50 is required based on the measurement report (step S202). When it is determined that a conditional handover is required, the serving base station requests the first target base station to perform the handover (step S203) and requests the second target base station to perform the handover (step S204).

[0119] When the first target base station receives a handover request, it performs admission control (step S205). Similarly, when the second target base station receives a handover request, it performs admission control (step S206). The first target base station notifies the serving base station of the confirmation of the handover request (step S207). The second target base station notifies the serving base station of the confirmation of the handover request (step S208).

[0120] Subsequently, the serving base station sends an RRC reconfiguration to the terminal device 50 (step S209). The RRC reconfiguration includes, for example, information about the first and second target base stations that are candidates for handover destination, as well as information about the execution trigger used to perform conditional handover.

[0121] When terminal device 50 receives an RRC reconfiguration, it sends an RRC reconfiguration completion message to the serving base station (step S210) and evaluates the execution trigger for performing conditional handover (step S211). When terminal device 50 evaluates and detects the execution trigger (step S212), it separates from the serving cell (serving base station) (step S213) and begins the initial connection process with the base station as the handover destination. Figure 6 In this case, it is assumed that the first target base station is detected as the base station to be used for handover.

[0122] like Figure 6 As shown, terminal device 50 performs an initial connection procedure with the first target base station. The initial connection procedure is similar to... Figure 5 The process shown is the same.

[0123] The first target base station, having completed the initial connection process and connected to the terminal device 50, notifies the serving base station that the handover has been successful (step S214). Upon receiving the successful handover notification, the serving base station notifies the second target base station, which was not selected as the handover destination, that the handover has been cancelled (step S215), thereby cancelling the handover to the second target base station.

[0124] Therefore, in conditional handover, the serving base station does not determine the target base station as the handover destination, but instead notifies the terminal device 50 of candidate target base stations. Thus, the terminal device 50 can select a connectable target base station and perform the handover at the appropriate time.

[0125] Furthermore, in conditional handover, to achieve seamless handover, terminal devices 50, for example, Figure 6 In step S212, the conditional handover execution trigger is detected, and then in the next step S213, the device detaches from the serving base station. In other words, to avoid periods where communication with both the serving base station and the target base station candidate is impossible, and periods where initial connection cannot be performed, the terminal device 50, for example, in… Figure 6 In step S212, the execution trigger of conditional handover is detected, and then the device is separated from the serving base station in the next step S213.

[0126] Therefore, the terminal device 50 and / or the serving base station will use the measurement (communication quality measurement) results to determine the handover execution.

[0127] <1-2. Questions>

[0128] As described above, when a single-carrier scheme is introduced into the downlink communication of communication system 1, a multi-carrier scheme (e.g., the OFDM transmission described above) and a single-carrier scheme (e.g., the DFT-S-OFDM transmission described above) coexist.

[0129] In addition, as described above, in order to make decisions such as switching, the terminal device 50 performs the measurement of the reference signal and reports the measurement results (measurement report).

[0130] In a communication system in which both multi-carrier and single-carrier schemes are implemented, a mechanism is needed for terminal device 50 to perform measurements and measurement reports.

[0131] <1-3. Proposed Technology>

[0132] Figure 7 This is a diagram illustrating an example of communication processing according to the proposed technology of this disclosure. The communication processing according to the proposed technology is performed between base stations 201 and 202 of the communication system SYS1 and terminal device 50.

[0133] Base station 201 is the serving base station for the providing cell. Base station 202 is the target base station for the providing cell's neighboring cells or target cells. For example, when performing the conditional handover described above, base station 202 is the target base station for the providing cell's neighboring cells. When performing a regular handover that is not a conditional handover described above, base station 202 is the target base station for the target cell.

[0134] like Figure 7 As shown, base station 201 obtains waveform information from base station 202 regarding signal waveforms that can be used for downlink communication in neighboring cells or a target cell (step S11). The waveform information includes, for example, information about at least one of a first signal waveform and a second signal waveform. The first signal waveform is, for example, a multi-carrier signal waveform, and the second signal waveform is, for example, a single-carrier signal waveform.

[0135] Base station 201 sends measurement information (example of first information) to terminal device 50 for measuring the communication quality of downlink communication (step S12). The measurement information may include, for example, waveform information obtained by base station 201 from base station 202. That is, the measurement information includes, for example, information about at least one of a first signal waveform and a second signal waveform (example of second information).

[0136] Base station 202 transmits a signal (reference signal) for measuring the communication quality of downlink communication (step S13). Base station 202, for example, transmits a reference signal having a first signal waveform. Figure 7 (dashed line in the middle) and a reference signal with a second signal waveform ( Figure 7 (single-dot dashed line in the text).

[0137] exist Figure 7 In this process, base station 202 transmits both a reference signal having a first signal waveform and a reference signal having a second signal waveform, but base station 202 may transmit only one of the reference signal having the first signal waveform and the reference signal having the second signal waveform.

[0138] Terminal device 50 measures the communication quality of downlink communication based on reference signals and reports the measurement results to base station 201 (step S14).

[0139] For example, terminal device 50 receives a reference signal having a first signal waveform from resources based on measurement information and measures a first communication quality. Furthermore, for example, terminal device 50 receives a reference signal having a second signal waveform from resources based on measurement information and measures a second communication quality. Terminal device 50 reports the measurement information regarding the first and second communication qualities to base station 201.

[0140] Base station 201 determines the execution of handover of terminal device 50 based on measurement information and notifies terminal device 50 of instruction information (e.g., handover command) for instructing handover (step S15).

[0141] The terminal device 50, which has received the instruction information, performs a handover from base station 201 to base station 202 (step S16).

[0142] As described above, in the communication system according to the present disclosure, base station 201 notifies terminal device 50 of measurement information (corresponding to first information) for measurement (measurement of communication quality of downlink communication). The measurement information includes information about at least one of a first signal waveform and a second signal waveform.

[0143] Therefore, the terminal device 50 receives measurement information, thereby receiving at least one of a reference signal having a first signal waveform and a reference signal having a second signal waveform, and performs a measurement.

[0144] Base station 201 can receive measurement result reports (measurement reports) from terminal device 50. Base station 201 can perform operations based on the measurement reports (e.g., downlink communication and handover determination).

[0145] In the following embodiments, base station 20 can be implemented by, for example, a non-terrestrial base station 30 operating as a communication device, such as a terrestrial base station, satellite station, drone, balloon, or aircraft.

[0146] Furthermore, in the following embodiments, when specific examples are shown, there are parts that are described by indicating specific values, but the values ​​are not limited to these examples and other values ​​may also be used.

[0147] In addition, the resources in this embodiment represent frequency, time, resource elements (including REG, CCE and CORESET), resource blocks, bandwidth portions, component carriers, symbols, sub-symbols, time slots, mini time slots, non-time slots, sub-time slots, subframes, frames, PRACH timing, timing, codes, multiple access physical resources, multiple access signatures, subcarrier spacing (parameter set), etc.

[0148] Furthermore, in the following embodiments, CP-OFDM is used as an example of a multi-carrier scheme (first signal waveform), and DFT-S-OFDM is used as an example of a single-carrier scheme (second signal waveform). The CP-OFDM and DFT-S-OFDM described above are merely examples, and the multi-carrier and single-carrier schemes are not limited thereto.

[0149] As described above, in the case of a single-carrier scheme (second signal waveform), transform precoding is applied in the transmission signal processing, while in the case of a multi-carrier scheme (first signal waveform), transform precoding is not applied (see...). Figure 1 ).

[0150] Therefore, the processing associated with the single-carrier scheme (DFT-S-OFDM) is interpreted as applying transform precoding. Furthermore, the processing associated with the multi-carrier scheme (CP-OFDM) is interpreted as not applying transform precoding.

[0151] Furthermore, in the following embodiments, the switching command (the above instruction information) can be interpreted as RRC reconfiguration, etc.

[0152] <<2. Configuration Example of Communication System>>

[0153] <2-1. Example of Overall Configuration of Communication System>

[0154] Figure 8 This is a diagram illustrating an example of the overall configuration of a communication system SYS1 according to an embodiment of the present disclosure. Figure 8 As shown, the communication system SYS1 according to this embodiment includes a base station 20 and multiple terminal devices 50A and 50B.

[0155] The communication system SYS1 may include management device 10, non-ground station 30, and relay station 40 (see...). Figure 2 )wait.

[0156] (Base station 20)

[0157] Base station 20 is a communication device that operates cell C1 and provides radio communication services to one or more terminal devices 50 located within the coverage area of ​​cell C1. Cell C1 operates according to any radio communication scheme such as LTE or NR. Base station 20 is connected to a core network. The core network is connected to a packet data network (not shown) via a gateway device (not shown). Furthermore, base station 20 operates a beam that can be identified by a synchronization signal / PBCH block (SSB) and can transmit and receive data with one or more terminal devices 50 via one or more beams.

[0158] Base station 20 may be composed of a collection of multiple physical or logical devices. For example, in this embodiment, base station 20 may be distinguished as multiple devices of baseband unit (BBU) and RU, and is interpreted as a collection of multiple devices. Alternatively, in this embodiment, base station 20 may be any one or both of BBU and RU. BBU and RU may be connected via a predetermined interface (e.g., eCPRI). Alternatively, RU may be referred to as remote radio unit (RRU) or radio point (RD). Alternatively, RU may correspond to gNB-DU as described later. Alternatively, BBU may correspond to gNB-CU as described later. Alternatively, RU may be connected to gNB-DU as described later. Furthermore, BBU may correspond to a combination of gNB-CU and gNB-DU as described later. Alternatively, RU may be a device integrated with an antenna. The antenna included in base station 20 (e.g., an antenna integrated with an RU) may employ an advanced antenna system and may support MIMO (e.g., FD-MIMO) or beamforming. In an advanced antenna system, the antennas included in the base station 20 (e.g., antennas integrated with the RU) may include, for example, 64 transmit antenna ports and 64 receive antenna ports.

[0159] Furthermore, multiple base stations 20 can be interconnected. One or more base stations 20 may be included in a radio access network (RAN). That is, base station 20 may be simply referred to as RAN, RAN node, access network (AN), or AN node. The RAN in LTE is called Enhanced Universal Terrestrial RAN (EUTRAN). The RAN in NR is called NGRAN. The RAN in W-CDMA (UMTS) is called UTRAN. Base station 20 in LTE is called Evolved Node B (eNodeB) or eNB. That is, EUTRAN includes one or more eNodeBs (eNBs). Furthermore, base station 20 in NR is called gNodeB or gNB. That is, NGRAN includes one or more gNBs. In addition, EUTRAN may include gNBs (en-gNBs) connected to the core network (EPC) in an LTE communication system (EPS). Similarly, NGRAN may include ng-eNBs connected to the core network 5GC in a 5G communication system (5GS). In addition, or alternatively, when base station 20 is an eNB, gNB, etc., base station 20 may be referred to as 3GPP access. Alternatively, when base station 20 is a radio access point (access point) (e.g., a WiFi (registered trademark) access point), base station 20 may be referred to as a non-3GPP access point. Alternatively, base station 20 may be an optical extension device referred to as a Remote Radio Head (RRH). Alternatively, when base station 20 is a gNB, base station 20 may be referred to as a combination or either of the aforementioned gNB Central Unit (CU) and gNB Distributed Unit (DU). The gNB CU hosts multiple upper-layer access layers (e.g., RRC, SDAP, and PDCP) used for communication with the UE. On the other hand, the gNB-DU hosts multiple lower-layer access layers (e.g., RLC, MAC, and PHY). That is, RRC signaling in messages and information described later (e.g., various SIBs including MIB and SIB1, RRCSetup messages, and RRCReconfiguration messages) can be generated in the gNB CU, while DCI or various physical channels (e.g., PDCCH and PBCH) described later can be generated in the gNB-DU. Alternatively, for example, some configurations (configuration information) such as IE:cellGroupConfig in RRC signaling can be generated in gNB-DU, and the remaining configurations can be generated in gNB-CU. These configurations (configuration information) can be sent and received via the F1 interface, described later. Base station 20 can be configured to communicate with another base station 20. For example, when multiple base stations 20 are a combination of eNBs or a combination of eNBs and en-gNBs, base stations 20 can be connected via the X2 interface. Furthermore, or alternatively, when multiple base stations 20 are a combination of gNBs or a combination of gn-eNBs and gNBs, these devices can be connected via the Xn interface.Alternatively, when multiple base stations 20 are combinations of gNB CUs and gNB DUs, these devices can be connected via the aforementioned F1 interface. Messages and information (RRC signaling or DCI information, and physical channels) described later can be communicated between the multiple base stations 20 (e.g., via the X2, Xn, and F1 interfaces).

[0160] Furthermore, as described above, base station 20 can be configured to manage multiple cells C1. The cells C1 provided by base station 20 are called serving cells. Serving cells include primary cells (PCells) and secondary cells (SCells). When providing dual connectivity to a UE (e.g., terminal device 50) (e.g., EUTRA-EUTRA dual connectivity, EUTRA-NR dual connectivity (ENDC), EUTRA-NR dual connectivity with 5GC, NR-EUTRA dual connectivity (NEDC), or NR-NR dual connectivity), the PCell and zero or more SCells provided by the primary node (MN) are called the primary cell group. Additionally, the serving cell can include primary and secondary cells or primary SCG cells (PSCells). That is, when providing dual connectivity to a UE, the PSCell and zero or more SCells provided by the secondary node (SN) are called the secondary cell group (SCG). Unless specifically configured (e.g., PUCCH on SCells), the Physical Uplink Control Channel (PUCCH) is transmitted in the PCell and PSCell, but not in the SCell. Furthermore, radio link failures are detected in the PCell and PSCell, but not in the SCell (which may not be detected). Therefore, because the PCell and PSCell have special roles in the serving cell, they are each also referred to as special cells (SpCell). A downlink component carrier and an uplink component carrier can be associated with a cell C1. Furthermore, the system bandwidth corresponding to a cell C1 can be divided into multiple bandwidth portions. In this case, one or more bandwidth portions (BWPs) can be configured in the UE, and one bandwidth portion can be used as an active BWP in the UE. Additionally, the radio resources available to the terminal device 50 (e.g., frequency bands, parameter sets (subcarrier spacing), or time slot formats (time slot configuration)) can differ for each cell C1, each component carrier, or each BWP.

[0161] Base station 20 determines the signal waveform to be used for downlink communication with terminal device 50 from multiple signal waveforms, including a single-carrier signal. For example, base station 20 determines to use one of a single-carrier signal and a multi-carrier signal for downlink communication.

[0162] Base station 20, for example, determines the signal waveform to be used for each terminal device 50 and notifies the terminal device 50 of information about the determined signal waveform. Base station 20 performs downlink communication with terminal device 50 using the notified signal waveform.

[0163] exist Figure 8 In the example, base station 20 selects a multi-carrier signal for terminal device 50A located closer to the center of cell C1 and performs downlink communication S1. Additionally, base station 20 selects a single-carrier signal for terminal device 50B located closer to the edge of cell C1 and performs downlink communication S2.

[0164] To perform downlink communication for terminal device 50B, which is located closer to the cell edge, higher transmit power and lower PAPR are required. On the other hand, for terminal device 50A, which is located closer to the center of cell C1, the required transmit power is less than that at the cell edge, so even with a higher PAPR, it is easier to ensure the required transmit power.

[0165] Therefore, base station 20 selects a multi-carrier signal for terminal device 50A located closer to the center of cell C1, and selects a single-carrier signal for terminal device 50B located closer to the edge of cell C1.

[0166] Therefore, base station 20 allocates single-carrier signals to downlink communications that strictly require low PAPR, and allocates signal waveforms other than single-carrier signals (here, multi-carrier signals) to downlink communications with less stringent low PAPR requirements. Thus, base station 20 achieves low PAPR and improved overall system efficiency.

[0167] Here, the situation where base station 20 determines the signal waveform based on the position of terminal device 50 in cell C1 has been described, but the method of determining the signal waveform in base station 20 is not limited to this.

[0168] <2-2. Base Station Configuration Example>

[0169] Figure 9 This is a block diagram illustrating an example configuration of a base station 20 according to an embodiment of the present disclosure. Figure 9 As shown, the base station 20 includes an upper-level processing unit 101, a control unit 103, a receiving unit 105, a transmitting unit 107, and a transceiver antenna 109.

[0170] Base station 20 may support one or more radio access technologies (RATs). For example, base station 20 may support both LTE and NR. In this case, some or all of the units included in base station 20 may be configured according to the RATs. For example, receiving unit 105 and transmitting unit 107 may be configured for LTE and NR respectively.

[0171] In addition, in NR cells, Figure 9 Some or all of the units included in the base station 20 shown can be configured separately according to a set of parameters related to the transmitted signal. For example, in a certain NR cell, the radio receiving unit 1057 and the radio transmitting unit 1077 can be configured separately according to a set of parameters related to the transmitted signal.

[0172] (Upper-level processing unit)

[0173] The upper-layer processing unit 101 outputs downlink data (transmission blocks) to the control unit 103. The upper-layer processing unit 101 performs processing at the Media Access Control (MAC) layer, Packet Data Convergence Protocol (PDCP) layer, Radio Link Control (RLC) layer, and Radio Resource Control (RRC) layer. Furthermore, the upper-layer processing unit 101 generates control information for controlling the receiving unit 105 and the transmitting unit 107, and outputs the control information to the control unit 103.

[0174] The upper-level processing unit 101 performs processing and management related to RAT control, radio resource control, subframe configuration, scheduling control, and / or CSI reporting control. The processing and management in the upper-level processing unit 101 are performed on a per-terminal-device-50 basis, or collectively on all terminal-devices 50 connected to the base station 20.

[0175] The processing and management in the upper-level processing unit 101 can be performed solely by the upper-level processing unit 101, or it can be obtained from a higher-level node or another base station 20. Furthermore, the processing and management in the upper-level processing unit 101 can be performed separately according to the RAT. For example, the upper-level processing unit 101 can perform processing and management in LTE and processing and management in NR respectively.

[0176] In the RAT control within the upper-level processing unit 101, RAT-related management is performed. For example, in the RAT control, LTE-related management and / or NR-related management are performed. NR-related management includes the setting and processing of parameter sets related to transmitted signals in the NR cell.

[0177] In the radio resource control within the upper-level processing unit 101, the management of configuration information within its own equipment is performed. In the radio resource control within the upper-level processing unit 101, the generation and / or management of downlink data (transmission blocks), system information, RRC messages (RRC parameters), and / or MAC control elements (CE) are performed.

[0178] In the subframe configuration of the upper-level processing unit 101, management of subframe configuration, subframe pattern configuration, uplink / downlink configuration, uplink reference UL-DL configuration and / or downlink reference UL-DL configuration is performed.

[0179] The subframe configuration in the upper-layer processing unit 101 is also called the base station subframe configuration. Furthermore, the subframe configuration in the upper-layer processing unit 101 can be determined based on uplink traffic volume and downlink traffic volume.

[0180] Furthermore, the subframe configuration in the upper-level processing unit 101 can be determined based on the scheduling results of the scheduling control in the upper-level processing unit 101.

[0181] In the scheduling control within the upper-level processing unit 101, the frequency and subframe of the allocated physical channel, the coding rate and modulation scheme of the physical channel, and the transmit power are determined based on the received channel state information, the estimated propagation path input from the channel measurement unit 1059, and the channel quality. For example, the control unit 103 generates control information (DCI format) based on the scheduling results of the scheduling control in the upper-level processing unit 101.

[0182] In the CSI report control of the upper-level processing unit 101, the CSI reports of the terminal device 50 are controlled. For example, settings related to CSI reference resources assumed in the terminal device 50 for calculating CSI are controlled.

[0183] (Control unit)

[0184] The control unit 103 controls the receiving unit 105 and the transmitting unit 107 based on the control information from the upper-level processing unit 101. The control unit 103 generates control information for the upper-level processing unit 101 and outputs the control information to the upper-level processing unit 101.

[0185] The control unit 103 receives the decoded signal from the decoding unit 1051 and the channel estimation result from the channel measurement unit 1059 as inputs. The control unit 103 outputs the signal to be encoded to the encoding unit 1071. Furthermore, the control unit 103 is used to control all or part of the base station 20.

[0186] In addition, the control unit 103 determines the signal waveform (hereinafter also referred to as the use signal waveform) to be used for downlink communication with the terminal device 50 from the single-carrier signal and the multi-carrier signal.

[0187] Control unit 103 controls transmission unit 107 to notify terminal device 50 of information about the signal waveform to be used, using a predetermined signal waveform (e.g., a single-carrier signal). Furthermore, control unit 103 controls transmission unit 107 to perform downlink communication with terminal device 50 using the notified signal waveform.

[0188] (Receiving unit)

[0189] The receiving unit 105 receives signals sent from the terminal device 50 via the transceiver antenna 109 under the control of the control unit 103, further performs receiving processing such as separation, demodulation and decoding, and outputs the processed information to the control unit 103.

[0190] The receiving process in the receiving unit 105 is performed based on predefined settings or settings notified by the base station 20 to the terminal device 50.

[0191] The receiving unit 105 includes a decoding unit 1051, a demodulation unit 1053, a demultiplexing unit 1055, a wireless receiving unit 1057, and a channel measurement unit 1059.

[0192] (Wireless receiver unit)

[0193] The wireless receiving unit 1057 performs the following on the uplink signal received via the transceiver antenna 109: conversion to intermediate frequency (downconversion), removal of unnecessary frequency components, control of amplification level to maintain signal level appropriately, quadrature demodulation based on in-phase and quadrature components of the received signal, conversion from analog to digital signal, removal of guard interval (GI), and / or extraction of frequency domain signal using Fast Fourier Transform (FFT).

[0194] (Demultiplexing unit)

[0195] The demultiplexing unit 1055 separates the uplink channel, such as PUCCH or PUSCH, and / or the uplink reference signal from the signal input from the wireless receiving unit 1057. The demultiplexing unit 1055 outputs the uplink reference signal to the channel measurement unit 1059. Based on the propagation path estimate input from the channel measurement unit 1059, the demultiplexing unit 1055 performs propagation path compensation on the uplink channel.

[0196] (Demodulation unit)

[0197] The demodulation unit 1053 uses modulation schemes such as Binary Phase Shift Keying (BPSK), π / 2 BPSK, Quadrature Phase Shift Keying (QPSK), 16QAM (Quadrature Amplitude Modulation), 64QAM, and 256QAM to demodulate the received signal from the modulation symbols of the uplink channel. The demodulation unit 1053 performs separation and demodulation of the MIMO-multiplexed uplink channel.

[0198] (Decoding unit)

[0199] Decoding unit 1051 performs decoding processing on the coded bits of the demodulated uplink channel. The decoded uplink data and / or uplink control information are output to control unit 103. Decoding unit 1051 performs decoding processing on PUSCH for each transport block.

[0200] (Channel Measurement Unit)

[0201] The channel measurement unit 1059 measures, for example, propagation path estimates and / or channel quality from the uplink reference signal input from the self-demultiplexing unit 1055, and outputs these measurements to the demultiplexing unit 1055 and / or the control unit 103. For example, the channel measurement unit 1059 uses UL-DMRS to measure the propagation path estimates used to perform propagation path compensation on the PUCCH or PUSCH, and uses SRS to measure the channel quality in the uplink.

[0202] (Sending unit)

[0203] The transmitting unit 107 performs transmission processing such as encoding, modulation, and multiplexing on the downlink control information and downlink data input from the upper-level processing unit 101, according to the control from the control unit 103. For example, the transmitting unit 107 generates and multiplexes the PHICH, PDCCH, EPDCCH, PDSCH, and downlink reference signals, and generates a transmission signal.

[0204] The transmission processing in the transmission unit 107 is performed based on predefined settings, settings for notification from the base station 20 to the terminal device 50, or settings for notification via PDCCH or EPDCCH transmitted in the same subframe.

[0205] The transmitting unit 107 includes an encoding unit 1071, a modulation unit 1073, a multiplexing unit 1075, a wireless transmitting unit 1077, and a downlink reference signal generation unit 1079.

[0206] (Encoding unit)

[0207] The encoding unit 1071 encodes the HARQ indicator (HARQ-ACK), downlink control information, and downlink data input from the control unit 103 using a predetermined encoding scheme such as block encoding, convolutional encoding, or turbo encoding.

[0208] (Modulation unit)

[0209] The modulation unit 1073 modulates the coded bits input from the encoding unit 1071 using a predetermined modulation scheme such as BPSK, π / 2BPSK, QPSK, 16QAM, 64QAM or 256QAM.

[0210] (Downlink reference signal generation unit)

[0211] The downlink reference signal generation unit 1079 generates a downlink reference signal based on the physical cell identifier (PCI) and the RRC parameters set in the terminal device 50.

[0212] (Reusable Unit)

[0213] Multiplexing unit 1075 multiplexes the modulation symbols and downlink reference signals of each channel and arranges them in a predetermined resource element.

[0214] (Wireless Transmitting Unit)

[0215] The wireless transmitting unit 1077 performs inverse fast Fourier transform (IFFT) on the signal from the multiplexing unit 1075, converting it to a time-domain signal, adding a guard interval, and generating a digital signal in the baseband. Furthermore, the wireless transmitting unit 1077 performs processes such as conversion to an analog signal, quadrature modulation, conversion (up-conversion) from an intermediate frequency signal to a high-frequency signal, removal of redundant frequency components, and power amplification, and generates a transmitted signal. The transmitted signal output by the wireless transmitting unit 1077 is transmitted from the transceiver antenna 109.

[0216] Here, the wireless transmitting unit 1077 according to this embodiment can support multiple downlink signal waveforms. (Refer to...) Figures 10 to 12 Details describe the wireless transmission unit 1077 in the base station 20 that supports both the first signal waveform (multi-carrier signal) and the second signal waveform (single-carrier signal).

[0217] Figure 10 This is a block diagram illustrating a configuration example of a wireless transmitting unit 1077 according to an embodiment of the present disclosure. The wireless transmitting unit 1077 includes a signal waveform switching unit 401, a first signal waveform transmitting unit 403, and a second signal waveform transmitting unit 405.

[0218] The signal waveform switching unit 401 switches the downlink communication to be transmitted as either the first signal waveform or the second signal waveform according to predetermined conditions or conditions.

[0219] When the downlink communication to be transmitted is a first signal waveform, the first signal waveform transmitting unit 403 performs the transmission processing of the downlink communication. When the downlink communication to be transmitted is a second signal waveform, the second signal waveform transmitting unit 405 performs the transmission processing of the downlink communication. The switching conditions or states in the signal waveform switching unit 401 will be described later.

[0220] The signal waveform switching unit 401 is also called the signal waveform control unit. Furthermore, in Figure 10 In this context, the first signal waveform transmitting unit 403 and the second signal waveform transmitting unit 405 are described as different processing units, but they can be configured as a single processing unit, allowing only a portion of the transmission processing to be switched.

[0221] Figure 11 This is a block diagram illustrating a configuration example of a first signal waveform transmission unit 403 according to an embodiment of the present disclosure. The first signal waveform transmission unit 403 performs transmission processing on a downlink channel and signal to be transmitted by CP-OFDM as an uplink communication signal waveform. The first signal waveform transmission unit 403 includes an S / P unit 4031, an inverse discrete Fourier transform (IDFT) unit 4033, a P / S unit 4035, and a CP insertion unit 4037.

[0222] S / P unit 4031 converts the input serial signal into a parallel signal with a size M. Here, the size M is determined by the size of the frequency domain resources used for downlink communication. The parallel signal with size M is input to IDFT unit 4033 to correspond to a predetermined frequency domain.

[0223] IDFT unit 4033 performs inverse Fourier transform processing on parallel signals of size N. Here, when the size N is a power of 2, the Fourier transform processing can perform inverse fast Fourier transform (IFFT) processing. P / S unit 4035 converts parallel signals of size N into serial signals. CP insertion unit 4037 inserts a predetermined CP for each OFDM symbol.

[0224] Figure 12 This is a block diagram illustrating a configuration example of a second signal waveform transmission unit 405 according to an embodiment of the present disclosure. The second signal waveform transmission unit 405 performs transmission processing on downlink channels and signals to be transmitted as downlink communication signal waveforms by, for example, DFT-S-OFDM.

[0225] The second signal waveform transmission unit 405 includes a DFT unit 4051, an IDFT unit 4053, a P / S unit 4055, and a CP insertion unit 4057. The DFT unit 4051 performs a DFT transform on a parallel signal having a size M. Here, the size M is determined by the size of the frequency domain resources used for downlink communication. The parallel signal having a size M is input to the IDFT unit 4053 to correspond to a predetermined frequency domain.

[0226] IDFT unit 4053 performs inverse Fourier transform processing on parallel signals of size N. Here, when the size N is a power of 2, the Fourier transform processing can perform IFFT processing. P / S unit 4055 converts parallel signals of size N into serial signals. CP insertion unit 4057 inserts a predetermined CP for each DFT-S-OFDM symbol.

[0227] <2-3. Configuration Example of Terminal Device>

[0228] Next, the configuration of terminal device 50 will be described. Terminal device 50 can be interpreted as user equipment (UE) 50.

[0229] Terminal device 50 is a communication device that performs radio communication with another communication device, such as base station 20. Terminal device 50 may be, for example, a mobile phone, a smart device (smartphone or tablet), a personal digital assistant (PDA), or a personal computer. Furthermore, terminal device 50 may be a device with communication capabilities, such as a commercial camera, or a motorcycle, mobile relay vehicle, etc., on which communication devices such as a field pickup unit (FPU) are installed. Additionally, terminal device 50 may be a machine-to-machine (M2M) device or an Internet of Things (IoT) device.

[0230] Terminal device 50 can communicate with base station 20 via NOMA. Furthermore, terminal device 50 can use automatic repeater techniques such as HARQ when communicating with base station 20. Terminal device 50 can also communicate via sidelink with another terminal device 50. When performing sidelink communication, terminal device 50 can use automatic repeater techniques such as HARQ. Terminal device 50 can also perform NOMA communication in communication (sidelink) with another terminal device 50. Additionally, terminal device 50 can communicate via LPWA with another communication device (e.g., base station 20 and another terminal device 50). Furthermore, the radio communication used by terminal device 50 can be millimeter-wave radio communication. The radio communication used by terminal device 50 (including sidelink communication) can be radio communication using radio waves, or it can be radio communication using infrared or visible light (optical wireless communication).

[0231] Furthermore, terminal device 50 can be installed on a mobile device. A mobile device is a portable radio communication device. For example, terminal device 50 can be a vehicle moving on a road, such as a car, bus, truck, or motorcycle; a vehicle moving on rails, such as a train; or a radio communication device installed on such a vehicle. A mobile device can be a mobile terminal, or a mobile device that moves on land (in a narrow sense), underground, on water, or underwater. Additionally, a mobile device can be a mobile device moving within the atmosphere, such as a drone or helicopter, or a mobile device moving outside the atmosphere, such as a satellite.

[0232] Terminal device 50 can simultaneously connect to multiple base stations 20 or multiple cells and perform communication. For example, when a base station 20 supports a communication area via multiple cells (e.g., pCell and sCell), multiple cells can be bundled, and communication can be performed between base station 20 and terminal device 50 using carrier aggregation (CA), dual connectivity (DC), or multiple connectivity (MC) technologies. Alternatively, terminal device 50 and multiple base stations 20 can also perform communication via cells of different base stations 20 using coordinated multipoint transmission and reception (CoMP) technology.

[0233] Figure 13 This is a block diagram illustrating an example configuration of a terminal device 50 according to an embodiment of the present disclosure. Figure 13 As shown, the terminal device 50 includes an upper-level processing unit 201, a control unit 203, a receiving unit 205, a transmitting unit 207, and a transceiver antenna 209.

[0234] Terminal device 50 may support one or more RATs. For example, terminal device 50 may support both LTE and NR. In this case, some or all of the units included in terminal device 50 may be configured separately according to the RAT. For example, receiving unit 205 and transmitting unit 207 may be configured separately for LTE and NR. Furthermore, in an NR cell, Figure 13 Some or all of the units included in the terminal device 50 shown can be configured separately according to a set of parameters related to the transmitted signal. For example, in an NR cell, the radio receiving unit 2057 and the radio transmitting unit 2077 can be configured separately according to a set of parameters related to the transmitted signal.

[0235] (Upper-level processing unit)

[0236] The upper-level processing unit 201 outputs uplink data (transmission blocks) to the control unit 203. The upper-level processing unit 201 performs processing at the Media Access Control layer, Packet Data Convergence Protocol layer, Radio Link Control layer, and Radio Resource Control layer. Furthermore, the upper-level processing unit 201 generates control information for controlling the receiving unit 205 and the transmitting unit 207, and outputs the control information to the control unit 203.

[0237] The upper-level processing unit 201 performs processing and management related to RAT control, radio resource control, subframe configuration, scheduling control, and / or CSI report control. The processing and management in the upper-level processing unit 201 are performed based on predefined settings and / or settings based on control information set or notified from the base station 20.

[0238] For example, control information from base station 20 includes RRC parameters, MAC control elements, or DCI. Furthermore, processing and management in upper-layer processing unit 201 can be performed separately according to RAT. For example, upper-layer processing unit 201 performs processing and management in LTE and processing and management in NR respectively.

[0239] In the RAT control within the upper-level processing unit 201, RAT-related management is performed. For example, in the RAT control, LTE-related management and / or NR-related management are performed. NR-related management includes the setting and processing of parameter sets related to transmitted signals in the NR cell.

[0240] In the radio resource control within the upper-level processing unit 201, the configuration information of its own equipment is managed. In the radio resource control within the upper-level processing unit 201, the generation and / or management of uplink data (transmission blocks), system information, RRC messages (RRC parameters), and / or MAC control elements (CEs) are performed.

[0241] In the subframe configuration of the upper-layer processing unit 201, the subframe configuration of base station 20 and / or base stations different from base station 20 is managed. The subframe configuration includes uplink or downlink configuration for subframes, subframe pattern configuration, uplink / downlink configuration, uplink reference UL-DL configuration, and / or downlink reference UL-DL configuration. The subframe configuration in the upper-layer processing unit 201 is also referred to as the terminal subframe configuration.

[0242] In the scheduling control of the upper-level processing unit 201, control information is generated based on the DCI (scheduling information) from the base station 20 to perform scheduling-related control on the receiving unit 205 and the transmitting unit 207.

[0243] In the CSI reporting control within the upper-level processing unit 201, controls related to reporting CSI to the base station 20 are executed. For example, in the CSI reporting control, settings related to the CSI reference resources assumed in the channel measurement unit 2059 for calculating CSI are controlled. In the CSI reporting control, resources (timing) used for reporting CSI are controlled based on DCI and / or RRC parameters.

[0244] (Control unit)

[0245] The control unit 203 controls the receiving unit 205 and the transmitting unit 207 based on control information from the upper-level processing unit 201. The control unit 203 generates control information for the upper-level processing unit 201 and outputs the control information to the upper-level processing unit 201. The control unit 203 receives the decoded signal from the decoding unit 2051 and the channel estimation result from the channel measurement unit 2059 as inputs. The control unit 203 outputs the signal to be encoded to the encoding unit 2071. Furthermore, the control unit 203 can be used to control all or part of the terminal device 50.

[0246] Furthermore, the control unit 203 obtains information from the base station 20 via the receiving unit 205 regarding the usage signal waveform to be used for downlink communication with the base station 20. This usage signal waveform originates from both single-carrier and multi-carrier signals. The information regarding the usage signal waveform is information transmitted using a predetermined signal waveform (e.g., a single-carrier signal). The control unit 203 controls the receiving unit 205 to perform downlink communication with the base station 20 using this usage signal waveform.

[0247] (Receiving unit)

[0248] The receiving unit 205, under control from the control unit 203, receives signals transmitted from the base station 20 via the transceiver antenna 209, further performs reception processing such as separation, demodulation, and decoding, and outputs the processed information to the control unit 203. The reception processing in the receiving unit 205 is performed based on predefined settings or notifications or settings from the base station 20. The receiving unit 205 includes a decoding unit 2051, a demodulation unit 2053, a demultiplexing unit 2055, a wireless receiving unit 2057, and a channel measurement unit 2059.

[0249] (Wireless receiver unit)

[0250] The wireless receiving unit 2057 performs the following on the uplink signal received via the transceiver antenna 209: conversion to intermediate frequency (downconversion), removal of unnecessary frequency components, control of amplification level to maintain signal level appropriately, quadrature demodulation based on in-phase and quadrature components of the received signal, conversion from analog to digital signal, removal of guard interval, and / or extraction of frequency domain signal using fast Fourier transform.

[0251] Here, the wireless receiving unit 2057 according to this embodiment can support multiple uplink signal waveforms. (Refer to...) Figures 14 to 16 Details are described of the wireless receiving unit 2057 in the terminal device 50 that supports both a first signal waveform (multi-carrier signal) and a second signal waveform (single-carrier signal).

[0252] Figure 14 This is a block diagram illustrating a configuration example of a wireless receiving unit 2057 according to an embodiment of the present disclosure. The wireless receiving unit 2057 includes a signal waveform switching unit 301, a first signal waveform receiving unit 303, and a second signal waveform receiving unit 305.

[0253] The signal waveform switching unit 301 switches between a first signal waveform and a second signal waveform received from the downlink communication according to predetermined conditions or situations. When the received downlink communication is the first signal waveform, the first signal waveform receiving unit 303 performs reception processing on the downlink communication. When the received downlink communication is the second signal waveform, the second signal waveform receiving unit 305 performs reception processing on the downlink communication.

[0254] exist Figure 14 In this context, the first signal waveform receiving unit 303 and the second signal waveform receiving unit 305 are described as different processing units, but they can be configured as a single processing unit, such that only a portion of the receiving processing is switched and executed.

[0255] Figure 15 This is a block diagram illustrating a configuration example of a first signal waveform receiving unit 303 according to an embodiment of the present disclosure. The first signal waveform receiving unit 303 performs reception processing on downlink channels and signals transmitted by CP-OFDM as signal waveforms for downlink communication. The first signal waveform receiving unit 303 includes a CP removal unit 3031, an S / P unit 3033, a DFT unit 3035, and a P / S unit 3037.

[0256] The CP removal unit 3031 removes the cyclic prefix (CP) added to the received downlink communication. The S / P unit 3033 converts the input serial signal into a parallel signal with a magnitude N. The DFT unit 3035 performs Fourier transform processing. Here, when the magnitude N is a power of 2, the Fourier transform processing can perform FFT processing.

[0257] The P / S unit 3037 converts an input parallel signal of size M into a serial signal. Here, the downlink communication signal transmitted by the terminal device 50 performing the receiving process is input to the P / S unit 3037. Furthermore, the size M is determined based on the size of the frequency domain resources used for downlink communication.

[0258] Figure 16 This is a block diagram illustrating a configuration example of a second signal waveform receiving unit 305 according to an embodiment of the present disclosure. The second signal waveform receiving unit 305 performs reception processing on downlink channels and signals transmitted as downlink communication signal waveforms by, for example, DFT-S-OFDM. The second signal waveform receiving unit 305 includes a CP removal unit 3051, an S / P unit 3053, a DFT unit 3055, and an IDFT unit 3057.

[0259] CP removal unit 3051 removes the CP added to the received downlink communication. S / P unit 3053 converts the input serial signal into a parallel signal with a magnitude N. DFT unit 3055 performs Fourier transform processing. Here, when the magnitude N is a power of 2, the Fourier transform processing can perform FFT processing.

[0260] IDFT unit 3057 performs inverse Fourier transform processing on the input signal having a magnitude M. Here, the downlink communication signal transmitted by the terminal device 50 performing the receiving processing is input to IDFT unit 3057. Furthermore, the magnitude M is determined based on the size of the frequency domain resources used for downlink communication.

[0261] (Demultiplexing unit)

[0262] return Figure 13 The demultiplexing unit 2055 separates downlink channels, such as PHICH, PDCCH, EPDCCH, or PDSCH, downlink synchronization signals, and / or downlink reference signals from the signal input from the radio receiving unit 2057. The demultiplexing unit 2055 outputs the downlink reference signal to the channel measurement unit 2059. Based on the propagation path estimate input from the channel measurement unit 2059, the demultiplexing unit 2055 performs propagation path compensation on the downlink channel.

[0263] (Demodulation unit)

[0264] The demodulation unit 2053 uses modulation schemes such as BPSK, π / 2BPSK, QPSK, 16QAM, 64QAM, or 256QAM to demodulate the received signal from the downlink channel modulation symbols. The demodulation unit 2053 performs the separation and demodulation of the MIMO multiplexed downlink channel.

[0265] (Decoding unit)

[0266] Decoding unit 2051 performs decoding processing on the coded bits of the demodulated downlink channel. The decoded downlink data and / or downlink control information are output to control unit 203. Decoding unit 2051 performs decoding processing on PDSCH for each transport block.

[0267] (Channel Measurement Unit)

[0268] The channel measurement unit 2059 measures, for example, the propagation path estimate and / or channel quality from the downlink reference signal input from the self-demultiplexing unit 2055, and outputs it to the demultiplexing unit 2055 and / or the control unit 203.

[0269] The downlink reference signal used for measurement by the channel measurement unit 2059 can be determined at least based on the transmission mode set by the RRC parameters and / or another RRC parameter.

[0270] For example, DL-DMRS measurements are used to estimate the propagation path for performing propagation path compensation on PDSCH or EPDCCH. CRS measurements are used to estimate the propagation path for performing propagation path compensation on PDCCH or PDSCH and / or for channel in the downlink for reporting CSI. CSI-RS measurements are used for channel in the downlink for reporting CSI.

[0271] The channel measurement unit 2059 calculates the reference signal received power (RSRP) and / or reference signal received quality (RSRQ) based on CRS, CSI-RS or detection signals, and outputs them to the upper-level processing unit 201.

[0272] (Sending unit)

[0273] The transmitting unit 207 performs transmission processing such as encoding, modulation, and multiplexing on the uplink control information and uplink data input from the upper-level processing unit 201, according to the control from the control unit 203. For example, the transmitting unit 207 generates and multiplexes uplink channels and / or uplink reference signals such as PUSCH or PUCCH, and generates a transmission signal.

[0274] The transmission processing in the transmission unit 207 is performed based on predefined settings or based on settings or notifications from the base station 20. The transmission unit 207 includes an encoding unit 2071, a modulation unit 2073, a multiplexing unit 2075, a wireless transmission unit 2077, and an uplink reference signal generation unit 2079.

[0275] (Encoding unit)

[0276] The encoding unit 2071 encodes the HARQ indicator (HARQ-ACK), uplink control information, and uplink data input from the control unit 203 using a predetermined encoding scheme such as block encoding, convolutional encoding, or turbo encoding.

[0277] (Modulation unit)

[0278] The modulation unit 2073 modulates the coded bits input from the encoding unit 2071 using a predetermined modulation scheme such as BPSK, π / 2BPSK, QPSK, 16QAM, 64QAM or 256QAM.

[0279] (Uplink reference signal generation unit)

[0280] The uplink reference signal generation unit 2079 generates an uplink reference signal based on, for example, the RRC parameters set in the terminal device 50.

[0281] (Reusable Unit)

[0282] Multiplexing unit 2075 multiplexes the modulation symbols and uplink reference signals of each channel and arranges them in a predetermined resource element.

[0283] (Wireless Transmitting Unit)

[0284] The wireless transmitting unit 2077 performs inverse fast Fourier transform (IFFT) on the signal from the multiplexing unit 2075, converting it to a time-domain signal, adding a guard interval, generating a digital signal in baseband, converting it to an analog signal, and performing quadrature modulation. The wireless transmitting unit 2077 performs processes such as up-conversion from an intermediate frequency signal to a higher frequency signal, removing redundant frequency components, and power amplification, and generates a transmit signal. The transmit signal output by the wireless transmitting unit 2077 is transmitted from the transceiver antenna 209.

[0285] <<3. Operation of the Communication System>>

[0286] Here, examples of measurement-related operations and switching-related operations performed in the communication system SYS1 will be described.

[0287] <3-1. Waveform Information Notification>

[0288] The base station 20 of a neighboring cell or the target cell (target base station) can notify the base station 20 of the serving cell (serving base station) of waveform information about one or more signal waveforms in downlink communication. For example, the control unit 103 of the base station 20 of the neighboring cell or the target cell notifies the base station 20 of the serving cell of waveform information.

[0289] Hereinafter, when distinguishing between waveform information and waveform information included in measurement information, the waveform information notified by the target base station to the serving base station is referred to as the first waveform information, and the waveform information included in the measurement information is referred to as the second waveform information. When not distinguishing between them, they are simply referred to as waveform information.

[0290] (First waveform information)

[0291] The waveform information of the neighboring cell or the target cell includes information about the first signal waveform and / or the second signal waveform.

[0292] The first signal waveform is the signal waveform of the multi-carrier scheme. The second signal waveform is the signal waveform of the single-carrier scheme.

[0293] The first waveform information includes at least one of the following: - Information about whether the signal waveform is valid or invalid - Information about the capabilities of signal waveforms - Information about resources related to applied signal waveforms (Information regarding validity or invalidity) Information regarding the validity or invalidity of a signal waveform includes at least one of information regarding the validity or invalidity of a first signal waveform and information regarding the validity or invalidity of a second signal waveform.

[0294] When the first waveform information includes information indicating that the first signal waveform is valid, the first signal waveform is used for downlink communication of base station 202. That is, the first signal waveform is the usage signal waveform of base station 202. When the first waveform information includes information indicating that the first signal waveform is invalid, the first signal waveform is not used for downlink communication of base station 202. That is, the first signal waveform is not the usage signal waveform of base station 202.

[0295] When the first waveform information includes information indicating that the second signal waveform is valid, the second signal waveform is used for downlink communication of base station 202. That is, the second signal waveform is the usage signal waveform of base station 202. When the first waveform information includes information indicating that the second signal waveform is invalid, the second signal waveform is not used for downlink communication of base station 202. That is, the second signal waveform is not the usage signal waveform of base station 202.

[0296] (Information about abilities)

[0297] Information about the capabilities of the signal waveforms includes at least one of information about the capabilities of the first signal waveform and information about the capabilities of the second signal waveform.

[0298] (Information about resources)

[0299] Information about the resources for applying the signal waveform includes at least one of information about the resources for applying the first signal waveform and information about the resources for applying the second signal waveform.

[0300] (Information about resources for applying the first signal waveform)

[0301] Information about the resources that apply the first signal waveform includes at least one of the following types of information about the resources: - Information about time resources - Information about frequency resources - Information about space resources - Information about physical channels (Time Resources) Time resources include, for example, the resources listed below. However, the resources listed here are merely examples. Resources other than those listed here may also be included in the information regarding the application of the first signal waveform, provided that the resource is time-related.

[0302] - symbol

[0303] - Sub-symbol

[0304] - Time slot

[0305] - Mini time slot

[0306] - Non-time slot

[0307] - Sub-slot

[0308] - Subframe

[0309] - Frame

[0310] - PRACH timing

[0311] (Frequency Resources)

[0312] Frequency resources include, for example, the resources listed below. However, the resources listed herein are merely examples. Resources other than those listed herein may also be included in the information regarding the resources for which the first signal waveform is applied, provided that the resource is frequency-related.

[0313] - Resource elements (including REG, CCE, and CORESET)

[0314] - Resource Block

[0315] - Bandwidth section

[0316] - Component carrier

[0317] - PRACH timing

[0318] - Subcarrier spacing

[0319] (Spatial Resources)

[0320] Spatial resources include, for example, the resources listed below. However, the resources listed herein are merely examples. Resources other than those listed herein may also be included in the information regarding the resources for which the first signal waveform is applied, provided that the resource is spatially related.

[0321] - Physical Cell ID

[0322] - Beam ID

[0323] - Antenna Port

[0324] - Location ID

[0325] - Ephemeral Information

[0326] (Physical channel)

[0327] Physical channels include, for example, the channels listed below. However, the channels listed herein are merely examples. As long as the channel is a physical channel, channels other than those listed herein may also be included in the information regarding the resources applying the first signal waveform.

[0328] - Master synchronization signal

[0329] - Auxiliary synchronization signal

[0330] - PBCH

[0331] - PDSCH

[0332] - PDCCH

[0333] - PUSCH

[0334] - PUCCH

[0335] - PSSCH

[0336] - PSCCH

[0337] - DMRS

[0338] - PTRS

[0339] - PRS

[0340] - SRS

[0341] (Information about resources for applying the second signal waveform)

[0342] Information about the resources for applying the second signal waveform includes at least one of the following resources-related information, for example.

[0343] - Information about time resources

[0344] - Information about frequency resources

[0345] - Information about space resources

[0346] - Information about physical channels

[0347] (Time Resources)

[0348] Time resources include, for example, the resources listed below. However, the resources listed here are merely examples. Resources other than those listed here may also be included in the information regarding the application of the second signal waveform, provided that the resource is time-related.

[0349] - symbol

[0350] - Sub-symbol

[0351] - Time slot

[0352] - Mini time slot

[0353] - Non-time slot

[0354] - Sub-slot

[0355] - Subframe

[0356] - Frame

[0357] - PRACH timing

[0358] (Frequency Resources)

[0359] Frequency resources include, for example, the resources listed below. However, the resources listed here are merely examples. Resources other than those listed here may also be included in the information regarding resources for applying the second signal waveform, provided that the resource is frequency-related.

[0360] - Resource elements (including REG, CCE, and CORESET)

[0361] - Resource Block

[0362] - Bandwidth section

[0363] - Component carrier

[0364] - PRACH timing

[0365] - Subcarrier spacing

[0366] (Spatial Resources)

[0367] Spatial resources include, for example, the resources listed below. However, the resources listed herein are merely examples. Resources other than those listed herein may also be included in the information regarding the application of the second signal waveform, provided that the resource is spatially related.

[0368] - Physical Cell ID

[0369] - Beam ID

[0370] - Antenna Port

[0371] - Location ID

[0372] - Ephemeral Information

[0373] (Physical channel)

[0374] Physical channels include, for example, the channels listed below. However, the channels listed here are merely examples. As long as the channel is a physical channel, channels other than those listed here may also be included in the information regarding the application of the second signal waveform.

[0375] - Master synchronization signal

[0376] - Auxiliary synchronization signal

[0377] - PBCH

[0378] - PDSCH

[0379] - PDCCH

[0380] - PUSCH

[0381] - PUCCH

[0382] - PSSCH

[0383] - PSCCH

[0384] - DMRS

[0385] - PTRS

[0386] - PRS

[0387] - SRS

[0388] (Information about transform precoding)

[0389] Waveform information from neighboring cells or the target cell may include information about transform precoding.

[0390] Information about transform precoding includes at least one of the following:

[0391] - Information regarding the validity or invalidity of transform precoding

[0392] - Information regarding transform precoding capabilities

[0393] - Information about resources where the transformation precoding is valid or invalid.

[0394] (Information regarding validity or invalidity)

[0395] Suppose that the information regarding transform precoding includes information indicating that transform precoding is valid. In this case, base station 202 transmits a signal that has undergone transform precoding, i.e., a signal with a second signal waveform. That is, the second signal waveform is the signal waveform used by base station 202. On the other hand, in this case, base station 202 does not use the first signal waveform for downlink communication.

[0396] Suppose that the information regarding transform precoding includes information indicating that transform precoding is invalid. In this case, base station 202 transmits a signal for which transform precoding has not been applied, i.e., a signal with the first signal waveform. That is, the first signal waveform is the signal waveform used by base station 202. On the other hand, in this case, base station 202 does not use the second signal waveform for downlink communication.

[0397] (Information about resources)

[0398] Since the information regarding resources in which the transform precoding is valid is the same as the information regarding resources applying the second signal waveform described above, its description is omitted. Furthermore, since the information regarding resources in which the transform precoding is invalid is the same as the information regarding resources applying the first signal waveform described above, its description is omitted.

[0399] <3-2. Notification of Measurement Information>

[0400] The base station 20 of the serving cell can notify the terminal device 50 of measurement information regarding downlink communication measurements (measurements of downlink communication quality). For example, the control unit 103 of the base station 20 of the serving cell notifies the terminal device 50 of the measurement information.

[0401] The measurement information includes at least one of the following:

[0402] - Second waveform information

[0403] - Execution Information

[0404] (Second waveform information)

[0405] The waveform information included in the measurement information includes at least a portion of the waveform information (first waveform information) of the target base station (base station 202) and / or the waveform information of the serving base station (base station 201).

[0406] In other words, the serving base station may include at least a portion of the first waveform information obtained from the target base station in the measurement information and notify the terminal device 50 of this at least a portion. Furthermore, the serving base station may include waveform information about the signal waveform it uses in the measurement information and notify the terminal device 50.

[0407] Since the details of the waveform information of the serving base station are the same as those of the first waveform information (which is the same as the first waveform information that interprets the target base station as the serving base station), its description is omitted here.

[0408] (Execution Information)

[0409] The measurement information includes execution information for the terminal device 50 to perform measurements. The execution information includes, for example, execution timing information. The execution timing information is, for example, information about the timing of the measurement execution. The execution timing information may include, for example, at least one of measurement execution request, execution timing, execution cycle, and execution trigger.

[0410] When the timing for the measurement performed by the terminal device 50 is predetermined, the transmission of the timing information can be omitted; in other words, the transmission of the execution information can be omitted.

[0411] Furthermore, the various pieces of information included in the measurement information (e.g., second waveform information and execution information) can be notified to the terminal device 50 from the serving base station at the same time, or they can be notified at different time.

[0412] For example, waveform information of the target base station and waveform information of the serving base station can be notified at the same time (e.g., as the same message). Alternatively, waveform information of the target base station and waveform information of the serving base station can be notified at different time (e.g., as separate messages).

[0413] For example, information about the validity or invalidity of a signal waveform, the capabilities of the signal waveform, and the resources available for using the signal waveform in the waveform information of the target base station can be notified at the same time. Alternatively, this information can be notified at a separate time.

[0414] <3-3. Measurement>

[0415] For example, measurements in terminal device 50 can be performed periodically or non-periodically. When measurements are performed periodically, terminal device 50 performs measurements at predetermined or notified times (or periods). The time for performing measurements can be a time that combines multiple periods. Alternatively, measurements can be performed continuously.

[0416] When measurements are performed non-periodically, the execution information may include measurement execution requests or execution triggers.

[0417] For example, terminal device 50 performs a measurement at a timed interval upon receiving an execution request from the serving base station. When terminal device 50 performs a measurement at a timed interval upon receiving second waveform information, the second waveform information is used as a measurement execution request.

[0418] In this scenario, for example, when terminal device 50 acquires waveform information (first waveform information) of the target base station, terminal device 50 can perform downlink communication measurements with the target base station at the time the waveform information is acquired. Similarly, when terminal device 50 acquires waveform information of the serving base station, terminal device 50 can perform downlink communication measurements with the serving base station at the time the waveform information is acquired.

[0419] Furthermore, for example, terminal device 50 performs measurements according to a predetermined or notified execution trigger. Terminal device 50 performs measurements at a timed interval when the execution trigger is met. The execution trigger includes at least one of, for example, the following triggers.

[0420] - When the scheduled or notified time (moment) has arrived.

[0421] - When the reception quality becomes equal to or lower than a certain level

[0422] - When the movement speed of terminal 50 increases

[0423] - When terminal 50 starts moving

[0424] Terminal device 50 measures, for example, the quality of a downlink signal (e.g., a reference signal). For instance, based on measurement information, terminal device 50 measures the communication quality of at least one of a downlink signal having a first signal waveform and a downlink signal having a second signal waveform. Terminal device 50 uses the downlink signal having the reference signal waveform to measure the downlink communication quality.

[0425] For example, the communication quality of downlink signals may include at least one of the following: Reference Signal Received Power (RSRP), Reference Signal Received Quality (RSRQ), Received Signal Strength Indicator (RSSI), and Signal-to-Interference-plus-Noise Ratio (SINR).

[0426] When the downlink signal waveforms are different, it is conceivable that the communication quality measured for each signal waveform will be different. Therefore, as described above, the terminal device 50 can measure the communication quality of the downlink signal for each signal waveform.

[0427] That is, the base station 20 transmits a first signal having a first signal waveform and used for downlink communication measurement, and a second signal having a second signal waveform and used for downlink communication measurement.

[0428] The first and second signals are synchronization signal blocks. Base station 20 can, for example, transmit an independent SSB (Synchronization Signal (SS) / Physical Broadcast Channel (PBCH) block) for each signal waveform. For example, base station 20 can transmit a primary synchronization signal (PSS), secondary synchronization signal (SSS), PBCH, or SSB for multi-carrier signals, and a PSS, SSS, PBCH, or SSB for single-carrier signals.

[0429] Alternatively, the first and second signals can be reference signals for downlink signals. For example, base station 20 can transmit a Channel State Information Reference Signal (CSI-RS) for each signal waveform. For example, base station 20 can transmit a CSI-RS for multi-carrier signals and a CSI-RS for single-carrier signals.

[0430] In this case, base station 20 can use multiple signal waveforms to transmit the same (common) PSS, SSS, PBCH or SSB.

[0431] <3-4. Measurement Report>

[0432] For example, the measurement results in terminal device 50 are reported (feedback) to the serving base station as a measurement report. Terminal device 50 reports the measurement results of the downlink signal to the serving base station. Terminal device 50 reports at least one of the measurement results of the downlink signal having a first signal waveform and the measurement results of the downlink signal having a second signal waveform.

[0433] For example, when the second waveform information includes information about transform precoding, the terminal device 50 reports at least one of the measurement results when transform precoding is valid and the measurement results when transform precoding is invalid.

[0434] For example, terminal device 50 reports at least one of the following information as a measurement result to the serving base station.

[0435] - SS-RSRP

[0436] - CSI-RSRP

[0437] - SS-RSRQ

[0438] - CSI-RSRQ

[0439] - SS-RSSI

[0440] - CSI-RSSI

[0441] - SS-SINR

[0442] - CSI-SINR

[0443] Terminal device 50 can report the communication quality measurement results of downlink signals of multiple signal waveforms as a unified measurement report to the serving base station, or it can report the results as a separate measurement report for each signal waveform to the serving base station.

[0444] Terminal device 50 executes measurement reports, for example, periodically or non-periodically (based on a triggering time).

[0445] When periodically executing measurement reports, the terminal device 50 executes the measurement reports at predetermined time intervals (or periods).

[0446] When a measurement report is executed non-periodically (event-triggered), the terminal device 50 executes the measurement report at the time when it receives the measurement report execution request or at the time when the report execution trigger is met.

[0447] For example, terminal device 50 executes a measurement report at a timed interval after receiving a measurement report execution request from the serving base station. The measurement report execution request can be the same as the measurement execution request.

[0448] In other words, when terminal device 50 receives a measurement execution request from the serving base station, terminal device 50 performs the measurement and notifies the serving base station of the measurement report.

[0449] Furthermore, for example, terminal device 50 executes a measurement report based on a predetermined or notified report execution trigger. Terminal device 50 executes the measurement report at a timed interval when the report execution trigger is met.

[0450] Examples of report execution triggers may include situations where the communication quality (e.g., RSRP) of downlink signals transmitted from the target base station becomes equal to or greater than a threshold. Hereinafter, the communication quality of downlink signals transmitted from the target base station is also referred to as the target communication quality.

[0451] For example, when the target communication quality of the measured first signal waveform (or a signal waveform in which the transformation precoding is invalid) is equal to or greater than a threshold, the terminal device 50 reports the measurement result to the serving base station.

[0452] In addition, for example, when the target communication quality of the measured second signal waveform (or the signal waveform in which the transformation precoding is valid) is equal to or greater than a threshold, the terminal device 50 reports the measurement result to the serving base station.

[0453] Examples of report execution triggers may include situations where the communication quality (e.g., RSRP) of downlink signals transmitted from the serving base station becomes equal to or greater than a threshold. Hereinafter, the communication quality of downlink signals transmitted from the serving base station is also referred to as service communication quality.

[0454] For example, when the service communication quality of the measured first signal waveform (or a signal waveform in which the transformation precoding is invalid) is equal to or greater than a threshold, the terminal device 50 reports the measurement result to the serving base station.

[0455] In addition, for example, when the service communication quality of the measured second signal waveform (or the signal waveform in which the transformation precoding is valid) is equal to or greater than a threshold, the terminal device 50 reports the measurement result to the serving base station.

[0456] Examples of report execution triggers may include triggering based on the difference between the target communication quality of a first signal waveform (or a signal waveform in which a pre-coded invalid transformation is performed) and the target communication quality of a second signal waveform (or a signal waveform in which a pre-coded valid transformation is performed).

[0457] For example, when the target communication quality of the measured first signal waveform is equal to or greater than the offset, or equal to or less than the offset, relative to the target communication quality of the measured second signal waveform, the terminal device 50 reports the measurement result to the serving base station.

[0458] For example, when the target communication quality of the measured second signal waveform is equal to or greater than the offset, or equal to or less than the offset, relative to the target communication quality of the measured first signal waveform, the terminal device 50 reports the measurement result to the serving base station.

[0459] For example, when the target communication quality of the measured first signal waveform is higher (or lower) than the target communication quality of the measured second signal waveform, the terminal device 50 reports the measurement result to the serving base station.

[0460] Examples of report execution triggers include triggering based on changes in target communication quality based on a first signal waveform (or a signal waveform in which pre-coding is invalid) and a second signal waveform (or a signal waveform in which pre-coding is valid).

[0461] For example, when the target communication quality of the first signal waveform becomes lower than the first threshold and / or the target communication quality of the second signal waveform becomes higher than the second threshold, the terminal device 50 reports the measurement results to the serving base station.

[0462] For example, examples of report execution triggers include triggering based on the difference between the service communication quality and the target communication quality.

[0463] For example, examples of report execution triggering include the following situation: the service communication quality of the first signal waveform (or the signal waveform in which the transformation precoding is invalid) becomes equal to or lower than the target communication quality relative to at least one of the first signal waveform and the second signal waveform (or the signal waveform in which the transformation precoding is valid).

[0464] Alternatively, examples of report execution triggering include the following situation: the service communication quality of the second signal waveform becomes equal to or lower than the offset relative to the target communication quality of at least one of the first and second signal waveforms.

[0465] Alternatively, examples of report execution triggering include situations where the service communication quality of at least one of the first and second signal waveforms becomes equal to or lower than the offset relative to the target communication quality of the first signal waveform.

[0466] Alternatively, examples of report execution triggering include situations where the service communication quality of at least one of the first and second signal waveforms becomes equal to or lower than the offset relative to the target communication quality of the second signal waveform.

[0467] Here, when terminal device 50 reports communication quality across multiple signal waveforms to the serving base station, there may be trigger conditions that are met in multiple signal waveforms. In this case, terminal device 50 can, for example, notify the serving base station of measurement reports related to all signal waveforms for which measurements have been performed.

[0468] Alternatively, terminal device 50 may execute a measurement report, for example, based on the priority of the signal waveforms. For instance, when the priority of the first signal waveform is higher than the priority of the second signal waveform, terminal device 50 notifies the serving base station of a measurement report of the downlink signal of the first signal waveform.

[0469] This priority can be determined statically, for example, based on standards, or semi-statically, through notifications from the serving base station, etc. For example, when the priority is determined semi-statically, the serving base station pre-sets in the terminal device 50 which signal waveform measurement report to prioritize.

[0470] Furthermore, report execution triggers are not limited to the signal waveform-related triggers mentioned above.

[0471] For example, examples of report execution triggering include situations where the communication quality (e.g., RSRP) of a neighboring cell (e.g., the target cell) becomes equal to or greater than the offset relative to the communication quality (e.g., RSRP) of the belonging cell (e.g., the serving cell).

[0472] For example, a scenario where the communication quality of a neighboring cell becomes higher than that of the cell in which the report is generated could be triggered.

[0473] For example, a scenario where the communication quality of the home cell falls below a first threshold and the communication quality of neighboring cells rises above a second threshold could be triggered.

[0474] For example, a report execution trigger could be triggered when the quality of a reference signal (e.g., CSI-RS) resource becomes higher than a threshold.

[0475] For example, examples of report execution triggering include situations where the moving speed of terminal device 50 becomes equal to or greater than a threshold. For example, examples of report execution triggering include situations where the moving speed of terminal device 50 becomes equal to or less than a threshold.

[0476] Terminal device 50 can determine the signal waveform to be measured based on measurement information. Alternatively, when a default signal waveform to be measured is determined, terminal device 50 can, for example, determine based on measurement information whether to perform a measurement and measurement report on a signal waveform that was not determined as the default.

[0477] For example, suppose the first signal waveform is determined as the default signal waveform to be measured in the target cell. In this case, the terminal device 50 determines whether to perform a measurement of the downlink signal with the second signal waveform in the target cell based on whether waveform information about the second signal waveform of the target cell is included in the measurement information. When waveform information about the second signal waveform of the target cell is included in the measurement information, the terminal device 50 performs a measurement of the downlink signal with the second signal waveform in the target cell.

[0478] Alternatively, terminal device 50 can determine whether to perform a measurement of the downlink signal with the second signal waveform in the target cell based on whether the waveform information of the target cell is included in the measurement information. When the waveform information of the target cell is included in the measurement information, terminal device 50 performs a measurement of the downlink signal with the second signal waveform in the target cell.

[0479] For example, the serving base station can determine whether to cause the terminal device 50 to perform a measurement of the downlink signal with the second signal waveform in the target cell, based on whether it has already obtained the first waveform information (or the first waveform information about the second signal waveform) from the target base station.

[0480] For example, when the serving base station has not yet obtained the first waveform information from the target base station, the serving base station determines not to instruct the terminal device 50 to perform a measurement of the downlink signal with the second signal waveform in the target cell. In this case, for example, the serving base station notifies the terminal device 50 of measurement information that does not include the first waveform information (or the first waveform information regarding the second signal waveform).

[0481] For example, suppose the second signal waveform is determined as the default signal waveform to be measured in the target cell. In this case, the terminal device 50 determines whether to perform a measurement of the downlink signal with the first signal waveform in the target cell based on whether waveform information about the first signal waveform of the target cell is included in the measurement information. When waveform information about the first signal waveform of the target cell is included in the measurement information, the terminal device 50 performs a measurement of the downlink signal with the first signal waveform in the target cell.

[0482] Alternatively, terminal device 50 can determine whether to perform a measurement of the downlink signal with the first signal waveform in the target cell based on whether the waveform information of the target cell is included in the measurement information. When the waveform information of the target cell is included in the measurement information, terminal device 50 performs a measurement of the downlink signal with the first signal waveform in the target cell.

[0483] For example, the serving base station can determine whether to cause the terminal device 50 to perform a measurement of the downlink signal with the first signal waveform in the target cell, based on whether it has already obtained the first waveform information (or the first waveform information about the first signal waveform) from the target base station.

[0484] For example, when the serving base station has not yet obtained the first waveform information (or first waveform information about the first signal waveform) from the target base station, the serving base station determines not to instruct the terminal device 50 to perform a measurement of the downlink signal with the first signal waveform in the target cell. In this case, for example, the serving base station notifies the terminal device 50 of measurement information that does not include the first waveform information (or first waveform information about the first signal waveform).

[0485] The target cell described herein can be appropriately interpreted as the serving cell. Furthermore, the first signal waveform can be appropriately interpreted as a signal waveform in which the transform precoding is set to invalid. Furthermore, the second signal waveform can be appropriately interpreted as a signal waveform in which the transform precoding is set to valid.

[0486] <3-5. Switching Decision>

[0487] The serving base station determines whether to perform a handover of the terminal device 50 based on the measurement report from the terminal device 50.

[0488] For example, when the target communication quality of the first signal waveform becomes equal to or greater than a threshold, the serving base station determines that a handover should be performed. Similarly, when the target communication quality of the second signal waveform becomes equal to or greater than a threshold, the serving base station determines that a handover should be performed.

[0489] For example, when the service communication quality of the first signal waveform becomes equal to or less than a threshold, the serving base station determines that a handover should be performed. Similarly, when the service communication quality of the second signal waveform becomes equal to or less than a threshold, the serving base station determines that a handover should be performed.

[0490] For example, when the target communication quality of the first signal waveform is equal to or greater than the offset, or equal to or less than the offset, relative to the target communication quality of the second signal waveform, the serving base station determines that a handover should be performed.

[0491] For example, when the target communication quality of the second signal waveform is equal to or greater than the offset, or equal to or less than the offset, relative to the target communication quality of the first signal waveform, the serving base station determines that a handover should be performed.

[0492] For example, when the target communication quality of the first signal waveform is higher (or lower) than the target communication quality of the second signal waveform, the serving base station determines that a handover should be performed.

[0493] Examples of switching criteria include triggering based on changes in the target communication quality of a first signal waveform and changes in the target communication quality of a second signal waveform.

[0494] For example, when the target communication quality of the first signal waveform becomes lower than a first threshold and / or the target communication quality of the second signal waveform becomes higher than a second threshold, the serving base station determines that a handover should be performed.

[0495] For example, examples of handover criteria include criteria based on the difference between the quality of service communication and the quality of target communication.

[0496] For example, when the service communication quality of the first signal waveform (or the signal waveform in which the transformation precoding is invalid) becomes equal to or lower than the target communication quality of at least one of the first signal waveform and the second signal waveform (or the signal waveform in which the transformation precoding is valid), the serving base station determines to perform a handover.

[0497] Alternatively, when the service communication quality of the second signal waveform becomes equal to or lower than the target communication quality of at least one of the first and second signal waveforms, the serving base station determines that a handover should be performed.

[0498] Alternatively, when the service communication quality of at least one of the first and second signal waveforms becomes equal to or lower than the offset relative to the target communication quality of the first signal waveform, the serving base station determines that a handover should be performed.

[0499] Alternatively, when the service communication quality of at least one of the first and second signal waveforms becomes equal to or lower than the offset relative to the target communication quality of the second signal waveform, the serving base station determines that a handover should be performed.

[0500] Therefore, the serving base station determines the handover to be performed based on at least one of the service communication quality of the first signal waveform, the service communication quality of the second signal waveform, the target communication quality of the first signal waveform, and the target communication quality of the second signal waveform.

[0501] <3-6. Instruction Information>

[0502] The serving base station that has determined to perform the handover notifies the terminal device 50 of instruction information (e.g., a handover command).

[0503] The instruction information (example of switching information) includes at least one of the following.

[0504] - Waveform information of the target cell

[0505] - Information about the handover process

[0506] - Measurement Information

[0507] - Information regarding measurement reports

[0508] The waveform information of the target cell includes at least a portion of the aforementioned first waveform information. The serving base station may use the first waveform information obtained from the target base station for measurement as the waveform information of the target cell. Alternatively, the serving base station may obtain the first waveform information from the target base station before notifying the instruction information.

[0509] Furthermore, the waveform information of the target cell may include information indicating which signal waveform is used to perform the handover procedure (e.g., a random access procedure). For example, the serving base station may indicate to the terminal device 50 which signal waveform is used to perform the handover procedure by including first waveform information about the signal waveform used for the handover procedure in the waveform information of the target cell.

[0510] Information regarding the switching process includes at least one of the following:

[0511] - PRACH transmission resources for the target cell

[0512] - PRACH transmission preamble sequence for the target cell

[0513] - Target community's community ID

[0514] - Uplink / downlink carrier frequencies of the target cell

[0515] - Bandwidth of the target cell

[0516] - The new terminal's unique ID (C-RNTI)

[0517] - Post-switching radio resource configuration

[0518] - Conditions used for updating and switching related information sets

[0519] - Trigger information used to perform the switch

[0520] - Target cell advance time information

[0521] - SSB index of the target cell

[0522] - Information about sending weights

[0523] - Information regarding the 2-step initial access

[0524] The measurement information may be the same as the measurement information notified by the serving base station to the terminal device 50 regarding the aforementioned measurement. Alternatively, for example, the measurement information here may be the aforementioned execution information.

[0525] In addition, the information regarding the measurement report includes information used by the terminal device 50 to execute the measurement report. This information may include information about the priority of the signal waveform being reported, information about the triggering of report execution, etc.

[0526] The terminal device 50, having already acquired instruction information, performs a handover process from the serving base station to the target base station based on the acquired instruction information. For example, the terminal device 50 uses a signal waveform specified by the waveform information of the target cell included in the instruction information to perform the handover process.

[0527] Here, we assume the instruction information is a handover command, meaning the handover command includes waveform information of the target cell; however, the instruction information may not be the handover command itself. For example, the instruction information may include both the handover command and the waveform information of the target cell.

[0528] Therefore, the handover command and the waveform information of the target cell can be different information (information sent separately). The waveform information of the target cell can be notified to the terminal device 50 at the same time as the handover command, or it can be notified at a different time (e.g., before the handover command).

[0529] Alternatively, when the waveform information of the target cell is the same as the waveform information included in the measurement information used for measurement, the notification of the target cell's waveform information can be omitted. In this case, the terminal device 50 performs the handover based on the waveform information included in the measurement information.

[0530] In this case, the measurement information included in the instruction information can be included in the waveform information of the handover command or the target cell.

[0531] Alternatively, the measurement information can be included separately from the handover command and the waveform information of the target cell in the instruction information. In this case, the measurement information can be notified to the terminal device 50 at the same timing as at least one of the handover command and the waveform information of the target cell, or it can be notified at a different timing.

[0532] The measurement information here (the measurement information included in the instruction information) can be interpreted as the information about the measurement report included in the instruction information.

[0533] <3-7. Conditional Switching>

[0534] When a conditional handover is performed in the communication system SYS1, the serving base station notifies the terminal device 50 of information about the conditional handover (example of conditional handover information) as instruction information.

[0535] Information regarding conditional switching includes at least one of the following:

[0536] - Waveform information of neighboring cells

[0537] - Process information regarding conditional switching procedures

[0538] - Trigger information regarding conditional switching

[0539] - Separation information regarding the execution of separation from the serving base station.

[0540] - Measurement Information

[0541] - Information regarding measurement reports

[0542] The waveform information of neighboring cells includes information similar to that of the target cell. The waveform information of neighboring cells includes the first waveform information of the candidate base station 20 for the target cell. Here, neighboring cells may include one or more neighboring cells. That is, the waveform information of neighboring cells includes the first waveform information of one or more candidate base stations 20 for the target cell.

[0543] The process information regarding the conditional switching process includes at least one of the following:

[0544] - PRACH transmission resources for target cell candidates

[0545] - PRACH transmission preamble sequence for target cell candidate

[0546] - Target cell candidate cell ID

[0547] - Uplink / downlink carrier frequencies of the target cell candidate

[0548] - Bandwidth of target cell candidates

[0549] - The new terminal's unique ID (C-RNTI)

[0550] - Post-switching radio resource configuration

[0551] - Conditions used for updating and switching related information sets

[0552] - Trigger information used to perform the switch

[0553] - Target cell candidate timing advance information

[0554] - SSB index of target cell candidates

[0555] - Information about sending weights

[0556] - Information regarding the 2-step initial access

[0557] The trigger information for conditional switching includes at least one of the following: information about waveform execution triggering related to waveform information and information about execution triggering.

[0558] Examples of waveform execution triggering can include situations where the communication quality of downlink signals transmitted from the target base station (such as the target communication quality of RSRP) becomes equal to or greater than a threshold.

[0559] For example, when the target communication quality of the measured first signal waveform (or a signal waveform in which the transformation precoding is invalid) is equal to or greater than a threshold, the terminal device 50 performs a conditional handover.

[0560] Furthermore, for example, when the target communication quality of the measured second signal waveform (or the signal waveform in which the transformation pre-coded is valid) is equal to or greater than a threshold, the terminal device 50 performs a conditional handover.

[0561] Examples of waveform execution triggering can include situations where the communication quality of downlink signals sent from the serving base station (such as the service communication quality of RSRP) becomes equal to or greater than a threshold.

[0562] For example, when the service communication quality of the measured first signal waveform (or a signal waveform in which the transformation precoding is invalid) is equal to or greater than a threshold, the terminal device 50 performs a conditional handover.

[0563] Furthermore, for example, when the service communication quality of the measured second signal waveform (or the signal waveform in which the transformation pre-coded is valid) is equal to or greater than a threshold, the terminal device 50 performs a conditional handover.

[0564] Examples of waveform execution triggering may include triggering based on the difference between the target communication quality of a first signal waveform (or a signal waveform in which pre-coded invalid transformations are performed) and the target communication quality of a second signal waveform (or a signal waveform in which pre-coded valid transformations are performed).

[0565] For example, when the target communication quality of the measured first signal waveform is equal to or greater than the offset, or equal to or less than the offset, the terminal device 50 performs a conditional handover.

[0566] For example, when the target communication quality of the measured second signal waveform is equal to or greater than the offset, or equal to or less than the offset, relative to the target communication quality of the measured first signal waveform, the terminal device 50 performs a conditional handover.

[0567] For example, when the target communication quality of the measured first signal waveform is higher (or lower) than the target communication quality of the measured second signal waveform, the terminal device 50 performs a conditional handover.

[0568] Examples of waveform execution triggering may include triggering based on changes in the target communication quality of a first signal waveform (or a signal waveform in which pre-coded invalid transformations are performed) and changes in the target communication quality of a second signal waveform (or a signal waveform in which pre-coded valid transformations are performed).

[0569] For example, when the target communication quality of the first signal waveform becomes lower than the first threshold and / or the target communication quality of the second signal waveform becomes higher than the second threshold, the terminal device 50 performs a conditional handover.

[0570] For example, waveform execution triggering could include triggering based on the difference between the service communication quality and the target communication quality.

[0571] For example, waveform execution triggering includes situations where the service communication quality of a first signal waveform (or a signal waveform in which the transformation precoding is invalid) becomes equal to or lower than the target communication quality relative to at least one of the first signal waveform and the second signal waveform (or a signal waveform in which the transformation precoding is valid).

[0572] Alternatively, examples of waveform execution triggering include the following situation: the service communication quality of the second signal waveform becomes equal to or lower than the offset relative to the target communication quality of at least one of the first and second signal waveforms.

[0573] Alternatively, examples of waveform execution triggering include situations where the service communication quality of at least one of the first and second signal waveforms becomes equal to or lower than the offset relative to the target communication quality of the first signal waveform.

[0574] Alternatively, examples of waveform execution triggering include situations where the service communication quality of at least one of the first and second signal waveforms becomes equal to or lower than the offset relative to the target communication quality of the second signal waveform.

[0575] The first signal waveform triggered by waveform execution is appropriately interpreted as a signal waveform in which the transform precoding is invalid. Furthermore, the second signal waveform triggered by waveform execution is appropriately interpreted as a signal waveform in which the transform precoding is valid.

[0576] Information about the execution trigger may include at least one of the following:

[0577] - RSRP information of target cell candidates

[0578] - RSRQ information of target cell candidates

[0579] - RSSI information of target cell candidates

[0580] - Timer information regarding the execution of handover for target cell candidates

[0581] - Information regarding the start time of the handover execution for the target cell candidate.

[0582] - Information regarding the start time of the detection operation for handover execution triggering (e.g., waveform execution triggering) of the target cell candidate.

[0583] - Information regarding the actions to take after the timer expires related to the handover execution with the target cell candidate.

[0584] - Information regarding operations when a synchronization signal is received from a cell other than the target cell candidate.

[0585] Separation information regarding the execution of separation from the serving base station may include at least one of the following.

[0586] - RSRP information of the serving cell

[0587] - RSRQ information for the serving cell

[0588] - RSSI information of the serving cell

[0589] - Information about the timer used to perform separation from the serving cell

[0590] - Information regarding the timing of the separation from the serving cell

[0591] - Information regarding the implementation of separation from the serving cell

[0592] The measurement information and information about the measurement report can be the same as the measurement information and information about the measurement report included in the aforementioned instruction information. In this case, the target cell of the instruction information can be appropriately interpreted as a target cell candidate (or neighboring cell). Furthermore, the target base station of the instruction information can be appropriately interpreted as a target base station candidate.

[0593] One or more pieces of information included in the process information regarding the conditional handover process can be sent to the terminal device 50 as a single message (or notification), or they can be notified separately.

[0594] <<4. Examples of Communication Processing>>

[0595] Here, the handover process and conditional handover process are described as examples of communication processes performed in the communication system SYS1.

[0596] <4-1. Switching Process>

[0597] Figure 17 This is a sequence diagram illustrating an example of the switching process according to embodiments of the present disclosure. Figure 17 In the switching process, with Figure 5 The same processing is indicated by the same reference numerals in the accompanying drawings, and its description is omitted.

[0598] like Figure 17 As shown, the serving base station obtains waveform information from the target base station (step S301). This waveform information corresponds to the first waveform information mentioned above. The waveform information includes at least one of information about the first signal waveform and information about the second signal waveform.

[0599] The serving base station notifies the terminal device 50 of measurement information based on the acquired waveform information (step S302). The measurement information includes waveform information about the signal waveforms of at least one of the target cell and the serving cell.

[0600] Terminal device 50 performs measurement (measurement control) based on measurement information and sends a measurement report to the serving base station (step S303). Similarly, terminal device 50 performs measurement based on measurement information and sends a measurement report to the target base station (step S304).

[0601] Here, terminal device 50 reports a measurement report to the target base station, but terminal device 50 may, for example, send a measurement report related to the communication quality of the downlink signal of the target base station to the serving base station.

[0602] Subsequently, after step S106, the serving base station that has determined to perform the handover sends an RRC reconfiguration including a handover command (step S305) and notifies the execution of the handover. The handover command includes, for example, waveform information of the target cell.

[0603] Terminal device 50 performs the handover according to the handover command.

[0604] <4-2. Conditional Switching Processing>

[0605] Figure 18 This is a sequence diagram illustrating an example of a conditional switching process according to embodiments of the present disclosure. Figure 18 In the conditional handover process, with Figure 6 The same processing is indicated by the same reference numerals in the accompanying drawings, and its description is omitted.

[0606] like Figure 18 As shown, the serving base station obtains waveform information from the first target base station and the second target base station (step S401). This waveform information corresponds to the first waveform information mentioned above. The waveform information includes at least one of information about the first signal waveform and information about the second signal waveform.

[0607] The serving base station notifies the terminal device 50 of measurement information based on the acquired waveform information (step S402). The measurement information includes waveform information about at least one signal waveform of the target candidate cells #1 and #2 and the serving cell.

[0608] Terminal device 50 performs measurement (measurement control) based on measurement information and sends a measurement report to the serving base station (step S403).

[0609] Subsequently, after step S208, the serving base station that has determined to perform conditional handover sends an RRC reconfiguration to the terminal device 50 (step S404). The RRC reconfiguration includes, for example, information about the conditional handover.

[0610] Terminal device 50 performs conditional handover based on information regarding conditional handover.

[0611] Therefore, by acquiring waveform information from the target base station (or the first target base station and the second target base station) through the serving base station and notifying the terminal device 50 of the waveform information, the terminal device 50 is able to measure the communication quality of the downlink signal even when using multiple signal waveforms.

[0612] The serving base station can perform processing (e.g., handover determination) based on the communication quality of the downlink signal obtained from the terminal device 50.

[0613] Therefore, the communication system SYS1 is able to measure the quality of downlink signals in communication using multiple signal waveforms, and can perform more efficient communication using multiple signal waveforms.

[0614] <<5. Correlation of Signal Waveforms>>

[0615] For example, downlink signal waveforms and uplink signal waveforms can have the following correlations.

[0616] For example, when a second signal waveform is set in downlink communication, a second signal waveform is also set in uplink communication.

[0617] In this case, terminal device 50 assumes that the second signal waveform set in downlink communication is also set in uplink communication. That is, when the second signal waveform is set in downlink communication, terminal device 50 assumes that the first signal waveform is not set in uplink communication.

[0618] For example, when considering coverage areas such as cell edges, it is assumed that the first signal waveform is set in both the uplink and downlink.

[0619] For example, when a first signal waveform is set in downlink communication, a first signal waveform is also set in uplink communication.

[0620] In this case, terminal device 50 assumes that the first signal waveform set in downlink communication is also set in uplink communication. That is, when the first signal waveform is set in downlink communication, terminal device 50 assumes that the second signal waveform is not set in uplink communication.

[0621] Therefore, for example, within the coverage area where communication using the first signal waveform is possible in downlink communication, it is assumed that communication using the first signal waveform is also performed in uplink communication.

[0622] Alternatively, when the first signal waveform is set in downlink communication, the first signal waveform and / or the second signal waveform are set in uplink communication.

[0623] In this case, terminal device 50 assumes that when the first signal waveform is set in downlink communication, the first signal waveform and / or the second signal waveform are set in uplink communication.

[0624] For example, when a second signal waveform is set in uplink communication, a second signal waveform is also set in downlink communication.

[0625] In this case, terminal device 50 assumes that the second signal waveform set in the uplink communication is also set in the downlink communication. That is, when the second signal waveform is set in the uplink communication, terminal device 50 assumes that the first signal waveform is not set in the downlink communication.

[0626] For example, when considering coverage areas such as cell edges, it is assumed that the first signal waveform is set in both the uplink and downlink.

[0627] For example, when a first signal waveform is set in uplink communication, a first signal waveform is also set in downlink communication.

[0628] In this case, terminal device 50 assumes that the first signal waveform set in the uplink communication is also set in the downlink communication. That is, when the first signal waveform is set in the uplink communication, terminal device 50 assumes that the second signal waveform is not set in the downlink communication.

[0629] Therefore, for example, within the coverage area where communication using the first signal waveform is possible in uplink communication, it is assumed that communication using the first signal waveform is also performed in downlink communication.

[0630] Alternatively, when the first signal waveform is set in the uplink communication, the first signal waveform and / or the second signal waveform are set in the downlink communication.

[0631] In this case, terminal device 50 assumes that when the first signal waveform is set in the uplink communication, the first signal waveform and / or the second signal waveform are set in the downlink communication.

[0632] <<6. Examples of Signal Waveforms>>

[0633] In the above embodiments, the first signal waveform is CP-OFDM and the second signal waveform is DFT-S-OFDM, but the signal waveforms are not limited to these examples.

[0634] For example, the first signal waveform can be any signal waveform of the multi-carrier scheme. For example, the multi-carrier scheme can include the following schemes.

[0635] - Cyclic prefix-orthogonal frequency division multiplexing with weighted overlapping summation (CP-OFDM with WOLA)

[0636] - Universal Filtered Multicarrier (UFMC)

[0637] - Filter Bank Multicarrier (FBMC)

[0638] - Generalized Frequency Division Multiplexing (GFDM)

[0639] For example, the second signal waveform can be any signal waveform of the single-carrier scheme. For example, the single-carrier scheme can include the following schemes.

[0640] - Constant envelope

[0641] - Single-carrier quadrature amplitude modulation (SC-QAM)

[0642] - Single-carrier modulation with frequency domain equalization (SC-FDE)

[0643] - Single-carrier frequency division multiplexing (SC-FDM)

[0644] - Zero Tail SC-FDM

[0645] <<7. Examples of Hardware Configurations>>

[0646] Next, examples of hardware configurations for the base station 20 and terminal device 50 according to various embodiments will be described. The information devices of the aforementioned base station 20 and terminal device 50 are, for example, composed of... Figure 19 The computer 1000 with the configuration shown is implemented.

[0647] Figure 19 This is a block diagram illustrating an example of the hardware configuration of a computer 1000 according to the present disclosure. The computer 1000 includes a CPU 1100, RAM 1200, ROM 1300, hard disk drive (HDD) 1400, communication interface 1500, and input / output interface 1600. The various units of the computer 1000 are connected by a bus 1050.

[0648] The CPU 1100 operates based on programs stored in ROM 1300 or HDD 1400 and controls the various units. For example, the CPU 1100 expands programs stored in ROM 1300 or HDD 1400 in RAM 1200 and executes processing corresponding to various programs.

[0649] ROM 1300 stores startup programs such as the Basic Input / Output System (BIOS) executed by CPU 1100 when computer 1000 starts up, and programs that depend on the hardware of computer 1000.

[0650] HDD 1400 is a computer-readable recording medium that non-transitorily records programs executed by CPU 1100, data used by such programs, etc. Specifically, HDD 1400 is a recording medium that records programs according to the present disclosure, such as program data 1450.

[0651] Communication interface 1500 is an interface for connecting computer 1000 to an external network 1550 (e.g., the Internet). For example, CPU 1100 receives data from another device via communication interface 1500 and sends data generated by CPU 1100 to that other device.

[0652] Input / output interface 1600 is an interface for connecting input / output device 1650 to computer 1000. For example, CPU 1100 receives data from input devices such as keyboards or mice via input / output interface 1600. Furthermore, CPU 1100 sends data to output devices such as monitors, speakers, or printers via input / output interface 1600. Additionally, input / output interface 1600 can be used as a media interface for reading programs recorded on a predetermined recording medium. Such media include, for example, optical recording media such as digital versatile discs (DVDs, registered trademarks) or phase-change rewritable discs (PDs), magneto-optical recording media such as magneto-optical discs (MOs), magnetic tape media, magnetic recording media, or semiconductor memory.

[0653] The CPU 1100 implements the functions of control units 103 and 203, etc., by executing programs loaded on RAM 1200. Furthermore, the HDD 1400 stores programs according to this disclosure, as well as data in storage units 120, 320, and 420. The CPU 1100 reads and executes program data 1450 from the HDD 1400; however, as another example, the program can be obtained from another device via an external network 1550.

[0654] <<8. Other Embodiments>>

[0655] The processing described in the above embodiments can be implemented in various different forms than those described in the above embodiments.

[0656] In the above embodiments, the communication system SYS1 uses the measurement results for switching processing; however, the processing using the measurement results is not limited to switching. For example, in dual connectivity, measurement results for each signal waveform can be used.

[0657] In a dual-connectivity environment, terminal device 50 connects to multiple base stations 20 to perform communication. In this case, the downlink signal waveform can be set for each of the multiple base stations 20 to be connected.

[0658] For example, suppose terminal device 50 is connected to base station 20A and base station 20B via dual connectivity. In this case, terminal device 50 can use a second signal waveform for downlink communication with base station 20A and a first signal waveform for downlink communication with base station 20B.

[0659] Alternatively, terminal device 50 may use the first signal waveform for both downlink communication with base station 20A and downlink communication with base station 20B. Terminal device 50 may also use the second signal waveform for both downlink communication with base station 20A and downlink communication with base station 20B.

[0660] In a dual-connectivity environment, terminal device 50 can obtain information about the signal waveforms (e.g., corresponding to the second waveform information mentioned above) about downlink communication for another base station 20 (e.g., base station 20B) from one base station 20 (e.g., base station 20A).

[0661] For example, terminal device 50 receives downlink signals from another base station 20 based on the acquired second waveform information.

[0662] Furthermore, for example, when terminal device 50 performs communication with a base station 20 using both a first signal waveform and a second signal waveform, communication using a single signal waveform can be switched from one base station 20 to another base station 20.

[0663] For example, suppose terminal device 50 uses both a first signal waveform and a second signal waveform to perform communication with base station 20A. In this case, terminal device 50 can switch downlink communication using the first signal waveform from base station 20A to base station 20B based on the quality of downlink communication using the first signal waveform with base station 20A and / or base station 20B.

[0664] For example, when the quality of downlink communication using the first signal waveform with base station 20A becomes equal to or less than a threshold, base station 20A (or terminal device 50) determines that the downlink communication using the first signal waveform should be switched from base station 20A to base station 20B.

[0665] Alternatively, for example, when the quality of downlink communication using the first signal waveform with base station 20B becomes equal to or greater than a threshold, base station 20A (or terminal device 50) determines that the downlink communication using the first signal waveform should be switched from base station 20A to base station 20B.

[0666] For example, when the quality of downlink communication using the first signal waveform with base station 20A is significantly lower than the quality of downlink communication using the first signal waveform with base station 20B, base station 20A (or terminal device 50) determines to switch from base station 20A to base station 20B.

[0667] Therefore, in the communication system SYS1, the measurement results based on waveform information can be used for various types of processing.

[0668] For example, the control device for controlling the base station 20 and terminal device 50 in the above embodiments can be implemented by a dedicated computer system or by a general-purpose computer system.

[0669] For example, a communication program for performing the above operations is stored on and distributed on a computer-readable recording medium such as an optical disc, semiconductor memory, magnetic tape, or floppy disk. For example, the control device is configured by installing the program in a computer and performing the above processes. In this case, the control device may be a device external to base station 20 and terminal device 50 (e.g., a personal computer). Alternatively, the control device may be a device internal to base station 20 and terminal device 50 (e.g., control units 103 and 203).

[0670] Furthermore, the communication program can be stored on a disk drive included in a server device on a network such as the Internet, and can be downloaded to a computer, for example. Moreover, the above-mentioned functions can be achieved through cooperation between the operating system (OS) and application software. In this case, parts outside the OS can be stored on media and distributed, or parts outside the OS can be stored on a server device and downloaded to a computer, for example.

[0671] Furthermore, all or part of the processes described in the embodiments as automatically executed can also be executed manually, or all or part of the processes described as manually executed can also be executed automatically using known methods. Additionally, unless otherwise stated, the processing procedures, specific names, and information including various data and parameters shown in the above documents and figures can be arbitrarily changed. For example, the various types of information shown in the figures are not limited to the information shown.

[0672] Furthermore, the components of each device shown are conceptual in function and do not necessarily need to be physically configured as shown. That is to say, the specific form of the distribution or integration of the devices is not limited to the form shown, and all or part of them can be functionally or physically distributed or integrated in any unit according to various loads, usage conditions, etc.

[0673] Furthermore, the above embodiments can be appropriately combined as long as the processed content does not contradict each other.

[0674] Furthermore, the effects described in this specification are merely illustrative and not restrictive, and other effects may exist.

[0675] Furthermore, for example, the embodiments can also be implemented as any configuration constituting a device or system, such as a processor for example system-wide integration (LSI), a module using, for example, multiple processors, a unit using, for example, multiple modules, and a collection obtained by further adding other functions to the unit (i.e., a configuration of a part of the device).

[0676] In various embodiments, a system refers to a collection of multiple components (devices, modules (parts), etc.), and it is not important whether all components are housed in the same housing. Therefore, both multiple devices housed in separate housings and connected via a network, and a single device in which multiple modules are housed in one housing, are systems.

[0677] Furthermore, for example, various embodiments may employ a cloud computing configuration in which one of the functions is shared and processed jointly by multiple devices via a network.

[0678] <<9. Conclusion>>

[0679] Although various embodiments of the present disclosure have been described above, the technical scope of the present disclosure is not limited to the above embodiments themselves, and various modifications can be made without departing from the spirit of the present disclosure. Furthermore, components from different embodiments and modifications can be appropriately combined.

[0680] Furthermore, the effects described in the various embodiments in this specification are merely illustrative and not limiting, and other effects may exist.

[0681] This technology can also be configured as follows. (1)

[0683] A base station, comprising: The control unit is configured as follows: Sending first information to the terminal device for measuring the communication quality of downlink communication, the first information including second information about at least one of a first signal waveform and a second signal waveform; and Based on the first information, the terminal device receives a measurement result of the communication quality using a signal having at least one of a first signal waveform and a second signal waveform, wherein... The signal with the first signal waveform is a multi-carrier signal, and the signal with the second signal waveform is a single-carrier signal. (2)

[0685] According to the base station described in (1), the measurement results include the measurement results of the communication quality of the downlink communication of another base station that is different from the base station that has sent the first information. (3)

[0687] According to the base station described in (2), the control unit obtains second information from another base station. (4)

[0689] According to any one of (1) to (3), the base station, wherein the second information includes at least one of the following: information about the validity or invalidity of at least one of the first signal waveform and the second signal waveform; information about the capability of at least one of the first signal waveform and the second signal waveform; and information about the resources of at least one of the first signal waveform and the second signal waveform. (5)

[0691] According to any one of (1) to (4) of the base station, wherein the control unit sends handover information about the handover of the terminal device to the terminal device. (6)

[0693] According to the base station described in (5), the control unit: Determine whether the terminal device needs to perform a handover based on the measurement results; and When it is determined that a handover should be performed, handover information is sent to the terminal device. (7)

[0695] According to the base station described in (5), the control unit sends handover information to the terminal device indicating whether the terminal device should perform a conditional handover. (8)

[0697] According to any one of (5) to (7), the base station, wherein the control unit sends third information to the terminal device regarding at least one of a first signal waveform and a second signal waveform used in downlink communication with the switching destination base station. (9)

[0699] According to the base station described in (8), the third information includes at least one of the following: information about the validity or invalidity of at least one of the first signal waveform and the second signal waveform; information about the capability of at least one of the first signal waveform and the second signal waveform; and information about the resources of at least one of the first signal waveform and the second signal waveform. (10)

[0701] According to the base station described in (8) or (9), the control unit sends third information to the terminal device in the handover information. (11)

[0703] According to any one of (5) to (10), the base station, wherein the control unit sends to the terminal device at least one of a fourth message regarding the measurement of the communication quality of the downlink communication with the handover destination base station and a fifth message regarding the measurement result of the communication quality of the downlink communication with the handover destination base station. (12)

[0705] According to the base station described in (11), the control unit sends at least one of the fourth and fifth information to the terminal device in the handover information. (13)

[0707] According to any one of (1) to (12), the base station, wherein the control unit transmits a first signal having a first signal waveform and used for downlink communication measurement, and a second signal having a second signal waveform and used for downlink communication measurement. (14)

[0709] According to the base station described in (13), the first signal and the second signal are synchronization signal blocks. (15)

[0711] According to the base station described in (13), the first signal and the second signal are reference signals for downlink communication. (16)

[0713] According to the base station described in (15), a common synchronization signal and a broadcast channel are used for the first signal waveform and the second signal waveform. (17)

[0715] According to any one of (1) to (16) of the base station, wherein the control unit receives a report from the terminal device, the report including both the measurement results of the communication quality of downlink communication in the first signal waveform and the measurement results of the communication quality of downlink communication in the second signal waveform. (18)

[0717] According to any one of (1) to (17) of the base station, wherein the control unit performs downlink communication with the terminal device based on the measurement results. (19)

[0719] A terminal device, comprising: The control unit is configured as follows: Receive first information from the base station for measuring the communication quality of downlink communication, the first information including second information about at least one of a first signal waveform and a second signal waveform; The communication quality of downlink communication is measured using a signal having at least one of a first signal waveform and a second signal waveform, based on first information; and The measurement results of downlink communication quality are notified to the base station, among which... The signal with the first signal waveform is a multi-carrier signal, and the signal with the second signal waveform is a single-carrier signal. (20)

[0721] A communication method, comprising: Sending first information to the terminal device for measuring the communication quality of downlink communication, the first information including second information about at least one of a first signal waveform and a second signal waveform; and Based on the first information, the terminal device receives a measurement result of the communication quality using a signal having at least one of a first signal waveform and a second signal waveform, wherein... The signal with the first signal waveform is a multi-carrier signal, and the signal with the second signal waveform is a single-carrier signal. (twenty one)

[0723] A communication method, comprising: Receive first information from the base station for measuring the communication quality of downlink communication, the first information including second information about at least one of a first signal waveform and a second signal waveform; Based on the first information, the communication quality of downlink communication is measured using a signal having at least one of a first signal waveform and a second signal waveform; and The measurement results of downlink communication quality are notified to the base station, among which... The signal with the first signal waveform is a multi-carrier signal, and the signal with the second signal waveform is a single-carrier signal. (twenty two)

[0725] A communication program used to cause a computer to execute: Sending first information to the terminal device for measuring the communication quality of downlink communication, the first information including second information about at least one of a first signal waveform and a second signal waveform; and Based on the first information, the terminal device receives a measurement result of the communication quality using a signal having at least one of a first signal waveform and a second signal waveform, wherein... The signal with the first signal waveform is a multi-carrier signal, and the signal with the second signal waveform is a single-carrier signal. (twenty three)

[0727] A communication program used to cause a computer to execute: Receive first information from the base station for measuring the communication quality of downlink communication, the first information including second information about at least one of a first signal waveform and a second signal waveform; Based on the first information, the communication quality of downlink communication is measured using a signal having at least one of a first signal waveform and a second signal waveform; and The measurement results of downlink communication quality are notified to the base station, among which... The signal with the first signal waveform is a multi-carrier signal, and the signal with the second signal waveform is a single-carrier signal.

[0728] List of reference numerals

[0729] 20 base stations

[0730] 50 terminal devices

[0731] 101, 201 Upper-level processing units

[0732] 103, 203 Control Units

[0733] Receiver units 105 and 205

[0734] Transmitting units 107 and 207

[0735] 109, 209 Transmit / Receive Antennas

[0736] 120 storage units

Claims

1. A base station, comprising: The control unit is configured as follows: Sending first information to the terminal device for measuring the communication quality of downlink communication, the first information including second information about at least one of a first signal waveform and a second signal waveform; as well as Based on the first information, the terminal device receives the communication quality measurement results using a signal having at least one of a first signal waveform and a second signal waveform. Among them, the signal with the first signal waveform is a multi-carrier signal, and the signal with the second signal waveform is a single-carrier signal.

2. The base station according to claim 1, wherein, The measurement results include the results of downlink communication quality measurements from a base station that is different from the base station that has already sent the first information.

3. The base station according to claim 2, wherein, The control unit obtains second information from the other base station.

4. The base station according to claim 1, wherein, The second information includes at least one of the following: information about the validity or invalidity of at least one of the first and second signal waveforms; information about the capability of at least one of the first and second signal waveforms; and information about the resources of at least one of the first and second signal waveforms.

5. The base station according to claim 1, wherein, The control unit sends switching information about the switching of the terminal device to the terminal device.

6. The base station according to claim 5, wherein, Control unit: Determine whether the terminal device needs to perform a handover based on the measurement results; and When it is determined that a handover should be performed, handover information is sent to the terminal device.

7. The base station according to claim 5, wherein, The control unit sends handover information to the terminal device, instructing the terminal device whether to perform a conditional handover.

8. The base station according to claim 5, wherein, The control unit sends third information to the terminal device regarding at least one of a first signal waveform and a second signal waveform used in downlink communication with the handover destination base station.

9. The base station according to claim 5, wherein, The control unit sends at least one of the following to the terminal device: a fourth message regarding the measurement of communication quality with the downlink communication with the handover destination base station, and a fifth message regarding the measurement result of the communication quality with the handover destination base station.

10. The base station according to claim 1, wherein, The control unit sends a first signal having a first signal waveform for measurement of downlink communication, and a second signal having a second signal waveform for measurement of downlink communication.

11. The base station according to claim 10, wherein, The first and second signals are synchronization signal blocks.

12. The base station according to claim 10, wherein, The first and second signals are reference signals for downlink communication.

13. The base station according to claim 12, wherein, A common synchronization signal and a broadcast channel are used for the first signal waveform and the second signal waveform.

14. The base station according to claim 1, wherein, The control unit receives a report from the terminal device, which includes both the measurement results of the communication quality of downlink communication in the first signal waveform and the measurement results of the communication quality of downlink communication in the second signal waveform.

15. The base station according to claim 1, wherein, The control unit performs downlink communication with the terminal device based on the measurement results.

16. A terminal device, comprising: The control unit is configured as follows: Receive first information from the base station for measuring the communication quality of downlink communication, the first information including second information about at least one of a first signal waveform and a second signal waveform; The communication quality of downlink communication is measured using a signal having at least one of a first signal waveform and a second signal waveform, based on the first information. as well as The measurement results of downlink communication quality are notified to the base station, among which... The signal with the first signal waveform is a multi-carrier signal, and the signal with the second signal waveform is a single-carrier signal.

17. A communication method, comprising: Sending first information to the terminal device for measuring the communication quality of downlink communication, the first information including second information about at least one of a first signal waveform and a second signal waveform; as well as Based on the first information, the terminal device receives a measurement result of the communication quality using a signal having at least one of the first signal waveform and the second signal waveform, wherein... The signal with the first signal waveform is a multi-carrier signal, and the signal with the second signal waveform is a single-carrier signal.

18. A communication method, comprising: Receive first information from the base station for measuring the communication quality of downlink communication, the first information including second information about at least one of a first signal waveform and a second signal waveform; Based on the first information, the communication quality of downlink communication is measured using a signal having at least one of a first signal waveform and a second signal waveform; as well as The measurement results of downlink communication quality are notified to the base station, among which... The signal with the first signal waveform is a multi-carrier signal, and the signal with the second signal waveform is a single-carrier signal.

19. A communication program for causing a computer to execute: Sending first information to the terminal device for measuring the communication quality of downlink communication, the first information including second information about at least one of a first signal waveform and a second signal waveform; and Based on the first information, the terminal device receives a measurement result of the communication quality using a signal having at least one of the first signal waveform and the second signal waveform, wherein... The signal with the first signal waveform is a multi-carrier signal, and the signal with the second signal waveform is a single-carrier signal.

20. A communication program for causing a computer to perform: Receive first information from the base station for measuring the communication quality of downlink communication, the first information including second information about at least one of a first signal waveform and a second signal waveform; Based on the first information, the communication quality of downlink communication is measured using a signal having at least one of a first signal waveform and a second signal waveform; as well as The measurement results of downlink communication quality are notified to the base station, among which... The signal with the first signal waveform is a multi-carrier signal, and the signal with the second signal waveform is a single-carrier signal.

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