Wireless communication systems and wireless communication methods
By establishing service links and feeder links between non-terrestrial and terrestrial networks, and implementing site diversity switching in non-terrestrial equipment, the economic feasibility of expanding the service area of the millimeter-wave band was solved, and wider network coverage was achieved.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2022-02-09
- Publication Date
- 2026-03-17
AI Technical Summary
Existing technologies struggle to extend the service area of millimeter-wave bands by combining terrestrial and non-terrestrial networks (NTNs), especially as a more economically viable approach has yet to be established.
By establishing service links and feeder links between non-terrestrial and terrestrial equipment, and implementing site diversity and new feeder link switching in non-terrestrial equipment, the integration of non-terrestrial networks (NTN) and terrestrial networks is achieved.
It expands the service area and improves network coverage, providing more reliable service, especially in areas where terrestrial networks cannot reach.
Smart Images

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Abstract
Description
Technical Field
[0001] The present invention relates to a wireless communication system and a wireless communication method.
Background Art
[0002] In NR (New Radio), which is a successor system to LTE (Long Term Evolution) (also referred to as "5G"), technologies that satisfy requirements such as a large-capacity system, high data transmission speed, low latency, simultaneous connection of a large number of terminals, low cost, and power saving are being studied (for example, Non-Patent Document 1).
[0003] Currently, NTN (Non-Terrestrial Network) is also being studied. NTN uses a non-terrestrial network such as a satellite to provide services to areas that cannot be covered mainly in terms of cost by a terrestrial 5G network (for example, Non-Patent Documents 2 and 3).
Prior Art Documents
Non-Patent Documents
[0004]
Non-Patent Document 1
Non-Patent Document 2
Non-Patent Document 3
Summary of the Invention
Problems to be Solved by the Invention
[0005] It is being considered to expand a broadband area using NTN. For example, especially to improve the area coverage rate of millimeter waves, it is more feasible than to achieve it only with a terrestrial network. A combination of a High Altitude Platform Station (HAPS) system and a terrestrial network may be an economical solution. However, this method had not yet been established.
[0006] This invention has been made in view of the above points, and aims to expand the service area by linking NTN (Non-Terrestrial Network) and the terrestrial network. [Means for solving the problem]
[0007] According to the disclosed technology, a wireless communication system including a non-terrestrial device and a terrestrial device, wherein the non-terrestrial device has a first control unit that establishes a service link with a terminal and a feeder link with the terrestrial device, and a first communication unit that relays between the service link and the feeder link, and the terrestrial device has a second control unit that establishes the feeder link with the non-terrestrial device and a fronthaul with a base station, and a second communication unit that converts the signals of the fronthaul and the signals of the feeder link to each other, and the first control unit of the non-terrestrial device performs site diversity and establishes a new feeder link with another terrestrial device when a deterioration in line quality occurs. If the backhaul line is extended Inter-base station handover If executed and the fronthaul line is extended A wireless communication system is provided that performs handover within the base station. [Effects of the Invention]
[0008] According to the disclosed technology, it is possible to expand the service area by linking NTN (Non-Terrestrial Network) with the terrestrial network. [Brief explanation of the drawing]
[0009] [Figure 1] This diagram shows an example from NTN. [Figure 2] This figure shows an example of a terrestrial network. [Figure 3]It is a diagram showing an example (1) of the NTN system in the embodiment of the present invention. [Figure 4] It is a diagram showing an example (1) of beam operation in the embodiment of the present invention. [Figure 5] It is a diagram showing an example (2) of beam operation in the embodiment of the present invention. [Figure 6] It is a diagram showing an example (1) of frequency operation in the embodiment of the present invention. [Figure 7] It is a diagram showing an example (2) of frequency operation in the embodiment of the present invention. [Figure 8] It is a diagram showing an example (3) of frequency operation in the embodiment of the present invention. [Figure 9] It is a diagram showing an example (2) of the NTN system in the embodiment of the present invention. [Figure 10] It is a diagram showing an example (3) of the NTN system in the embodiment of the present invention. [Figure 11] It is a diagram showing an example (4) of the NTN system in the embodiment of the present invention. [Figure 12] It is a diagram showing an example (5) of the NTN system in the embodiment of the present invention. [Figure 13] It is a diagram showing an example of the functional configuration of the base station 10 in the embodiment of the present invention. [[ID=三十二]] [Figure 14] It is a diagram showing an example of the functional configuration of the terminal 20 in the embodiment of the present invention. [Figure 15] It is a diagram showing an example of the hardware configuration of the base station 10 or the terminal 20 in the embodiment of the present invention. [Figure 16] It is a diagram showing an example of the configuration of the vehicle 2001 in the embodiment of the present invention.
Embodiments for Carrying Out the Invention
[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the embodiments described below are examples, and the embodiments to which the present invention is applied are not limited to the following embodiments.
[0011] It should be noted that there are some inaccuracies in the original Japanese text. For example, "端末20の機能構成の一例を示す図である。" should be "It is a diagram showing an example of the functional configuration of the terminal 20.", and "基地局10又は端末20のハードウェア構成の一例を示す図である。" should be "It is a diagram showing an example of the hardware configuration of the base station 10 or the terminal 20." in the English translation for better grammar and expression. The above translation has been adjusted accordingly. In the operation of the wireless communication system according to the embodiment of the present invention, existing technologies are used as appropriate. However, the existing technology is, for example, existing LTE, but is not limited to existing LTE. In addition, the term "LTE" used in this specification shall have a broad meaning including LTE-Advanced and subsequent systems (e.g., NR) unless otherwise specified.
[0012] In addition, in the embodiments of the present invention described below, terms such as SS (Synchronization signal), PSS (Primary SS), SSS (Secondary SS), PBCH (Physical broadcast channel), PRACH (Physical random access channel), PDCCH (Physical Downlink Control Channel), PDSCH (Physical Downlink Shared Channel), PUCCH (Physical Uplink Control Channel), PUSCH (Physical Uplink Shared Channel), etc. used in existing LTE are used. This is for convenience of description, and signals, functions, etc. similar to these may be called by other names. Also, the above terms in NR correspond to NR-SS, NR-PSS, NR-SSS, NR-PBCH, NR-PRACH, NR-PDCCH, NR-PDSCH, NR-PUCCH, NR-PUSCH, etc. However, even signals used in NR are not necessarily specified as "NR-".
[0013] In addition, in the embodiment of the present invention, the duplex mode may be a TDD (Time Division Duplex) mode, an FDD (Frequency Division Duplex) mode, or another mode (e.g., Flexible Duplex, etc.).
[0014] Furthermore, in the embodiments of the present invention, "configuring" wireless parameters may mean that predetermined values are pre-configured, or that wireless parameters notified from the base station 10 or terminal 20 are configured.
[0015] Figure 1 shows an example of NTN (1). NTN (Non-Terrestrial Network) uses non-terrestrial equipment such as satellites or High Altitude Platform Stations (HAPS) to provide services to areas that could not be covered by terrestrial networks, mainly due to cost constraints. Furthermore, NTN can provide more reliable services. For example, it is envisioned to be applied to IoT (Inter-of-Things), ships, buses, trains, and critical communications. NTN also has scalability through efficient multicast or broadcast.
[0016] As shown in Figure 1, NTN is realized by a satellite in space or an aircraft in the air. For example, a GEO (Geostationary Orbit satellite) may be a satellite located at an altitude of 35,786 km and having a geostationary orbit. For example, a LEO (Low Earth Orbit satellite) may be a satellite located at an altitude of 500-2000 km and orbiting with a period of 88-127 minutes. For example, a HAPS may be an aircraft located at an altitude of 8-50 km and performing a circular flight.
[0017] As shown in Figure 1, GEO satellites, LEO satellites, and HAPS aircraft may provide fixed and mobile services. For example, fixed services may be backhaul to a ground network, etc. For example, mobile services may be provided to terminal 20 directly or via repeaters or relays. The service area may also increase in the order of HAPS, LEO, and GEO.
[0018] NTN can extend network coverage to unserviced or serviced areas, as shown in Figure 1. In particular, when deploying millimeter-wave networks in a wide area, such as achieving 100% area coverage, it may be more economical to achieve this using a combination of NTN and terrestrial networks than to do so with terrestrial networks alone.
[0019] For example, as shown in Figure 1, NTN is envisioned to be used as a disaster countermeasure against earthquakes and typhoons. NTN is also envisioned to be used as a wide-area IoT in mountains, forests, and agricultural lands. Furthermore, NTN is envisioned to provide coverage at sea and in the air. NTN is also envisioned to be used as an industrial network via portable base stations at events or construction sites. Additionally, NTN is envisioned to provide coverage to remote areas through repeaters, relays, and backhaul to base stations. Furthermore, NTN is envisioned to provide high-capacity communication to ships and railways. Finally, NTN is envisioned to provide high-capacity communication to aircraft.
[0020] Figure 2 shows an example of a terrestrial network. As shown in Figure 2, the advanced C-RAN (Centralized Radio Access Network) architecture allows multiple antenna units (RUs: Radio Units) to be extended from a single base station (CU: Centralized Unit / DU: Distributed Unit). Terminals 20 and RUs are connected via 4G or 5G radio in various frequency bands. The RUs are connected to base station 10 via fronthaul. Base station 10 is connected to the core network (CN: Core Network) via backhaul.
[0021] Furthermore, the terrestrial network may have the configuration described below. The terrestrial network includes one or more base stations 10 and terminals 20. The base station 10 is a communication device that provides one or more cells and communicates wirelessly with the terminals 20. The physical resources of the radio signal are defined in the time domain and the frequency domain, the time domain may be defined by the number of OFDM symbols, and the frequency domain may be defined by the number of subcarriers or resource blocks. The base station 10 transmits synchronization signals and system information to the terminals 20. The synchronization signals are, for example, NR-PSS and NR-SSS. The system information is transmitted, for example, in NR-PBCH and is also called broadcast information.
[0022] Base station 10 transmits control signals or data to terminal 20 via DL (Downlink) and receives control signals or data from terminal 20 via UL (Uplink). Both base station 10 and terminal 20 are capable of transmitting and receiving signals using beamforming. Both base station 10 and terminal 20 are also capable of applying MIMO (Multiple Input Multiple Output) communication to DL or UL. Furthermore, both base station 10 and terminal 20 may communicate via SCell (Secondary Cell) and PCell (Primary Cell) using CA (Carrier Aggregation).
[0023] Terminal 20 is a communication device equipped with wireless communication capabilities, such as a smartphone, mobile phone, tablet, wearable device, or M2M (Machine-to-Machine) communication module. Terminal 20 receives control signals or data from base station 10 via DL and transmits control signals or data to base station 10 via UL, thereby utilizing various communication services provided by the wireless communication system.
[0024] In this context, it is desirable to utilize existing 4G or 5G terrestrial networks as much as possible in HAPS systems. For example, the utilization of the core network and fronthaul in the HAPS system may be considered. In particular, in non-regenerative (transparent) systems that do not have base stations 10 installed in the HAPS, it is assumed that the terrestrial network can be effectively utilized.
[0025] Figure 3 shows an example (1) of an NTN system in an embodiment of the present invention. Figure 3 shows an example of a system configuration of a direct access (DA) and a transparent architecture. As shown in Figure 3, the NTN system in an embodiment of the present invention may have a HAPS ground system and a HAPS relay system. The fronthaul from the core network utilizes the ground network. For base station 10, the installation configuration of the CU / DU may be integrated or protruding.
[0026] The HAPS ground system includes a RU (Radio Frequency Response) function that converts signals from the fronthaul optical line to analog OFDM signals. The HAPS ground system may also transmit and receive signals from N beams of service links (SL) bundled together via a feeder link (FL). The feeder link may, for example, utilize the Q band (33 GHz to 50 GHz) or be configured with a bandwidth of 20 MHz × N.
[0027] The HAPS relay system relays service links and feeder links. The relay system may employ a bent pipe system for frequency conversion and power amplification. The service links may be transmitted and received simultaneously with N beams, and may be 4G or 5G wireless, or may support 6G wireless in the future. The service links may, for example, utilize the S-band (2GHz to 4GHz), and the bandwidth of one service link may be 20MHz.
[0028] Figure 4 shows an example of beam operation (1) in an embodiment of the present invention. As shown in Figure 4, the HAPS relay system 10A may associate multiple beams with each cell. Each cell may correspond to one PCI. Each synchronous signal block (SSB) may be configured as a beam. By associating multiple beams with each cell, Layer 1 beam switching becomes possible, and delay can be reduced.
[0029] Figure 5 shows an example (2) of beam operation in an embodiment of the present invention. As shown in Figure 5, the HAPS relay system 10A may associate one beam with each cell. One cell may correspond to one PCI. By associating one beam with each cell, beams can be switched by handover.
[0030] Regarding beam operation, the example shown in Figure 4 or the example shown in Figure 5 may be adopted.
[0031] Figure 6 shows an example (1) of frequency operation in an embodiment of the present invention. As shown in Figure 6, frequency F0 may be reused for each beam. Note that one region shown in Figure 6 may correspond to one beam or one cell.
[0032] Figure 7 shows an example (2) of frequency operation in an embodiment of the present invention. Frequencies F0, F1, and F2 may be used and the frequencies may be reused in the arrangement shown in Figure 7. Note that one region shown in Figure 7 may correspond to one beam or one cell.
[0033] Figure 8 shows an example (3) of frequency operation in an embodiment of the present invention. Frequencies F0, F1, and F2 are used, and the RHCP (Right-hand circularly polarized) and LHCP (Left-hand circularly polarized) of each frequency may be used to reuse the frequencies in the arrangement shown in Figure 8. Note that one region shown in Figure 8 may correspond to one beam or one cell.
[0034] Regarding frequency reuse, the example shown in Figure 6, the example shown in Figure 7, or the example shown in Figure 8 may be adopted.
[0035] Figure 9 shows an example (2) of an NTN system in an embodiment of the present invention. As shown in Figure 9, the service link connecting to the HAPS relay system may be transmitted and received via a relay station (or booster, attachment, etc.) instead of being transmitted and received directly by the UE. Also as shown in Figure 9, communication via a relay station can coexist with direct access and may complement situations where the required performance cannot be achieved with direct access (e.g., long distances, indoor environments, congested areas, etc.). When the service link is increased in frequency, communication via a relay station is expected to be very effective.
[0036] Figure 10 shows an example (3) of an NTN system in an embodiment of the present invention. As shown in Figure 10, the configuration may be modeled after a satellite CBH (Cellular Backhaul) system. That is, the HAPS system may support backhaul between the core network and base stations as an independent tunnel circuit. Also, as shown in Figure 10, the HAPS relay system may support regenerative relay by equipping it with communication equipment, in addition to the vented pipe method.
[0037] As shown in Figure 10, the service link may, for example, transmit and receive simultaneously with M beams, utilize the Q band, and have a bandwidth of 100 MHz. The UE may connect to the RU via 4G or 5G radio and further communicate with the HAPS relay system via base stations (CU / DU) and CPE (Customer Premises Equipment). The feeder link may, for example, utilize the Q band, or be configured with a bandwidth of 100 MHz × M.
[0038] Compared to the direct-access CBH-like architecture shown in Figure 9, the architecture shown in Figure 10 can achieve high speed and large capacity exceeding several hundred Mbps by applying high-frequency bands such as the Q-band to the service link. Furthermore, it allows for relatively free operation of 4G or 5G wireless frequency bands. On the other hand, compared to the direct-access CBH-like architecture shown in Figure 9, the architecture shown in Figure 10 requires additional system configurations beyond those of direct access.
[0039] Figure 11 shows an example (4) of an NTN system in an embodiment of the present invention. As shown in Figure 11, a single HAPS relay system can support both direct access and high-speed, high-capacity CBH, enabling various use cases simultaneously. This allows for efficient utilization of the HAPS relay system's equipment and wireless resources. For example, even when CBH is not in use, it can be utilized as direct access, avoiding situations where the HAPS relay system is operational but unused. Furthermore, as shown in Figure 10, the HAPS relay system may support regenerative relay by incorporating communication equipment in addition to the vented pipe method, or it may support a hybrid type incorporating both the vented pipe method and communication equipment.
[0040] Furthermore, as shown in Figure 11, the service link can be multibanded for direct access (e.g., S-band) and CBH (e.g., Q-band). As shown in Figure 11, the DA service link may transmit and receive simultaneously with, for example, M beams, utilize the S-band, and have a bandwidth of 20 MHz per service link. As shown in Figure 11, the CBH service link may transmit and receive simultaneously with, for example, N beams, utilize the Q-band, and have a bandwidth of 100 MHz per service link. The feeder link may utilize the Q-band, for example, and may be configured with bandwidths of 20 MHz × N and 100 MHz × M. Furthermore, as shown in Figure 10, the HAPS relay system may support regenerative relay by incorporating communication equipment, in addition to the vented pipe method.
[0041] Furthermore, as shown in Figure 11, the HAPS ground system may be multiband compatible to accommodate both DA and CBH, and may utilize the ground network by supporting fronthaul to base stations (CU / DU) and backhaul to the core network.
[0042] Figure 12 shows an example (5) of an NTN system in an embodiment of the present invention. As shown in Figure 12, in particular in a non-regenerative relay system, the handover control when route switching (site diversity) occurs due to rainfall, etc., may be a handover control that is similar to the site diversity method of the feeder link.
[0043] As shown in Figure 12, if the line quality deteriorates due to rain, snow, etc., the HAPS relay system may perform site diversity by switching the connection destination. Regarding feeder links, when site diversity occurs, a new feeder link may be connected, or two or more feeder links may be connected in advance. Alternatively, when site diversity occurs, the feeder link may be configured to pass through another HAPS relay system using inter-HAPS communication.
[0044] If the HAPS ground system receiving the handover is, for example, several tens of kilometers away from the HAPS ground system receiving the handover, the backhaul link may be extended, and an X2 handover or S1 handover between base stations may be performed.
[0045] If the HAPS ground system to be handed over to is located, for example, within several tens of kilometers of the HAPS ground system from which the handover originated, the fronthaul link may be extended using a common base station, and an intra-base station handover may be performed.
[0046] The trigger for site diversity, which switches the connection destination as described above, may be, for example, a measurement report from the UE, a reference signal (CSI-RS (Channel State Information - Reference Signal)) from the HAPS ground system, or a rainfall prediction algorithm.
[0047] As demonstrated in the above-described embodiment, the HAPS relay system and HAPS terrestrial system can be introduced in the NTN environment, enabling the use of the terrestrial network from the core network to the fronthaul. Furthermore, the HAPS relay system can support both direct access and CBH.
[0048] In other words, by linking NTN (Non-Terrestrial Network) with the terrestrial network, the service area can be expanded.
[0049] (Device configuration) Next, an example of the functional configuration of the base station 10 and terminal 20 that perform the processes and operations described above will be explained. The base station 10 and terminal 20 include functions to implement the embodiments described above. However, the base station 10 and terminal 20 may each have only some of the functions in the embodiments. Note that devices included in non-terrestrial networks and devices included in terrestrial networks may have the same functional configuration as the base station 10.
[0050] <Base station 10> Figure 13 shows an example of the functional configuration of a base station 10 in an embodiment of the present invention. As shown in Figure 13, the base station 10 has a transmitting unit 110, a receiving unit 120, a setting unit 130, and a control unit 140. The functional configuration shown in Figure 13 is merely an example. The names of the functional categories and functional units can be anything as long as they can perform the operations according to the embodiment of the present invention.
[0051] The transmitting unit 110 includes the function of generating a signal to be transmitted to the terminal 20 and transmitting the signal wirelessly. The transmitting unit 110 also transmits inter-network node messages to other network nodes. The receiving unit 120 includes the function of receiving various signals transmitted from the terminal 20 and obtaining information from the received signals, for example, higher layer information. The transmitting unit 110 also has the function of transmitting NR-PSS, NR-SSS, NR-PBCH, DL / UL control signals, etc. to the terminal 20. The receiving unit 120 also receives inter-network node messages from other network nodes.
[0052] The configuration unit 130 stores pre-configured configuration information and various configuration information to be transmitted to the terminal 20. The contents of the configuration information include, for example, information related to communication at NTN.
[0053] As described in the embodiment, the control unit 140 performs control related to communication in NTN. The control unit 140 also controls communication with terminal 20 based on the UE capability report regarding wireless parameters received from terminal 20. The signal transmission function of the control unit 140 may be included in the transmission unit 110, and the signal reception function of the control unit 140 may be included in the reception unit 120.
[0054] <Terminal 20> Figure 14 is a diagram showing an example of the functional configuration of terminal 20 in an embodiment of the present invention. As shown in Figure 14, terminal 20 has a transmitting unit 210, a receiving unit 220, a setting unit 230, and a control unit 240. The functional configuration shown in Figure 14 is merely an example. Any functional classification and functional unit names are acceptable as long as they can perform the operations according to the embodiment of the present invention.
[0055] The transmitting unit 210 creates a transmission signal from the transmission data and transmits the transmission signal wirelessly. The receiving unit 220 wirelessly receives various signals and acquires signals from higher layers from the received physical layer signals. The receiving unit 220 also has the function of receiving NR-PSS, NR-SSS, NR-PBCH, DL / UL / SL control signals, etc. transmitted from the base station 10. For example, the transmitting unit 210 transmits PSCCH (Physical Sidelink Control Channel), PSSCH (Physical Sidelink Shared Channel), PSDCH (Physical Sidelink Discovery Channel), PSBCH (Physical Sidelink Broadcast Channel), etc. to other terminals 20 as D2D communication, and the receiving unit 120 receives PSCCH, PSSCH, PSDCH or PSBCH, etc. from other terminals 20.
[0056] The setting unit 230 stores various setting information received from the base station 10 by the receiving unit 220. The setting unit 230 also stores pre-configured setting information. The content of the setting information includes, for example, information related to NTN communications.
[0057] The control unit 240 performs control related to communication in NTN, as described in the embodiment. The signal transmission function of the control unit 240 may be included in the transmission unit 210, and the signal reception function of the control unit 240 may be included in the reception unit 220.
[0058] (Hardware configuration) The block diagrams (Figures 13 and 14) used in the description of the above embodiments show functional units. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method of realizing each functional block is not particularly limited. That is, each functional block may be realized using one device that is physically or logically coupled, or it may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wired or wireless connections). A functional block may be realized by combining the one or more devices with software.
[0059] Functions include, but are not limited to, judgment, decision, judgment, calculation, calculation, processing, derivation, investigation, exploration, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, assumption, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating (mapping), and assigning. For example, a functional block (configuration part) that enables transmission is called a transmitting unit or transmitter. As mentioned above, the method of implementation is not particularly limited.
[0060] For example, each device in the non-terrestrial network, each device in the terrestrial network, and terminal 20 in one embodiment of the present disclosure may function as a computer that processes the wireless communication method of the present disclosure. Figure 15 is a diagram showing an example of the hardware configuration of each device in the non-terrestrial network, each device in the terrestrial network, and terminal 20 according to the embodiment. The above-mentioned each device in the non-terrestrial network, each device in the terrestrial network, and terminal 20 may be physically configured as a computer device including a processor 1001, a storage device 1002, an auxiliary storage device 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.
[0061] In the following explanation, the term "device" can be replaced with "circuit," "device," "unit," etc. The hardware configuration of the base station 10, terminal 20, each device of the non-terrestrial network, and each device of the terrestrial network may be configured to include one or more of the devices shown in the diagram, or it may be configured to omit some of the devices.
[0062] Each function in the base station 10, terminal 20, non-terrestrial network equipment, and terrestrial network equipment is realized by loading predetermined software (programs) onto hardware such as the processor 1001 and storage device 1002, which allows the processor 1001 to perform calculations, control communication by the communication device 1004, and control at least one of the reading and writing of data in the storage device 1002 and auxiliary storage device 1003.
[0063] The processor 1001 controls the entire computer, for example, by running an operating system. The processor 1001 may consist of a central processing unit (CPU) that includes interfaces with peripheral devices, control devices, arithmetic units, registers, etc. For example, the control unit 140, control unit 240, etc., described above may be implemented by the processor 1001.
[0064] Furthermore, the processor 1001 reads programs (program code), software modules, or data from at least one of the auxiliary storage device 1003 and the communication device 1004 into the storage device 1002, and executes various processes accordingly. The program used is one that causes a computer to execute at least a part of the operations described in the above embodiment. For example, the control unit 140 of the base station 10 shown in Figure 13 may be implemented by a control program stored in the storage device 1002 and operated by the processor 1001. Also, for example, the control unit 240 of the terminal 20 shown in Figure 14 may be implemented by a control program stored in the storage device 1002 and operated by the processor 1001. Although the above-described processes have been explained as being executed by one processor 1001, they may be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The program may be transmitted from the network via a telecommunications line.
[0065] The storage device 1002 is a computer-readable recording medium and may consist of at least one of the following: ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable ROM), RAM (Random Access Memory), etc. The storage device 1002 may also be called a register, cache, main memory, etc. The storage device 1002 can store executable programs (program code), software modules, etc., for implementing a communication method according to one embodiment of this disclosure.
[0066] The auxiliary storage device 1003 is a computer-readable recording medium and may consist of at least one of the following: an optical disc such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disc, a digital multipurpose disc, a Blu-ray® disc), a smart card, flash memory (e.g., a card, a stick, a key drive), a floppy® disk, a magnetic strip, etc. The above-mentioned storage medium may also be a database, server, or other suitable medium that includes at least one of the storage device 1002 and the auxiliary storage device 1003.
[0067] The communication device 1004 is hardware (transceiver / receiver device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as a network device, network controller, network card, communication module, etc. The communication device 1004 may include high-frequency switches, duplexers, filters, frequency synthesizers, etc., to implement at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, the transmit / receive antenna, amplifier section, transmit / receive section, transmission path interface, etc., may be implemented by the communication device 1004. The transmit / receive section may be implemented with physically or logically separated transmitting and receiving sections.
[0068] The input device 1005 is an input device that accepts input from an external source (e.g., a keyboard, mouse, microphone, switch, button, sensor, etc.). The output device 1006 is an output device that outputs to an external source (e.g., a display, speaker, LED lamp, etc.). The input device 1005 and the output device 1006 may be configured as an integrated unit (e.g., a touch panel).
[0069] Furthermore, each device, such as the processor 1001 and the storage device 1002, is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or different buses may be configured for each device.
[0070] Furthermore, the base station 10 and terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), and an FPGA (Field Programmable Gate Array), and some or all of each functional block may be realized by such hardware. For example, the processor 1001 may be implemented using at least one of these hardware components.
[0071] Figure 16 shows an example of the configuration of vehicle 2001. As shown in Figure 16, vehicle 2001 comprises a drive unit 2002, a steering unit 2003, an accelerator pedal 2004, a brake pedal 2005, a shift lever 2006, front wheels 2007, rear wheels 2008, an axle 2009, an electronic control unit 2010, various sensors 2021 to 2029, an information service unit 2012, and a communication module 2013. Each aspect / embodiment described in this disclosure may be applied to a communication device mounted on vehicle 2001, for example, to the communication module 2013.
[0072] The drive unit 2002 consists of, for example, an engine, a motor, or a hybrid of an engine and a motor. The steering unit 2003 includes at least a steering wheel (also called a handle) and is configured to steer at least one of the front wheels and the rear wheels based on the operation of the steering wheel, which is operated by the user.
[0073] The electronic control unit 2010 consists of a microprocessor 2031, memory (ROM, RAM) 2032, and communication ports (IO ports) 2033. Signals from various sensors 2021 to 2029 installed in the vehicle 2001 are input to the electronic control unit 2010. The electronic control unit 2010 may also be called an ECU (Electronic Control Unit).
[0074] Signals from various sensors 2021-2029 include current signals from current sensor 2021 which senses motor current, front and rear wheel rotation speed signals obtained by rotation speed sensor 2022, front and rear wheel air pressure signals obtained by air pressure sensor 2023, vehicle speed signals obtained by vehicle speed sensor 2024, acceleration signals obtained by acceleration sensor 2025, accelerator pedal depression signals obtained by accelerator pedal sensor 2029, brake pedal depression signals obtained by brake pedal sensor 2026, shift lever operation signals obtained by shift lever sensor 2027, and detection signals obtained by object detection sensor 2028 for detecting obstacles, vehicles, pedestrians, etc.
[0075] The Information Services Unit 2012 consists of various devices for providing various types of information, such as driving information, traffic information, and entertainment information, including a car navigation system, audio system, speakers, television, and radio, and one or more ECUs that control these devices. The Information Services Unit 2012 uses information acquired from external devices via a communication module 2013, etc., to provide various multimedia information and multimedia services to the occupants of the vehicle 2001.
[0076] The driver assistance system unit 2030 consists of various devices that provide functions to prevent accidents or reduce the driver's workload, such as millimeter-wave radar, LiDAR (Light Detection and Ranging), cameras, positioning locators (e.g., GNSS), map information (e.g., high-definition (HD) maps, autonomous vehicle (AV) maps, etc.), gyro systems (e.g., IMU (Inertial Measurement Unit), INS (Inertial Navigation System), etc.), AI (Artificial Intelligence) chips, and AI processors, as well as one or more ECUs that control these devices. The driver assistance system unit 2030 also sends and receives various information via the communication module 2013 to realize driver assistance functions or autonomous driving functions.
[0077] The communication module 2013 can communicate with the microprocessor 2031 and components of the vehicle 2001 via its communication port. For example, the communication module 2013 sends and receives data via its communication port 2033 to the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axle 2009, the microprocessor 2031 and memory (ROM, RAM) 2032 in the electronic control unit 2010, and sensors 2021-29 provided in the vehicle 2001.
[0078] The communication module 2013 is a communication device that can be controlled by the microprocessor 2031 of the electronic control unit 2010 and can communicate with external devices. For example, it can send and receive various types of information to and from external devices via wireless communication. The communication module 2013 may be located either inside or outside the electronic control unit 2010. The external device may be, for example, a base station or a mobile station.
[0079] The communication module 2013 transmits current signals from current sensors input to the electronic control unit 2010 to an external device via wireless communication. The communication module 2013 also transmits, via wireless communication, other signals input to the electronic control unit 2010, including front and rear wheel rotation speed signals obtained by the rotation speed sensor 2022, front and rear wheel air pressure signals obtained by the air pressure sensor 2023, vehicle speed signals obtained by the vehicle speed sensor 2024, acceleration signals obtained by the acceleration sensor 2025, accelerator pedal depression signals obtained by the accelerator pedal sensor 2029, brake pedal depression signals obtained by the brake pedal sensor 2026, shift lever operation signals obtained by the shift lever sensor 2027, and detection signals obtained by the object detection sensor 2028 for detecting obstacles, vehicles, pedestrians, etc.
[0080] The communication module 2013 receives various information (traffic information, signal information, distance information, etc.) transmitted from an external device and displays it on the information service unit 2012 installed in the vehicle 2001. The communication module 2013 also stores the various information received from the external device in memory 2032, which is available to the microprocessor 2031. Based on the information stored in memory 2032, the microprocessor 2031 may control the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axles 2009, sensors 2021-2029, etc., installed in the vehicle 2001.
[0081] (Summary of the embodiments) As described above, according to embodiments of the present invention, a wireless communication system is provided which includes a non-terrestrial device and a terrestrial device, wherein the non-terrestrial device has a first control unit that establishes a service link with a terminal and a feeder link with the terrestrial device, and a first communication unit that relays between the service link and the feeder link, and the terrestrial device has a second control unit that establishes the feeder link with the non-terrestrial device and a fronthaul with a base station, and a second communication unit that converts the signals of the fronthaul and the signals of the feeder link to each other.
[0082] With the above configuration, the HAPS relay system and HAPS terrestrial system can be introduced in the NTN environment, enabling the use of the terrestrial network from the core network to the fronthaul. Furthermore, the HAPS relay system can support both direct access and CBH. In other words, the service area can be expanded by linking NTN (Non-Terrestrial Network) and the terrestrial network.
[0083] The service links are direct access, and the first control unit may establish a plurality of the service links in a first band and a feeder link in a second band, the first communication unit may apply beams to each of the plurality of service links and transmit and receive simultaneously, the second control unit may establish the feeder link in a second band, and the second communication unit may bundle and transmit and receive signals corresponding to the plurality of service links. With this configuration, in the NTN environment, a HAPS relay system and a HAPS ground system can be introduced and the ground network can be utilized from the core network to the front haul.
[0084] The service link is configured as a CBH (Cellular Backhaul), the first control unit establishes a plurality of the service links in the second band, and the feeder link in the second band, the first communication unit applies beams to each of the plurality of service links and transmits and receives simultaneously, the second control unit establishes the feeder link in the second band, and the second communication unit bundles and transmits and receives signals corresponding to the plurality of service links. With this configuration, in the NTN environment, a HAPS relay system and a HAPS ground system can be introduced, and the ground network can be utilized from the core network to the fronthaul.
[0085] The service links are configured as direct access and CBH, the first control unit establishes a first plurality of the service links in the first band, a second plurality of the service links in the second band, and a feeder link in the second band, the first communication unit applies beams to each of the first plurality of the service links and transmits and receives simultaneously, applies beams to each of the second plurality of the service links and transmits and receives simultaneously, the second control unit establishes the feeder link in the second band, and the second communication unit may bundle and transmit and receive signals corresponding to the first plurality of the service links and signals corresponding to the second plurality of the service links. With this configuration, in an NTN environment, a HAPS relay system and a HAPS ground system can be introduced and the ground network can be utilized from the core network to the fronthaul. Furthermore, the HAPS relay system can support both direct access and CBH.
[0086] If the quality of the feeder link deteriorates, the first control unit may switch the ground device that establishes the feeder link to another ground device and establish a new feeder link, or it may use a feeder link that has been previously established with the other ground device. With this configuration, a HAPS relay system and a HAPS ground system can be introduced in the NTN environment, and site diversity can be implemented.
[0087] Furthermore, according to embodiments of the present invention, a wireless communication method is provided for a wireless communication system including a non-terrestrial device and a terrestrial device, wherein the non-terrestrial device performs a first control procedure to establish a service link with a terminal and a feeder link with the terrestrial device, and a first communication procedure to relay between the service link and the feeder link, and the terrestrial device performs a second control procedure to establish the feeder link with the non-terrestrial device and a fronthaul with a base station, and a second communication procedure to convert the fronthaul signal and the feeder link signal to each other.
[0088] With the above configuration, the HAPS relay system and HAPS terrestrial system can be introduced in the NTN environment, enabling the use of the terrestrial network from the core network to the fronthaul. Furthermore, the HAPS relay system can support both direct access and CBH. In other words, the service area can be expanded by linking NTN (Non-Terrestrial Network) and the terrestrial network.
[0089] (Supplement to the embodiment) While embodiments of the present invention have been described above, the disclosed invention is not limited to such embodiments, and those skilled in the art will understand various modifications, alterations, alternatives, substitutions, etc. Specific numerical examples have been used to facilitate understanding of the invention, but unless otherwise specified, these numerical values are merely examples, and any appropriate values may be used. The division of items in the above description is not essential to the present invention, and matters described in two or more items may be combined as needed, and matters described in one item may be applied to matters described in another item (as long as they do not contradict each other). The boundaries of functional units or processing units in the functional block diagram do not necessarily correspond to the boundaries of physical parts. The operation of multiple functional units may be physically performed by one part, or the operation of one functional unit may be physically performed by multiple parts. Regarding the processing procedures described in the embodiments, the order of processing may be changed as long as it does not contradict each other. For the convenience of explaining the processing, the base station 10 and terminal 20 have been described using functional block diagrams, but such devices may be implemented in hardware, software, or a combination thereof. The software operated by the processor of the base station 10 according to an embodiment of the present invention and the software operated by the processor of the terminal 20 according to an embodiment of the present invention may be stored in random access memory (RAM), flash memory, read-only memory (ROM), EPROM, EEPROM, registers, hard disk (HDD), removable disk, CD-ROM, database, server, or any other suitable storage medium.
[0090] Furthermore, the notification of information is not limited to the embodiments / models described herein and may be carried out by other methods. For example, the notification of information may be carried out by physical layer signaling (e.g., DCI (Downlink Control Information), UCI (Uplink Control Information)), upper layer signaling (e.g., RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling), broadcast information (MIB (Master Information Block), SIB (System Information Block)), other signals, or combinations thereof. Also, RRC signaling may be called RRC messages, and may be, for example, RRC Connection Setup messages, RRC Connection Reconfiguration messages, etc.
[0091] Each aspect / embodiment described in this disclosure includes LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), 6th generation mobile communication system (6G), xth generation mobile communication system (xG) (xG (where x is, for example, an integer or decimal)), FRA (Future Radio Access), NR (new Radio), New radio access (NX), Future generation radio access (FX), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), and IEEE This may apply to at least one system utilizing 802.20, UWB (Ultra-WideBand), Bluetooth®, or other appropriate systems, and to next-generation systems extended, modified, created, or defined based thereon. It may also apply to a combination of multiple systems (for example, a combination of at least one of LTE and LTE-A with 5G).
[0092] The processing procedures, sequences, flowcharts, etc., of each aspect / embodiment described herein may be reordered, provided they are consistent with each other. For example, the methods described herein present various step elements in an exemplary order and are not limited to that specific order.
[0093] In this specification, specific operations performed by the base station 10 may, in some cases, be performed by its upper node. In a network consisting of one or more network nodes having a base station 10, it is clear that various operations performed for communication with the terminal 20 can be performed by the base station 10 and at least one of the other network nodes (for example, an MME or S-GW, but not limited to these). Although the above example illustrates the case where there is one other network node besides the base station 10, the other network node may be a combination of multiple other network nodes (for example, an MME and an S-GW).
[0094] The information or signals described in this disclosure may be output from a higher layer (or lower layer) to a lower layer (or higher layer). They may also be input and output via multiple network nodes.
[0095] Input and output information may be stored in a specific location (e.g., memory) or managed using a management table. Input and output information may be overwritten, updated, or appended to. Output information may be deleted. Input information may be transmitted to other devices.
[0096] The determination in this disclosure may be made by a value represented by one bit (0 or 1), by a boolean value (true or false), or by a numerical comparison (for example, a comparison with a predetermined value).
[0097] Software should be broadly interpreted to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, procedures, functions, and so on, whether they are called software, firmware, middleware, microcode, hardware description languages, or by any other name.
[0098] Furthermore, software, instructions, information, etc., may be transmitted and received via a transmission medium. For example, if software is transmitted from a website, server, or other remote source using at least one of wired technology (such as coaxial cable, fiber optic cable, twisted pair, or digital subscriber line (DSL)) and wireless technology (such as infrared or microwave), then at least one of these wired and wireless technologies is included in the definition of a transmission medium.
[0099] The information, signals, etc. described in this disclosure may be represented using any of the various different techniques. For example, the data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.
[0100] In addition, terms used in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, at least one of the channel and symbol may be a signal (signaling). Also, a signal may be a message. Furthermore, a component carrier (CC) may be called a carrier frequency, cell, frequency carrier, etc.
[0101] The terms “system” and “network” as used in this disclosure are interchangeable.
[0102] Furthermore, the information, parameters, etc., described in this disclosure may be expressed using absolute values, relative values from a given value, or other corresponding information. For example, wireless resources may be indicated by an index.
[0103] The names used for the parameters described above are not restrictive in any way. Furthermore, the formulas and other expressions using these parameters may differ from those expressly disclosed in this disclosure. Various channels (e.g., PUCCH, PDCCH, etc.) and information elements can be identified by any suitable name, and therefore, the various names assigned to these various channels and information elements are not restrictive in any way.
[0104] In this disclosure, terms such as "base station (BS)", "wireless base station", "base station equipment", "fixed station", "NodeB", "eNodeB (eNB)", "gNodeB (gNB)", "access point", "transmission point", "reception point", "transmission / reception point", "cell", "sector", "cell group", "carrier", and "component carrier" may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, and picocell.
[0105] A base station can house one or more (e.g., three) cells. If a base station houses multiple cells, the entire coverage area of the base station can be divided into several smaller areas, each of which may also be provided with communication services by a base station subsystem (e.g., a Remote Radio Head (RRH)). The terms “cell” or “sector” refer to part or all of the coverage area of at least one of the base station and / or base station subsystems that provide communication services in that coverage.
[0106] In this disclosure, terms such as "Mobile Station (MS)," "user terminal," "User Equipment (UE)," and "terminal" may be used interchangeably.
[0107] A mobile station may also be referred to by those skilled in the art as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or several other appropriate terms.
[0108] At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a communication device, etc. At least one of the base station and the mobile station may be a device mounted on a mobile body, the mobile body itself, etc. The mobile body may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile body (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may be a device that does not necessarily move during communication operation. For example, at least one of the base station and the mobile station may be an IoT (Internet of Things) device such as a sensor.
[0109] Furthermore, the term "base station" in this disclosure may be interpreted as "user terminal." For example, the various aspects / embodiments of this disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between multiple terminals 20 (which may be called, for example, D2D (Device-to-Device), V2X (Vehicle-to-Everything), etc.). In this case, the terminals 20 may have the functions that the base station 10 has. Also, terms such as "uplink" and "downlink" may be interpreted as terms corresponding to terminal-to-terminal communication (for example, "side"). For example, uplink channel, downlink channel, etc., may be interpreted as side channel.
[0110] Similarly, the term "user terminal" in this disclosure may be replaced with "base station." In this case, the base station may be configured to have the same functions as the user terminal described above.
[0111] As used in this disclosure, the terms “determining” and “determining” may encompass a wide variety of actions. “Determining” may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiry (e.g., searching in a table, database, or other data structure), and ascertaining. “Determining” may also include, for example, receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, and accessing (e.g., accessing data in memory). Furthermore, "judgment" and "decision" can include considering something as having been "judged" or "decided" after resolving, selecting, choosing, establishing, comparing, etc. In other words, "judgment" and "decision" can include considering something as having been "judged" or "decided" after some action. Also, "judgment (decision)" can be reinterpreted as "assuming," "expecting," or "considering."
[0112] The terms “connected,” “coupled,” or any variation thereof, mean any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are “connected” or “coupled” with each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, “connection” may be reinterpreted as “access.” As used in this disclosure, two elements may be considered to be “connected” or “coupled” with each other using at least one of one or more wires, cables, and printed electrical connections, and, in some non-limiting and non-exclusive examples, electromagnetic energy having wavelengths in the radio frequency domain, microwave domain, and optical (both visible and invisible) domain.
[0113] The reference signal can also be abbreviated as RS (Reference Signal), and may be called a pilot depending on the applicable standard.
[0114] In this disclosure, the phrase "based on" does not mean "based solely on" unless otherwise specified. In other words, the phrase "based on" means both "based solely on" and "based at least on."
[0115] Any reference to elements using the designations “first,” “second,” etc., as used in this disclosure does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient way to distinguish between two or more elements. Accordingly, references to the first and second elements do not imply that only two elements may be employed, or that the first element must precede the second element in any way.
[0116] In the configuration of each of the above devices, "means" may be replaced with "part," "circuit," "device," etc.
[0117] Where the terms “include,” “including,” and variations thereof are used in this disclosure, these terms are intended to be inclusive, as is the term “comprising.” Furthermore, the term “or” as used in this disclosure is not intended to mean exclusive OR.
[0118] A wireless frame may consist of one or more frames in the time domain. Each of these frames in the time domain may be called a subframe. A subframe may further consist of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.
[0119] Numerical logic may be communication parameters applied to at least one of the transmission and reception of a signal or channel. Numerical logic may include, for example, at least one of the following: subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame configuration, specific filtering processes performed by the transceiver in the frequency domain, and specific windowing processes performed by the transceiver in the time domain.
[0120] A slot may consist of one or more symbols in the time domain (such as OFDM (Orthogonal Frequency Division Multiplexing) symbols, SC-FDMA (Single Carrier Frequency Division Multiple Access) symbols, etc.). A slot may also be a time unit based on neurology.
[0121] A slot may include multiple minislots. Each minislot may consist of one or more symbols in the time domain. Minislots may also be called subslots. Minislots may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (or PUSCH) mapping type B.
[0122] Wireless frames, subframes, slots, minislots, and symbols all represent units of time when transmitting a signal. Different names may be used for each of these terms.
[0123] For example, one subframe may be called a Transmission Time Interval (TTI), multiple consecutive subframes may be called a TTI, or one slot or one mini-slot may be called a TTI. In other words, at least one of a subframe and a TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (e.g., 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, mini-slot, etc., instead of a subframe.
[0124] Here, TTI refers to, for example, the smallest unit of time for scheduling in wireless communication. For example, in an LTE system, the base station schedules each terminal 20 to allocate wireless resources (such as the frequency bandwidth and transmission power available to each terminal 20) in TTI units. However, the definition of TTI is not limited to this.
[0125] TTI may be a transmission time unit for channel-encoded data packets (transport blocks), code blocks, code words, etc., or it may be a processing unit for scheduling, link adaptation, etc. Given a TTI, the actual time interval (e.g., number of symbols) to which the transport block, code block, code word, etc. are mapped may be shorter than the given TTI.
[0126] Furthermore, if one slot or one mini-slot is referred to as TTI, then one or more TTIs (i.e., one or more slots or one or more mini-slots) may constitute the minimum time unit of scheduling. In addition, the number of slots (number of mini-slots) that constitute the minimum time unit of scheduling may be controlled.
[0127] A TTI with a time length of 1ms may also be called a normal TTI, long TTI, normal subframe, long subframe, slot, etc. A TTI shorter than a normal TTI may also be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, mini slot, sub slot, slot, etc.
[0128] Furthermore, long TTIs (e.g., normal TTIs, subframes, etc.) may be interpreted as TTIs with a time length exceeding 1 ms, and short TTIs (e.g., shortened TTIs, etc.) may be interpreted as TTIs with a TTI length less than that of a long TTI but 1 ms or more.
[0129] A resource block (RB) is a resource allocation unit in the time domain and frequency domain, and in the frequency domain, it may contain one or more consecutive subcarriers. The number of subcarriers in an RB may be the same regardless of the neurology, for example, 12. The number of subcarriers in an RB may be determined based on the neurology.
[0130] Furthermore, the time domain of RB may contain one or more symbols and may be the length of one slot, one minislot, one subframe, or one TTI. One TTI, one subframe, etc., may each consist of one or more resource blocks.
[0131] One or more RBs may also be called a Physical RB (PRB), Sub-Carrier Group (SCG), Resource Element Group (REG), PRB pair, RB pair, etc.
[0132] Furthermore, a resource block may consist of one or more resource elements (REs). For example, one RE may be a radio resource area comprising one subcarrier and one symbol.
[0133] A Bandwidth Part (BWP), also known as a partial bandwidth, may represent a subset of consecutive common resource blocks (RBs) for a particular neurology system in a given carrier. These common RBs may be identified by an index of the RBs relative to a common reference point of the carrier. A Bandwidth Part (PRB) may be defined and numbered within a given BWP.
[0134] A BWP may include BWPs for UL (UL BWP) and BWPs for DL (DL BWP). One or more BWPs may be configured within a single carrier for a UE.
[0135] At least one of the configured BWPs may be active, and the UE does not need to assume that it will send or receive a given signal / channel outside of the active BWP. In this disclosure, terms such as "cell" and "carrier" may be read as "BWP".
[0136] The structures described above, such as wireless frames, subframes, slots, minislots, and symbols, are merely illustrative. For example, the number of subframes included in a wireless frame, the number of slots per subframe or wireless frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, and the number of symbols, symbol length, and cyclic prefix (CP) length within a TTI can be varied in various ways.
[0137] In this disclosure, if articles are added through translation, such as a, an, and the in English, this disclosure may include the fact that the noun following these articles is plural.
[0138] In this disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "combine" may be interpreted similarly to "different."
[0139] Each aspect / embodiment described herein may be used individually, in combination, or switched between as needed during implementation. Furthermore, notification of specific information (e.g., notification that "X is") is not limited to explicit notification, but may also be implicit (e.g., by not providing such notification).
[0140] In this disclosure, the HAPS relay system is an example of a non-ground device. The HAPS ground system is an example of a ground device.
[0141] Although the present disclosure has been described in detail above, it will be clear to those skilled in the art that the present disclosure is not limited to the embodiments described herein. The present disclosure can be implemented in modified and altered forms without departing from the intent and scope of the present disclosure as defined by the claims. Therefore, the descriptions in the present disclosure are illustrative and not intended to be restrictive in any way. [Explanation of Symbols]
[0142] 10 base station 110 Transmitter 120 Receiver 130 Setting section 140 Control Unit 20 devices 210 Transmitter 220 Receiver 230 Setting section 240 Control Unit 1001 Processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication device 1005 Input device 1006 Output device
Claims
1. A wireless communication system including non-ground equipment and ground equipment, The aforementioned non-ground device is, A first control unit establishes a service link with the terminal and a feeder link with the ground equipment, It has a first communication unit that relays between the service link and the feeder link, The aforementioned ground equipment is A second control unit establishes the feeder link with the non-ground equipment and the fronthaul with the base station, It has a second communication unit that converts the signal from the front hole and the signal from the feeder link to each other. The first control unit of the non-ground device is: A wireless communication system that, in the event of a deterioration in line quality, performs site diversity to establish a new feeder link with other ground equipment, performs inter-base station handover if the backhaul line is extended, and performs intra-base station handover if the fronthaul line is extended.
2. The aforementioned service link is direct access, The first control unit establishes a plurality of service links in the first band and establishes the feeder link in the second band. The first communication unit applies a beam to each of the plurality of service links and transmits and receives simultaneously. The second control unit establishes the feeder link in the second band, The wireless communication system according to claim 1, wherein the second communication unit bundles and transmits signals corresponding to the plurality of service links.
3. The aforementioned service link is configured as a CBH (Cellular Backhaul), The first control unit establishes a plurality of service links in the second band, and establishes the feeder link in the second band. The first communication unit applies a beam to each of the plurality of service links and transmits and receives simultaneously. The second control unit establishes the feeder link in the second band, The wireless communication system according to claim 1, wherein the second communication unit bundles and transmits signals corresponding to the plurality of service links.
4. The aforementioned service link is configured as direct access and CBH, The first control unit establishes a first plurality of service links in the first band, a second plurality of service links in the second band, and a feeder link in the second band. The first communication unit applies a beam to each of the first plurality of service links and transmits and receives simultaneously, and applies a beam to each of the second plurality of service links and transmits and receives simultaneously, The second control unit establishes the feeder link in the second band, The wireless communication system according to claim 1, wherein the second communication unit transmits and receives signals corresponding to the first plurality of service links and signals corresponding to the second plurality of service links in a bundle.
5. The wireless communication system according to claim 1, wherein, if the quality of the feeder link deteriorates, the first control unit switches the ground device that establishes the feeder link to another ground device and establishes a new feeder link, or uses a feeder link that was previously established with the other ground device.
6. A wireless communication method performed by a wireless communication system including non-ground equipment and ground equipment, The aforementioned non-ground device is, A first control procedure for establishing a service link with the terminal and a feeder link with the ground equipment, A first communication procedure is performed to relay the communication between the service link and the feeder link. The aforementioned ground equipment is A second control procedure for establishing the feeder link with the non-ground device and establishing the fronthaul with the base station, A second communication procedure is performed to mutually convert the signal from the front haul and the signal from the feeder link. The aforementioned non-ground device is, A wireless communication method that, in the event of a deterioration in line quality, performs site diversity to establish a new feeder link with other ground equipment, performs inter-base station handover if the backhaul line is extended, and performs intra-base station handover if the fronthaul line is extended.
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