Ground station device, wireless communication system, and wireless communication method

Abstract

The aim is to provide ground station equipment, wireless communication systems and wireless communication methods that are optimized through system integration while utilizing existing facilities such as 5G of each mobile network operator (MNO). [Solution] The ground station device 100 includes a receiving unit that receives signals from the ground network equipment of multiple telecommunications carriers via the same type of connection interface, a frequency conversion unit that applies a frequency shift for each telecommunications carrier to the radio frequencies carrying the signals of each of the multiple telecommunications carriers, and places them within a predetermined frequency band on a link to a relay station device of a non-terrestrial network, and a transmitting unit that transmits the radio signals of the multiple telecommunications carriers.

Description

[Technical Field]

[0001] The present disclosure relates to a ground station device, a wireless communication system, and a wireless communication method that are capable of cooperating with existing facilities such as 5G and that constitute a non-terrestrial network. [Background technology]

[0002] The 3rd Generation Partnership Project (3GPP: registered trademark) is developing specifications for the 5th generation mobile communication system (5G, also known as New Radio (NR) or Next Generation (NG)), and is also developing specifications for the next generation, known as Beyond 5G, 5G Evolution, or 6G.

[0003] Furthermore, in order to provide various services to areas that could not be covered by the current mobile communication network (Public Land Mobile Network: PLMN), which is mainly based on terrestrial networks, the introduction of non-terrestrial networks (NTN) is expected. NTN components include geostationary orbit satellites (GEO), low earth orbit satellites (LEO), and high-altitude platform stations (HAPS).

[0004] Therefore, research is being conducted into communication methods and network architectures that can link terrestrial networks, including 5G networks, with stratospheric networks using HAPS (see Non-Patent Document 1). Such linkage between 5G networks and HAPS will make it possible to build a HAPS system while utilizing existing 5G facilities, such as radio base stations (gNBs). [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] Hinata Obara and five others, "Development of a 38GHz band wireless communication system linked to a 5G network using a high altitude platform (HAPS) - A new HAPS system configuration utilizing ground network facilities," IEICE University, March 2022 Summary of the Invention [Problem to be solved by the invention]

[0006] When utilizing the core network and radio base stations of the terrestrial network, it is necessary to define the demarcation point between the mobile communication network equipment operated by the mobile network operator (MNO) and the terrestrial gateway (GW) station provided by the HAPS operator.

[0007] In particular, when multiple mobile network operators (MNOs) share a terrestrial gateway station, each company builds its own terrestrial network, so the extent to which the core network and radio base stations of the terrestrial network can be utilized may differ for each mobile network operator (MNO), making it desirable to connect at flexible functional division points.

[0008] Furthermore, each mobile network operator (MNO) will provide communication services to terrestrial UE via a shared terrestrial gateway station and relay station equipment in the sky, but the communication link (service link) between the relay station equipment and terrestrial UE will employ multi-beam transmission using the 4G or 5G frequency band allocated to each mobile network operator (MNO). In this case, the communication link (feeder link) between the terrestrial gateway station and relay station equipment must multiplex signals from each mobile network operator (MNO) according to the number of beams in the multi-beam, and the terrestrial gateway equipment requires an efficient multiplexing method.

[0009] Therefore, the following disclosure has been made in consideration of this situation, and aims to provide a ground station device, a wireless communication system, and a wireless communication method that are optimized through system integration, while utilizing existing facilities such as 5G of each mobile network operator (MNO), even when multiple mobile network operators (MNOs) share the ground station device. [Means for solving the problem]

[0010] One aspect of the present disclosure is a terrestrial station device (100) including a receiving unit (110, 120, 170) that receives signals from terrestrial network facilities of multiple telecommunications carriers via the same type of connection interface, a frequency conversion unit (130) that applies a frequency shift for each telecommunications carrier to a radio frequency carrying each of the signals of the multiple telecommunications carriers to convert the radio frequency into a frequency located within a predetermined frequency band on a link to a relay station device of a non-terrestrial network, and a transmitting unit (150) that transmits the frequency-converted radio signal to the relay station device.

[0011] One aspect of the present disclosure is a wireless communication system comprising a base station (50) of a first telecommunications carrier and a terrestrial station device (100) connected to the base station via a first type of connection interface, wherein the base station comprises a transmitter that transmits a first signal of the first telecommunications carrier and a second signal received via a second type of connection interface from terrestrial network equipment of a second telecommunications carrier to the terrestrial station device via the first type of connection interface, and the terrestrial station device comprises a receiver (110) that receives the first signal and the second signal via the first type of connection interface, a frequency converter (130) that applies a frequency shift for each telecommunications carrier to radio frequencies carrying the first signal and the second signal, respectively, to convert them into frequencies located within a predetermined frequency band on a link to a relay station device of a non-terrestrial network, and a transmitter (150) that transmits the frequency-converted radio signal to the relay station device.

[0012] One aspect of the present disclosure is a terrestrial station device (100) comprising: a receiving unit that receives signals from a plurality of telecommunications carriers that are allocated at predetermined intervals within a frequency band of a first link to a terminal of a relay station device of a non-terrestrial network; a frequency conversion unit (130) that applies a frequency shift to radio frequencies that carry each of the signals of the plurality of telecommunications carriers, and converts the frequencies of the plurality of telecommunications carriers into frequencies that are arranged at the predetermined intervals within the beam for each beam applied on the first link; and a transmitting unit (150) that transmits the frequency-converted radio signals on a second link to the relay station device.

[0013] One aspect of the present disclosure is a communication method for a terrestrial station device (100) comprising the steps of: receiving signals from a plurality of telecommunications carriers allocated at predetermined intervals within a frequency band of a first link to a terminal of a relay station device of a non-terrestrial network; applying a frequency shift to radio frequencies carrying the signals of the plurality of telecommunications carriers, for each beam applied on the first link, to convert the frequencies of the plurality of telecommunications carriers within the beam to frequencies arranged at the predetermined intervals; and transmitting the frequency-converted radio signals on a second link to the relay station device.

[0014] One aspect of the present disclosure is a communication method for a terrestrial station device (100) comprising the steps of: receiving signals from a plurality of telecommunications carriers, the signals being allocated in a predetermined arrangement within a frequency band of a first link to a terminal of a relay station device of a non-terrestrial network; applying a frequency shift to radio frequencies carrying the signals of the plurality of telecommunications carriers, thereby converting, for each of the telecommunications carriers, the frequencies of a plurality of beams applied on the first link to arranged frequencies; and transmitting the frequency-converted radio signals on a second link to the relay station device. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a diagram showing an example of the overall schematic configuration of a wireless communication system 10 according to this embodiment. [Figure 2]FIG. 2 is a diagram showing an example of a functional division point where a base station and a terrestrial gateway station are connected. [Figure 3] FIG. 3 is a diagram showing a configuration example (option 1) that employs RF division in this embodiment. [Figure 4] FIG. 4 is a diagram showing another configuration example (option 2) that employs RF division in this embodiment. [Figure 5] FIG. 5 is a diagram showing a configuration example (option 1) that employs fronthaul division in this embodiment. [Figure 6] FIG. 6 is a diagram showing another configuration example (option 2) that employs fronthaul division in this embodiment. [Figure 7] FIG. 7 is a diagram showing another configuration example (option 3) that employs fronthaul division in this embodiment. [Figure 8] FIG. 8 is a diagram showing an implementation example in which multiple MNOs are connected by RF division. [Figure 9] FIG. 9 is a diagram showing an implementation example in which multiple MNOs are connected by fronthaul splitting. [Figure 10] FIG. 10 is a diagram illustrating an implementation example in which multiple MNOs are connected by backhaul division. [Figure 11] FIG. 11 shows an example implementation of connecting multiple MNOs using a combination of fronthaul splitting and backhaul splitting. [Figure 12] FIG. 12 is a diagram showing an overview of frequency usage in a service link. [Figure 13] FIG. 13 is a diagram showing an example (option 1) of frequency multiplexing a plurality of MNO signals in this embodiment. [Figure 14] FIG. 14 is a diagram showing another example (option 2) of frequency multiplexing a plurality of MNO signals in this embodiment. [Figure 15] FIG. 15 is a diagram showing another example (option 3) of frequency multiplexing a plurality of MNO signals in this embodiment. [Figure 16]FIG. 16 is a diagram illustrating an example of the hardware configuration of a radio base station, a terrestrial gateway station, a HAPS payload, and a UE. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, embodiments will be described with reference to the drawings. Note that the same or similar reference numerals are used to designate the same functions or configurations, and descriptions thereof will be omitted as appropriate.

[0017] (1) Example of overall schematic configuration of wireless communication system Fig. 1 shows an example of the overall schematic configuration of a wireless communication system 10 according to this embodiment. As shown in Fig. 1, the wireless communication system 10 includes a wireless base station 50 (hereinafter, gNB 50), a ground station device 100, a relay station device 200, and a UE 300. In Fig. 1, the ground station device 100 is a terrestrial gateway (GW) station, and the relay station device 200 is a HAPS relay station (e.g., a HAPS payload).

[0018] In FIG. 1, a core network of a mobile network operator (MNO) and a wireless base station 50 are utilized, and 4G and 5G wireless signals are transmitted to a UE via a terrestrial gateway station 100 and a HAPS payload 200. This figure shows a configuration called a bent pipe (transparent relay type) system that provides direct communication services to 300.

[0019] The gNB 50 (gNode B) is a radio base station conforming to 5G (NR). The gNB 50 performs 5G wireless communication with the UE 300 via the terrestrial gateway station 100 and the HAPS payload 200. The gNB 50 may be connected to a 5G core network (CN) via a backhaul (link). Note that the gNB 50 and the UE 300 may support not only 5G but also other mobile communication methods, such as 4G / LTE (Long Term Evolution), Beyond 5G, 5G Evolution, or 6G.

[0020] The feeder link, which is the communication link between the terrestrial gateway station 100 and the HAPS payload 200, uses a high frequency band such as millimeter waves, and transmits signals from multiple cell beams over a wide bandwidth by wavelength multiplexing.

[0021] The HAPS payload 200 does not perform signal processing such as modulation and demodulation, but operates as a relay system that performs frequency conversion and power amplification between the feeder link and the service link.

[0022] The service link, which is a communication link between the HAPS payload 200 and the ground UE, simultaneously transmits spatially divided signals in multiple cell beams using, for example, a 4G or 5G frequency band available to the UE 300. The service link may also use a frequency (2.7 GHz or less) allocated for HAPS among the 4G or 5G frequencies available to the UE 300.

[0023] (2) Overview of Demarcation Points How to define the functional division point between the existing facilities operated by the mobile network operator (MNO) and the ground gateway station provided by the HAPS operator is important for system integration.

[0024] FIG. 2 shows an example of a functional division point where a base station and a terrestrial gateway station are connected.

[0025] Figure 2(a) shows an example of an RF splitting option.

[0026] With RF splitting, RUs extending from 5G network base stations (CU / DU) are connected to the HAPS gateway function of the terrestrial gateway station via RF cables. This RF splitting makes it possible to make maximum use of the mobile communication network facilities operated by mobile network operators (MNOs). In order to utilize all of the base stations (CU / DU) and radio units (RU) from the core network, the input / output interface with the terrestrial gateway station is an RF signal (for example, the 2 GHz band).

[0027] Figure 2(b) shows an example of a fronthaul splitting option.

[0028] With fronthaul splitting, the core network and base stations (CU / DU) of the mobile communications network equipment are utilized, and an interface using a fronthaul optical fiber transmission line is used for input and output with the terrestrial gateway station. Specific fronthaul interfaces that can be applied include CPRI (Common Public Radio Interface) or eCPRI for LTE, and O-RAN (Open RAN) standards for 5G. HAPS operators have the potential to integrate the gateway functions of the RU and HAPS to create an optimized terrestrial gateway station (joint optimization), potentially reducing equipment size and power consumption.

[0029] Figure 2 (c) shows an example of a backhaul split option. In backhaul split, only the core network is used for mobile communication network equipment, and the HAPS operator provides a terrestrial gateway station that integrates base station, RU, and HAPS gateway functions. Because the system also includes base stations, there is the greatest room for optimization (joint optimization).

[0030] (3) Configuration of this embodiment In this embodiment, an example is shown assuming a system in which 8 carriers are multiplexed using 4 beams and 2-layer MIMO multiplexing in the service link.

[0031] (3.1) Example of RF division configuration (i) Option 1 Fig. 3 shows a configuration example (option 1) employing RF division in this embodiment. In Fig. 3, the gNB 50 and the terrestrial GW station 100 (for example, the HAPS GW 100) are connected by eight RF cables (S-band), and RF signals are exchanged between them.

[0032] The gNB 50 is composed of a CU and DU. The CU and DU may be installed in an integrated configuration, or may be installed in remote locations as an extension type. Four RUs are connected to the gNB 50 via optical fiber, and an interface conforming to the O-RAN standard is applied. For this reason, the DU of the gNB 50 may be an O-DU (O-RAN Distribution Unit).

[0033] The radio unit 51 is, for example, a radio unit RU, and may be an O-RU (O-RAN Radio Unit) when an interface conforming to the O-RAN standard is applied. One RU has two antenna ports and corresponds to one cell, so Fig. 3 shows an example of a four-cell configuration. The radio unit 51 includes a function for converting between fronthaul optical line signals and analog OFDM signals.

[0034] The HAPS GW 100 is composed of a duplexer DUP 120, a frequency conversion unit 130, a multiplexing / demultiplexing unit 140, and a radio transmission / reception unit 150. The HAPS GW 100 frequency-multiplexes and transmits signals from each cell on the feeder link.

[0035] The duplexer DUP120 is connected to the antenna port of the RU in a one-to-one correspondence and includes a function for separating the uplink and downlink frequencies.

[0036] The frequency conversion unit 130 is composed of, for example, 16 analog frequency converters. The frequency conversion unit 130 applies different frequency shifts to the frequency of the radio signal to convert it into a frequency within a predetermined frequency band on the link to the relay station device. Because a high frequency band (e.g., Q-band) such as millimeter waves is used for the feeder link with the HAPS payload 200, the frequency conversion (upconversion) is performed by applying a frequency shift so that the radio signals from each cell can be multiplexed in the high frequency band. Specifically, to frequency-multiplex and transmit signals from four cells on the feeder link, the signals from each cell antenna port are multiplexed by shifting their frequencies. The frequency conversion unit 130 also performs the reverse conversion (downconversion) on the radio signals received from the feeder link.

[0037] The multiplexer / demultiplexer 140 is composed of, for example, a multiplexer (MUX) and a demultiplexer (DEMUX), and multiplexes multiple frequencies in the frequency domain and outputs them as a frequency-multiplexed signal, or separates each radio frequency from the frequency-multiplexed signal and outputs it.

[0038] The radio transceiver unit 150 is composed of, for example, a radio transmitter (TX RF), a radio receiver (RX RF), and an antenna, and relays frequency-multiplexed radio signals to the HAPS payload 200 located in the sky using a high frequency band, for example, millimeter waves.

[0039] In this way, in Option 1, the HAPS GW100 can be connected to the RU51 of the base station (CU / DU)50 via an RF cable, making it possible to make maximum use of much of the existing equipment in the terrestrial network.

[0040] (ii) Option 2 FIG. 4 shows another configuration example (option 2) that employs RF division in this embodiment.

[0041] The multiplexer / demultiplexer 160 is composed of, for example, a multiplexer (MUX) and a demultiplexer (DEMUX).

[0042] The difference from Figure 3 is that in Figure 4, some radio units 51, specifically RU#2 to RU#4, are configured to apply a predetermined frequency shift within a predetermined band (S-band) for each RU as the radio frequency for carrying signals, and that in HAPS GW100, multiplexing / demultiplexing unit 160 multiplexes and demultiplexes the radio frequencies of RU#1 to RU#4 for each antenna port, and inputs / outputs them to frequency conversion unit 130.

[0043] In this way, compared to Option 1, Option 2 can reduce the number of frequency conversion units 130, specifically the number of analog frequency converters, from 16 to 4, making it possible to reduce power consumption and miniaturize the device in the HAPS GW100.

[0044] (3.2) Example of a configuration with split fronthaul (i) Option 1 Fig. 5 shows a configuration example (option 1) that employs fronthaul division in this embodiment. In Fig. 5, the gNB 50 and the HAPS GW 100 are connected by four optical fibers.

[0045] The gNB 50 is composed of a CU / DU. The CU / DU may be installed in an integrated configuration, or may be installed in remote locations as an extended configuration. The gNB 50 has an O-DU that is connected to the HAPS GW 100 via, for example, an interface conforming to the O-RAN standard.

[0046] Meanwhile, the HAPS GW 100 is composed of a radio unit 110, a duplexer (DUP) 120, a frequency conversion unit 130, a multiplexer / demultiplexer unit 140, and a radio transceiver unit 150.

[0047] The radio unit 110 may be, for example, radio units RU#1 to RU#4, which may be O-RUs connected to the gNB 50 via an interface conforming to the O-RAN standard. One RU has two antenna ports and corresponds to one cell, so FIG. 5 shows an example of a four-cell configuration. Each antenna port is connected one-to-one to the duplexer 120 via an RF cable (S-band). The radio frequency from the antenna port is input / output to / from the frequency conversion unit 130 via the duplexer DUP120.

[0048] The RU includes a function for converting between fronthaul optical line signals and analog OFDM signals (radio signals). Specifically, in the case of an O-RU, the O-RU receives from the O-DU an IQ sampling sequence (also called a baseband signal) of a frequency-domain OFDM signal after processing such as encoding and scrambling has been performed on the user bit sequence. The O-RU converts the IQ sampling sequence into a time-domain OFDM signal using an Inverse Fast Fourier Transform (IFFT) process, and then converts it into an analog signal. The radio unit 110 may constitute a radio unit that converts multiple baseband signals received from base stations of a terrestrial network into radio frequencies using a carrier frequency. In this case, the O-DU of the gNB 50 may constitute a transmitter that transmits multiple baseband signals.

[0049] The duplexer DUP120 includes a function for separating the uplink and downlink frequencies.

[0050] The frequency conversion unit 130 may be configured with, for example, 16 analog frequency converters. The frequency conversion unit 130 may be configured to apply different frequency shifts to the frequency of a radio signal to convert it into a frequency within a predetermined frequency band on a link to a relay station device of a non-terrestrial network. Because a high frequency band (e.g., Q-band) such as millimeter waves is used for the feeder link with the HAPS payload 200, frequency shifts are applied to convert the radio signals from each cell so that they can be multiplexed in the high frequency band (upconversion). Specifically, to frequency-multiplex and transmit signals from four cells on the feeder link, the frequencies of the signals from each cell antenna port are shifted and multiplexed. For example, to prevent the frequencies of the radio signals from each cell antenna port from overlapping on the feeder link, different frequency shift amounts may be set based on the cell and / or antenna port, and the set frequency shift amount may be applied to the radio frequency of the signal from each cell antenna port. Furthermore, on the feeder link after frequency multiplexing, the frequencies of the signals from each cell antenna port may be multiplexed at predetermined intervals or with some gaps. Furthermore, the reverse conversion (down-conversion) is performed on radio signals received from the feeder link.

[0051] The multiplexer / demultiplexer 140 is composed of, for example, a multiplexer (MUX) and a demultiplexer (DEMUX), and multiplexes multiple frequencies in the frequency domain and outputs them as a frequency-multiplexed signal, or separates each radio frequency from the frequency-multiplexed signal and outputs it.

[0052] The wireless transceiver 150 is configured, for example, with a wireless transmitter (TX RF), a wireless receiver (RX RF), and an antenna, and relays frequency-multiplexed wireless signals using a high frequency band, for example, millimeter waves, to and from the HAPS payload 200 located in the sky. The wireless transceiver 150 may constitute a transmitter that transmits wireless signals including multiple wireless frequencies arranged within a predetermined frequency band to a relay station device.

[0053] In this way, compared to Option 1 with RF division, Option 1 reduces the number of cables from eight to four, making it easier to handle. In addition, because optical fiber is used instead of RF cables, even base stations deployed in remote locations can be connected to the HAPS GW100, improving scalability.

[0054] (ii) Option 2 FIG. 6 shows another configuration example (option 2) that employs fronthaul division in this embodiment.

[0055] The multiplexer / demultiplexer 160 is composed of, for example, a multiplexer (MUX) and a demultiplexer (DEMUX).

[0056] The difference from Figure 5 is that Figure 6 is configured such that RU#2 to RU#4 are configured to apply a predetermined frequency shift within a predetermined band (S-band) for each cell as the radio frequency that carries the signal, and that the multiplexer / demultiplexer 160 multiplexes and demultiplexes the radio frequencies of RU#1 to RU#4 for each antenna port, and inputs and outputs them to the frequency converter 130.

[0057] Specifically, the carrier frequencies of signals from the four cells are shifted on the S-band. For example, in RU#2 to RU#4, different frequency shift amounts may be set based on the cell so that the carrier frequencies of signals from each of the four cell antenna ports do not overlap on the S-band, and the frequency shift amount may be applied to the carrier frequency of the cell. RU#1 of the radio unit 110 may constitute a first radio unit that converts a first baseband signal received from a base station of a terrestrial network into a first radio frequency using the carrier frequency. RU#2 to RU#4 of the radio unit 110 may constitute a second radio unit that converts a second baseband signal received from a base station into a second radio frequency using a carrier frequency to which the frequency shift has been applied.

[0058] The frequency converter 130 performs frequency conversion (up-conversion) for frequency multiplexing and transmission on the feeder link for each antenna port. The frequency converter 130 may be configured as a frequency converter that converts the frequency of the first radio signal (radio signal from RU #1) and the frequency of the second radio signal (at least one of the radio signals from RU #2 to RU #4) into a frequency that is placed within a predetermined frequency band on the link to the relay station device of the non-terrestrial network.

[0059] In this way, compared to Option 1, Option 2 can reduce the number of frequency conversion units 130, specifically the number of analog frequency converters, from 16 to 4, making it possible to reduce power consumption and miniaturize the device in the HAPS GW100.

[0060] (iii) Option 3 FIG. 7 shows another configuration example (option 3) that employs fronthaul division in this embodiment.

[0061] 5 and 6 in that Fig. 7 includes a digital processing unit 170 that digitally processes the predetermined frequency shift required to place each of the multiple signals received over multiple O-RAN-compliant interfaces at a predetermined position within a predetermined frequency band (Q-band) on the feeder link, and that a TRX (Transmitter-Receiver) in the RU is not required. This predetermined frequency band may be the frequency band on the feeder link.

[0062] The digital processing unit 170 is configured, for example, by a DSP (Digital Signal Processor). The digital processing unit 170 converts multiple baseband signals received from a base station into radio frequencies to which different frequency shifts have been applied, thereby converting the signals into frequencies located within a predetermined frequency band on a link to a relay station device of a non-terrestrial network. Specifically, in order to frequency-multiplex and transmit signals from four cells on a feeder link, the signals from each cell antenna are multiplexed by shifting their frequencies. For example, to prevent the frequencies of radio signals from each cell antenna port (equivalent) from overlapping on the feeder link, different frequency shift amounts may be set based on the cell and / or antenna port (equivalent), and the set frequency shift amount may be applied to the radio frequency of the signal from each cell antenna port (equivalent). Furthermore, on the feeder link after frequency multiplexing, the frequencies of the signals from each cell antenna port (equivalent) may be multiplexed at predetermined intervals or with some gaps. Furthermore, the reverse conversion is performed on radio signals received from the feeder link.

[0063] In this way, compared to Options 1 and 2, Option 3 eliminates the need for frequency conversion units, specifically, analog frequency converters and power amplifiers within the RU, enabling significant reductions in power consumption and miniaturization of the equipment.

[0064] (4) Expansion to multiple mobile network operators (MNOs) A configuration in which a plurality of mobile network operators (MNOs) share a HAPS system will be described. The mobile network operators (MNOs) may be included in the telecommunications carriers.

[0065] (4.1) Connection configuration example Below is an example of an implementation where multiple mobile network operators (MNOs) share a HAPS system and connect each company's network to a ground gateway station (HAPS GW).

[0066] (i) Option 1 FIG. 8 shows an example implementation of connecting multiple mobile network operators (MNOs) with RF splitting.

[0067] In Fig. 8, multiple mobile network operators (MNOs), namely, Company A, Company B, and Company C, each connect the RUs of their existing 5G networks via RF cables (S-band) to the HAPS GW function of a terrestrial GW station via an RF interface. In this case, in Fig. 3 and Fig. 4 showing the RF division, RU#1 to RU#4 correspond to the RUs of Company A, Company B, or Company C, and the duplexer 120 of the HAPS GW 100 may constitute a receiving unit that receives signals from each company.

[0068] The terrestrial gateway station 100 converts the frequencies of the signals from companies A, B, and C together into frequencies on the feeder link and transmits them to the HAPS payload 200. On this feeder link, frequency multiplexing may be used as described later in Figures 13, 14, and 15.

[0069] HAPS payload 200 applies multiple beams at the service link frequency and transmits them toward the ground, allowing UEs to receive communication services in the frequency bands allocated by each company. Specifically, as shown in Fig. 8, HAPS payload 200 controls four beams with different directions within the frequency bands allocated to companies A, B, and C on the service link to cover the ground with four cells, and provides communication services to UEs in each cell by spatially dividing and transmitting signals from multiple cells / beams.

[0070] In Fig. 8, the three companies use consecutive frequency bands for the service link, but other frequency usage methods may be used as will be described later in Fig. 12. Also, in Fig. 8, an example of a multi-beam beam pattern common to all companies is shown, but the three companies may use individual beam patterns.

[0071] In this way, Option 1 allows multiple mobile network operators (MNOs) to use existing network facilities as is, making it easy to provide HAPS services to UEs.

[0072] (ii) Option 2 Figure 9 shows an implementation example of connecting multiple mobile network operators (MNOs) with fronthaul splitting.

[0073] The difference from Figure 8 is that in Figure 9, multiple mobile network operators (MNOs) A, B, and C each connect the DUs of their existing 5G networks to the RUs of the terrestrial gateway station via optical fiber (for example, an interface conforming to the O-RAN standard). In this case, the optical fiber shown in Figures 5, 6, and 7, which show the fronthaul division, connects to the base station of one of the companies A, B, or C.

[0074] In this case, part of the radio section 110 shown in FIG. 5 or FIG. 6 or the digital processing section 170 shown in FIG. 7 may constitute a receiving section that receives signals from each company.

[0075] In this way, compared to Option 1, Option 2 simplifies the use of existing network equipment at multiple mobile network operators (MNOs) by utilizing optical fiber and O-RAN standard interfaces, and can be used even if the location of the terrestrial gateway station and the location of each company's network equipment are far apart.

[0076] (iii) Option 3 FIG. 10 shows an implementation example of connecting multiple mobile network operators (MNOs) with backhaul splitting.

[0077] The difference from Figures 8 and 9 is that in Figure 10, multiple mobile network operators (MNOs) A, B, and C each connect their existing 5G core networks to a terrestrial gateway station via optical fiber (e.g., an NG standard interface). The CU function of the terrestrial gateway station includes a receiver (not shown) that receives signals from each company.

[0078] In this way, Option 3 allows each company's core network to be connected via optical fiber to a terrestrial gateway station with base station functions provided by the HAPS operator, making it easy to connect without relying on the configuration of each company's base station.

[0079] (iv) Option 4 FIG. 11 illustrates an implementation example in which multiple mobile network operators (MNOs) are connected using a combination of fronthaul and backhaul splitting.

[0080] In FIG. 11, only the base station (CU / DU) of company A is connected to the terrestrial gateway station via optical fiber using an interface conforming to the O-RAN standard. This is an implementation example in which companies B and C connect their respective core networks to company A's base station via optical fiber using an interface conforming to the NG standard. The interface conforming to the O-RAN standard may be a first-type connection interface, and the interface conforming to the NG standard may be a second-type connection interface. The DU of base station 50 may constitute a transmission unit.

[0081] In this way, Option 4 makes it possible to connect to terrestrial gateway stations depending on the existing equipment situation of each mobile network operator (MNO), allowing for flexible sharing of HAPS services.

[0082] Although FIG. 11 shows an example of a combination of fronthaul division and backhaul division, it is also possible to combine any of RF division, fronthaul division, and backhaul division.

[0083] (4.2) Example of frequency usage for service links When multiple mobile network operators (MNOs) share HAPS services, each company provides communication services to UE on the ground via a shared terrestrial gateway station and relay station equipment in the sky. The service link between the relay station equipment and UE on the ground uses multi-beam transmission using the 4G or 5G frequency bands allocated to each MNO. In this case, the feeder link between the terrestrial gateway station and relay station equipment must multiplex signals from each MNO according to the number of beams in the multi-beam, requiring frequency shifts to accommodate this.

[0084] FIG. 12 shows an overview of frequency usage in the service link.

[0085] Figure 12(a) shows an example (Option 1) in which each company uses a contiguous frequency band for HAPS services, just like for terrestrial networks. For example, each company uses a contiguous 20 MHz bandwidth.

[0086] Figure 12(b) shows an example (Option 2) in which each company uses frequency bands at regular intervals for HAPS services. For example, of the 20 MHz bands allocated to each company, the highest frequency band of 10 MHz is used for HAPS services.

[0087] Figure 12 (c) shows an example (Option 3) in which each company freely uses frequency bands for HAPS services. The frequency bands that each company uses for HAPS services must be coordinated with the frequency usage of terrestrial networks, so the frequency bands that each company can provide for HAPS may differ. For example, Company A uses the entire 20 MHz bandwidth, Company B uses the higher 10 MHz of the 20 MHz bandwidth, and Company C uses the lower 10 MHz of the 20 MHz bandwidth.

[0088] Figure 12(d) shows an example (Option 4) in which a dedicated frequency band for HAPS use is secured and shared by all companies, unlike Figure 12(a), (b), and (c). In this case, each company can use available bands in the dedicated frequency band as appropriate.

[0089] In addition, there are two methods for multi-beam beam patterns applied to service links: one is to use a common beam pattern for each company, and the other is to use an independent beam pattern for each company. The two beam patterns can be applied to any of the four frequency usage methods shown in Figure 12.

[0090] When the beam patterns common to all companies are applied to Figures 12(a), (b), and (c), a wide frequency bandwidth can be obtained, as will be described later in Figures 13, 14, and 15, but there are various options for frequency multiplexing methods in feeder links.

[0091] When a beam pattern common to all companies is applied to Figure 12(d), the level is equivalent to that of operation by a single telecommunications carrier, and the system can be simplified.

[0092] (4.3) Example of frequency usage for feeder links This paper describes how to multiplex the frequencies of each company on the feeder link when multiple mobile network operators (MNOs) share HAPS services.

[0093] 13, 14, and 15 show frequency multiplexing methods for frequencies of each company on a feeder link when a beam pattern (number of beams: 4) common to all companies is adopted.

[0094] FIG. 13 shows an example (option 1) of frequency multiplexing of signals from multiple MNOs in this embodiment, in which consecutive frequencies are used for the frequencies of each company.

[0095] Figure 13 (a) shows an example in which the order of frequencies for each company is maintained within each beam. That is, for example, within beam #1, the order of frequencies for companies A, B, and C is maintained the same as the order of frequencies for the service link, and is frequency multiplexed on the feeder link together with other beams #2 to #4. In this example, the terrestrial gateway station applies a large frequency shift to the consecutive frequencies of each company's signal for each beam, and frequency conversion can be performed collectively for each company's frequency, which has the advantage that frequency conversion for each beam can be completed in one step. This is easy to implement.

[0096] Figure 13(b) shows an example in which beams are arranged collectively for each company. That is, for example, the frequencies of signals from company A are arranged collectively from beams #1 to #4. In this example, the terrestrial gateway station first applies a small frequency shift to each beam, and then applies a large frequency shift to each company so that the order is the same as the order of the frequencies of each company in the service link, resulting in a two-step implementation.

[0097] FIG. 14 shows another example (option 2) of frequency multiplexing of signals from multiple MNOs in this embodiment, in which each company uses frequency bands at regular intervals.

[0098] FIG. 14(a) shows an example in which the spacing between the frequencies of each company is maintained within each beam. That is, for example, in beam #1, the spacing between the frequencies of companies A, B, and C is maintained the same as the spacing between the frequencies in the service link, and these are frequency-multiplexed on the feeder link together with other beams #2 to #4. In this example, the terrestrial gateway station applies a large frequency shift to the frequencies of each company's signal, which are spaced at regular intervals, for each beam. Since frequency conversion can be performed collectively for each company's frequency, there is an advantage in that frequency conversion for each beam can be completed in one step. Note that if the frequency spacing within each beam is narrowed to avoid gaps on the feeder link, further frequency shifts may be applied.

[0099] Figure 14(b) shows an example in which beams are grouped together for each company. That is, for example, the frequencies of signals from company A are grouped together and arranged as beams #1 to #4. In this example, the terrestrial gateway station first applies a small frequency shift to each beam, and then applies a frequency shift to each company so that the order of frequencies is the same as the order of frequencies for each company in the service link. This is a two-step implementation, but it enables compact frequency multiplexing on the feeder link.

[0100] FIG. 15 shows another example (option 3) of frequency multiplexing of signals from multiple MNOs in this embodiment, in which each company freely uses the frequency band.

[0101] FIG. 15(a) shows an example in which the frequency spacing between each company is maintained within each beam. That is, for example, in beam #1, the frequency spacing between companies A, B, and C is maintained the same as the frequency spacing in the service link, and is frequency-multiplexed on the feeder link together with other beams #2 to #4. In this example, the terrestrial gateway station applies a large frequency shift to the frequencies of each company's signal at a predetermined interval for each beam, and since frequency conversion can be performed collectively for each company's frequency, there is an advantage that frequency conversion for each beam can be completed in one step. Note that if the frequency spacing within each beam is narrowed to avoid gaps on the feeder link, a further frequency shift may be applied.

[0102] (b) of Figure 15 is an example in which beams are arranged collectively for each company. That is, for example, the frequencies of signals from company A are arranged collectively from the frequencies of beams #1 to #4. In this example, the terrestrial gateway station first applies a frequency shift for each beam, and then applies a frequency shift for each company so that the order is the same as the order of the frequencies for each company in the service link, resulting in a two-step implementation. The amount of frequency shift for each beam may be the same for each company, or may be different for each company so that no gaps occur.

[0103] The frequency multiplexing methods shown in FIGS. 13, 14, and 15 can be applied to the terrestrial gateway stations 100 in FIGS.

[0104] The frequency conversion unit 130 of the terrestrial GW station 100 shown in Figures 4 to 6 and the digital processing unit 170 of the terrestrial GW station shown in Figure 7 may configure a frequency conversion unit that applies a frequency shift to the radio frequencies that carry the signals of each of the multiple telecommunications carriers, and converts the frequencies of the multiple telecommunications carriers into frequencies that are arranged at predetermined intervals within the beam, for each beam applied on the service link. Also, the frequency conversion unit 130 of the terrestrial GW station 100 shown in Figures 4 to 6 and the digital processing unit 170 of the terrestrial GW station shown in Figure 7 may configure a frequency conversion unit that applies a frequency shift to the radio frequencies that carry the signals of each of the multiple telecommunications carriers, and converts the frequencies of the multiple beams applied on the service link into frequencies that are arranged within the beam, for each telecommunications carrier.

[0105] The frequency shift amount for each company and the frequency shift amount required for each beam may be notified appropriately or may be set in advance in the ground station gateway station 100. Furthermore, these shift amounts and frequency multiplexing methods may be shared with the HAPS payload 200 so that the HAPS payload 200 can correctly transmit the frequencies multiplexed on the feeder link over the service link.

[0106] According to the above-described embodiment, the following advantageous effects can be obtained.

[0107] Specifically, the terrestrial gateway station receives signals from the terrestrial network equipment of multiple telecommunications carriers via the RF interface, O-RAN interface, or NG interface, applies frequency shifts for each telecommunications carrier to the radio frequencies carrying each of the multiple telecommunications carriers' signals, converts them to frequencies located within a specified frequency band on the link to the HAPS payload, and transmits the frequency-converted radio signals to the HAPS payload.

[0108] This will allow each telecommunications carrier to utilize their existing terrestrial network facilities while sharing terrestrial gateway stations with other telecommunications carriers.

[0109] In addition, in a wireless communication system consisting of a base station of a first telecommunications carrier and a terrestrial gateway station connected to the base station via an O-RAN interface, the base station transmits a first signal of the first telecommunications carrier and a second signal received via the NG interface from terrestrial network equipment of a second telecommunications carrier to the terrestrial gateway station via the O-RAN interface, and the terrestrial gateway station receives the first signal and the second signal via the O-RAN interface, applies a frequency shift for each telecommunications carrier to the radio frequencies carrying the first signal and the second signal, respectively, to convert them to frequencies located within a predetermined frequency band on the link to the HAPS payload, and transmits the frequency-converted radio signal toward the HAPS payload.

[0110] This will enable each telecommunications carrier to connect to terrestrial gateway stations to the extent that they can utilize the existing terrestrial network facilities they have built themselves, thereby increasing the opportunities for sharing terrestrial gateway stations.

[0111] In addition, the terrestrial gateway station receives signals from multiple telecommunications carriers that are allocated at predetermined intervals within the frequency band of the service link for the terminal of the HAPS payload, applies frequency shifts to the radio frequencies that carry each of the signals of the multiple telecommunications carriers, and converts the frequencies of the multiple telecommunications carriers into frequencies that are arranged at predetermined intervals within the beam for each beam applied on the service link, and transmits the frequency-converted radio signals on the feeder link for the HAPS payload.

[0112] This allows multiple telecommunications carriers to be placed on the feeder link while maintaining a predetermined spacing between them for each beam, even when the respective telecommunications carriers share a terrestrial gateway station.

[0113] In addition, the terrestrial W station receives signals from multiple telecommunications carriers that are allocated in a predetermined arrangement within the frequency band of the service link for the terminal of the HAPS payload, applies frequency shifts to the radio frequencies carrying each of the signals of the multiple telecommunications carriers, converts the frequencies of the multiple beams applied on the service link for each telecommunications carrier into arranged frequencies, and transmits the frequency-converted radio signals on the feeder link to the relay station device.

[0114] This allows multiple beams to be placed on the feeder link for each telecommunications carrier without any gaps, even if each carrier shares a terrestrial gateway station.

[0115] (5) Other embodiments The contents of the present proposal have been explained above in accordance with the embodiments, but it will be obvious to those skilled in the art that the present proposal is not limited to these descriptions and that various modifications and improvements are possible.

[0116] For example, in the above-described embodiment, an example was given of a system in which the service link has four beams and eight carriers multiplexed by two-layer MIMO multiplexing, but other numbers of beams, layers, and carrier multiplexing numbers may also be used.

[0117] In the above-described embodiment, the gNB 50 is a radio base station conforming to 5G, but the radio base station and related network nodes may conform to a system other than 5G (4G, 6G, etc.) as long as they have a similar RU configuration. Also, in the above-described embodiment, functions in the downlink (DL) direction have been mainly described, but the gNB 50, terrestrial GW station 100, and HAPS payload 200 may have functions in the uplink (UL) direction that correspond to those in the DL direction (performing processing opposite to that in the DL direction).

[0118] In the above-described embodiment, the HAPS relay station 200 is assumed to be located in the sky, but the HAPS relay station 200 does not necessarily have to be located in the sky temporarily or permanently. For example, the HAPS relay station 200 may be provided on top of a structure having a certain altitude, or may be mounted on a stationary object in the sky that does not fly in circles.

[0119] Also, in the above description, "configure," "activate," "update," "indicate," "enable," "specify," and "select" may be interchangeable. Similarly, "link," "associate," "correspond," and "map" may be interchangeable, and "allocate," "assign," "monitor," and "map" may also be interchangeable.

[0120] Furthermore, specific, dedicated, UE-specific, and UE-dedicated may be interchangeable. Similarly, common, shared, group-common, UE-common, and UE-shared may be interchangeable.

[0121] The block diagrams (e.g., FIGS. 3 and 4) used in the description of the above-described embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are connected directly or indirectly (e.g., by wire, wirelessly, etc.) and these multiple devices. The functional block may also be realized by combining software with the single device or multiple devices.

[0122] Functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission is called a transmitting unit or transmitter. As mentioned above, there are no particular limitations on how each is implemented.

[0123] Furthermore, the above-described gNB 50, HAPS ground system 100, HAPS relay system 200, and UE 300 (the devices) may function as a computer that performs processing of the wireless communication method of the present disclosure. Figure 16 is a diagram showing an example of the hardware configuration of the devices. As shown in Figure 16, the devices may be configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0124] In the following description, the term "apparatus" can be interpreted as a circuit, a device, a unit, etc. The hardware configuration of the apparatus may be configured to include one or more of the apparatuses shown in the drawings, or may be configured to exclude some of the apparatuses.

[0125] Each functional block of the device (FIGS. 3, 4, etc.) is realized by any hardware element of the computer device or a combination of the hardware elements.

[0126] In addition, each function of the device is realized by loading specified software (programs) onto hardware such as processor 1001 and memory 1002, causing processor 1001 to perform calculations, control communication via communication device 1004, and control at least one of reading and writing data in memory 1002 and storage 1003.

[0127] The processor 1001 controls the entire computer by running, for example, an operating system, and may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control unit, an arithmetic unit, a register, and the like.

[0128] The processor 1001 also reads programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and executes various processes in accordance with these. The programs used are those that cause a computer to execute at least some of the operations described in the above-mentioned embodiments. Furthermore, the various processes described above may be executed by one processor 1001, or may be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The programs may be transmitted from a network via a telecommunications line.

[0129] The memory 1002 is a computer-readable recording medium and may be configured by, for example, at least one of a read-only memory (ROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a random access memory (RAM), etc. The memory 1002 may also be called a register, a cache, a main memory (primary storage device), etc. The memory 1002 can store a program (program code), a software module, etc., that can execute a method according to an embodiment of the present disclosure.

[0130] Storage 1003 is a computer-readable recording medium, and may be, for example, at least one of an optical disk such as a Compact Disc ROM (CD-ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disk, a digital versatile disk, a Blu-ray disc), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy disk, a magnetic strip, etc. Storage 1003 may also be referred to as an auxiliary storage device. The above-mentioned recording medium may be, for example, a database, a server, or other appropriate medium including at least one of memory 1002 and storage 1003.

[0131] The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also called, for example, a network device, a network controller, a network card, or a communication module.

[0132] The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize, for example, at least one of Frequency Division Duplex (FDD) and Time Division Duplex (TDD).

[0133] The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives input from the outside. The output device 1006 is an output device (for example, a display, a speaker, an LED lamp, etc.) that outputs to the outside. The input device 1005 and the output device 1006 may be integrated into one device (for example, a touch panel).

[0134] Furthermore, each device such as the processor 1001 and the memory 1002 is connected to a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0135] Furthermore, the device may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized by the hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0136] Furthermore, the notification of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods. For example, the notification of information may be performed by physical layer signaling (e.g., Downlink Control Information (DCI), Uplink Control Information (UCI)), higher layer signaling (e.g., RRC signaling, Medium Access Control (MAC) signaling, broadcast information (Master Information Block (MIB), System Information Block (SIB))), other signals, or a combination thereof. Furthermore, the RRC signaling may be referred to as an RRC message, and may be, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, or the like.

[0137] Each aspect / embodiment described in the present disclosure may be applied to at least one of a system using Long Term Evolution (LTE), LTE-Advanced (LTE-A), SUPER 3G, IMT-Advanced, a 4th generation mobile communication system (4G), a 5th generation mobile communication system (5G), a 6th generation mobile communication system (6G), an xth generation mobile communication system (xG) (where x is, for example, an integer or a decimal), Future Radio Access (FRA), New Radio (NR), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), or other suitable systems, and next-generation systems enhanced based on these. In addition, a combination of multiple systems (for example, a combination of at least one of LTE and LTE-A with 5G) may be applied.

[0138] The order of the procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be changed unless it is consistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the particular order presented.

[0139] In the present disclosure, a specific operation described as being performed by a base station may also be performed by its upper node in some cases. In a network consisting of one or more network nodes having a base station, it is clear that various operations performed for communication with a terminal may be performed by at least one of the base station and another network node other than the base station (for example, an MME or an S-GW, etc., but are not limited to these). Although the above example illustrates a case where there is one other network node other than the base station, a combination of multiple other network nodes (for example, an MME and an S-GW) may also be used.

[0140] Information, signals (information, etc.) may be output from a higher layer (or a lower layer) to a lower layer (or a higher layer), or may be input / output via multiple network nodes.

[0141] The input and output information may be stored in a specific location (for example, memory) or may be managed using a management table. The input and output information may be overwritten, updated, or added to. The output information may be deleted. The input information may be sent to another device.

[0142] The determination may be made based on a value represented by one bit (0 or 1), a Boolean value (true or false), or a numerical comparison (e.g., comparison with a predetermined value).

[0143] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. Furthermore, notification of predetermined information (e.g., notification that "X is true") is not limited to being done explicitly, but may be done implicitly (e.g., by not notifying the predetermined information).

[0144] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0145] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of transmission media.

[0146] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0147] Note that terms explained 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 a channel and a symbol may be a signal (signaling). Furthermore, a signal may be a message. Furthermore, a component carrier (CC) may be called a carrier frequency, a cell, a frequency carrier, etc.

[0148] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0149] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information. For example, a radio resource may be indicated by an index.

[0150] The names used for the above-described parameters are not intended to be limiting in any way. Furthermore, the mathematical expressions using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (e.g., PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not intended to be limiting in any way.

[0151] In this disclosure, terms such as "base station (BS)," "radio base station," "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.

[0152] A base station can accommodate one or more (e.g., three) cells (also called sectors). When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be divided into multiple smaller areas, and each smaller area can be provided with communication services by a base station subsystem (e.g., a small indoor base station (Remote Radio Head: RRH)).

[0153] The terms "cell" or "sector" refer to part or all of the coverage area of ​​a base station and / or base station subsystem that provides communication services within that coverage area.

[0154] In the present disclosure, the base station transmitting information to a terminal may be interpreted as the base station instructing the terminal to control or operate based on the information.

[0155] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0156] 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 some other suitable terminology.

[0157] 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 object, or the mobile object itself. The mobile object may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile object (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 also include devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

[0158] Furthermore, a base station in the present disclosure may be interpreted as a mobile station (user terminal, the same applies hereinafter). For example, the aspects / embodiments of the present disclosure may be applied to a configuration in which communication between a base station and a mobile station is replaced with communication between multiple mobile stations (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the mobile station may be configured to have the functions of a base station. Furthermore, terms such as "uplink" and "downlink" may be interpreted as terms corresponding to communication between terminals (for example, "side"). For example, terms such as an uplink channel and a downlink channel may be interpreted as a side channel (or side link).

[0159] Similarly, a mobile station in the present disclosure may be interpreted as a base station, in which case the base station may have the functions of a mobile station.

[0160] A radio frame may be composed of one or more frames in the time domain. Each of the one or more frames in the time domain may be called a subframe. A subframe may further be composed 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.

[0161] Numerology may be a communication parameter applied to at least one of transmission and reception of a signal or channel, such as subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame structure, specific filtering operations performed by a transceiver in the frequency domain, and specific windowing operations performed by a transceiver in the time domain.

[0162] A slot may consist of one or more symbols in the time domain (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol, a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol, etc.) A slot may be a numerology-based time unit.

[0163] A slot may include multiple minislots. Each minislot may consist of one or more symbols in the time domain. A minislot may also be called a subslot. A minislot 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.

[0164] The radio frame, subframe, slot, minislot, and symbol all represent time units for transmitting signals, and may be referred to by other names corresponding to the radio frame, subframe, slot, minislot, and symbol.

[0165] 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 minislot may be called a TTI. That is, at least one of the subframe and the 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, minislot, etc., instead of a subframe.

[0166] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) to each user terminal in TTI units. However, the definition of TTI is not limited to this.

[0167] The TTI may be a transmission time unit for a channel-encoded data packet (transport block), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) to which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

[0168] When one slot or one minislot is called a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit for scheduling. Also, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0169] A TTI having a time length of 1 ms may be called a regular TTI (TTI in LTE Rel. 8-12), normal TTI, long TTI, regular subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a regular TTI may be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

[0170] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and equal to or greater than 1 ms.

[0171] A resource block (RB) is a resource allocation unit in the time domain and frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of numerology, for example, 12. The number of subcarriers included in an RB may also be determined based on numerology.

[0172] The time domain of an RB may include one or more symbols and may be one slot, one minislot, one subframe, or one TTI in length. Each TTI, subframe, etc. may be composed of one or more resource blocks.

[0173] Note that one or more RBs may also be called a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, or the like.

[0174] Furthermore, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource region of one subcarrier and one symbol.

[0175] A Bandwidth Part (BWP) (which may also be referred to as a fractional bandwidth) may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a common reference point of the carrier. PRBs may be defined in a given BWP and numbered within that BWP.

[0176] The BWP may include a BWP for UL (UL BWP) and a BWP for DL ​​(DL BWP). One or more BWPs may be configured for a UE within one carrier.

[0177] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal / channel outside the active BWP. Note that the terms "cell," "carrier," etc. in this disclosure may be read as "BWP."

[0178] The above-described structures of the radio frame, subframe, slot, minislot, and symbol are merely examples. For example, the number of subframes included in a radio frame, the number of slots per subframe or radio 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, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP) length, and other configurations can be changed in various ways.

[0179] The terms "connected," "coupled," or any variation thereof, refer to 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" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access." As used in this disclosure, two elements may be considered to be "connected" or "coupled" to each other using one or more wires, cables, and / or printed electrical connections, as well as electromagnetic energy having wavelengths in the radio frequency range, microwave range, and optical (both visible and invisible) range, as some non-limiting and non-exhaustive examples.

[0180] The reference signal may also be abbreviated as Reference Signal (RS), and may also be called a pilot depending on the applicable standard.

[0181] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0182] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0183] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed therein or that the first element must precede the second element in some way.

[0184] When used in this disclosure, the terms "include," "including," and variations thereof are intended to be inclusive, similar to the term "comprising." Furthermore, when used in this disclosure, the term "or" is not intended to be an exclusive or.

[0185] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0186] As used in this disclosure, the terms "determining" and "determining" may encompass a wide variety of actions. "Determining" and "determining" may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiring (e.g., searching in a table, database, or other data structure), ascertaining, and the like. "Determining" and "determining" may also include receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), and the like. Furthermore, "judgment" and "decision" can include regarding resolving, selecting, choosing, establishing, comparing, etc. as having been "judged" or "decided." In other words, "judgment" and "decision" can include regarding some action as having been "judged" or "decided." Furthermore, "judgment (decision)" can be interpreted as "assuming," "expecting," "considering," etc.

[0187] In the present 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 "coupled" may also be interpreted in the same way as "different."

[0188] Although the present disclosure has been described in detail above, it is 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 spirit and scope of the present disclosure as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not have any limiting meaning on the present disclosure. [Explanation of symbols]

[0189] 10. Wireless communication systems 50 wireless base stations 51 Radio Section 100 Ground GW equipment 110 Radio Department 120 Duplexer 130 Frequency conversion unit 140 Multiplexer / Demultiplexer 150 Radio transmitter / receiver 160 Multiplexing and Demultiplexing Unit 170 Digital Processing Unit 200 Relay Station Equipment 300 UE 1001 processor 1002 memory 1003 Storage 1004 Communication equipment 1005 Input Device 1006 Output Device 1007 Bus

Claims

1. a receiving unit for receiving signals from terrestrial network facilities of multiple telecommunications carriers via the same type of connection interface; a frequency conversion unit that applies a frequency shift for each of the plurality of communication carriers to radio frequencies carrying signals of the plurality of communication carriers to convert the radio frequencies into frequencies that are located within a predetermined frequency band on a link to a relay station device of a non-terrestrial network; a transmitter for transmitting a frequency-converted radio signal to the relay station device; A ground station device comprising:

2. A wireless communication system including a base station of a first communication carrier and a ground station device connected to the base station via a first type of connection interface, The base station a transmitter that transmits a first signal of a first communications carrier and a second signal received from a terrestrial network facility of a second communications carrier via a second type of connection interface to the terrestrial station device via the first type of connection interface; The ground station device a receiving unit that receives a first signal and a second signal via the first type connection interface; a frequency conversion unit that applies a frequency shift for each of the communication carriers to radio frequencies carrying the first signal and the second signal to convert the radio frequencies into frequencies located within a predetermined frequency band on a link to a relay station device of a non-terrestrial network; a transmitter for transmitting a frequency-converted radio signal to the relay station device; A wireless communication system comprising:

3. a receiving unit that receives signals from a plurality of communication carriers that are allocated at predetermined intervals within a frequency band of a first link to a terminal of a relay station device of a non-terrestrial network; a frequency conversion unit that applies a frequency shift to radio frequencies carrying signals of the plurality of communication carriers to convert, for each beam applied on the first link, the frequencies of the plurality of communication carriers within the beam into frequencies arranged at the predetermined intervals; a transmitter that transmits a frequency-converted radio signal on a second link to the relay station device; A ground station device comprising:

4. The ground station device according to claim 3 , wherein the frequency conversion unit applies a frequency shift that reduces gaps between the frequencies of the plurality of communication carriers that are arranged at the predetermined intervals.

5. a receiving unit that receives signals from a plurality of communication carriers that are allocated in a predetermined arrangement within a frequency band of a first link to a terminal of a relay station device of a non-terrestrial network; a frequency conversion unit that applies a frequency shift to radio frequencies carrying signals of the plurality of communication carriers to convert the frequencies of the plurality of beams applied on the first link for each of the communication carriers into arranged frequencies; a transmitter that transmits a frequency-converted radio signal on a second link to the relay station device; A ground station device comprising:

6. receiving signals from a plurality of communication carriers allocated at predetermined intervals within a frequency band of a first link to a terminal of a relay station device of a non-terrestrial network; applying a frequency shift to radio frequencies carrying signals of each of the plurality of carriers to convert the frequencies of the plurality of carriers to the predetermined intervals within the beam for each beam applied on the first link; transmitting the frequency-converted radio signal over a second link to the relay station device; A communication method for a ground station device comprising:

7. receiving signals from a plurality of communication carriers allocated in a predetermined arrangement within a frequency band of a first link to a terminal of a relay station device of a non-terrestrial network; applying a frequency shift to radio frequencies carrying signals of each of the plurality of communication operators to convert the frequencies of the plurality of beams applied on the first link for each of the communication operators into contiguous frequencies; transmitting the frequency-converted radio signal over a second link to the relay station device; A communication method for a ground station device comprising:

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