JP2022158451A - Radio relay device, communication system, method for controlling radio relay device, and program - Google Patents

Abstract

To achieve lower consumption of a power amplifier without affecting data communication in a radio relay device for relaying communication between a base station and a terminal device.SOLUTION: A radio relay device 10 including a power amplifier 110 amplifying a downlink transmission signal transmitted to a UE acquires information of a downlink transmission stop pattern for stopping a transmission signal in a plurality of slots constituting a downlink radio frame, detects a frame timing of the downlink radio frame, and controls a bias applied to the power amplifier 110 about a time zone of a slot which stops the downlink transmission signal on the basis of the information of the downlink transmission stop pattern and detection results of the frame timing.SELECTED DRAWING: Figure 1

Description

The present invention relates to a radio relay device, a communication system, a control method for a radio relay device, and a program for relaying communication between a base station and a terminal device.

2. Description of the Related Art Conventionally, a radio communication system is known that controls the power consumption of a power amplifier in a base station. In Patent Document 1, in a radio communication system using an orthogonal frequency division multiple access method, scheduling information regarding radio resources is confirmed, and the presence or absence of symbols to which user data is not allocated is determined using the confirmation result. , when there are symbols to which no user data is assigned, a method is disclosed in which the bias applied to the power amplifier is turned off in the symbol interval to which no user data is assigned. According to this method, the base station controls the bias of the power amplifier to be turned off during symbol periods in which there is no user data, so that the power consumption of the power amplifier of the base station can be optimized. there is

Japanese Patent Application Laid-Open No. 2018-019428

However, when the above method is applied to a wireless relay device that is installed away from the base station and relays communication between the base station and the terminal device and control is performed to turn off the bias of the power amplifier in the symbol interval, the following is performed. there is a problem. That is, due to the transmission delay between the base station and the radio repeater, which are separated from each other, it is difficult to transmit and share the information of the symbol period in which the transmission signal is generated to the radio repeater in real time and at high speed. In particular, in the case of a radio repeater that stays in the air, the distance to the base station increases and the transmission delay increases, making it more difficult to share information on symbol intervals in which transmission signals are generated in real time and at high speed. . Unless the information in the symbol interval in which the transmission signal is generated cannot be shared in real time and at high speed, it is impossible to accurately control the bias of the power amplifier to be turned off in the symbol interval in the above method. Therefore, it is not possible to reduce the power consumption of the power amplifier of the wireless relay apparatus without affecting data communication.

A radio relay device according to one aspect of the present invention is a radio relay device that relays communication between a base station device and a terminal device. This radio relay apparatus includes a first power amplifier that amplifies a downlink transmission signal to be transmitted to the terminal device, a second power amplifier that amplifies an uplink transmission signal to be transmitted to the base station device, and a downlink an information acquisition unit for acquiring information on a downlink transmission stop pattern for stopping transmission signals in a plurality of slots constituting a link radio frame; a frame timing detection unit for detecting frame timing of the downlink radio frame; a control unit for controlling a bias applied to the first power amplifier for a time slot of a slot in which the downlink transmission signal is stopped based on downlink transmission stop pattern information and the detection result of the frame timing; Prepare.

In the radio relay device, the information acquisition unit acquires information on an uplink transmission stop pattern for stopping transmission signals in a plurality of slots constituting an uplink radio frame; and the control unit records the slot time zone in which the uplink transmission signal is stopped based on the information of the uplink transmission stop pattern and the detection result of the frame timing. A bias applied to the second power amplifier may be controlled.

In the radio relay device, the information acquisition unit may acquire the transmission stop pattern information from a server that centrally manages scheduling information of a plurality of base station devices or from a base station that has the function of the server.

In the radio repeater, the first power amplifier performs a first power amplification operation in which power is consumed when there is no input or when a small signal is input, and the first power amplification operation consumes power when there is no input or when a small signal is input. and a second power amplification operation that is smaller than the first power, and the control unit sets the first power so that the second power amplification operation is performed for a slot time period in which the downlink transmission signal is stopped. The bias applied to the amplifier may be changed.

Further, in the radio repeater, the second power amplifier has a first power amplification operation that consumes power when there is no input or when a small signal is input, and the power consumption when there is no input or when a small signal is input is the first power. and a second power amplification operation that is smaller than the amplification operation, and the control unit performs the second power amplification operation so as to perform the second power amplification operation for a time slot in which the uplink transmission signal is stopped. , the bias applied to the power amplifier may be changed.

Here, the first power amplifying operation may be a class A or class AB power amplifying operation, and the second power amplifying operation may be a class C or class B power amplifying operation.

In the radio relay device, the frame timing detection unit may detect the frame timing of the radio frame based on a synchronization signal included in the radio signal received from the base station device, or may detect the frame timing of the radio frame. The frame timing of the radio frame may be detected based on time information received from a satellite and an estimation result of a propagation delay amount in a feeder link that relays communication between the base station device and the terminal device. .

In the radio relay device, the information on the downlink transmission stop pattern and the information on the uplink transmission stop pattern may be determined based on data traffic information in the cell formed by the radio relay device and its peripheral cells. Alternatively, the information on the downlink transmission stop pattern and the information on the uplink transmission stop pattern are determined based on location information of the wireless relay device or information on footprints of cells formed by the wireless relay device. may be

In the radio relay apparatus, the transmission stop pattern information may be multiplexed with a feeder link signal for relaying communication between the base station apparatus and the terminal apparatus and transmitted from the base station apparatus.

In the radio relay device, the information on the transmission stop pattern is transmitted from the base station device via a communication line separate from a feeder link that relays communication between the base station device and the terminal device. good too.

In the radio relay device, relaying communication between the base station device and a terminal device located in a plurality of sector cells, the information acquisition unit acquires information on the transmission stop pattern for each sector cell, The frame timing detection unit may detect the frame timing of the radio frame for each sector cell, and the first power amplifier, the second power amplifier, and the control unit may be provided for each sector cell. .

The radio relay device may be mounted on a floating object or flying object located in the sky, and may form a wide-area cell toward an area including a cell of a ground base station.

A communication system according to another aspect of the present invention includes any one of the radio relay apparatuses and the base station apparatus.

The communication system may further include a server that centrally manages scheduling information of a plurality of base station apparatuses and transmits information on the transmission stop pattern to the radio relay apparatus based on the scheduling information.

In the communication system, the base station apparatus multiplexes information of the transmission stop pattern into a feeder link signal that relays communication between the base station apparatus and the terminal apparatus, and transmits the information to the radio relay apparatus. good too.

A control method according to still another aspect of the present invention includes a first power amplifier that amplifies a downlink transmission signal to be transmitted to a terminal device, and a second power amplifier that amplifies an uplink transmission signal to be transmitted to a base station device. and a power amplifier, and a control method for a radio relay apparatus that relays communication between the base station apparatus and the terminal apparatus. This control method includes acquiring information of a downlink transmission stop pattern for stopping transmission signals in a plurality of slots constituting a downlink radio frame, detecting frame timing of the downlink radio frame, controlling the bias to be applied to the first power amplifier for a time zone of a slot in which the downlink transmission signal is stopped based on the downlink transmission stop pattern information and the frame timing detection result; including.

In the control method of the radio relay apparatus, acquiring information of an uplink transmission stop pattern for stopping transmission signals in a plurality of slots constituting an uplink radio frame, and detecting frame timing of the uplink radio frame. and controlling the bias to be applied to the second power amplifier for the slot time zone in which the uplink transmission signal is stopped based on the information on the uplink transmission stop pattern and the detection result of the frame timing. may include doing and

A program according to still another aspect of the present invention includes a first power amplifier that amplifies a downlink transmission signal to be transmitted to a terminal device, and a second power amplifier that amplifies an uplink transmission signal to be transmitted to a base station device. A program executed in a computer or processor provided in a wireless relay device that has an amplifier and relays communication between the base station device and the terminal device. This program includes a program code for acquiring information of a downlink transmission stop pattern for stopping transmission signals in a plurality of slots constituting a downlink radio frame, and a frame timing of the downlink radio frame. the bias to be applied to the first power amplifier for the slot time zone in which the downlink transmission signal is to be stopped based on the program code of, the information on the downlink transmission stop pattern, and the detection result of the frame timing program code for controlling;

In the program, a program code for acquiring information of an uplink transmission stop pattern for stopping transmission signals in a plurality of slots constituting an uplink radio frame, and for detecting frame timing of the uplink radio frame. bias to be applied to the second power amplifier for a time zone of a slot in which the uplink transmission signal is stopped based on the program code of, the information of the uplink transmission stop pattern, and the detection result of the frame timing and program code for controlling.

According to the present invention, it is possible to reduce the power consumption of a power amplifier in a wireless relay device that relays communication between a base station and a terminal device without affecting data communication.

1 is an explanatory diagram showing an example of a main configuration of a communication system including a radio relay device according to an embodiment; FIG. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram showing an example of an overall configuration of a communication system having a hierarchical cell configuration including radio relay apparatuses according to an embodiment; FIG. 4 is an explanatory diagram showing another example of the overall configuration of a communication system with a hierarchical cell configuration including the radio relay apparatus according to the embodiment; FIG. 4 is an explanatory diagram showing an example of unnecessary transmitter noise when data transmission of a wireless relay device is stopped in the communication system according to the embodiment; FIG. 2 is an explanatory diagram showing an example of downlink and uplink radio frames in the communication system according to the embodiment; FIG. 4 is an explanatory diagram showing an example of bias control for turning off the power amplification function of the power amplifier of the radio repeater in the communication system of FIGS. 2 and 3; FIG. 4 is an explanatory diagram showing an example of a synchronization method for detecting frame timing in the wireless relay device 10 according to the embodiment; FIG. 4 is an explanatory diagram showing a frame timing error ΔT in another example of a synchronization method for detecting frame timing in the radio relay apparatus 10 according to the embodiment; 1 is a block diagram showing a configuration example of a portion corresponding to a downlink of a radio relay apparatus in a communication system according to an embodiment; FIG. FIG. 4 is a block diagram showing another configuration example of a portion corresponding to the downlink of the radio relay apparatus in the communication system according to the embodiment;

Embodiments of the present invention will be described below with reference to the drawings. Here, the embodiments of the present invention will be described on the premise of application to a 3GPP LTE/LTE-Advanced mobile communication system and a next-generation NR (New Radio) mobile communication system after the fifth generation. The concept of the present invention can be applied to any system as long as it uses a cell configuration and a physical channel configuration.

The radio relay apparatus according to the embodiment described in this document shares the frequency band of the service link with the terrestrial cell of the terrestrial base station, and forms a large cell that overlaps with the terrestrial cell of the terrestrial base station. It is a wireless relay device. The radio relay apparatus of this embodiment detects the frame timing of the radio frame of the relay signal relayed between the ground base station apparatus and the terminal apparatus (UE), and semi-static scheduling information ( For example, a transmission stop pattern that specifies slots for stopping transmission signals is obtained. The radio relay apparatus of this embodiment controls the bias of the power amplifier (amplifier) of the service link based on the frame timing and the semi-static scheduling information, and controls the bias of the power amplifier (amplifier) of the service link, and the time period that does not include the data signal for the terminal equipment (UE). By turning off the power amplification function of the amplifier (power amplifier) for (for example, a specific slot), it is possible to reduce the power consumption of the power amplifier (amplifier) during non-data transmission when the data signal of the service link is not transmitted. In both cases, the amplification and radiation of unnecessary noise signals during non-data transmission can be reduced to suppress interference with terrestrial cells.

FIG. 1 is an explanatory diagram showing an example of the main configuration of a communication system (radio relay system) including a radio relay device 10 according to this embodiment. In FIG. 1, the communication system includes an airborne radio relay device 10 provided in an air vehicle (eg, airship, solar plane, drone, etc.) 15 that flies in the sky. The radio relay device 10 is a repeater-type relay station, and performs radio communication with the HAPS base station device 35 on the ground via the feeder link FL, and radio communication with the terminal device (UE) 60 via the service link SL. , relays communication between the HAPS base station device 35 and the terminal device (UE) 60 . The radio repeater 10 includes a power amplifier (PA) 110 as a first power amplifier that amplifies the transmission signal of the service link SL, and a power amplifier (PA) 110 as a second power amplifier that amplifies the transmission signal of the feeder link FL. ) 120. In addition, the communication system (radio relay system) may include the HAPS base station device 35 in addition to the radio relay device 10 and may further include the UE 60 .

The frequency (frequency band) of the feeder link FL and the frequency (frequency band) of the service link SL may be different frequencies (frequency bands) in order to prevent interference due to radio wave interference.

The radio relay device 10 has a function of detecting a synchronization signal included in a downlink radio frequency (RF) signal received from the HAPS base station device 35 via the feeder link FL, and detects a downlink signal to be relayed (hereinafter referred to as Also referred to as a “downlink signal”) frame timing can be detected. Also, the radio relay apparatus 10 receives downlink semi-static scheduling information or downlink and uplink semi-static scheduling information from the HAPS base station apparatus 35 or the central control server.

The semi-static scheduling information is information that can specify whether or not each slot includes data to be transmitted for a plurality of slots constituting a radio frame. This is information on the transmission stop pattern. This semi-static scheduling information indicates whether or not data is included for each of a plurality of symbols assigned to a plurality of resource elements (REs) constituting a radio frame (symbols to be transmitted or symbols not to be transmitted). It is not the normal scheduling information that you specify. The semi-static scheduling information is not information that changes for each radio frame, but is changed periodically or irregularly in units of a plurality of radio frames.

The wireless relay device 10 receives the detection result of the frame timing autonomously detected based on the synchronization signal received from the HAPS base station device 35, and the downlink semi-static scheduling information received and acquired from the HAPS base station device 35. Based on this, the power amplifier 110 is instructed to temporarily stop the power amplification function of the power amplifier 110 instead of stopping (turning off) the power supply to the power amplifier 110 for slots that do not contain data to be transmitted. Bias control is performed to turn off the applied bias.

In the communication system of FIG. 1, the frame timing is not detected based on the synchronization signal received from the HAPS base station device 35, but is detected from satellites of GNSS (global navigation satellite system) such as GPS (Global Positioning System). The frame timing may be detected based on the time information of . In this case, the radio relay device 10 and the HAPS base station device 35 each include a GNSS receiver that receives radio waves from the GNSS satellites, and for example, the internal clock is periodically set based on the absolute time information output from the GNSS receiver. , and the frame timing may be detected based on the output signal of the internal clock after correction and the preset start timing of the radio frame.

FIG. 2 is an explanatory diagram showing an example of the overall configuration of a communication system having a hierarchical cell configuration including the radio relay apparatus according to this embodiment. In FIG. 2, as a countermeasure against communication traffic due to disasters and extraordinary events, the antenna 102 of a flying object 15 such as an airship, a solar plane, and a drone, which is a floating object that can move in the sky, is connected to the ground or water (for example, A plurality of service links SL(1), SL(2) of the mobile communication network formed toward the sea) are deployed in wide-area large cells 10A(1), 10A(2). The plurality of large cells 10A(1) and 10A(2) are formed by a single radio repeater and are also called "sector cells". Inside the large cell 10A, a mobile communication network cell (hereinafter referred to as "terrestrial 20A(1) and 20A(2) exist.

Note that FIG. 2 shows an example of a hierarchical cell configuration in which cells overlap each other such that a plurality of ground cells 20(1)A and 20(2)A are included in a large cell 10(1)A. However, a cell configuration in which a portion of the large cell 10(1)A and at least a portion of the plurality of ground cells 20(1)A and 20(2)A may overlap each other.

In the example of FIG. 2, an airship-type HAPS (“High Altitude Platform Station” or “High Altitude Pseudo-satellite”) as a flying object capable of moving in the sky is shown as an airship-type aircraft 15 having the radio relay device 10. However, the flying object 15 may be a drone, balloon, aircraft, helicopter, solar plane type HAPS or LAPS ("low altitude platform station" or "low altitude pseudosatellite") capable of moving or flying over the sky, airship type LAPS. , other unmanned or manned air vehicles such as satellites. In addition, the flying object 15 is controlled so that after moving to a predetermined position in the sky where radio relay is to be performed, it stays at that position or circulates within a predetermined range of flight space including that position. may

An aircraft is positioned by flying in an airspace at an altitude of 100 km or less above the ground, sea surface, or water surface such as a river or lake, under autonomous control, external control, or operation by an operator on board the aircraft. may be controlled as follows. Also, the flight airspace of the flying object may be a stratospheric airspace with an altitude of 11 [km] or more and 50 [km] or less. Furthermore, the flight airspace of the aircraft may be an airspace at an altitude of 15 [km] or more and 25 [km] or less where weather conditions are relatively stable, and in particular an airspace at an altitude of approximately 20 [km]. good too.

In FIG. 2, a plurality of large cells 10A(1), 10A(2) and a plurality of ground cells 20A(1), 20A(2) are operated in the same frequency band. For example, the terrestrial cells 20(1)A and 20(2)A use the large cells 10(1)A and 10(2)A for radio communication with a terminal device (hereinafter also referred to as "UE") which is a mobile station. is a same-frequency cell (for example, a macrocell or a small cell) in which the same frequency (frequency band) A as is used. UEs 61(1) and 61(2) in FIG. 1 are located in large cells 10A(1) and 10A(2), respectively, and are connected to the cells 10A(1) and 10A(2). UEs 62(1) and 62(2) in FIG. 2 are located in ground cells 20A(1) and 20A(2), respectively, and are connected to the cells 20A(1) and 20A(2). .

The mobile communication system of the present embodiment is a communication system conforming to next-generation standard specifications such as LTE (Long Term Evolution) / LTE-Advanced or 5th generation, and the radio relay device 10 includes a plurality of large cells 10A ( 1), antennas 101 of service links SL(1), SL(2) forming 10A(2), and HAPS base station equipment (e.g., eNodeB, gNodeB) 35 provided on the ground side for wireless communication. and an antenna 102 of the feeder link FL. The HAPS base station device 35 is connected to the HAPS core network 30 of the mobile communication network via a communication line such as a line terminating device and a dedicated line, and provides a predetermined communication interface with various nodes such as core network devices and servers. communication is enabled by

Terrestrial base stations (eg, eNodeB, gNodeB) 20(1), 20(2) are, for example, macro cell base stations or small cell base stations. A macrocell base station is a high-output base station that covers a terrestrial cell, which is usually installed outdoors in a mobile communication network and covers a wide area with a radius of several hundred meters to several kilometers. Unlike wide-area macrocell base stations, small cell base stations have a wireless communication range of several meters to several hundred meters, and have a low output that can be installed inside buildings such as general homes, stores, and offices. is the base station of Each macro cell base station or small cell base station is connected to another base station, for example, by a wired communication line, and can communicate with a predetermined communication interface. In addition, the macro cell base station or small cell base station is connected to the terrestrial core network 40 of the mobile communication network via communication lines such as line termination equipment and dedicated lines, and is connected to various nodes such as core network equipment and servers. can communicate with each other through a predetermined communication interface.

The HAPS core network 30 and the terrestrial core network 40 include the HAPS base station devices 35 of the large cells 10A(1) and 10A(2) and the terrestrial base stations 20(1) of the terrestrial cells 20A(1) and 20A(2). , 20(2). Further, the frequencies commonly used in the cells 10A(1), 10A(2) 20A(1), 20A(2) may be, for example, frequencies in the microwave band of 300 MHz to 30 GHz, or millimeter waves higher than 30 GHz. It may be a band frequency.

In this embodiment, the radio relay device 10 mounted on the aircraft 15 moves through the HAPS base station device 35 to which the antenna 102 and the gateway (GW) station, which is the feeder link relay device on the ground side, are connected. It can communicate with the HAPS core network 30 of the communication network, various core network devices, external networks such as the Internet, various servers such as the central control server 50, and the like.

The central control server 50 centrally manages base station information such as scheduling information of the HAPS base station device 35 and the terrestrial base stations 20(1) and 20(2), and generates control information for controlling the base stations. can be done. The central control server 50 also has a function of managing semi-static scheduling information used for bias control of the power amplifier 110 (120) of the radio relay device 10 and notifying the radio relay device 10 of the semi-static scheduling information. . The central control server 50 may be installed in a remote location such as a data center, or may be installed in the HAPS core network 30 or the terrestrial core network 40 .

When UEs 61(1) and 61(2) are located in large cells 10A(1) and 10A(2), respectively, UEs 61(1) and 61(2) are connected to HAPS base stations via radio relay devices 10 in the sky corresponding to the cells in which they are located. It is possible to wirelessly communicate with the device 35 using a predetermined communication method and wireless communication resources. Further, when the UEs 62(1) and 63(2) are located in the terrestrial cells 20A(1) and 20A(2), respectively, the terrestrial base stations 20(1) and 20(2) corresponding to the located cells 2) can wirelessly communicate with each other using a predetermined communication scheme and wireless communication resources. UEs 61(1), 61(2) and UEs 62(1), 62(2) are respectively configured using hardware such as a computer device having a CPU, memory, etc., and a wireless communication unit, and execute a predetermined program. As a result, communication with the HAPS base station device 35 via the radio relay device 10 and radio communication with the terrestrial base stations 20(1) and 20(2) can be performed.

The HAPS base station device 35 is configured using hardware such as a computer device having a CPU, memory, etc., an external communication interface unit for the HAPS core network 30, an external communication interface unit for the central control server 50, a wireless communication unit, etc. By executing a predetermined program, wireless communication with UEs 61(1) and 61(2) is performed using a predetermined communication method and wireless communication resources, and communication with the core network device of the HAPS core network 30 is performed. It is possible to transmit and receive information between them, and to transmit and receive information to and from the central control server 50 .

Each of the terrestrial base stations 20(1) and 20(2) is configured using hardware such as a computer device having a CPU, memory, etc., an external communication interface section for the terrestrial core network 40, and a radio communication section. By executing the program, wireless communication with UEs 62(1) and 62(2) is performed using a predetermined communication method and wireless communication resources, and communication with the core network device of the terrestrial core network 40 is performed. Information can be sent and received, and information can be sent and received to and from the central control server 50 .

The wireless relay device 10 is configured using hardware such as a computer device having a CPU, a memory, etc., and a wireless communication unit for a service link and a feeder link. Wireless communication with UEs 62(1) and 62(2) can be performed using wireless communication resources, and information can be transmitted/received to/from central control server 50 via HAPS base station device 35. can.

By executing a predetermined program, the radio relay device 10 performs processing for detecting the frame timing of radio frames based on the synchronization signal included in the radio signal received from the HAPS base station device 35, or detects the frame timing of the radio frame. The bias of power amplifiers 110 (120) may be controlled based on semi-static scheduling information received from device 35 or central control server 50, and so on.

The HAPS base station apparatus 35 and the terrestrial base stations 20(1) and 20(2) are base station apparatuses capable of downlink wireless communication with UEs using an OFDM (orthogonal frequency division multiplexing) system. Each base station apparatus 35, 20(1), 20(2) includes, for example, an antenna, a radio signal path switching unit, a duplexer (DUP: Duplexer), a downlink radio reception unit, and an OFDM as a downlink modulation unit ( Orthogonal Frequency Division Multiplexing) modulator, controller, uplink radio receiver and uplink demodulator (for example, SC-FDMA (Single-Carrier Frequency-Division Multiple Access) demodulator or OFDM demodulator). Additionally, each base station device 35, 20(1), 20(2) may comprise a downlink radio transmitter and an OFDM demodulator for special applications such as air interface based synchronization.

The SC-FDMA demodulation section performs SC-FDMA demodulation processing on the received signal received by the uplink radio reception section, and passes the demodulated data to the control section. The OFDM demodulation unit performs OFDM demodulation processing on the reception signal received by the uplink radio reception unit, and passes the demodulated data to the control unit. The OFDM modulation unit modulates the data of the downlink signal received from the control unit and transmitted to the UE located in the cell of the own station using the OFDM method so that the data is transmitted with a predetermined power. Further, when the base station receives, for example, information about a slot to stop transmission from the server, the OFDM modulation section is controlled to stop downlink transmission only for a specific slot in the radio frame. The downlink radio transmission section transmits the transmission signal modulated by the OFDM modulation section via the duplexer, the radio signal path switching section and the antenna.

In the mobile communication system of the present embodiment, as shown in FIG. 3, a radio relay device 10 in the sky and ground base stations 20(1) and 20(2) each receive radio waves from GNSS satellites such as GPS. The GNSS receiver 103 may be provided, the internal clock may be corrected based on the absolute time information output from the GNSS receiver 103, and time synchronization may be performed with each other. In this case, the radio relay device 10, based on the absolute time information and the clock signal of the internal clock corrected based on the absolute time information from the GNSS receiver 103, the ground base stations 20 (1), 20 (2) and It is possible to detect the frame timing of radio frames synchronized between.

In the mobile communication system with the hierarchical cell configuration illustrated in FIGS. Noise (see Figure 4) is an issue. In order to reduce power consumption and suppress transmitter noise, a conventional method of controlling the bias applied to the power amplifier is applied, and symbols to which no user data is assigned are controlled in each slot constituting the radio frame of the cell. If there is a symbol to which user data is not assigned, the bias applied to the power amplifier is turned off in the symbol section to which user data is not assigned.

However, in the method applying the conventional bias control method, due to the transmission delay between the HAPS base station device 35 and the radio relay device 10 which are separated from each other, the information of the symbol interval generated by the transmission signal can be obtained in real time and at high speed. It is difficult to transmit to the wireless relay device 10 and share it immediately. In particular, in the case of the radio relay apparatus 10 that stays in the air, the distance to the base station apparatus increases and the transmission delay increases. it gets harder. Unless the information in the symbol interval in which the transmission signal is generated cannot be shared in real time and at high speed, it is impossible to accurately control the power amplifier 110 (120) to turn off the bias in the symbol interval in the above method. Therefore, it is not possible to reduce the power consumption of the power amplifier 110 (120) of the wireless relay device 10 without affecting data communication, and it is not possible to suppress transmitter noise.

Therefore, in the present embodiment, attention is paid to interference avoidance using radio resource allocation control by time division in radio frames, which is one of frequency sharing methods in a hierarchical cell configuration, and the radio relay apparatus 10 detects the frame timing of radio frames. At the same time, the radio relay device 10 and the HAPS base station device 35 share information on a transmission stop pattern for stopping transmission signals for avoiding interference in a plurality of slots forming a radio frame, and stop the transmission signals. The bias applied to the power amplifier 110 (120) of the radio repeater 10 is controlled so as to reduce the power consumption of the power amplifier 110 (120) in the slot time zone.

For example, in the example of FIG. 5, in the downlink radio frame 910, the downlink transmission stop pattern is preset so as not to allocate data in the 2nd, 3rd, 7th, and 8th slots. The transmitted signal is stopped. Also, in the uplink radio frame 920, an uplink transmission stop pattern is set in advance so as not to allocate data in the second and fifth slots, so the transmission signal in these slots is stopped. In this way, since the downlink transmission stop pattern and the uplink transmission stop pattern are determined and set in advance, the time period (slot position) in which bias control is performed so as to turn off the power amplification function of the power amplifier 110 (120) ) is known.

FIG. 6 is an explanatory diagram showing an example of bias control for turning off the power amplification function of the power amplifier 110 of the radio repeater 10 in the communication system of FIGS. In FIG. 6, in order to avoid interference with the center slot to be protected in the radio frames 921 and 922 of the terrestrial cells 20(1)A and 20(2)A, the frame timing of each cell is synchronized. , data is not assigned to the corresponding center slot of the large cell 10A(1), and the bias applied to the power amplifier 110 is turned off to stop the power amplification function. This makes it possible to avoid interference from the large cell 10A(1) to the terrestrial cells 20(1)A and 20(2)A in the time slot of the slot and to suppress transmitter noise radiation. In the communication system of FIGS. 2 and 3, since there is no terrestrial cell under the control of the second large cell 10A(2), the radio frame of the large cell 10A(2) may always be transmitted.

The information on the downlink transmission stop pattern and the information on the uplink transmission stop pattern described above are all managed and grasped by the HAPS base station device 35 or the central control server 50 . Therefore, the radio relay device 10 can acquire downlink transmission stop pattern information and uplink transmission stop pattern information from the HAPS base station device 35 or the central control server 50 as semi-static scheduling information.

In the radio relay apparatus 10, in order to control the bias of the power amplifier 110 (120) based on semi-static scheduling information (downlink transmission stop pattern information and uplink transmission stop pattern information), Timing must be specified.

In the communication system of FIG. 2, the radio relay device 10 detects the frame timing based on the synchronization signal placed at a predetermined position in the radio frame received from the HAPS base station device 35, and identifies the timing of the beginning of the radio frame. be able to.

Further, in the communication system of FIG. 3, the radio relay device 10 and the base station device 35 each include a GNSS receiver that receives radio waves from GNSS satellites. For example, based on the absolute time information output from the GNSS receiver, By periodically correcting the internal clock, the radio relay device 10 and the base station device 35 are in a state of time synchronization with each other. The radio relay apparatus 10 can detect the frame timing based on the corrected output signal of the internal clock and the preset start timing of the radio frame, and can specify the start timing of the radio frame.

2 and 3, the central control server 50 distributes semi-static scheduling information to the ground base stations 20(1), 20(2) and the radio relay device 10. FIG.

The HAPS base station device 35 schedules wireless communication of service links and feeder links according to the scheduling information received from the HAPS core network 30 . Also, the HAPS base station device 35 reports the location information of the radio relay device 10 and the footprint information of the large cells 10A(1) and 10A(2) by GNSS to the central control server 50 .

Each of the terrestrial base stations 20(1) and 20(2) implements scheduling of wireless communication on service links and feeder links according to scheduling information received from the terrestrial core network 40. FIG. Also, each of the ground base stations 20(1) and 20(2) reports received power (interference power) from other cells (mainly large cells 10A(1) and 10A(2)) to the central control server 50. .

The radio repeater 10 detects the frame timing of the relay signal, and controls the bias of the power amplifier (amplifier) for each cell according to the aforementioned semi-static scheduling information and the like.

The NW device of HAPS core network 30 reports data traffic information of each of large cells 10A(1) and 10A(2) to central control server 50 . The NW device of the terrestrial core network 40 reports data traffic information of each of the terrestrial cells 20A(1) and 20A(2) to the central control server 50. FIG.

The central control server 50 can centrally manage semi-static scheduling information of the HAPS base station device 35 and the terrestrial base stations 20(1) and 20(2). For example, in LTE-Release 10 of 3GPP, in a heterogeneous network in which large cell base stations and small cell base stations coexist, physical shared channel (PDSCH) or physical control channel (PDCCH) transmission of large cell base stations is stopped. There is a mechanism of eICIC (enhanced Inter-Cell Interference Coordination) that avoids inter-cell interference by using an ABS (Almost Blank Subframe) pattern indicating the position of the cell. The ABS pattern is 40-bit bitmap information, and this ABS pattern is used as transmission stop pattern information for semi-static scheduling information, and sent to the HAPS base station device 35 and the ground base station 20 (1) via the central control server 50 and the like. , 20(2). The HAPS base station device 35 and the terrestrial base stations 20(1) and 20(2) perform semi-static scheduling control in cooperation with each other based on the ABS pattern included in the semi-static scheduling information, so that the large cell 10A Interference avoidance control on the time axis between (1) and the ground cells 20A(1) and 20A(2) can be performed.

The method of distributing semi-static scheduling information by the central control server 50 in this embodiment can utilize such an eICIC mechanism, but is not necessarily limited to this method.

In addition, the central control server 50 receives the location information of the radio relay device 10 from the HAPS base station device 35, the footprint information of the large cells 10A(1) and 10A(2), the terrestrial base stations 20(1) and 20( 2) Received power (interference power) from other cells (mainly large cells 10A (1) and 10A (2)) received from, and received from each NW device of HAPS core network 30 and terrestrial core network 40 Based on at least one piece of data traffic information, update the semi-static scheduling information including the information on the downlink transmission stop pattern and the information on the uplink transmission stop pattern, and update the semi-static scheduling information on the ground. It may be distributed to the base stations 20 ( 1 ), 20 ( 2 ) and the radio relay device 10 .

For example, when the moving distance of the position of the wireless relay device 10 is greater than a predetermined threshold (distance), or when the moving distance of the footprints of the large cells 10A(1) and 10A(2) becomes greater than a predetermined threshold (distance), the downlink transmission stop pattern information, the uplink transmission stop pattern information, or both in the semi-static scheduling information described above may be updated.

In this embodiment, as exemplified in FIGS. 2 and 3, the radio repeater 10 relays signals of multiple large cells 10A(1) and 10A(2) such that they form separate footprints. can be controlled to In that case, the radio relay device 10 may be configured with semi-static scheduling for the large cells 10A(1) and 10A(2). For example, when the radio relay device 10 forms the footprints of the large cells 10A(1) and 10A(2) (see FIGS. 2 and 3), the footprint of the first large cell 10A(1) includes If there are other terrestrial base stations 20(1), 20(2) that can interfere and there are no other terrestrial base stations that can interfere within the footprint of the second large cell 10A(2) , the first large cell 10A(1) is given quasi-static scheduling information with fixed transmission stop times (slots), while the second large cell 10A(2) is given all the time Semi-static scheduling information that does not require transmission to be stopped in (slot) may be distributed.

Whether or not there is another terrestrial base station that may cause interference within the footprint is determined, for example, by the radiation pattern information of the antenna 101 mounted on the radio relay device 10, the radio relay device 10 and other terrestrial base stations. can be estimated based on the location information of

Further, when the radio relay device 10 is a flying radio relay device mounted on a flying object such as a drone, the position changes from time to time. Based on the route information and the radiation pattern information of the antenna 101, one or more pieces of footprint information are estimated by the central control server 50, and the semi-static scheduling information is updated at regular intervals based on the footprint information. and may be distributed.

Further, the central control server 50 determines that the reception power (interference power) received by the ground base stations 20(1) and 20(2) from the large cells 10A(1) and 10A(2) is greater than a predetermined threshold. From time to time, the downlink transmission stop pattern information, the uplink transmission stop pattern information, or both in the aforementioned semi-static scheduling information may be updated.

The interference levels from the large cells 10A(1), 10A(2) in the ground cells 20A(1), 20A(2) can be measured, for example, as follows. In a standard UE conforming to LTE of 3GPP, in RRC (Radio Resource Control) Connected state, MR (Measurement Report) can be transmitted when event conditions specified by the base station are satisfied. The MR allows the UE to report measurement results such as RSRP (Reference Signal Received Power) from the cell in which it is currently serving and other cells to the base station and the network. The terrestrial base stations 20(1) and 20(2) of the present embodiment use the above MR from UEs located in their own areas to report interference signal power mainly from the radio relay apparatus 10, and central control It can report to server 50 .

In addition, when the data traffic information received from each NW device of the HAPS core network 30 and the terrestrial core network 40 exceeds a predetermined threshold, the central control server 50 performs downlink transmission in the semi-static scheduling information described above. Information on the stop pattern, information on the uplink transmission stop pattern, or both may be updated.

2 and 3, the HAPS base station device 35 may have the function of the central control server 50 without providing the central control server 50. FIG.

FIG. 7 is an explanatory diagram showing an example of a synchronization method for detecting frame timing in the wireless relay device 10 according to this embodiment. In order to detect frame timing, the radio relay device 10 can use a method of detecting a synchronization signal included in an RF signal (radio signal), which is a downlink relay signal received from the HAPS base station device 35 . The radio repeater 10 has an RF signal receiving mechanism (radio interface-based synchronizing device) and can hold arbitrary RF signal waveform data. The radio relay apparatus 10 holds a replica of the synchronization signal expected to be transmitted from the HAPS base station apparatus 35, and performs time correlation processing on the received RF signal using the replica signal. Detect the peak position of the correlation value and identify the frame timing.

In FIG. 7, the radio relay apparatus 10 receives both PSS 915(1) and SSS 915(2) as the synchronization signal 915 of the HAPS base station apparatus 35 and performs time synchronization processing. In FIG. 7, the radio relay apparatus 10 receives a synchronization signal 915 in which PSS 915(1) and SSS 915(2) are consecutive from the HAPS base station apparatus 35 including the CP at a predetermined timing. Further, the radio relay device 10 generates a combined replica sequence 916 in which the PSS replica 916(1) and the SSS replica 916(2) each including the CP are continuous. A correlation value 971 between the received signal of the synchronization signal (SSS, PSS) 915 and the combined replica sequence 916 is calculated while sliding this combined replica sequence 916 with reference to a predetermined time of the internal clock. A peak 971p of is detected. The time of the internal clock at which the correlation value peak 971p is detected is stored as the frame timing (the time of the rear end of the synchronization signal 915) Ts. After that, the transmission timing of each radio frame (starting time of each radio frame) until the next time synchronization processing (frame timing detection processing) is performed is set based on the frame timing Ts.

In the example of FIG. 7, since the length of the combined replica sequence 916 used when calculating the correlation is approximately twice the length of the PSS replica, the noise is less than that of the correlation value 972 when only the PSS is used. , and the correlation detection characteristics when detecting the correlation value peak (frame timing Ts) are approximately doubled. Therefore, the precision of the frame timing Ts of the replica becomes higher.

When a GNSS receiver such as a GPS receiver is installed in the wireless relay device 10, it is possible to obtain UTC (Coordinated Universal Time) time as absolute time. Therefore, the radio relay device 10 corrects the clock signal of the internal clock so as to synchronize with the UTC time output from the GNSS receiver, and the specific UTC time and frame timing (for example, the start timing of the radio frame, or , the start timing of a slot with a specific slot number in a radio frame), and correcting the propagation delay estimated from the position information of the HAPS base station device 35 and the aircraft 15, the radio relay device 10 performs the HAPS Frame timing can be specified and detected autonomously without using a synchronization signal from the base station apparatus 35 .

If there is a propagation delay due to a difference in distance between the radio relay device 10 and the relay source base station (HAPS base station device 35) installed on the ground, it is specified by the UTC time of the radio relay device 10. An error (ΔT in FIG. 8) may occur between the received radio frame 911 and the frame timing of the radio frame 912 of the signal actually received from the relay source base station (HAPS base station device 35). This error is determined by the central control server 50 estimating the amount of propagation delay using the location information of the radio relay device 10 and the location information of the relay source base station (HAPS base station device 35), and 10 can be corrected.

FIG. 9 is a block diagram showing a configuration example of a portion corresponding to the downlink of the radio relay apparatus 10 in the communication system according to the embodiment. Note that the HAPS base station device 35 in the figure is in a state in which the frame timings of radio frames during transmission are synchronized with the terrestrial base stations 20(1) and 20(2). This synchronization of the frame timing of the radio frames depends on the propagation delay due to the distance between the center of the large cell 10A(1) on the ground and the antenna 101 of the radio repeater 10, the ground cells 20A(1), 20A(2) and the base station. 20(1) and 20(2), the propagation delay due to the distance from the antennas 20(1) and 20(2) is taken into account, and corrections are made so that radio frames with the same frame number (SFN: system frame number) reach the ground at approximately the same timing. may

9, the radio relay apparatus 10 includes a service link antenna 101, a feeder link antenna 102, a feeder link side duplexer unit 111, a power amplifier (LNA) 112 for the feeder link received signal, and a feeder link received signal. a filter unit 113 for, a frequency conversion unit 114 that performs frequency conversion processing between the frequency of the feeder link FL and the frequency of the service link SL, a filter unit 115 for the service link transmission signal, and an FET that amplifies the service link transmission signal A power amplifier (PA) 110 composed of (field effect transistor), etc., a duplexer unit 116 on the service link side, an internal clock 117 and a frame detection control unit 118, and a bias for controlling the bias applied to the power amplifier (PA) 110 and a control unit 119 .

The frame detection control unit 118 uses the clock signal of the internal clock 117 as a reference, and based on the synchronization signal included in the relay signal received from the HAPS base station device 35, the downlink frame timing (for example, the time at the beginning of the radio frame). information, or head time information of a slot of a predetermined number including a synchronization signal), and outputs the detection result to the bias control section 119 .

In addition, frame detection control section 118 demodulates and decodes semi-static scheduling information including downlink transmission stop pattern information multiplexed on the relay signal branched from filter section 115, extracts the extracted semi-static It passes the scheduling information to the bias control unit 119 .

The bias control unit 119 generates a downlink transmission signal based on the detection result of the downlink frame timing output from the frame detection control unit 118 and information on the downlink transmission stop pattern included in the semi-static scheduling information. The bias applied to the power amplifier 110 is controlled so as to reduce the power consumption of the power amplifier 110 for the time period of the slot in which the power is stopped.

For example, a first power amplification operation in which the power amplifier 110 consumes power when there is no input or when a small signal is input, and a second power amplification operation in which power consumption when there is no input or when a small signal is input is smaller than that of the first power amplification operation. , the bias control unit 119 controls the bias applied to the power amplifier 110 so as to perform the second power amplification operation for the time period of the slot in which the downlink transmission signal is stopped. . Here, the first power amplifying operation may be a class A or class AB power amplifying operation, and the second power amplifying operation may be a class C or class B power amplifying operation.

Further, when the power amplifier 110 is composed of an FET (Field Effect Transistor), the bias control section 119 operates the power amplifier 110 in class A operation during the slot time period for transmitting the downlink transmission signal. A predetermined gate bias voltage is applied to the power amplifier 110 by turning on the bias as shown in FIG. On the other hand, for the time period of the slot in which the downlink transmission signal is stopped, the bias control section 119 turns off the bias so as to operate the power amplifier 110 in class C operation, which consumes less power than class A operation. Stop applying the gate bias voltage to the amplifier 110 .

In FIG. 9 , semi-static scheduling information including downlink transmission stop pattern information is delivered from the central control server 50 to the baseband processing unit 352 of the HAPS base station device 35 . The baseband processing unit 352 of the HAPS base station device 35 uses the clock signal of the internal clock 154 as a reference by the scheduler unit 353 to generate a relay signal in a predetermined radio frame based on the data to be transmitted, and the antenna 351 is operated. to the wireless relay device 10 via the A synchronization signal is placed in the radio frame of the relay signal, and semi-static scheduling information is multiplexed.

In FIG. 9, the central control server 50 communicates with an external line transmitting/receiving unit (for example, a satellite communication module, WiFi module, other mobile communication module) 55 and antenna 551 to the wireless relay device 10 . The bias control unit 119 of the radio repeater 10 connects the antenna 121 and an external line transmission/reception unit (for example, , satellite communication module, WiFi module, and other mobile communication modules) 120 from the central control server 50 .

FIG. 10 is a block diagram showing another configuration example of the portion corresponding to the downlink of the radio relay apparatus in the communication system according to the embodiment. 10, the description of the same configuration as in FIG. 9 is omitted.

In FIG. 10, the radio relay device 10 includes a GNSS receiver 130 that receives radio waves from GNSS satellites via an antenna 131 and outputs the aforementioned UTC time. The clock signal of the internal clock 117 is corrected so as to synchronize with the UTC time output from the GNSS receiver 130 . Based on the clock signal of the internal clock 117, the frame detection control unit 118 detects a specific UTC time and frame timing (for example, the start timing of a radio frame or the start of a specific slot number in a radio frame) as described above. timing) and correcting the propagation delay estimated from the position information of the HAPS base station device 35 and the aircraft 15, the frame timing can be autonomously adjusted without using the synchronization signal from the HAPS base station device 35. Can be identified and detected.

10, the HAPS base station device 35 includes a GNSS receiver 356 that receives radio waves from GNSS satellites via an antenna 355 and outputs the aforementioned UTC time. The clock signal of the internal clock 354 is corrected so as to synchronize with the UTC time output from the GNSS receiver 356 . Based on the clock signal of the internal clock 354, the baseband processing unit 352 uses a specific UTC time and frame timing (for example, the start timing of a radio frame or the start of a specific slot number in a radio frame) as described above. timing), it is possible to set the frame timing of the wireless frame at the time of transmission.

9 and 10, the frame detection control unit 118 of the radio relay apparatus 10 generates semi-static scheduling information including downlink transmission stop pattern information for stopping transmission signals in a plurality of slots constituting a downlink radio frame. and a frame timing detector that detects the frame timing of downlink radio frames. Also, based on the downlink transmission stop pattern information and the detection result of the frame timing, the bias control unit 119 reduces the power consumption of the power amplifier 110 in the slot time period during which the downlink transmission signal is stopped. It functions as a first controller that controls the bias applied to the power amplifier 110 .

Also, the configuration of the radio relay apparatus 10 illustrated in FIGS. 9 and 10 is provided for each of the large cells 10A(1) and 10A(2), which are a plurality of sector cells. semi-static scheduling information including downlink transmission stop pattern information is acquired for each sector cell), and the frame timing of the downlink radio frame is detected. Also, the bias control unit 119 may perform bias control on the power amplifier 110 described above for each large cell (sector cell).

As described above, according to the present embodiment, low power consumption of the power amplifier (PA) 110 during non-data transmission in which no data signal is transmitted on the service link SL in the wireless relay device 10 located in the sky is achieved. It is possible to suppress interference with the ground cells 20A(1) and 20A(2) by reducing unnecessary noise signal radiation from the radio relay device 10 during data transmission.

In addition, in the above embodiment, the case of applying to the downlink of the service link SL in which the RF signal is transmitted from the radio relay device 10 to the UE on the ground has been mainly described, but the present invention can be applied from the radio relay device 10 to the downlink. The same can be applied to the uplink of the feeder link FL through which RF signals are transmitted toward the HAPS base station device 35 . In this case, the radio relay apparatus 10 includes an information acquisition unit that acquires information on an uplink transmission stop pattern for stopping transmission signals in a plurality of slots that form an uplink radio frame, and detects the frame timing of the uplink radio frame. The power consumption of the power amplifier (PA) 120 is reduced for the time period of the slot in which the uplink transmission signal is stopped based on the frame timing detector, the information on the uplink transmission stop pattern, and the detection result of the frame timing. and a second controller that controls the bias applied to the power amplifier (PA) 120 . In the case of the uplink of this feeder link FL, the power amplifier (PA) 120 at the time of non-data transmission in which the data signal of the feeder link FL is not transmitted in the wireless relay device 10 located in the sky is reduced, Unnecessary noise signal radiation from the wireless relay device 10 during non-data transmission can be reduced. The frame timing of the uplink radio frame can be detected as follows. For example, the downlink and uplink frame timings of the HAPS base station apparatus 35 are synchronized with each other, and those frame timings are synchronized with the downlink and uplink frame timings of the terrestrial base stations 20(1) and 20(2). on the premise that the frame timing detection unit detects the downlink frame timing based on the synchronization signal included in the downlink radio signal from the HAPS base station device 35, and then detects the downlink frame timing. The frame timing of the uplink radio frame may be indirectly detected by determining the uplink frame timing so as to match.

Also, the processing steps and components of communication systems, mobile communication systems, base stations, base station devices, radio relay devices and terminal devices (user devices, mobile stations) described herein may be implemented by various means. be able to. For example, these processes and components may be implemented in hardware, firmware, software, or any combination thereof.

For hardware implementation, means such as processing units used to implement the above steps and components in an entity (e.g., various wireless communication devices, Node Bs, terminals, hard disk drives, or optical disk drives) are: One or more of an application specific integrated circuit (ASIC), digital signal processor (DSP), digital signal processor (DSPD), programmable logic device (PLD), field programmable gate array (FPGA), processor , controllers, microcontrollers, microprocessors, electronic devices, other electronic units designed to perform the functions described herein, computers, or combinations thereof.

Also, for firmware and/or software implementations, means such as processing units used to implement the above components may be programs (e.g., procedures, functions, modules, instructions) that perform the functions described herein. , etc.). In general, any computer/processor readable medium tangibly embodying firmware and/or software code means, such as a processing unit, used to implement the above steps and components described herein. may be used to implement For example, firmware and/or software code may be stored in memory and executed by a computer or processor, such as in a controller. The memory may be implemented within the computer or processor, or external to the processor. The firmware and/or software code may also be, for example, random access memory (RAM), read only memory (ROM), non-volatile random access memory (NVRAM), programmable read only memory (PROM), electrically erasable PROM (EEPROM). ), flash memory, floppy disk, compact disk (CD), digital versatile disk (DVD), magnetic or optical data storage devices, etc. good. The code may be executed by one or more computers or processors and may cause the computers or processors to perform certain aspects of the functionality described herein.

Also, the medium may be a non-temporary recording medium. Also, the code of the program is not limited to a specific format as long as it can be read and executed by a computer, processor, or other device or machine. For example, the program code may be source code, object code, or binary code, or may be a mixture of two or more of these codes.

Moreover, the description of the embodiments disclosed herein is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to this disclosure will be readily apparent to those skilled in the art, and the general principles defined herein are applicable to other variations without departing from the spirit or scope of this disclosure. This disclosure, therefore, is not to be limited to the examples and designs described herein, but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

10: Radio relay device 10A(1), 10A(2): Large cell (sector cell)
15: Aircraft 20: Ground Base Stations 20A(1), 20A(2): Ground Cell 30: HAPS Core Network 35: HAPS Base Station Device 40: Ground Core Network 50: Central Control Server 55: External Line Transmission/Reception Unit 101: Antenna 102 : Antenna 103 : GNSS receiver 110 : Power amplifier 111 : Duplexer unit 113 : Filter unit 114 : Frequency conversion unit 115 : Filter unit 116 : Duplexer unit 117 : Internal clock 118 : Frame detection control unit 119 : Bias control unit 121 : Antenna 130 : GNSS receiver 131 : Antenna 154 : Internal clock 351 : Antenna 352 : Baseband processor 353 : Scheduler 354 : Internal clock 355 : Antenna 356 : GNSS receiver 551 : Antenna

Claims (21)

A wireless relay device that relays communication between a base station device and a terminal device,
a first power amplifier that amplifies a downlink transmission signal to be transmitted to the terminal device;
a second power amplifier that amplifies an uplink transmission signal to be transmitted to the base station apparatus;
an information acquisition unit that acquires information on a downlink transmission stop pattern that stops transmission signals in a plurality of slots that constitute a downlink radio frame;
a frame timing detection unit that detects frame timing of the downlink radio frame;
a control unit for controlling a bias applied to the first power amplifier for a slot time zone in which the downlink transmission signal is stopped, based on the downlink transmission stop pattern information and the frame timing detection result; ,
A radio relay device comprising: In the wireless relay device of claim 1,
The information acquisition unit acquires information on an uplink transmission stop pattern for stopping transmission signals in a plurality of slots constituting an uplink radio frame,
The frame timing detection unit detects frame timing of the uplink radio frame,
Based on the uplink transmission stop pattern information and the frame timing detection result, the control unit adjusts the bias to be applied to the second power amplifier for the slot time zone in which the uplink transmission signal is stopped. A radio relay device characterized by: In the radio relay device according to claim 1 or 2,
The radio relay apparatus, wherein the information acquisition unit acquires the information on the transmission stop pattern from a server that centrally manages scheduling information of a plurality of base station apparatuses or from a base station that has the function of the server. In the wireless relay device of claim 1,
The first power amplifier has a first power amplification operation that consumes power when there is no input or a small signal input, and a second power that consumes less power than the first power amplification operation when there is no input or a small signal input. configured to be switchable between amplification operation and
The control unit changes the bias applied to the first power amplifier so that the second power amplification operation is performed in the time slot of the slot in which the downlink transmission signal is stopped,
A wireless relay device characterized by: In the wireless relay device of claim 2,
The second power amplifier has a first power amplification operation that consumes power when there is no input or when a small signal is input, and a second power that consumes less power than the first power amplification operation when there is no input or when a small signal is input. configured to be switchable between amplification operation and
The control unit changes the bias applied to the second power amplifier so that the second power amplification operation is performed for the time slot of the slot in which the uplink transmission signal is stopped.
A wireless relay device characterized by: In the radio relay device according to claim 4 or 5,
The first power amplification operation is a class A or class AB power amplification operation,
The radio repeater according to claim 1, wherein the second power amplification operation is a class C or class B power amplification operation. In the wireless relay device according to any one of claims 1 to 6,
The radio relay apparatus, wherein the frame timing detector detects the frame timing of the radio frame based on a synchronization signal included in the radio signal received from the base station apparatus. In the wireless relay device according to any one of claims 1 to 6,
The frame timing detection unit, based on time information received from a GNSS satellite and an estimation result of a propagation delay amount in a feeder link that relays communication between the base station device and the terminal device, the downlink 1. A radio relay apparatus, characterized in that it detects frame timing of a link radio frame and said uplink radio frame. In the wireless relay device according to any one of claims 1 to 8,
A radio relay device, wherein the information on the transmission stop pattern is determined based on data traffic information in a cell formed by the radio relay device and cells in the periphery thereof. In the wireless relay device according to any one of claims 1 to 8,
The wireless relay device, wherein the information of the transmission stop pattern is determined based on the location information of the wireless relay device or the footprint information of the cell formed by the wireless relay device. In the wireless relay device according to any one of claims 1 to 10,
The radio relay apparatus, wherein the information on the transmission stop pattern is multiplexed with a feeder link signal that relays communication between the base station apparatus and the terminal apparatus and is transmitted from the base station apparatus. . In the wireless relay device according to any one of claims 1 to 10,
The transmission stop pattern information is transmitted from the base station device via a communication line separate from a feeder link that relays communication between the base station device and the terminal device. wireless repeater. In the wireless relay device according to any one of claims 1 to 12,
The radio relay device relays communication between the base station device and terminal devices located in a plurality of sector cells,
The information acquisition unit acquires information on the transmission stop pattern for each sector cell,
The frame timing detection unit detects frame timing of the radio frame for each sector cell,
A radio relay apparatus according to claim 1, wherein said first power amplifier, said second power amplifier and said control unit are provided for each of said sector cells. In the wireless relay device according to any one of claims 1 to 13,
A radio relay device, wherein the radio relay device is mounted on a floating body or a flying object located in the sky, and forms a wide-area cell toward an area including a cell of a ground base station. A communication system comprising the radio relay apparatus according to any one of claims 1 to 14 and a base station apparatus. 16. In the communication system of claim 15,
A communication system, comprising: a server that centrally manages scheduling information of a plurality of base station apparatuses and transmits information of the transmission stop pattern to the radio relay apparatus based on the scheduling information. In the communication system according to claim 15 or 16,
The base station apparatus multiplexes the information on the transmission stop pattern into a feeder link signal that relays communication between the base station apparatus and the terminal apparatus, and transmits the information to the radio relay apparatus. Communications system. a first power amplifier that amplifies a downlink transmission signal to be transmitted to a terminal device; and a second power amplifier that amplifies an uplink transmission signal to be transmitted to a base station device; A control method for a wireless relay device that relays communication with a terminal device,
Acquiring information on a downlink transmission stop pattern for stopping transmission signals in a plurality of slots constituting a downlink radio frame;
detecting frame timing of the downlink radio frame;
controlling the bias to be applied to the first power amplifier for a time slot of a slot in which the downlink transmission signal is stopped, based on the downlink transmission stop pattern information and the frame timing detection result;
A control method for a wireless relay device, comprising: In the method for controlling a wireless relay device according to claim 18,
Acquiring information on an uplink transmission stop pattern for stopping transmission signals in a plurality of slots constituting an uplink radio frame;
detecting frame timing of the uplink radio frame;
controlling the bias to be applied to the second power amplifier for a slot time zone in which the uplink transmission signal is stopped based on the information of the uplink transmission stop pattern and the detection result of the frame timing;
A control method for a wireless relay device, comprising: a first power amplifier that amplifies a downlink transmission signal to be transmitted to a terminal device; and a second power amplifier that amplifies an uplink transmission signal to be transmitted to a base station device; A program executed in a computer or processor provided in a wireless relay device that relays communication with a terminal device,
A program code for acquiring information on a downlink transmission stop pattern for stopping transmission signals in a plurality of subframes constituting a downlink radio frame;
a program code for detecting frame timing of the downlink radio frame;
A program for controlling a bias to be applied to the first power amplifier for a slot time zone in which the downlink transmission signal is stopped, based on the downlink transmission stop pattern information and the frame timing detection result. code and
A program characterized by comprising: In the program of claim 20,
A program code for acquiring information on an uplink transmission stop pattern for stopping transmission signals in a plurality of slots constituting an uplink radio frame;
a program code for detecting frame timing of the uplink radio frame;
A program for controlling a bias to be applied to the second power amplifier for a slot time zone in which the uplink transmission signal is stopped, based on the information on the uplink transmission stop pattern and the detection result of the frame timing. code and
A program characterized by comprising:

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