Communication device, method, and non-transitory computer-readable storage medium for identifying spoofing signal

Abstract

The communication device may comprise: a transceiver; a receiver; a memory storing instructions; and at least one processor including a processing circuit. The instructions, when executed individually or collectively by the at least one processor, may instruct the communication device to: obtain reference coordinate information of satellites on the basis of first location information of the communication device, time synchronization information, and orbit information of the satellites; obtain coordinate information of a target satellite among the satellites on the basis of a received target GNSS signal; determine whether the target GNSS signal is a normal signal or a spoofing signal, on the basis of the reference coordinate information and the coordinate information; calculate second location information of the communication device by using the target GNSS signal according to the determination that the target GNSS signal is the normal signal; and refrain from calculating the second location information by using the target GNSS signal according to the determination that the target GNSS signal is the spoofing signal.

Description

Communication device, method, and non-transient computer-readable storage medium for identifying spoofing signals

[0001] The present disclosure relates to a communication device, a method, and a non-transient computer-readable storage medium for identifying spoofing signals.

[0002] A communication device can receive signals from a satellite. Depending on the signal, the communication device may use GNSS (global navigation satellite system) technology to obtain location information, speed information, and time information of the communication device. GNSS can be referred to as a navigation system that provides location information, speed information, and time information of the communication device using signals transmitted from a satellite.

[0003] The information described above may be provided as related art for the purpose of aiding understanding of the present disclosure. No claim or determination is made as to whether any of the foregoing may be applied as prior art related to the present disclosure.

[0004] A communication device is provided. The communication device may include a transceiver for communicating with a terrestrial network element (NE). The communication device may include a receiver configured to receive a global navigation satellite system (GNSS) signal. The communication device may include a memory comprising one or more storage media for storing instructions. The communication device may include at least one processor comprising a processing circuitry. When the instructions are executed individually or collectively by the at least one processor, the communication device may cause the communication device to obtain reference coordinate information of the satellites based on a first location information of the communication device, time synchronization information obtained using the transceiver, and orbit information of the satellites obtained using the transceiver. When the instructions are executed individually or collectively by the at least one processor, the communication device may cause the communication device to obtain coordinate information of a target satellite among the satellites indicated by the target GNSS signal based on a target GNSS signal received using the receiver. When the above instructions are executed individually or collectively by the at least one processor, the communication device may be caused to determine whether the target GNSS signal is a normal signal transmitted from the target satellite or a spoofing signal not transmitted from the target satellite, based on the reference coordinate information and the coordinate information.When the above instructions are executed individually or collectively by the at least one processor, they may cause the communication device to calculate a second position information of the communication device using the target GNSS signal based on the determination that the target GNSS signal is the normal signal. When the above instructions are executed individually or collectively by the at least one processor, they may cause the communication device to refrain from calculating the second position information of the communication device using the target GNSS signal based on the determination that the target GNSS signal is the spoofing signal.

[0005] A method is provided. The method may be performed in a communication device having a transceiver for communicating with a terrestrial network element (NE) and a receiver configured to receive a global navigation satellite system (GNSS) signal. The method may include an operation of obtaining reference coordinate information of the satellites based on first location information of the communication device, time synchronization information obtained using the transceiver, and orbit information of the satellites obtained using the transceiver. The method may include an operation of obtaining coordinate information of a target satellite among the satellites that is indicated by the target GNSS signal based on a target GNSS signal received using the receiver. The method may include an operation of determining whether the target GNSS signal is a normal signal transmitted from the target satellite or a spoofing signal not transmitted from the target satellite, based on the reference coordinate information and the coordinate information. The method may include an operation of calculating second location information of the communication device using the target GNSS signal according to the determination that the target GNSS signal is the normal signal. The above method may include an operation of refraining from calculating the second position information of the communication device using the target GNSS signal based on the determination that the target GNSS signal is the spoofing signal.

[0006] A non-transient computer-readable storage medium is provided. The non-transient computer-readable storage medium may store one or more programs. The one or more programs may include instructions that cause the communication device to obtain reference coordinate information of said satellites based on a first position information of said communication device, time synchronization information obtained using said transceiver, and orbit information of said satellites obtained using said transceiver, when executed by the communication device having a transceiver for communicating with a terrestrial network element (NE) and a receiver configured to receive a global navigation satellite system (GNSS) signal. The one or more programs may include instructions that cause the communication device to obtain coordinate information of a target satellite indicated by said target GNSS signal among said satellites based on a target GNSS signal received using said receiver when executed by the communication device. The above one or more programs may include instructions that cause the communication device to determine, based on the reference coordinate information and the coordinate information, whether the target GNSS signal is a normal signal transmitted from the target satellite or a spoofing signal not transmitted from the target satellite, when executed by the communication device. The above one or more programs may include instructions that cause the communication device to calculate second position information of the communication device using the target GNSS signal, based on the determination that the target GNSS signal is the normal signal, when executed by the communication device.The above one or more programs may include instructions that cause the communication device to refrain from calculating the second position information of the communication device using the target GNSS signal when executed by the communication device, upon determination that the target GNSS signal is the spoofing signal.

[0007] Figure 1 illustrates an example of a wireless communication system.

[0008] Figure 2 illustrates an example of an interface between an upper network node and a lower network node.

[0009] Figure 3 illustrates an example of the functional configuration of a network node.

[0010] FIG. 4 illustrates an example of a communication device that receives GNSS (global navigation satellite system) signals.

[0011] FIG. 5 illustrates examples of operations of a communication device that determines whether a GNSS signal is a spoofing signal or a normal signal.

[0012] FIG. 6 illustrates examples of operations of a communication device for obtaining reference position coordinates of satellites.

[0013] Figure 7a illustrates an example of converting LLH (latitude longitude height) coordinates to ECEF (earth centered, earth fixed) coordinates.

[0014] FIG. 7b illustrates an example of obtaining the satellite's reference ENU (east-north-up) coordinates.

[0015] FIG. 7c illustrates an example of obtaining the reference azimuth and reference elevation angle of a satellite.

[0016] Throughout the drawings, the same reference numerals will be understood to refer to the same parts, components, and structures.

[0017] The terms used in this disclosure are used merely to describe specific embodiments and are not intended to limit the scope of other embodiments. A singular expression may include a plural expression unless the context clearly indicates otherwise. Terms used herein, including technical or scientific terms, may have the same meaning as generally understood by those skilled in the art described in this disclosure. Terms used in this disclosure that are defined in a general dictionary may be interpreted as having the same or similar meaning as they have in the context of the relevant technology, and are not to be interpreted in an ideal or overly formal sense unless explicitly defined in this disclosure. In some cases, even terms defined in this disclosure are not to be interpreted to exclude the embodiments of this disclosure.

[0018] In the various embodiments of the present disclosure described below, a hardware-based approach is described as an example. However, since the various embodiments of the present disclosure include techniques using both hardware and software, the various embodiments of the present disclosure do not exclude a software-based approach.

[0019] Terms used in the following description to refer to data (e.g., data, information, time synchronization information, location information, orbital information, reference coordinate information, coordinate information), terms referring to values ​​(e.g., reference distance, reference time), terms for operation states (e.g., operation, process), terms referring to objects, terms referring to network entities (e.g., terrestrial NE), terms referring to components of a device, etc., are examples provided for the convenience of explanation. Accordingly, the present disclosure is not limited to the terms described below, and other terms having equivalent technical meanings may be used. Additionally, terms such as '...part', '...device', '...object', '...body' used below may refer to at least one shape structure or a unit that processes a function.

[0020] Additionally, in this disclosure, expressions of "greater than" or "less than" may be used to determine whether a specific condition is satisfied or fulfilled; however, this is merely for the purpose of expressing an example and does not exclude descriptions of "greater than" or "less than." Conditions described as "greater than" may be replaced with "greater than," conditions described as "less than" may be replaced with "less than," and conditions described as "greater than and less than" may be replaced with "greater than and less than." Furthermore, "A" to "B" below refer to at least one of elements from A (including A) to B (including B). Below, "C" and / or "D" refers to including at least one of "C" or "D," i.e., {"C", "D", "C" and "D"}.

[0021] This disclosure describes various embodiments using terms used in some communication standards (e.g., 3GPP (3rd Generation Partnership Project), ETSI (European Telecommunications Standards Institute), xRAN (extensible radio access network), O-RAN (open-radio access network), but these are merely illustrative examples. Various embodiments of this disclosure can be easily modified and applied to other communication systems.

[0022] Figure 1 illustrates an example of a wireless communication system.

[0023] Referring to FIG. 1, FIG. 1 illustrates a base station (110) and a terminal (120) as part of nodes using a wireless channel in a wireless communication system. FIG. 1 illustrates only one base station, but the wireless communication system may include other base stations identical or similar to the base station (110).

[0024] A base station (110) is a network infrastructure that provides wireless access to a terminal (120). The base station (110) has coverage defined based on the distance over which it can transmit signals. In addition to being a base station, the base station (110) may be referred to as an 'access point (AP)', 'eNodeB (eNB)', '5G node (5th generation node)', 'next generation nodeB (gNB)', 'wireless point', 'transmission / reception point (TRP)', or other terms having an equivalent technical meaning.

[0025] A terminal (120) is a device used by a user and communicates with a base station (110) via a wireless channel. The link from the base station (110) to the terminal (120) is referred to as a downlink (DL), and the link from the terminal (120) to the base station (110) is referred to as an uplink (UL). Additionally, although not shown in FIG. 1, the terminal (120) and another terminal can communicate with each other via a wireless channel. In this case, the link between the terminal (120) and another terminal (device-to-device link, D2D) is referred to as a sidelink, and the sidelink may be used interchangeably with the PC5 interface. In some other embodiments, the terminal (120) may be operated without user involvement. According to one embodiment, the terminal (120) is a device that performs machine type communication (MTC) and may not be carried by the user. Additionally, according to one embodiment, the terminal (120) may be a narrowband (NB)-Internet of Things (IoT) device.

[0026] The terminal (120) may be referred to as 'user equipment (UE)', 'customer premises equipment (CPE)', 'mobile station', 'subscriber station', 'remote terminal', 'wireless terminal', 'electronic device', or 'user device' or other terms having an equivalent technical meaning.

[0027] The base station (110) can perform beamforming with the terminal (120). The base station (110) and the terminal (120) can transmit and receive wireless signals in a relatively low frequency band (e.g., FR 1 (frequency range 1) of NR). Additionally, the base station (110) and the terminal (120) can transmit and receive wireless signals in a relatively high frequency band (e.g., FR 2 (or FR 2-1, FR 2-2, FR 2-3), FR 3) of NR) and a millimeter wave (mmWave) band (e.g., 28 GHz, 30 GHz, 38 GHz, 60 GHz)). To improve channel gain, the base station (110) and the terminal (120) can perform beamforming. Here, beamforming may include transmit beamforming and receive beamforming. The base station (110) and the terminal (120) can impart directivity to the transmitted signal or the received signal. To this end, the base station (110) and the terminal (120) can select serving beams through a beam search or beam management procedure. After the serving beams are selected, subsequent communication can be performed through a resource that is in a quasi-co-located (QCL) relationship with the resource that transmitted the serving beams.

[0028] If large-scale characteristics of the channel that transmitted the symbol on the first antenna port can be inferred from the channel that transmitted the symbol on the second antenna port, the first antenna port and the second antenna port can be evaluated as being in a QCL relationship. For example, the large-scale characteristics may include at least one of a delay spread, a Doppler spread, a Doppler shift, an average gain, an average delay, and a spatial receiver parameter.

[0029] In FIG. 1, it is described that both the base station (110) and the terminal (120) perform beamforming, but the embodiments of the present disclosure are not necessarily limited thereto. In some embodiments, the terminal may or may not perform beamforming. Also, the base station may or may not perform beamforming. That is, either the base station or the terminal may perform beamforming, or neither the base station nor the terminal may perform beamforming.

[0030] In the present disclosure, a beam refers to a spatial flow of a signal in a wireless channel, formed by one or more antennas (or antenna elements), and this formation process may be referred to as beamforming. Beamforming may include at least one of analog beamforming or digital beamforming (e.g., precoding). A reference signal transmitted based on beamforming may include, for example, a demodulation-reference signal (DM-RS), a channel state information-reference signal (CSI-RS), a synchronization signal / physical broadcast channel (SS / PBCH), or a sounding reference signal (SRS). Additionally, an IE such as a CSI-RS resource or an SRS-resource may be used as a configuration for each reference signal, and such a configuration may include information associated with the beam. Information associated with a beam may refer to whether the configuration (e.g., CSI-RS resource) uses the same spatial domain filter as other configurations (e.g., other CSI-RS resources within the same CSI-RS resource set) or a different spatial domain filter, or which reference signal it is QCLed with, and if so, what type (e.g., QCL type A, B, C, D).

[0031] Conventionally, in communication systems with a relatively large cell radius of base stations, each base station was installed to include the functions of a digital processing unit (or DU (distributed unit)) and an RF (radio frequency) processing unit (RF processing unit, or RU (radio unit)). However, as high frequency bands are used in 4G (4th generation) and / or subsequent communication systems (e.g., 5G) and the cell coverage of base stations decreases, the number of base stations required to cover a specific area has increased. Consequently, the burden of installation costs for operators to install base stations has also increased. To minimize base station installation costs, a structure has been proposed in which the DU and RU of a base station are separated, with one or more RUs connected to a single DU via a wired network, and one or more geographically distributed RUs deployed to cover a specific area. Below, with reference to FIG. 2, deployment structures and extension examples of base stations according to various embodiments of the present disclosure are described.

[0032] Figure 2 illustrates an example of an interface between an upper network node and a lower network node.

[0033] FIG. 2 illustrates an interface between an upper network node and a lower network node. The interface between the upper network node and the lower network node may include a fronthaul interface. Fronthaul refers to the space between entities between a wireless LAN and a base station, unlike backhaul between a base station and a core network. FIG. 2 illustrates an example of a fronthaul structure between an upper network node (210) and one lower network node (220), but this is merely for convenience of explanation and the present disclosure is not limited thereto. In other words, an embodiment of the present disclosure may also be applied to a fronthaul structure between one upper network node and a plurality of lower network nodes. For example, an embodiment of the present disclosure may be applied to a fronthaul structure between one upper network node and two lower network nodes. Additionally, an embodiment of the present disclosure may also be applied to a fronthaul structure between one upper network node and three lower network nodes.

[0034] For example, an upper network node may include a DU (digital unit / distributed unit). An upper network node may be referred to as a DU. A lower network node may include a RU (radio unit) or an MMU (massive MIMO unit). A lower network node may be referred to as a RU or an MMU.

[0035] Referring to FIG. 2, the base station (110) may include an upper network node (210) and a lower network node (220). The fronthole (215) between the upper network node (210) and the lower network node (220) may be operated via an Fx interface. For the operation of the fronthole (215), an interface such as eCPRI (enhanced common public radio interface) or ROE (radio over ethernet) may be used.

[0036] As communication technology develops, mobile data traffic increases, and consequently, the bandwidth requirements for the fronthaul between the digital unit and the wireless unit have increased significantly. In a deployment such as a C-RAN (centralized / cloud radio access network), the upper network node (210) performs functions for PDCP (packet data convergence protocol), RLC (radio link control), MAC (media access control), and PHY (physical), and the lower network node (220) can be implemented to perform functions for the PHY layer in addition to RF (radio frequency) functions.

[0037] The upper network node (210) may be responsible for upper layer functions of the wireless network. For example, the upper network node (210) may perform functions of the MAC layer and parts of the PHY layer. Here, parts of the PHY layer are functions of the PHY layer that are performed at a higher level, and may include, for example, channel encoding (or channel decoding), scrambling (or descrambling), modulation (or demodulation), and layer mapping (or layer demapping). According to one embodiment, if the upper network node (210) conforms to the O-RAN standard, it may be referred to as an O-DU (O-RAN DU) (or DU). The upper network node (210) may be replaced and represented as a first network entity or DU for a base station (e.g., gNB) in the embodiments of the present disclosure as necessary.

[0038] The lower network node (220) can perform lower layer functions of the wireless network. For example, the lower network node (220) can perform RF functions, which are part of the PHY layer. Here, part of the PHY layer refers to functions of the PHY layer that are performed at a relatively lower level than the upper network node (210), and may include, for example, iFFT transformation (or FFT transformation), CP (cyclic prefix) insertion (CP removal), and digital beamforming. The lower network node (220) may be referred to as an 'access unit (AU)', 'access point (AP)', 'transmission / reception point (TRP)', 'remote radio head (RRH)', 'radio unit (RU)', or other terms having an equivalent technical meaning. According to one embodiment, if the sub-network node (220) conforms to the O-RAN standard, it may be referred to as an O-RU (O-RAN RU) (or RU). The sub-network node (220) may be replaced with a second network entity or RU for a base station (e.g., gNB) in the embodiments of the present disclosure as needed.

[0039] In the above example, it is described that the upper network node (210) includes a DU and the lower network node (220) includes an RU, but the embodiments of the present disclosure are not limited thereto. A base station according to the embodiments may be implemented in a distributed deployment according to a centralized unit (CU) configured to perform the functions of the upper layers of the access network (e.g., packet data convergence protocol (PDCP), radio resource control (RRC)) and a distributed unit (DU) configured to perform the functions of the lower layers. In this case, the distributed unit (DU) may include a digital unit (DU) and a radio unit (RU). Between a core network (e.g., 5G core or next generation core (NGC)) and a radio network (RAN), the base station may be implemented in a structure in which the CU, DU, and RU are arranged in that order. The interface between the CU and the distributed unit (DU) may be referred to as the F1 interface.

[0040] For example, a centralized unit (CU) can be connected to one or more DUs and perform functions at a higher layer than the DUs. For instance, the CU can perform functions at the radio resource control (RRC) and packet data convergence protocol (PDCP) layers, while the DU and RU can perform functions at lower layers. The DU can perform radio link control (RLC), media access control (MAC), and some functions of the physical (PHY) layer (high PHY), while the RU can perform the remaining functions of the PHY layer (low PHY). Additionally, as an example, a digital unit (DU) can be included in a distributed unit (DU) depending on the distributed deployment implementation of the base station. The following description describes the operations of DU and RU unless otherwise defined, but various embodiments of the present disclosure may be applied to both base station deployments including CU and deployments where DU is directly connected to the core network (i.e., implemented by integrating CU and DU into a single entity base station (e.g., NG-RAN node)).

[0041] Figure 3 illustrates an example of the functional configuration of a communication device.

[0042] The configuration of the communication device (301) exemplified in FIG. 3 can be understood as a configuration of a base station (110), a terminal (120), an upper network node (210), a lower network node (220), a server, or a network element performing an equivalent function. However, the present disclosure is not limited thereto. Terms such as '...part', '...unit' used below refer to a unit that processes at least one function or operation, and this may be implemented in hardware or software, or a combination of hardware and software.

[0043] Referring to FIG. 3, the communication device (301) may include a processor (300), a memory (310), a GNSS receiver (320), an antenna (321), and / or a transceiver (330). However, the present disclosure is not limited thereto. For example, the communication device (301) may not include at least some of the components shown in FIG. 3, or may further include components not shown in FIG. 3.

[0044] The processor (300) controls the overall operations of the communication device (301). The processor (300) may be referred to as a control unit. The processor (300) may include control circuits and / or processing circuits. For example, the processor (300) transmits and receives signals through the transceiver (330) (or through the backhaul communication unit). Additionally, the processor (300) writes and reads data to and from memory (310). Furthermore, the processor (300) may perform the functions of a protocol stack required by the communication standard. Although only the processor (300) is shown in FIG. 3, according to other embodiments, the communication device (301) may include two or more processors.

[0045] For example, the processor (300) may include various processing circuits and / or multiple processors. For example, the term “processor” as used herein, including in the claims, may include various processing circuits including at least one processor, and one or more of said at least one processor may be configured to perform the various functions described below in a distributed manner, individually and / or collectively. As used below, where “processor,” “at least one processor,” and “one or more processors” are described as being configured to perform various functions, these terms encompass situations where one processor performs some of the cited functions and another processor(s) perform other parts of the cited functions, and / or situations where one processor can perform all of the cited functions. Additionally, said at least one processor may include a combination of processors that perform the enumerated / disclosed various functions, for example, in a distributed manner. At least one processor may execute program instructions to achieve or perform the various functions.

[0046] Memory (310) can store data such as basic programs, application programs, and configuration information for the operation of the communication device (301). Memory (310) may be referred to as a storage unit. Memory (310) can store instructions for the operations of the communication device (301). Memory (310) may include hardware components for storing data and / or instructions that are input to or / or output from the processor (300). A set of one or more instructions may be referred to as a program, firmware, operating system, process, routine, sub-routine, and / or application. For example, instructions may represent operations and / or actions to be performed on the data by the processor (300) of the communication device (301). And, memory (310) provides the stored data upon the request of the processor (300). Memory (310) may be composed of volatile memory, non-volatile memory, or a combination of volatile memory and non-volatile memory.

[0047] A GNSS receiver (320) may be used for a global navigation satellite system (GNSS). The GNSS receiver (320) may be configured to receive or acquire one or more GNSS signals transmitted from one or more satellites. For example, the GNSS receiver (320) may be used to identify the location (or geographical location) of a communication device (301) using one or more GNSS signals. For example, the communication device (301) may calculate location information of the communication device (301) using one or more GNSS signals. For example, the GNSS receiver (320) may acquire time information using GNSS signals transmitted from a satellite. For example, the GNSS signal may include a signal transmitted from a satellite and / or a signal having a substantially equivalent structure.

[0048] The antenna (321) may be used to transmit a signal or power to an external source (e.g., an external electronic device) or to receive it from an external source. The antenna (321) may include a radiator made of a conductor or a conductive pattern formed on a substrate. For example, the antenna (321) may include a plurality of antennas. As an example, but not limited to, other components (e.g., a radio frequency integrated circuit (RFIC)) may additionally be included in the antenna (321) in addition to the radiator. For example, the antenna (321) may amplify a received signal. For example, the antenna (321) may provide the amplified signal to a GNSS receiver (320).

[0049] According to one embodiment, the antenna (321) may be used to receive GNSS signals. The antenna (321) may receive signals within the satellite communication frequency band. For example, the antenna (321) may be positioned facing the satellite within a communication device.

[0050] The transceiver (330) may be configured to communicate with a terrestrial network element (NE). For example, the terrestrial NE may include a terrestrial-based infrastructure for a terrestrial network.

[0051] The transceiver (330) can perform functions for transmitting and receiving signals in a wired communication environment. The transceiver (330) may include a wired interface for controlling a direct connection between devices through a transmission medium (e.g., copper wire, optical fiber). For example, the transceiver (330) may transmit an electrical signal to another device through a copper wire or perform conversion between an electrical signal and an optical signal. According to one embodiment, a communication device (301) may communicate with a radio unit (RU) through the transceiver (330). In this respect, the transceiver (330) may be referred to as a fronthall transceiver. As an example, but not limited to, the communication device (301) may be connected to a core network or a distributed CU through the transceiver (330).

[0052] The transceiver (330) may perform functions for transmitting and receiving signals in a wireless communication environment. For example, the transceiver (330) may perform a conversion function between a baseband signal and a bit sequence according to the physical layer specifications of the system. For example, when transmitting data, the transceiver (330) generates complex symbols by encoding and modulating the transmitted bit sequence. Also, when receiving data, the transceiver (330) restores the received bit sequence by demodulating and decoding the baseband signal. Additionally, the transceiver (330) may include a plurality of transmission and reception paths. Also, according to one embodiment, the transceiver (330) may be connected to a core network or to other nodes (e.g., an integrated access backhaul).

[0053] The transceiver (330) can transmit and receive signals. The transceiver (330) can function as a fronthall transceiver. For example, the communication device (301) can transmit or receive management plane (M-plane) messages through the transceiver (330). For example, the communication device (301) can transmit or receive synchronization plane (S-plane) messages through the transceiver (330). For example, the communication device (301) can transmit or receive control plane (C-plane) messages through the transceiver (330). For example, the communication device (301) can transmit or receive user plane (U-plane) messages through the transceiver (330). Although only a transceiver (330) is shown in FIG. 3, according to other embodiments, the communication device (301) may include two or more transceivers.

[0054] The transceiver (330) transmits and receives signals as described above. Accordingly, all or part of the transceiver (330) may be referred to as a 'communication unit', 'transmitter unit', 'receiver unit', or 'transmitter / receiver unit'. Furthermore, in the following description, transmission and reception performed via a wireless channel are used to mean that processing as described above is performed by the transceiver (330).

[0055] *52 Although not illustrated in Figure 3, the transceiver (330) may further include a backhaul transceiver for connecting to a core network or another base station. The backhaul transceiver provides an interface for communicating with other nodes within the network. That is, the backhaul transceiver converts a sequence of bits transmitted from a base station to another node, e.g., another connection node, another base station, an upper node, a core network, etc., into a physical signal, and converts a physical signal received from another node into a sequence of bits.

[0056] The configuration of the communication device (301) illustrated in FIG. 3 is merely an example, and the examples of communication devices (301) that perform embodiments of the present disclosure are not limited to the configuration illustrated in FIG. 3. In some embodiments, some configurations may be added, deleted, or changed.

[0057] In the present disclosure, a spoofing signal may be referred to as a forged signal that impersonates a normal GNSS signal. A spoofing signal may cause a communication device receiving the spoofing signal to obtain incorrect location information and / or incorrect time information. A spoofing signal may distort the location information and / or time information of the communication device receiving the spoofing signal. For example, the location information and / or time information of a satellite included in the spoofing signal may be manipulated information. For example, the identification information included in the spoofing signal may be manipulated. For example, the spoofing signal may be transmitted from a satellite and an external communication device, but the identification information included in the spoofing signal may point to said satellite. For example, if a GNSS signal is not transmitted from the satellite indicated by the identification information included in the GNSS signal, the GNSS signal may be determined to be a spoofing signal. For example, if a GNSS signal is transmitted from a satellite represented by identification information included in the GNSS signal, the GNSS signal can be determined to be a normal signal.

[0058] In the present disclosure, a communication device (301) may be described for a technique to determine or identify whether a received GNSS signal is a spoofing signal or a normal signal. The communication device (301) may execute a method of obtaining reference coordinate information of satellites to determine whether a GNSS signal is a spoofing signal or a normal signal. The communication device (301) may execute a method of determining or identifying whether a GNSS signal is a spoofing signal or a normal signal based on the reference coordinate information of satellites and the received GNSS signal. Such a method will be described and illustrated with reference to FIGS. 4 through 7c.

[0059] FIG. 4 illustrates an example of a communication device that receives GNSS signals.

[0060] Referring to FIG. 4, a communication device (301) can receive or acquire GNSS signals (411, 421, 431) through an antenna (321). A communication device (301) can receive or acquire GNSS signals (411, 421, 431) through a GNSS receiver (e.g., a GNSS receiver (320)). A GNSS signal (411) may be transmitted from a satellite (410). A GNSS signal (421) may be transmitted from a network node (420). A GNSS signal (431) may be transmitted from a satellite (430). A communication device (301) can determine or identify whether each of the received GNSS signals (411, 421, 431) is a normal signal or a spoofing signal.

[0061] The communication device (301) can identify location information of the communication device (301), time synchronization information, and / or orbit information of the satellites. For example, the location information of the communication device (301) may have relatively high accuracy. For example, the location information of the communication device (301) may be stored in memory (310). For example, the location information of the communication device (301) may be stored in response to input from the user of the communication device (301). For example, the location information of the communication device (301) may be calculated or obtained based on one or more GNSS signals transmitted from one or more satellites (e.g., satellite (430), satellite (440)). For example, the communication device (301) may calculate or obtain the location information of the communication device (301) using one or more GNSS signals that are determined or identified as normal signals. Time synchronization information can be obtained or received from the first ground NE (401) using a transceiver (e.g., transceiver (330)). Orbit information of the satellites can be obtained or received from the second ground NE (402) using a transceiver (330).

[0062] The communication device (301) can obtain reference coordinate information of the satellites based on the location information of the communication device (301), time synchronization information, and / or orbit information of the satellites. For example, the reference coordinate information of the satellites may indicate the location of the satellites for a GNSS system. For example, the reference coordinate information of the satellites may indicate the location of satellites registered in the GNSS (e.g., satellite (430), satellite (440)). In FIG. 4, satellite (430) and satellite (440) are shown as satellites registered in the GNSS, but the embodiment is not limited thereto. One or more satellites not shown in FIG. 4 may be registered in the GNSS.

[0063] According to one embodiment, the reference coordinate information of the satellites may represent the reference coordinates of the satellites relative to the communication device (301). For example, the reference coordinate information of the satellites may include the reference coordinates of the satellites at the current time and after the current time. For example, the reference coordinates may be referenced to or correspond to the coordinates where the satellites are scheduled to be located at the corresponding time. For example, the communication device (301) may use the reference coordinate information of the satellites to determine or identify whether each of the received GNSS signals is a normal signal or a spoofing signal.

[0064] The communication device (301) can identify identification information contained in each of the received GNSS signals (411, 421, 431). For example, the communication device (301) can obtain first identification information from the GNSS signal (411). For example, the GNSS signal (411) may be a spoofing signal. For example, the first identification information may represent a satellite other than the satellite (410). For example, the first identification information may not represent the satellite (410). For example, the first identification information may represent the satellite (440). The communication device (301) can obtain or calculate a list of satellites located below the horizon according to the location of the communication device (301) by using the reference coordinate information of the satellites. For example, the communication device (301) can identify that the satellite (440) is located below the horizon according to the location of the communication device (301) by using the list. For example, reference coordinate information of the satellites may include the elevation angle of the satellite (440) relative to the communication device (301) which is less than a reference angle (e.g., about 0 degrees) corresponding to the horizon. For example, because the elevation angle of the satellite (440) relative to the communication device (301) is less than about 0 degrees, the satellite (440) may not be visible from the communication device (301). For example, the communication device (301) can use the elevation angle of the satellite (440) to identify that a GNSS signal transmitted from the satellite (440) is not receivable at the current time. For example, the communication device (301) can determine or identify the GNSS signal (411) as a spoofing signal based on the determination that the elevation angle of the satellite (440) is less than about 0 degrees.

[0065] According to one embodiment, the communication device (301) can identify second identification information included in the GNSS signal (421). For example, the GNSS signal (421) may be a spoofing signal. For example, the GNSS signal (421) may be generated at a network node (420) to interfere with the GNSS-related functions of the communication device (301). For example, the communication device (301) may obtain second identification information from the GNSS signal (421). For example, the second identification information may not represent the network node (420). For example, the second identification information may represent a satellite (430). The communication device (301) may obtain or identify the reference coordinates of the satellite (430) relative to the location of the communication device (301) by using the reference coordinate information of the satellites. The communication device (301) may obtain the coordinate information of the satellite (430) by using the GNSS signal (421). For example, the coordinate information of a satellite (430) obtained using a GNSS signal (421) may include the coordinates of the satellite (430) relative to the communication device (301). For example, the communication device (301) may calculate, obtain, or identify the distance between the reference coordinates of the satellite (430) according to the reference coordinate information of the satellites and the coordinates of the satellite (430) according to the GNSS signal (421). For example, the communication device (301) may determine or identify the GNSS signal (421) as a spoofing signal based on the determination that the distance is greater than the reference distance. For example, the communication device (301) may refrain from providing location services using the GNSS signal (421) based on the determination that the GNSS signal (421) is a spoofing signal. For example, the communication device (301) may refrain from using the GNSS signal (421) to calculate the location information of the communication device (301) based on the determination that the GNSS signal (421) is a spoofing signal.For example, the communication device (301) may refrain from obtaining time information using the GNSS signal (421) based on the determination that the GNSS signal (421) is a spoofing signal. For example, the communication device (301) may ignore or block the GNSS signal (421) based on the determination that the GNSS signal (421) is a spoofing signal. For example, the communication device (301) may perform masking on the GNSS signal (421). For example, the communication device (301) may not receive or block GNSS signals corresponding to the second identification information included in the GNSS signal (421). For example, the communication device (301) may report a notification indicating the detection of a spoofing signal to the network administrator based on the determination that the GNSS signal (421) is a spoofing signal. For example, the communication device (301) can obtain location information of the communication device (301) by using a location tracking method different from GNSS, depending on the determination that the GNSS signal (421) is a spoofing signal.

[0066] According to one embodiment, the communication device (301) can identify third identification information included in the GNSS signal (431). For example, the GNSS signal (431) may be a normal signal. For example, the communication device (301) may obtain third identification information from the GNSS signal (431). For example, the third identification information may represent a satellite (430). The communication device (301) may obtain or identify the reference coordinates of the satellite (430) relative to the location of the communication device (301) by using the reference coordinate information of the satellites. The communication device (301) may obtain coordinate information of the satellite (430) by using the GNSS signal (431). For example, the coordinate information of the satellite (430) obtained by using the GNSS signal (431) may include the coordinates of the satellite (430) relative to the communication device (301). For example, the communication device (301) can calculate, obtain, or identify the distance between the reference coordinates of the satellite (430) according to the reference coordinate information of the satellites and the coordinates of the satellite (430) according to the GNSS signal (431). For example, the communication device (301) can determine or identify the GNSS signal (431) as a normal signal based on the determination that the distance is smaller than the reference distance. For example, the communication device (301) can provide location services using the GNSS signal (431) based on the determination that the GNSS signal (431) is a normal signal. For example, the communication device (301) can calculate location information of the communication device (301) using the GNSS signal (431) based on the determination that the GNSS signal (431) is a normal signal. For example, the communication device (301) can obtain time information using the GNSS signal (431) based on the determination that the GNSS signal (431) is a normal signal. For example, the communication device (301) can release the blocking of the GNSS signal containing identification information representing the satellite (430) based on the determination that the GNSS signal (431) is a normal signal.

[0067] A communication device (301) can communicate with a first terrestrial network element (401) using a transceiver (e.g., transceiver (330)). For example, the communication device (301) can connect to the first terrestrial network element (401) using a transceiver (330). The first terrestrial network element (401) can be configured to provide a time synchronization function to the terrestrial network. The first terrestrial network element (401) can provide time synchronization information so that devices within the terrestrial network (e.g., terrestrial network element, communication device (301)) maintain the same reference time. For example, the first terrestrial network element (401) can provide time synchronization information to the communication device (301) upon a request from the communication device (301) connected to the first terrestrial network element (401). The communication device (301) can set the system time within the communication device (301) using the time synchronization information. For example, the first ground NE (401) may cause the system time of the communication device (301) to be synchronized to a standard time using a time synchronization protocol (e.g., NTP (network time protocol), PTP (precision time protocol)). For example, the first ground NE may include a PTP (precision time protocol) server (or PTP grandmaster) and / or an NTP (network time protocol) server.

[0068] A communication device (301) can communicate with a second ground NE (402) using a transceiver (330). For example, the second ground NE (402) may include an A-GNSS (assisted-GNSS) server. For example, the A-GNSS server may include an A-GPS (assisted-global positioning system) server. For example, the communication device (301) can connect to the second ground NE (402) using a transceiver (330). The second ground NE (402) may be configured to assist GNSS. For example, the second ground NE (402) may provide satellite orbit information to the communication device (301) upon a request from the communication device (301) connected to the second ground NE (402). For example, the satellites may be registered in a GNSS system. For example, the satellites may be registered in the second ground NE (402). For example, the communication device (301) can reduce the time required to acquire GNSS signals from satellites by using orbital information of satellites. For example, the communication device (301) can reduce the time required to acquire or calculate position information of the communication device (301) by using orbital information of satellites.

[0069] According to one embodiment, the second ground NE (402) may include or store orbit information of satellites. The second ground NE (402) may acquire or receive orbit information of satellites from one or more reference GNSS receivers. For example, one or more reference GNSS receivers may be deployed globally. For example, the second ground NE (402) may receive or acquire GNSS signals from one or more reference GNSS receivers. For example, the GNSS signals may include satellite data (e.g., navigation data). The second ground NE (402) may acquire orbit information of satellites by decoding the satellite data. The second ground NE (402) may provide orbit information of satellites to the communication device (301) upon a request from the communication device (301) connected to the second ground NE (402).

[0070] According to one embodiment, the orbit information of the satellites may represent the orbits of each satellite over time. For example, the orbit information of the satellites may represent the orbits of each satellite over a certain period. For example, the orbit information of the satellites may represent the current orbit of each satellite, the past orbit of each satellite, and / or the projected orbit of each satellite. For example, the projected orbit of each satellite may be referenced as the orbit where each satellite will be located in the future.

[0071] According to one embodiment, the orbital information of the satellites may include ephemeris and / or almanac. For example, ephemeris may represent the orbits of the satellites with relative precision. For example, the precision of the almanac may be lower than that of the ephemeris. For example, ephemeris may include at least a portion of the almanac. For example, the types of data included in the ephemeris may be described with reference to [Table 1].

[0072]

[0073] [Table 1] is only a part of the data included in Ephemeris. The communication device (301) can calculate reference coordinate information of the satellites based on the orbital information of the satellites including the data exemplified in [Table 1]. For example, the method by which the communication device (301) calculates reference coordinate information of the satellites will be exemplified and explained in FIG. 6.

[0074] According to one embodiment, the communication device (301) may include an error based on a previously received spoofing signal. For example, the spoofing signal may cause an error in location information stored in the communication device (301) and / or an error in time information applied to the communication device (301).

[0075] The communication device (301) can acquire or calculate location information based on a normal signal (e.g., GNSS signal (431)). The communication device (301) can compare the acquired first location information with the second location information stored in the communication device (301). For example, the communication device (301) can identify the distance between the first coordinates represented by the acquired first location information and the second coordinates represented by the stored second location information. For example, the communication device (301) can maintain the stored second location information based on the determination that the distance is smaller than a reference distance. For example, the communication device (301) can identify or detect that the communication device (301) is distorted by a spoofing signal based on the determination that the distance is larger than a reference distance. For example, the communication device (301) can perform recovery of the system of the communication device (301) based on identifying that the communication device (301) is distorted by a spoofing signal. For example, the communication device (301) can identify or detect the occurrence of an error in the stored second location information based on the determination that the distance is greater than the reference distance. For example, the communication device (301) can remove the second location information based on identifying the occurrence of an error in the second location information. For example, the communication device (301) can calculate or obtain the location information of the communication device (301) using normal GNSS signals based on identifying the occurrence of an error in the second location information.

[0076] According to one embodiment, a communication device (301) can obtain first time information using a normal signal (e.g., a GNSS signal (431)). The communication device (301) can identify second time information applied to the communication device (301). For example, the communication device (301) can set the system time according to the second time information. For example, the communication device (301) can calculate, identify, or obtain a time offset between the first time information and the second time information. For example, the communication device (301) can retain the second time information based on a determination that the time offset is smaller than a reference offset. For example, the communication device (301) can identify or detect that the communication device (301) has been distorted by a spoofing signal based on a determination that the time offset is larger than a reference offset. For example, the communication device (301) can perform system recovery of the communication device (301) based on identifying that the communication device (301) is distorted by a spoofing signal. For example, the communication device (301) can identify or detect the occurrence of an error in the second time information applied to the communication device (301) based on the determination that the time offset is greater than the reference offset. For example, the communication device (301) can remove the second time information based on identifying the occurrence of an error in the second time information. For example, the communication device (301) can perform time synchronization based on identifying the occurrence of an error in the second time information. For example, the communication device (301) can request time synchronization information from the first ground NE (401) to perform time synchronization. For example, the communication device (301) can set the system time of the communication device (301) using the time synchronization information obtained from the first ground NE (401). As a non-limiting example, the communication device (301) may set the system time by applying the first time information as it identifies the occurrence of an error in the second time information.

[0077] FIG. 5 illustrates examples of operations of a communication device for determining whether a GNSS signal is a spoofing signal or a normal signal. The operations of FIG. 5 can be performed in the communication device (301) of FIG. 3 and FIG. 4.

[0078] Referring to FIG. 5, in operation 501, a communication device (301) (e.g., processor (300)) can obtain reference coordinate information of satellites based on first location information of the communication device (301), time synchronization information obtained using a transceiver (e.g., transceiver (330)), and orbit information of satellites obtained using a transceiver (330). For example, the first location information of the communication device (301) can be stored in the memory (e.g., memory (310)) of the communication device (301). For example, the first location information of the communication device (301) can be stored in response to input from a user of the communication device (301). For example, the first location information of the communication device (301) can be calculated or obtained based on one or more GNSS signals transmitted from one or more satellites (e.g., satellite (430), satellite (440)). Time synchronization information can be obtained from the first ground NE (401) of FIG. 4. Orbit information of the satellites can be obtained from the second ground NE (402) of FIG. 4. The satellites may be referenced or correspond to satellites for providing GNSS.

[0079] According to one embodiment, the reference coordinate information of the satellites may include the coordinates of each satellite relative to the location of the communication device (301). The reference coordinate information of the satellites may represent the predicted coordinates of each satellite over time. For example, the descriptions of the reference coordinate information of the satellites in FIG. 4 may be referenced for the reference coordinate information of the satellites. For example, a method for obtaining the reference coordinate information of the satellites will be described and illustrated in FIG. 6.

[0080] In operation 503, a communication device (301) (e.g., processor (300)) can obtain coordinate information of a target satellite (e.g., satellite (430), satellite (440)) among the satellites that is indicated by the target GNSS signal, based on the target GNSS signal (e.g., GNSS signal (411), GNSS signal (421), target GNSS signal (431)) received using a GNSS receiver. For example, the communication device (301) can identify identification information included in the target GNSS signal. For example, the communication device (301) can identify a target satellite among the satellites that is indicated by the identification information. For example, the communication device (301) can obtain coordinate information of a target satellite indicated by the target GNSS signal using the target GNSS signal.

[0081] In operation 505, the communication device (301) (e.g., processor (300)) can determine or identify whether the target GNSS signal is a normal signal or a spoofing signal based on the reference coordinate information of the satellites and the coordinate information of the target satellite.

[0082] According to one embodiment, the reference coordinate information of the satellites may include the reference coordinates of the target satellite relative to the communication device (301). For example, the coordinate information of the target satellite indicated by the target GNSS signal may include the coordinates of the target satellite. The communication device (301) may calculate or identify the distance between the reference coordinates of the target satellite and the coordinates of the target satellite. For example, the communication device (301) may determine the target GNSS signal as a normal signal based on the determination that the distance is smaller than the reference distance. For example, the communication device (301) may determine the target GNSS signal as a spoofing signal based on the determination that the distance is not smaller than the reference distance. For example, the reference distance may be set by the user of the communication device (301).

[0083] According to one embodiment, reference coordinate information of the satellites may include elevation angles of the satellites relative to the position of the communication device (301). For example, the reference coordinate information of the satellites may represent a first portion of satellites having an elevation angle greater than a reference angle (e.g., about 0 degrees) corresponding to the horizon relative to the position of the communication device (301), and a second portion of satellites having an elevation angle smaller than the reference angle. For example, the communication device (301) may determine a target GNSS signal as a spoofing signal based on the determination that a target satellite is included in the second portion of the satellites.

[0084] According to one embodiment, the communication device (301) can use reference coordinate information of the satellites to enhance the reliability of determining that a GNSS signal received using a GNSS receiver is a spoofing signal. For example, the communication device (301) can execute the operations of FIG. 5 through a software update without changing the hardware (e.g., an existing GNSS receiver). The communication device (301) can avoid increased costs due to hardware changes.

[0085] In operation 507, the communication device (301) (e.g., processor (300)) can calculate second position information of the communication device (301) using the target GNSS signal based on the determination that the target GNSS signal is a normal signal. As an example, not limited to, the communication device (301) can obtain time information using the target GNSS signal based on the determination that the target GNSS signal is a normal signal.

[0086] In operation 509, the communication device (301) (e.g., processor (300)) may refrain from calculating second location information of the communication device (301) using the target GNSS signal based on the determination that the target GNSS signal is a spoofing signal. As an example, but not limited to, the communication device (301) may refrain from obtaining time information using the target GNSS signal based on the determination that the target GNSS signal is a spoofing signal. For example, the communication device (301) may block or ignore the target GNSS signal based on the determination that the target GNSS signal is a spoofing signal. For example, the communication device (301) may perform masking on identification information within the target GNSS signal. For example, the communication device (301) may refuse or block reception of the GNSS signal having masked identification information.

[0087] FIG. 6 illustrates examples of operations of a communication device for obtaining reference position coordinates of satellites. The operations of FIG. 6 can be performed in the communication device (301) of FIG. 3 and FIG. 4.

[0088] Referring to FIG. 6, in operation 601, a communication device (301) (e.g., processor (300)) can obtain reference ECEF (earth-centered, earth-fixed) coordinates of the satellites based on the first position information of the communication device (301), time synchronization information, and orbit information of the satellites. The ECEF coordinate system can be referenced as a three-dimensional orthogonal coordinate system with the center of the Earth as the origin. For example, the direction of the x-axis of the ECEF coordinate system can be directed toward the point where the prime meridian (e.g., 0 degrees longitude) and the equator (e.g., 0 degrees latitude) meet at the center of the Earth. For example, the direction of the y-axis of the ECEF coordinate system can be directed toward the point where the equator meets 90 degrees east longitude at the center of the Earth. For example, the direction of the z-axis of the ECEF coordinate system can be directed toward the point where the Earth's axis of rotation meets the North Pole at the center of the Earth. Table 1 of FIG. 4 can be referenced for the orbit information of the satellites. For example, the method by which the communication device (301) obtains the reference ECEF coordinates of each of the satellites may refer to the following mathematical formulas. In the following mathematical formulas, μ represents the value of the Earth's gravitational constant. μ may be defined in WGS 84 (World Geodetic System 1984). For example, WGS 84 may be a standard used for satellite navigation. μ is 3.986005 × 10⁻⁶ 14 meter 3 / sec 3 It can be. In the following mathematical formulas represents the value of the Earth's rotation speed. can be defined in WGS 84. is 7.2921151467×10 -5 It can be rad / sec.

[0089]

[0090]

[0091]

[0092]

[0093]

[0094]

[0095]

[0096]

[0097]

[0098]

[0099]

[0100]

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107]

[0108]

[0109]

[0110]

[0111]

[0112]

[0113]

[0114]

[0115]

[0116]

[0117]

[0118]

[0119]

[0120]

[0121]

[0122]

[0123]

[0124]

[0125]

[0126]

[0127]

[0128]

[0129]

[0130]

[0131] The communication device (301) can obtain the reference ECEF coordinates of each of the satellites using the mathematical formulas described above.

[0132] In operation 603, the communication device (301) (e.g., processor (300)) can obtain the satellite's reference ENU (east-north-up) coordinates for the location of the communication device (301) by using the satellite's reference ECEF coordinates. The ENU coordinate system can be referenced as a coordinate system based on a specific point on the surface of the earth. For example, the ENU coordinate system may be a coordinate system in which the location of the communication device (301) is set as the origin. For example, in the ENU coordinate system, the direction of the E-axis may be east from the origin. For example, in the ENU coordinate system, the direction of the N-axis may be north from the origin. For example, in the ENU coordinate system, the direction of the U-axis may be perpendicular from the origin (e.g., a direction opposite to the direction of gravity).

[0133] According to one embodiment, the communication device (301) may calculate or obtain the ECEF coordinates of the communication device (301) in order to obtain reference ENU coordinates of satellites for the location of the communication device (301). For example, the ECEF coordinates of the communication device (301) may be calculated from the LLH (latitude longitude height) coordinates of the communication device (301). Changing the LLH coordinates of the communication device (301) to the ECEF coordinates of the communication device (301) is described and illustrated with reference to FIG. 7a.

[0134]

[0135]

[0136]

[0137]

[0138]

[0139]

[0140]

[0141]

[0142]

[0143]

[0144]

[0145] According to one embodiment, the communication device (301) can obtain the ECEF coordinates (P(x, y, z)) of a point (700) using the mathematical formulas described above. For example, the ECEF coordinates (P(x, y, z)) of the point (700) may be the ECEF coordinates of the communication device (301). The ECEF coordinate system may be referenced as a three-dimensional orthogonal coordinate system with the center of the Earth as the origin (e.g., point (711)). For example, point (711) may correspond to the center of the Earth. For example, the direction of the x-axis (701) of the ECEF coordinate system may be directed toward the point where the prime meridian (e.g., 0 degrees longitude) and the equator (e.g., 0 degrees latitude) meet at the center of the Earth. For example, the direction of the y-axis (702) of the ECEF coordinate system may be directed toward the point where the equator meets 90 degrees east longitude from the center of the Earth. For example, the direction of the z-axis (703) of the ECEF coordinate system can be directed from the center of the Earth toward the point where the Earth's axis of rotation and the North Pole meet.

[0146] Referring again to FIG. 6, in operation 603, the communication device (301) can obtain reference ENU coordinates of the satellites using the reference ECEF coordinates of the satellites and the ECEF coordinates of the communication device (301). Obtaining reference ENU coordinates of the satellites using the reference ECEF coordinates of the satellites and the ECEF coordinates of the communication device (301) is explained and exemplified with reference to FIG. 7b.

[0147] FIG. 7b illustrates an example of obtaining the reference ENU coordinates of a satellite.

[0148] Referring to FIG. 7b, the ECEF coordinates (Gx, Gy, Gz) of the satellite (730) may be included in the reference ECEF coordinates of the satellites calculated in operation 601 of FIG. 6. The ECEF coordinates (Bx, By, Bz) of the communication device (740) may be an example of the ECEF coordinates (P(x, y, z)) of the point (700) exemplified in FIG. 7a. The communication device (740) may be an example of the communication device (301).

[0149] The following mathematical formula may be referenced to replace the ECEF coordinates (Gx, Gy, Gz) of the satellite (730) with the reference ENU coordinates of the satellite (730). For example, the ENU coordinate system may be a coordinate system based on the location of the communication device (740). For example, the ENU coordinate system may be a coordinate system where the location of the communication device (740) is set as the origin. For example, in the ENU coordinate system, the direction of the E-axis (741) may be towards the east from the origin. For example, in the ENU coordinate system, the direction of the N-axis (742) may be towards the north from the origin. For example, in the ENU coordinate system, the direction of the U-axis (743) may be towards the vertical direction from the origin (e.g., a direction opposite to the direction of gravity).

[0150]

[0151]

[0152] According to one embodiment, the communication device (740) can obtain the reference ENU coordinates of the satellite (730).

[0153] Referring again to FIG. 6, in operation 605, the communication device (301) (e.g., processor (300)) can obtain reference azimuths and reference elevations of the satellites based on the reference ENU coordinates of the satellites. For example, to obtain the reference ENU coordinates of the satellites, the descriptions of FIG. 7b may be referenced. Obtaining the reference azimuths and reference elevations of the satellites based on the reference ENU coordinates of the satellites is described and illustrated with reference to FIG. 7c.

[0154]

[0155]

[0156]

[0157]

[0158]

[0159] Referring again to FIG. 6, in operation 605, the communication device (301) can obtain reference azimuths of satellites and reference elevation angles of satellites. The communication device (301) can store a list representing the reference azimuths of satellites and reference elevation angles of satellites. The communication device (301) can obtain or generate reference coordinate information of satellites including the list.

[0160] In operation 607, the communication device (301) (e.g., processor (300)) can identify a first portion of satellites having an elevation angle greater than a reference angle and a second portion of satellites having an elevation angle smaller than a reference angle. For example, the reference angle may correspond to the horizon according to the position of the communication device (301). For example, the reference angle may be approximately 0 degrees. For example, the communication device (301) can identify the first portion of satellites and the second portion of satellites using reference coordinate information of the satellites.

[0161] According to one embodiment, a communication device (301) can identify identification information included in a received GNSS signal using a GNSS receiver (e.g., a GNSS receiver (320)). For example, the communication device (301) can determine or identify the GNSS signal as a spoofing signal based on a determination that the target satellite indicated by the identification information is included in a second part of the satellites.

[0162] In an embodiment according to the present disclosure, a communication device (e.g., communication device (301)) can determine or identify whether a received GNSS signal is a normal signal or a spoofing signal using an existing GNSS receiver. The communication device (301) can obtain time synchronization information and satellite orbit information by connecting to a ground network. The communication device (301) can obtain reference coordinate information of the satellites based on the location information of the communication device (301), time synchronization information, and satellite orbit information. Since the time synchronization information is obtained from a first ground NE configured to provide a time synchronization function to the ground network, the accuracy of the time information represented by the time synchronization information may be relatively high. Since the satellite orbit information is obtained from a second ground NE configured to assist GNSS, the accuracy of the scheduled coordinates of the satellites represented by the satellite orbit information may be relatively high. Therefore, the accuracy of the satellite reference coordinate information may be relatively high. The communication device (301) can use reference coordinate information of the satellites to enhance the reliability of determining that a GNSS signal received using a GNSS receiver is a spoofing signal. For example, the communication device (301) can implement embodiments according to the present disclosure through software updates without changing hardware (e.g., existing GNSS receiver). Through embodiments according to the present disclosure, the communication device (301) can avoid increased costs due to hardware changes.

[0163] The effects obtainable from the present disclosure are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art to which the present disclosure belongs from the description below.

[0164] The technical problems to be solved in this disclosure are not limited to those mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which this disclosure pertains.

[0165] As described above, the communication device may include a transceiver for communicating with a terrestrial network element (NE). The communication device may include a receiver configured to receive a global navigation satellite system (GNSS) signal. The communication device may include a memory comprising one or more storage media for storing instructions. The communication device may include at least one processor comprising processing circuitry. When the instructions are executed individually or collectively by the at least one processor, the communication device may cause the communication device to obtain reference coordinate information of the satellites based on first location information of the communication device, time synchronization information obtained using the transceiver, and orbit information of the satellites obtained using the transceiver. When the above instructions are executed individually or collectively by the at least one processor, they may cause the communication device to obtain coordinate information of a target satellite represented by the target GNSS signal among the satellites based on the target GNSS signal received using the receiver. When the above instructions are executed individually or collectively by the at least one processor, they may cause the communication device to determine whether the target GNSS signal is a normal signal transmitted from the target satellite or a spoofing signal not transmitted from the target satellite based on the reference coordinate information and the coordinate information.When the above instructions are executed individually or collectively by the at least one processor, they may cause the communication device to calculate a second position information of the communication device using the target GNSS signal based on the determination that the target GNSS signal is the normal signal. When the above instructions are executed individually or collectively by the at least one processor, they may cause the communication device to refrain from calculating the second position information of the communication device using the target GNSS signal based on the determination that the target GNSS signal is the spoofing signal.

[0166] According to one embodiment, the reference coordinate information may include the reference coordinates of the target satellite relative to the communication device. The coordinate information may include the coordinates of the target satellite relative to the communication device. When the instructions are executed individually or collectively by the at least one processor, the communication device may be caused to determine the target GNSS signal as the normal signal based on a determination that the distance between the reference coordinates and the coordinates is less than the reference distance. When the instructions are executed individually or collectively by the at least one processor, the communication device may be caused to determine the target GNSS signal as the spoofing signal based on a determination that the distance between the reference coordinates and the coordinates is not less than the reference distance.

[0167] According to one embodiment, the reference coordinate information may include a reference elevation angle of the target satellite relative to the communication device. When the instructions are executed individually or collectively by the at least one processor, the communication device may be caused to determine the target GNSS signal as the spoofing signal based on the determination that the reference elevation angle is smaller than the reference angle corresponding to the horizon relative to the position of the communication device.

[0168] According to one embodiment, when the instructions are executed individually or collectively by the at least one processor, the communication device may be caused to acquire time information using the target GNSS signal based on the determination that the target GNSS signal is the normal signal. When the instructions are executed individually or collectively by the at least one processor, the communication device may be caused to refrain from acquiring time information using the target GNSS signal based on the determination that the target GNSS signal is the spoofing signal.

[0169] According to one embodiment, when the instructions are executed individually or collectively by the at least one processor, the communication device may be caused to identify a time offset between the acquired time information and other time information applied to the communication device, based on a determination that the target GNSS signal is the normal signal. When the instructions are executed individually or collectively by the at least one processor, the communication device may be caused to perform time synchronization using the time synchronization information based on identifying the time offset greater than the reference offset, based on a determination that the target GNSS signal is the normal signal. When the instructions are executed individually or collectively by the at least one processor, the communication device may be caused to maintain the other time information applied to the communication device based on identifying the time offset smaller than the reference offset, based on a determination that the target GNSS signal is the normal signal.

[0170] According to one embodiment, when the instructions are executed individually or collectively by the at least one processor, the communication device may be caused to identify the distance between the first coordinates represented by the first position information and the second coordinates represented by the second position information, based on the determination that the target GNSS signal is the normal signal. When the instructions are executed individually or collectively by the at least one processor, the communication device may be caused to identify the occurrence of an error in the first position information of the communication device based on identifying the distance greater than the reference distance, based on the determination that the target GNSS signal is the normal signal. When the instructions are executed individually or collectively by the at least one processor, the communication device may be caused to maintain the first position information of the communication device based on identifying the distance smaller than the reference distance, based on the determination that the target GNSS signal is the normal signal.

[0171] According to one embodiment, the time synchronization information may be received through the transceiver from at least one of a PTP (precision time protocol) server or an NTP (network time protocol) server.

[0172] According to one embodiment, the orbit information of the satellites can be received through the transceiver from an A-GNSS (assisted-GNSS) server configured to assist GNSS.

[0173] A method performed in a communication device having a transceiver for communicating with a terrestrial network element (NE) as described above and a receiver configured to receive a global navigation satellite system (GNSS) signal may include an operation of obtaining reference coordinate information of said satellites based on a first location information of said communication device, time synchronization information obtained using said transceiver, and orbit information of said satellites obtained using said transceiver. The method may include an operation of obtaining coordinate information of a target satellite among said satellites that is indicated by said target GNSS signal based on a target GNSS signal received using said receiver. The method may include an operation of determining whether said target GNSS signal is a normal signal transmitted from said target satellite or a spoofing signal not transmitted from said target satellite based on said reference coordinate information and said coordinate information. The method may include an operation of calculating a second location information of said communication device using said target GNSS signal according to the determination that said target GNSS signal is a normal signal. The above method may include an operation of refraining from calculating the second position information of the communication device using the target GNSS signal based on the determination that the target GNSS signal is the spoofing signal.

[0174] According to one embodiment, the reference coordinate information may include the reference coordinates of the target satellite relative to the communication device. The coordinate information may include the coordinates of the target satellite relative to the communication device. The method may include an operation of determining the target GNSS signal as the normal signal based on a determination that the distance between the reference coordinates and the coordinates is smaller than the reference distance. The method may include an operation of determining the target GNSS signal as the spoofing signal based on a determination that the distance between the reference coordinates and the coordinates is not smaller than the reference distance.

[0175] According to one embodiment, the reference coordinate information may include a reference elevation angle of the target satellite relative to the communication device. The method may include an operation of determining the target GNSS signal as the spoofing signal based on a determination that the reference elevation angle is smaller than a reference angle corresponding to the horizon relative to the position of the communication device.

[0176] According to one embodiment, the method may include an operation of acquiring time information using the target GNSS signal based on a determination that the target GNSS signal is the normal signal. The method may include an operation of refraining from acquiring time information using the target GNSS signal based on a determination that the target GNSS signal is the spoofing signal.

[0177] According to one embodiment, the method may include an operation of identifying a time offset between the acquired time information and other time information applied to the communication device based on a determination that the target GNSS signal is the normal signal. The method may include an operation of performing time synchronization using the time synchronization information based on identifying the time offset greater than the reference offset based on a determination that the target GNSS signal is the normal signal. The method may include an operation of maintaining the other time information applied to the communication device based on identifying the time offset smaller than the reference offset based on a determination that the target GNSS signal is the normal signal.

[0178] According to one embodiment, the method may include an operation of identifying the distance between a first coordinate represented by the first position information and a second coordinate represented by the second position information, based on a determination that the target GNSS signal is the normal signal. The method may include an operation of identifying the occurrence of an error in the first position information of the communication device based on identifying the distance greater than the reference distance based on a determination that the target GNSS signal is the normal signal. The method may include an operation of maintaining the first position information of the communication device based on identifying the distance smaller than the reference distance based on a determination that the target GNSS signal is the normal signal.

[0179] According to one embodiment, the time synchronization information may be received through the transceiver from at least one of a PTP (precision time protocol) server or an NTP (network time protocol) server.

[0180] According to one embodiment, the orbit information of the satellites can be received through the transceiver from an A-GNSS (assisted-GNSS) server configured to assist GNSS.

[0181] In a computer-readable storage medium in which one or more programs as described above are stored, the one or more programs may include instructions that cause the communication device to obtain reference coordinate information of said satellites based on a first position information of said communication device, time synchronization information obtained using said transceiver, and orbit information of said satellites obtained using said transceiver, when the communication device is executed by the communication device having a transceiver for communicating with a terrestrial network element (NE) and a receiver configured to receive a global navigation satellite system (GNSS) signal. The one or more programs may include instructions that cause the communication device to obtain coordinate information of a target satellite indicated by said target GNSS signal among said satellites based on a target GNSS signal received using said receiver when the communication device is executed. The above one or more programs may include instructions that cause the communication device to determine, based on the reference coordinate information and the coordinate information, whether the target GNSS signal is a normal signal transmitted from the target satellite or a spoofing signal not transmitted from the target satellite, when executed by the communication device. The above one or more programs may include instructions that cause the communication device to calculate second position information of the communication device using the target GNSS signal, based on the determination that the target GNSS signal is the normal signal, when executed by the communication device.The above one or more programs may include instructions that cause the communication device to refrain from calculating the second position information of the communication device using the target GNSS signal when executed by the communication device, upon determination that the target GNSS signal is the spoofing signal.

[0182] According to one embodiment, the reference coordinate information may include the reference coordinates of the target satellite relative to the communication device. The coordinate information may include the coordinates of the target satellite relative to the communication device. The one or more programs may include instructions that cause the communication device to determine the target GNSS signal as the normal signal based on a determination that the distance between the reference coordinates and the coordinates is less than the reference distance when executed by the communication device. The one or more programs may include instructions that cause the communication device to determine the target GNSS signal as the spoofing signal based on a determination that the distance between the reference coordinates and the coordinates is not less than the reference distance when executed by the communication device.

[0183] According to one embodiment, the reference coordinate information may include a reference elevation angle of the target satellite relative to the communication device. The one or more programs may include instructions that cause the communication device to determine the target GNSS signal as the spoofing signal based on the determination that the reference elevation angle is smaller than the reference angle corresponding to the horizon relative to the position of the communication device when executed by the communication device.

[0184] According to one embodiment, the one or more programs may include instructions that cause the communication device to acquire time information using the target GNSS signal when executed by the communication device, upon a determination that the target GNSS signal is the normal signal. The one or more programs may include instructions that cause the communication device to refrain from acquiring time information using the target GNSS signal when executed by the communication device, upon a determination that the target GNSS signal is the spoofing signal.

[0185] According to one embodiment, the one or more programs may include instructions that cause the communication device to identify a time offset between the acquired time information and other time information applied to the communication device, based on a determination that the target GNSS signal is the normal signal when executed by the communication device. The one or more programs may include instructions that cause the communication device to perform time synchronization using the time synchronization information, based on identifying the time offset greater than the reference offset, based on a determination that the target GNSS signal is the normal signal when executed by the communication device. The one or more programs may include instructions that cause the communication device to maintain the other time information applied to the communication device, based on identifying the time offset smaller than the reference offset, based on a determination that the target GNSS signal is the normal signal when executed by the communication device.

[0186] According to one embodiment, the one or more programs may include instructions that cause the communication device to identify the distance between the first coordinates represented by the first position information and the second coordinates represented by the second position information, based on the determination that the target GNSS signal is the normal signal when executed by the communication device. The one or more programs may include instructions that cause the communication device to identify the occurrence of an error in the first position information of the communication device based on identifying the distance greater than the reference distance, based on the determination that the target GNSS signal is the normal signal when executed by the communication device. The one or more programs may include instructions that cause the communication device to maintain the first position information of the communication device based on identifying the distance smaller than the reference distance, based on the determination that the target GNSS signal is the normal signal when executed by the communication device.

[0187] According to one embodiment, the time synchronization information may be received through the transceiver from at least one of a PTP (precision time protocol) server or an NTP (network time protocol) server.

[0188] According to one embodiment, the orbit information of the satellites can be received through the transceiver from an A-GNSS (assisted-GNSS) server configured to assist GNSS.

[0189] The various embodiments of this document and the terms used therein are not intended to limit the technical features described in this document to specific embodiments, and should be understood to include various modifications, equivalents, or substitutions of said embodiments. In connection with the description of the drawings, similar reference numerals may be used for similar or related components. The singular form of a noun corresponding to an item may include one or more of said items unless the relevant context clearly indicates otherwise. In this document, phrases such as "A or B," "at least one of A and B," "at least one of A or B," "A, B or C," "at least one of A, B and C," and "at least one of A, B, or C" may each include any one of the items listed together in the corresponding phrase, or all possible combinations thereof. Terms such as "first," "second," or "first" or "second" may be used simply to distinguish said components from other said components and do not limit said components in any other aspect (e.g., importance or order). Where any (e.g., 1st) component is referred to as “coupled” or “connected” to another (e.g., 2nd) component, with or without the terms “functionally” or “communicationly,” it means that said any component may be connected to said other component directly (e.g., via a wire), wirelessly, or through a third component.

[0190] The term “module” as used in the various embodiments of this document may include a unit implemented in hardware, software, or firmware, and may be used interchangeably with terms such as logic, logic block, component, or circuit, for example. A module may be a component formed integrally, or a minimum unit of said component or a part thereof that performs one or more functions. For example, according to one embodiment, a module may be implemented in the form of an application-specific integrated circuit (ASIC).

[0191] Various embodiments of this document may be implemented as software comprising one or more instructions stored in a storage medium (e.g., memory (310)) readable by a machine (e.g., communication device (301) of FIG. 3). For example, a processor (e.g., processor (300)) of the machine (e.g., communication device (301)) may call at least one of the one or more instructions stored from the storage medium and execute it. This enables the machine to be operated to perform at least one function according to the at least one called instruction. The one or more instructions may include code generated by a compiler or code that can be executed by an interpreter. The storage medium readable by the machine may be provided in the form of a non-transitory storage medium. Here, 'non-temporary' simply means that the storage medium is a tangible device and does not contain a signal (e.g., electromagnetic waves), and the term does not distinguish between cases where data is stored semi-permanently and cases where it is stored temporarily.

[0192] According to one embodiment, the method according to the various embodiments disclosed herein may be provided by being included in a computer program product. The computer program product may be traded between a seller and a buyer as a product. The computer program product may be distributed in the form of a device-readable storage medium (e.g., compact disc read-only memory (CD-ROM)), or distributed online (e.g., download or upload) through an application store (e.g., Play Store™) or directly between two user devices (e.g., smartphones). In the case of online distribution, at least a portion of the computer program product may be temporarily stored or temporarily created on a device-readable storage medium, such as the memory of a manufacturer's server, an application store's server, or a relay server.

[0193] According to various embodiments, each component (e.g., module or program) of the components described above may include a singular or multiple entities, and some of the multiple entities may be separated and placed in other components. According to various embodiments, one or more of the components or operations of the aforementioned components may be omitted, or one or more other components or operations may be added. Generally or additionally, multiple components (e.g., module or program) may be integrated into a single component. In this case, the integrated component may perform one or more functions of each of the multiple components in the same or similar manner as those performed by the corresponding component among the multiple components prior to integration. According to various embodiments, operations performed by the module, program, or other components may be executed sequentially, in parallel, iteratively, or heuristically, or one or more of the operations may be executed in a different order, omitted, or one or more other operations may be added.

Claims

1. In a communication device, Transmitter / receiver for communicating with a terrestrial network element (NE); A receiver configured to receive GNSS (global navigation satellite system) signals; Memory comprising one or more storage media for storing instructions; and It includes at least one processor comprising a processing circuit, and When the above instructions are executed individually or collectively by the at least one processor, the communication device: Based on the first location information of the communication device, time synchronization information obtained using the transceiver, and orbit information of the satellites obtained using the transceiver, reference coordinate information of the satellites is obtained, and Based on the target GNSS signal received using the above receiver, coordinate information of the target satellite indicated by the target GNSS signal among the above satellites is obtained, and Based on the reference coordinate information and the coordinate information, it is determined whether the target GNSS signal is a normal signal transmitted from the target satellite or a spoofing signal not transmitted from the target satellite, and Based on the determination that the target GNSS signal is the normal signal, second position information of the communication device is calculated using the target GNSS signal, and Causing to refrain from calculating the second position information of the communication device using the target GNSS signal based on the determination that the target GNSS signal is the spoofing signal, Communication device.

2. In Claim 1, The above reference coordinate information includes the reference coordinates of the target satellite relative to the communication device, and The above coordinate information includes the coordinates of the target satellite relative to the communication device, and When the above instructions are executed individually or collectively by the at least one processor, the communication device: Based on the determination that the distance between the above reference coordinates and the above coordinates is smaller than the reference distance, the target GNSS signal is determined as the normal signal, and Causing the target GNSS signal to be determined as the spoofing signal based on the determination that the distance between the above reference coordinate and the above coordinate is not smaller than the above reference distance, Communication device.

3. In Claim 1, The above reference coordinate information includes the reference elevation angle of the target satellite relative to the communication device, and When the above instructions are executed individually or collectively by the at least one processor, the communication device: Causing the target GNSS signal to be determined as the spoofing signal based on the determination that the above reference elevation angle is smaller than the reference angle corresponding to the horizon for the position of the communication device, Communication device.

4. In Claim 1, When the above instructions are executed individually or collectively by the at least one processor, the communication device: Based on the determination that the above target GNSS signal is the normal signal, time information is obtained using the above target GNSS signal, and Causing to refrain from acquiring time information using the target GNSS signal based on the determination that the target GNSS signal is the spoofing signal, Communication device.

5. In Claim 4, When the above instructions are executed individually or collectively by the at least one processor, the communication device: Based on the determination that the above target GNSS signal is the above normal signal: Identify the time offset between the above-mentioned acquired time information and other time information applied to the communication device, and Based on identifying the time offset greater than the reference offset, time synchronization is performed using the time synchronization information, and Based on identifying the time offset smaller than the reference offset, causing the other time information applied to the communication device to be maintained, Communication device.

6. In Claim 1, When the above instructions are executed individually or collectively by the at least one processor, the communication device: Based on the determination that the above target GNSS signal is the above normal signal: Identifying the distance between the first coordinates represented by the first position information and the second coordinates represented by the second position information, Based on identifying the above distance which is greater than the reference distance, the occurrence of an error in the above first location information of the communication device is identified, and Causing to maintain the first position information of the communication device based on identifying the distance smaller than the reference distance above, Communication device.

7. In Claim 1, The above time synchronization information is received through the transceiver from at least one of a PTP (precision time protocol) server or an NTP (network time protocol) server, Communication device.

8. In Claim 1, The orbital information of the above satellites is received through the transceiver from an A-GNSS (assisted-GNSS) server configured to assist GNSS, Communication device.

9. A method performed in a communication device having a transceiver for communicating with a terrestrial network element (NE) and a receiver configured to receive a global navigation satellite system (GNSS) signal, wherein The operation of obtaining reference coordinate information of the satellites based on the first location information of the communication device, time synchronization information obtained using the transceiver, and orbit information of the satellites obtained using the transceiver, An operation of acquiring coordinate information of a target satellite indicated by the target GNSS signal among the satellites, based on a target GNSS signal received using the receiver, An operation to determine whether the target GNSS signal is a normal signal transmitted from the target satellite or a spoofing signal not transmitted from the target satellite, based on the above reference coordinate information and the above coordinate information. An operation of calculating second position information of the communication device using the target GNSS signal according to the determination that the target GNSS signal is the normal signal, and Includes an operation of refraining from calculating the second position information of the communication device using the target GNSS signal based on the determination that the target GNSS signal is the spoofing signal. method.

10. In Claim 9, The above reference coordinate information includes the reference coordinates of the target satellite relative to the communication device, and The above coordinate information includes the coordinates of the target satellite relative to the communication device, and The above method is, An operation of determining the target GNSS signal as the normal signal based on the determination that the distance between the above reference coordinates and the above coordinates is smaller than the reference distance, and The operation of determining the target GNSS signal as the spoofing signal based on the determination that the distance between the reference coordinate and the coordinate is not smaller than the reference distance, method.

11. In Claim 9, The above reference coordinate information includes the reference elevation angle of the target satellite relative to the communication device, and The above method is, The operation of determining the target GNSS signal as the spoofing signal based on the determination that the reference elevation angle is smaller than the reference angle corresponding to the horizon for the position of the communication device. method.

12. In Claim 9, An operation to acquire time information using the target GNSS signal based on the determination that the target GNSS signal is the normal signal, and Further including the operation of refraining from acquiring time information using the target GNSS signal based on the determination that the target GNSS signal is the spoofing signal. method.

13. In Claim 12, Based on the determination that the above target GNSS signal is the above normal signal: An operation to identify a time offset between the above-mentioned acquired time information and other time information applied to the communication device, An operation of performing time synchronization using the time synchronization information based on identifying the time offset greater than the reference offset, and Based on identifying the time offset smaller than the reference offset, the operation of maintaining the other time information applied to the communication device further includes method.

14. In Claim 9, Based on the determination that the above target GNSS signal is the above normal signal: An operation to identify the distance between the first coordinates represented by the first position information and the second coordinates represented by the second position information, An operation to identify the occurrence of an error in the first position information of the communication device based on identifying the above distance which is greater than a reference distance, and The operation of maintaining the first position information of the communication device based on identifying the distance smaller than the reference distance, further comprising method.

15. In Claim 9, The above time synchronization information is received through the transceiver from at least one of a PTP (precision time protocol) server or an NTP (network time protocol) server, method.

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