Navigation signal authentication method based on composite code shift keying signal, network device, terminal device, chip, computer readable storage medium and computer program product

Abstract

The invention provides a navigation signal authentication method based on a composite code shift keying signal, network equipment, terminal equipment, a chip, a computer readable storage medium and a computer program product, and relates to the technical field of navigation signal processing. The navigation signal authentication method based on the composite code-shift keying signal comprises the following steps: generating a code-shift keying code based on a spreading code parameter; replacing a target chip in a code shift keying code period in the authentication period with the encryption code to obtain an encrypted code shift keying code; generating a digital signature based on the target message in the authentication period; an authentication message is generated, the authentication message comprises navigation message authentication information and spreading code authentication information, the navigation message authentication information is used for digital signature authentication, and the spreading code authentication information is used for spreading code authentication; modulating a high-speed message of the authentication message and the navigation message based on the encrypted code-shift keying code, modulating a low-speed message of the navigation message through binary phase shift keying, and generating a composite code-shift keying signal; and broadcasting the composite code shift keying signal.

Description

Technical Field

[0001] The present disclosure relates to the technical field of navigation signal processing, and in particular to a navigation signal authentication method based on a composite code shift keying signal, a network device, a terminal device, a chip, a computer-readable storage medium, and a computer program product. Background Art

[0002] Navigation signal authentication refers to the use of encryption features to combat spoofing and provide navigation signal authentication services. Authentication refers to verifying the authenticity of the signal and the entity sending the information (i.e. entity authentication and data source authentication). Authentication can work at the level of satellite ephemeris broadcast in navigation messages, or at the level of spread spectrum codes used for ranging, both of which are modulated into the Global Navigation Satellite System (GNSS) signal.

[0003] Current authentication technologies include navigation message authentication (NMA) and spreading code authentication (SCA). Navigation message authentication means protecting the navigation message bits (i.e. the entire data frame or some bits). Navigation message authentication can be achieved by digitally signing the navigation data, thus keeping the navigation message clean (i.e. unencrypted) and usable by non-authenticated users. Spreading code authentication inserts unpredictable parts (i.e. encrypted chips) into the nominal (unencrypted) spreading code, which is then verified by a cryptographic function.

[0004] Navigation message authentication is only an authentication at the information level. In theory, a cheater can demodulate the message and modify the signal by regenerating it to cheat. Therefore, the anti-cheating capability is average. Spread spectrum code authentication is an authentication at the signal level. The information and signal are bound and cannot be modified. Therefore, the security level is higher. Summary of the invention

[0005] In view of this, a navigation signal authentication method based on a composite code shift keying signal, a network device, a terminal device, a chip, a computer-readable storage medium and a computer program product are provided.

[0006] In a first aspect, a navigation signal authentication method based on a composite code shift keying signal is provided, comprising: Based on the spread spectrum code parameters, a code shift keying code is generated; Using the encryption code to replace the target code chip in the code shift keying code period in the authentication period to obtain the encrypted code shift keying code; Generate a digital signature based on the target electronic message within the authentication period; generating an authentication message, wherein the authentication message includes navigation message authentication information and spread spectrum code authentication information, wherein the navigation message authentication information is used for digital signature authentication, and the spread spectrum code authentication information is used for spread spectrum code authentication; Modulating the high-speed message of the authentication message and the navigation message based on the encrypted code shift keying code, and modulating the low-speed message of the navigation message by binary phase shift keying to generate a composite code shift keying signal; The composite code shift keying signal is broadcasted.

[0007] In a second aspect, a navigation signal authentication method based on a composite code shift keying signal is provided, comprising: receiving a composite code shift keying signal; Demodulating the composite code shift keying signal to obtain an authentication message; The digital signature is authenticated based on the navigation message authentication information in the authentication message, and the spread spectrum code is authenticated based on the spread spectrum code authentication information in the authentication message.

[0008] In a third aspect, a satellite network device is provided, which includes: one or more processors; and one or more memories coupled to the one or more processors and storing instructions thereon, wherein when the instructions are executed by the one or more processors individually or collectively, the satellite network device executes the method described in the first aspect.

[0009] In a fourth aspect, a terminal device is provided. The terminal device includes: one or more processors; and one or more memories coupled to the one or more processors and storing instructions thereon. When the instructions are executed by the one or more processors individually or collectively, the terminal device executes the method described in the second aspect.

[0010] According to a fifth aspect, a chip is provided, wherein the chip includes a circuit system configured to execute the method according to the first aspect or the second aspect.

[0011] In a sixth aspect, a non-transitory computer-readable storage medium storing machine-executable instructions is provided. When the machine-executable instructions are executed by one or more processors of a machine, the machine executes the method of the first aspect or the second aspect.

[0012] In a seventh aspect, a computer program product comprising machine executable instructions is provided. When the machine executable instructions are executed by one or more processors of a machine, the machine executes the method of the first aspect or the second aspect.

[0013] It should be understood that the invention summary is not intended to identify the key or essential features of the embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The above and other objects, features and advantages of the present disclosure will become more apparent through a more detailed description of some embodiments of the present disclosure in the accompanying drawings, in which: Figure 1 illustrates an exemplary communication network in which exemplary embodiments of the present disclosure may be implemented; Figure 2 A schematic diagram showing the structure of a composite code shift keying signal according to some embodiments of the present disclosure is shown; Figure 3 A flowchart showing an exemplary method of navigation signal authentication based on a composite code shift keying signal according to some embodiments of the present disclosure is shown; Figure 4 A flowchart showing an exemplary method of composite code shift keying signal generation according to some embodiments of the present disclosure is shown; Figure 5 A schematic diagram showing the structure of navigation message authentication information of an authentication message according to some embodiments of the present disclosure is shown; Figure 6 A schematic diagram showing the structure of spread spectrum code authentication information of an authentication message according to some embodiments of the present disclosure is shown; Figure 7 A schematic diagram showing the structure of a composite code shift keying signal according to some embodiments of the present disclosure is shown; Figure 8 A flowchart illustrating an exemplary method of composite code shift keying signal authentication according to some embodiments of the present disclosure is shown; Fig. 9 A simplified block diagram of a device suitable for implementing the exemplary embodiments of the present disclosure is shown. DETAILED DESCRIPTION

[0015] The principle of the present disclosure will now be described with reference to some embodiments. It should be understood that the description of these embodiments is only for illustrative purposes, and helps those skilled in the art to understand and implement the present disclosure, without any limitation to the scope of the present disclosure. The disclosure described herein can be implemented in a manner different from that described below.

[0016] In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0017] References in this disclosure to "one embodiment," "an embodiment," "an exemplary embodiment," etc. indicate that the described embodiment may include a particular feature, structure, or characteristic, but not every embodiment necessarily includes the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. In addition, when a particular feature, structure, or characteristic is described in conjunction with an exemplary embodiment, whether or not explicitly described, those skilled in the art will recognize that such feature, structure, or characteristic affects incorporation into other embodiments.

[0018] It should be understood that although the terms "first" and "second" etc. may be used to describe various elements herein, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, without departing from the scope of the exemplary embodiments, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element. The term "and / or" as used herein includes any and all combinations of one or more of the listed terms.

[0019] The terms used herein are only for describing specific embodiments, rather than for limiting exemplary embodiments. The singular forms "one", "an", and "the" used herein also include plural forms, unless the context clearly indicates otherwise. "A group of elements" or "element set" used herein is intended to include one or more elements. It should also be understood that the terms "include", "comprise", "have", "have", "include" and / or "include", when used herein, specify the presence of the features, elements and / or parts, etc., but do not exclude the presence or addition of one or more other features, elements, parts and / or combinations thereof.

[0020] As used herein, the term "circuitry" may refer to one or more or all of the following: (a) Hardware circuit implementation only (e.g., implementation only in analog and / or digital circuits) (b) a combination of hardware circuitry and software, such as (where applicable): (i) a combination of analog and / or digital hardware circuitry and software / firmware; and (ii) any part of a hardware processor (including a digital signal processor) with software, software and memory that work together to enable a device such as a mobile phone or server to perform various functions, and (c) A hardware circuit and / or processor, such as a microprocessor or portion of a microprocessor, that requires software (eg, firmware) to operate, but where software is not required for operation, the software may not be present.

[0021] This definition of circuitry applies to all uses of this term in this application, including in any claims. As another example, as used in this application, the term circuitry also includes an implementation of merely a hardware circuit or processor (or multiple processors) or a portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware. The term circuitry also includes, for example, if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device, or a similar integrated circuit in a server, cellular network device, or other computing network device.

[0022] The term "communication network" refers to a network that complies with any appropriate communication standard, such as Long Term Evolution (LTE), LTE-Advanced (LTE-A), Wideband Code Division Multiple Access (WCDMA), High Speed ​​Packet Access (HSPA), Narrowband Internet of Things (NB-IoT), New Radio (NR), Non-Terrestrial Network (NTN), etc. In addition, the communication between the terminal equipment and the network equipment in the communication network can be performed according to any appropriate generation of communication protocols, including but not limited to the first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, fifth generation (5G), future sixth generation (6G) communication protocols, and / or any other protocols currently known or to be developed in the future. The embodiments of the present disclosure can be applied in satellite communication systems. In view of the rapid development in communication, there will certainly be future types of communication technologies and systems, and the present disclosure can be implemented with these technologies and systems. It should not be considered that the scope of the present disclosure is limited to the aforementioned system.

[0023] The term "satellite network equipment" refers to a node set up on a satellite or ground segment in a satellite communication network. The terminal device accesses the network through this node and receives services from it. Depending on the terminology and technology applied, satellite network equipment can refer to a base station (BS) or access point (AP) as a satellite payload, such as NodeB (NodeB or NB), evolved NodeB (eNodeB or eNB), NR NB (also known as gNB), remote radio unit (RRU), radio head (RH), remote radio head (RRH), relay node. An example of a relay node may be an integrated access and backhaul (IAB) node. The distributed unit (DU) part of the IAB node can perform the functions of a "satellite network equipment" and can therefore operate as a network device. In the following description, the terms "satellite network equipment", "BS" and "node" can be used interchangeably.

[0024] The term "terminal device" refers to any terminal device capable of wireless communication. As an example and not a limitation, a terminal device may also be referred to as a communication device, a user equipment (UE), a user station (SS), a portable user station, a mobile station (MS), or an access terminal (AT). The terminal device may include, but is not limited to, a mobile phone, a cellular phone, a smart phone, a voice over IP (VoIP) phone, a wireless local loop phone, a tablet computer, a wearable terminal device, a personal digital assistant (PDA), a portable computer, a desktop computer, an image capture terminal device such as a digital camera, a game terminal device, a music storage and playback device, a vehicle-mounted wireless terminal device, a wireless endpoint, a mobile station, a notebook embedded device (LEE), a laptop mounted device (LME), a USB dongle, a smart device, a wireless user equipment (CPE), an Internet of Things (IoT) device, a watch or other wearable device, a head mounted display (HMD), a vehicle, a drone, medical equipment and applications (e.g., remote surgery), industrial equipment and applications (e.g., robots and / or other wireless devices operating in the context of an industrial and / or automated processing chain), consumer electronic devices, relay nodes, devices operating on commercial and / or industrial wireless networks, etc. The mobile terminal (MT) part of the IAB node can perform the functions of a "terminal device" and can therefore operate as a terminal device. In the following description, the terms "terminal device", "communication device", "terminal", "user equipment" and "UE" can be used interchangeably.

[0025] Although the functions described herein may be performed in fixed and / or wireless network nodes in various exemplary embodiments, in other exemplary embodiments, the functions may be implemented in a user equipment device (such as a cellular phone, or a tablet computer, or a laptop computer, or a desktop computer, or a mobile Internet of Things device, or a fixed Internet of Things device). For example, the user equipment device may appropriately have the corresponding capabilities described in relation to fixed and / or wireless network nodes. The user equipment device may be a user device and / or a control device, such as a chipset or a processor, which is configured to control the user device when the user device is installed therein. Examples of these functions include boot server functions and / or home user servers, which may be implemented in a user equipment device by providing the user equipment device with software configured to cause the user equipment device to execute from the perspective of these functions / nodes.

[0026] Figure 1An exemplary communication network 100 in which embodiments of the present disclosure may be implemented is shown. The communication network 100 includes a satellite network device 110 and a terminal device 120 served by the satellite network device 110. The satellite network device 110 may include satellite network devices 110A, 110B, and 110C, and the terminal device 120 may include terminal devices 120A and 120B. The communication network 100 may provide a service cell 130 to serve the terminal device 120. The satellite communication network may include a low-orbit satellite (LEO), a medium-orbit satellite (MEO), and a geosynchronous orbit satellite (GEO).

[0027] It should be understood that the number of satellite network devices 110, terminal devices 120, and service cells 130 is for illustrative purposes only and is not intended to impose any limitation. Communication network 100 may include any appropriate number of satellite network devices, terminal devices, and service cells suitable for implementing embodiments of the present disclosure. It should be noted that the terms "cell" and "service cell" are used interchangeably herein.

[0028] In the communication network 100, the satellite network device 110 can transmit data and control information to the terminal device 120, and the terminal device 120 can also transmit data and control information to the satellite network device 110. The link from the satellite network device 110 to the terminal device 120 is called a downlink (DL) or a forward link, and the link from the terminal device 120 to the satellite network device 110 is called an uplink (UL) or a reverse link. The satellite network device 110 can broadcast a navigation message to the terminal device 120, and the terminal device 120 implements functions such as navigation positioning based on the received navigation message.

[0029] The communication in the communication network 100 may conform to any suitable standard, but is not limited to Long Term Evolution (LTE), LTE Evolution, LTE-Advanced (LTE-A), Wideband Code Division Multiple Access (WCDMA), Code Division Multiple Access (CDMA), and Global System for Mobile Communications (GSM). In addition, the communication may be performed according to any generation of communication protocols currently known or developed in the future. Examples of communication protocols include, but are not limited to, first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, fifth generation (5G), and sixth generation (6G) communication protocols.

[0030] The navigation message is a message broadcasted by the navigation satellite to the user describing the operating status parameters of the navigation satellite, including the time scale information, ephemeris parameters, clock error parameters, satellite status parameters, almanac parameters, ionosphere parameters, etc. of the navigation satellite itself. In some embodiments, the navigation message includes a low-speed message and a high-speed message. The low-speed message includes basic navigation information for measurement with a slow update speed, such as the time scale information, ephemeris parameters, clock error parameters, satellite status parameters, almanac parameters, ionosphere parameters, etc. of the navigation satellite itself. The high-speed message includes navigation enhancement information with a fast update speed, such as the orbit, carrier phase deviation and code deviation of the entire navigation satellite system.

[0031] When generating the navigation signal, the low-speed message of the navigation message can be modulated by binary phase shift keying (BPSK) to form a BPSK code cycle, and the high-speed message of the navigation message can be modulated by code shift keying (CSK) to form a CSK code cycle. The BPSK code cycle and the CSK code cycle are arranged alternately to form a composite code shift keying (MCSK) signal 200, such as Figure 2 shown.

[0032] Existing navigation signal authentication is designed for GNSS signals and cannot be directly applied to MCSK signals of low-orbit satellites. The disclosed embodiment proposes a navigation signal authentication method based on MCSK signals to achieve navigation signal authentication of MCSK signals, and combines navigation message authentication and spread spectrum code authentication to achieve second-level signal authentication.

[0033] Figure 3 FIG. 1 is a flow chart of a navigation signal authentication method based on a composite code shift keying signal according to some embodiments of the present disclosure. Figure 3 As shown, the navigation signal authentication method 300 based on the composite code shift keying signal includes the following steps: Step S301: generating a composite code shift keying signal.

[0034] The composite code shift keying signal generation stage includes generating a CSK code, encrypting a spread spectrum code, generating a digital signature, generating an authentication message, generating a composite code shift keying signal, and broadcasting the composite code shift keying signal.

[0035] Step S302: Composite code shift keying signal authentication.

[0036] In the composite code shift keying signal authentication stage, after the terminal device 120 (such as a receiver in the terminal device 120 ) tracks the demodulation synchronization, digital signature authentication and spread spectrum code authentication are performed.

[0037] The disclosed embodiment performs dual authentication at the information level and the signal level, and can achieve second-level authentication of MCSK signals without losing measurement accuracy.

[0038] Now refer to Figure 4 . Figure 4 4 is a flow chart showing an exemplary method 400 for generating a composite code shift keying signal according to some embodiments of the present disclosure. The method 400 may be implemented on a device, such as Figure 1 The satellite network device 110 is shown. For the purpose of discussion, reference will be made to Figure 1 Method 400 is described. Method 400 may involve Figure 1 Satellite network device 110 and terminal devices 120A and 120B are shown. It should be understood that method 400 may include additional steps not shown and / or may omit some of the steps shown, and the scope of the present disclosure is not limited in this regard.

[0039] In step S401, a code shift keying code is generated based on a spread spectrum code parameter.

[0040] In step S402, the encryption code is used to replace the target code chip in the code shift keying code period in the authentication period to obtain an encrypted code shift keying code.

[0041] In some embodiments, the target code chip is a code chip at a target position of a target code shift keying code period within a target time period in an authentication period, the target code shift keying code period is one or more code shift keying code periods, and the target position is one or more continuous code chip positions.

[0042] In an exemplary embodiment, let the authentication period be T seconds, and encrypt part of the code chips in at least part of the CSK code period in the last 1 second of each authentication period T. Specifically, select N in the CSK code period in the last 1 second of the authentication period T. period code period, the N period The code period is the target code shift keying code period. Use the encryption code to replace this N period The last N code cycles chip chips, that is, there are N chip_total =N period ×N chip The chips are encrypted. period The position of each code period can be given through the authentication message, or it can be the default position of the network system. chip_total 、N period and N chip The choice can be determined according to the required encryption strength. The larger the value, the higher the encryption strength.

[0043] In the above embodiment, the last 1s of the authentication cycle T is the target time period, and the last N of the code cycle chipThe position of the code piece is the target position. It can be understood that the target code shift keying code period can be selected in other time periods in the authentication period T, and the code pieces at other positions of the target code shift keying code period can also be replaced with encryption codes. The target time period and the target position can both be the default values ​​of the network system, or can be given through the authentication message.

[0044] In some embodiments, the encryption code generation method includes: selecting an encryption code generation phase from a message digest in a digital signature generation process; and generating an encryption code based on an encryption code generation polynomial and the encryption code generation phase.

[0045] In an exemplary embodiment, N is generated based on the encryption code generating polynomial and the encryption code generating initial phase. chip_total The encryption code of chips is evenly divided into N period Each copy has N chip chips to replace the selected N period The last N CSK code cycles chip In the last second of each authentication cycle of T seconds, the CSK code cycle is counted. If the current CSK code cycle belongs to the code cycle of the encryption code position, N chip The encryption code of the code chips replaces the last N of the CSK code cycle chip A code chip.

[0046] The initial phase of encryption code generation can be selected from HASH-A, so that the spread spectrum code authentication is bound to the navigation message authentication. Among them, HASH-A is the message digest of the target message within the authentication period mapped by the hash (HASH) algorithm. For example, HASH-A is the 256-bit message digest of the target message mapped by the HASH algorithm. The initial phase of encryption code generation can select the first 32 bits of the 256 bits of HASH-A, 1-16 bits as the first phase of generating a multi-phase formula, and 17-32 bits as the second phase of generating a multi-phase formula. Since HASH-A is bound to the digital signature of the navigation message authentication, N chip_total The value of the encryption code is bound to the navigation message authentication, so the spread spectrum code authentication is bound to the navigation message authentication.

[0047] In step S403, a digital signature is generated based on the target electronic message within the authentication period.

[0048] In some embodiments, generating a digital signature based on a target message within an authentication cycle includes: mapping the target message within the authentication cycle to a message digest through a hash (HASH) algorithm; encrypting the message digest using an asymmetric encryption algorithm to generate a digital signature. The target message may include time stamp information, ephemeris parameters and clock error parameters of a low-speed message, as well as some high-speed messages. An asymmetric encryption algorithm, such as the ECDSA encryption algorithm, is used to perform navigation message authentication on the time stamp information, ephemeris parameters and clock error parameters of a low-speed message, as well as some high-speed messages, with each T seconds being an authentication cycle, thereby improving security and reducing computational complexity.

[0049] In an exemplary embodiment, the target message N within the authentication period (such as the time stamp information, ephemeris parameters and clock error parameters of the low-speed message, and some high-speed messages) is mapped to a 256-bit message digest through the HASH algorithm, recorded as HASH-A. Combined with the private key d and HASH-A, the ECDSA encryption algorithm is used to generate a digital signature pair (r, s). The disclosed embodiment uses the ECDSA encryption algorithm. When the timing accuracy is ( is the user’s time estimation error), the ECDSA encryption algorithm can ensure authentication security.

[0050] In step S404, an authentication message is generated.

[0051] The authentication message is similar to the high-speed message, and the channel coding scheme is the same. An authentication message is broadcast every authentication period of T seconds. The authentication message includes navigation message authentication information and spread spectrum code authentication information, where the navigation message authentication information is used for digital signature authentication, and the spread spectrum code authentication information is used for spread spectrum code authentication. In some embodiments, the spread spectrum code authentication information indicates the encryption code position, such as the position of the target code shift keying code period, etc. The structure of the authentication message is as follows: Figure 5-Figure 6 As shown, Figure 5 A schematic diagram showing the structure of navigation message authentication information of an authentication message according to some embodiments of the present disclosure is shown. Figure 6 A schematic diagram of the structure of spread spectrum code authentication information of an authentication message according to some embodiments of the present disclosure is shown.

[0052] In step S405, the high-speed messages of the authentication message and the navigation message are modulated based on the encrypted code shift keying code, and the low-speed message of the navigation message is modulated by binary phase shift keying to generate a composite code shift keying signal.

[0053] The encrypted CSK code is used for spread spectrum, and the authentication message is channel-coded to generate an MCSK signal 600, such as Figure 7The spread spectrum code authentication of the embodiment of the present disclosure is only performed in the CSK code period in the MCSK signal 600, and the BPSK code period in the MCSK signal 600 is used for measurement, which does not affect the measurement performance.

[0054] Compared with the existing MCSK signal, the CSK code period only uses the code shift phase modulation message. The disclosed embodiment uses the reserved information broadcasting capability of the MCSK signal and uses the code period polarity modulation authentication message reserved by the CSK code period to effectively support the additional broadcasting requirements such as digital signatures and keys required for signal authentication.

[0055] In step S406, a composite code shift keying signal is broadcast.

[0056] Tracking the main spreading sequence of users, in N period There is a small correlation loss in the CSK code period (for example, the CSK code length is 2046 chips and N chip =200, the loss is less than 0.9 dB), which can be compensated by increasing the average transmission power. Since some code chips are encrypted, for non-authenticated users, the original spread spectrum code series is still used, which is related to the authentication signal, and the related power will be reduced. Therefore, in order to ensure that the related power of unauthorized users remains unchanged, the spread spectrum code authentication signal needs to increase the signal transmission power.

[0057] In an exemplary embodiment, let the authentication period be T=10s, the CSK code rate be 5.115MHz, and the code length be 2046Chip. In the spread spectrum code encryption stage, the CSK code period of the last 1s in each authentication period of 10s is encrypted. For example, N of the 2500 CSK code periods in the last 1s are encrypted. period = the last N of 30 code cycles chip = 200 chips are replaced by encryption chips, that is, only N period ×N chip = 6000 chips are encrypted. period The impact of demodulation of a CSK code period is: , which only leads to N period The loss of each CSK code cycle is less than 0.9dB.

[0058] Now refer to Figure 8 . Figure 8 Flowchart showing an exemplary method 700 for composite code shift keying signal authentication according to some embodiments of the present disclosure. The method 700 may be implemented on a device, such as Figure 1 For the purpose of discussion, reference will be made to the terminal device 120. Figure 1 Method 700 is described. Method 700 may involve Figure 1Satellite network device 110 and terminal devices 120A and 120B are shown. It should be understood that method 700 may include additional steps not shown and / or may omit some of the steps shown, and the scope of the present disclosure is not limited in this regard.

[0059] In step S701, a composite code shift keying signal is received.

[0060] In step S702, the composite code shift keying signal is demodulated to obtain an authentication message.

[0061] The terminal device 120 receives the MCSK signal, tracks the demodulation, and obtains the authentication message after bit synchronization. The authentication message includes navigation message authentication information and spread spectrum code authentication information, wherein the navigation message authentication information is used for digital signature authentication, and the spread spectrum code authentication information is used for spread spectrum code authentication. In some embodiments, demodulating the composite code shift keying signal includes: demodulating the high-speed message data and authentication message data in the composite code shift keying signal according to the code shift keying mode, and demodulating the low-speed message data in the composite code shift keying signal according to the binary phase shift keying mode.

[0062] In step S703, the digital signature is authenticated based on the navigation message authentication information in the authentication message, and the spread spectrum code is authenticated based on the spread spectrum code authentication information in the authentication message.

[0063] The process of digital signature authentication includes: using the public key to decrypt, and if the signature is verified correctly, it means the authentication is successful. Q ,y Q ) can be obtained through a trusted authentication center. It is set when the terminal leaves the factory and can be obtained through the network later or updated by receiving an authentication telegram frame.

[0064] In some embodiments, authenticating the spread spectrum code based on the spread spectrum code authentication information in the authentication message includes: obtaining a first chip correlation value corresponding to a target chip in a code shift keying code period in an authentication cycle of a composite code shift keying signal; generating an encryption chip based on the spread spectrum code authentication information in the authentication message, and obtaining a corresponding second chip correlation value; correlating the first chip correlation value with the second chip correlation value to obtain a correlation result; in response to the correlation result being greater than a threshold value, the authentication is successful, otherwise the authentication fails. Wherein, the target chip is a chip at a target position of a target code shift keying code period in a target time period in the authentication cycle, the target code shift keying code period is one or more code shift keying code periods, and the target position is one or more continuous chip positions. In some embodiments, the position of the target code shift keying code period can also be obtained based on the spread spectrum code authentication information in the authentication message.

[0065] In an exemplary embodiment, the last N of the target CSK code period in the last 1s of each authentication period T are chipThe baseband sample chip correlation value (i.e., the first chip correlation value) corresponding to the chip is stored. Generate N chip_total According to the 24 encryption code positions, select the corresponding N chip_total chip correlation value (i.e., the second chip correlation value), and N chip_total The first code chip correlation value is correlated to obtain a correlation result, which is compared with the threshold value TH. If it is greater than the threshold value, the authentication is successful, otherwise it fails. Among them, TH can be obtained according to the false alarm probability or set as needed. The correlation value here refers to the I and Q code chip correlation value stripped from the authentication message.

[0066] Fig. 9 8 is a simplified block diagram of a device 800 suitable for implementing an embodiment of the present disclosure. For example, the satellite network device 110 and / or the terminal device 120 may be implemented by the device 800. As shown, the device 800 includes one or more processors 810, one or more memories 820 coupled to the processor 810, and one or more communication modules 840 coupled to the processor 810.

[0067] The communication module 840 is used for two-way communication. The communication module 840 has at least one antenna to facilitate communication. The communication interface may represent any interface necessary for communicating with other network elements.

[0068] Processor 810 may be of any type suitable for the local technology network, and may include, as non-limiting examples, one or more of: a general purpose computer, a special purpose computer, a microprocessor, a digital signal processor (DSP), and a processor based on a multi-core processor architecture. Device 800 may have multiple processors, such as application specific integrated circuit chips, which are driven in time to a clock that synchronizes a master processor.

[0069] The memory 820 may include one or more non-volatile memories and one or more volatile memories. Examples of non-volatile memories include, but are not limited to, read-only memory (ROM) 824, electrically programmable read-only memory (EPROM), flash memory, hard disk, compact disk (CD), digital video disk (DVD), and other magnetic and / or optical memories. Examples of volatile memories include, but are not limited to, random access memory (RAM) 822 and other volatile memories that do not persist during a power outage.

[0070] The computer program 830 includes computer executable instructions that are executed by the associated processor 810. The program 830 may be stored in the ROM 824. The processor 810 may perform any appropriate actions and processes by loading the program 830 into the RAM 822.

[0071] The embodiments of the present disclosure may be implemented by a program 830, so that the device 800 may execute the reference Figure 3 and Figure 4 and Figure 8 Any process of the disclosure discussed. The embodiments of the present disclosure may also be implemented by hardware or by a combination of software and hardware.

[0072] In some embodiments, the program 830 may be tangibly contained in a computer-readable medium, which may be contained in the device 800 (e.g., memory 820) or other storage devices accessible to the device 800. The device 800 may load the program 830 from the computer-readable medium to the RAM 822 for execution. The computer-readable medium may include any type of tangible non-volatile memory, such as ROM, EPROM, flash memory, hard disk, CD, DVD, etc. The computer-readable medium has the program 830 stored thereon.

[0073] Generally, various embodiments of the present disclosure may be implemented in hardware or dedicated circuits, software, logic, or any combination thereof. Certain aspects may be implemented in hardware, while other aspects may be implemented in firmware or software, which may be executed by a controller, microprocessor, or other computing device. Although various aspects of the embodiments of the present disclosure are shown and described as block diagrams, flow charts, or using some other graphical representations, it should be understood that, as non-limiting examples, the blocks, devices, systems, techniques, or methods described herein may be implemented in hardware, software, firmware, dedicated circuits or logic, general hardware or controllers or other computing devices, or some combination thereof.

[0074] The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer executable instructions, such as instructions included in program modules, which are executed in a device on a target real or virtual processor to perform the above-mentioned reference Figure 3 The method 300, and / or the above-mentioned reference Figure 4 The method 400, and / or the above-mentioned reference Figure 8 The method 700 described. Typically, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform specific tasks or implement specific abstract data types. In various embodiments, the functions of program modules can be combined or separated between program modules as needed. Machine executable instructions for program modules can be executed in local or distributed devices. In distributed devices, program modules can be located in local and remote storage media.

[0075] The program code for executing the disclosed method can be written in any combination of one or more programming languages. These program codes can be provided to a processor or controller of a general-purpose computer, a special-purpose computer or other programmable data processing equipment so that when the program code is executed by the processor or controller, the function / operation specified in the flow chart and / or block diagram is realized. The program code can be executed completely on the machine as an independent software package, partially on the machine, partially on the machine, partially on a remote machine, partially on a remote machine, or all on a remote machine or server.

[0076] In the context of the present disclosure, computer program codes or related data may be carried by any appropriate carrier to enable a device, apparatus or processor to perform various processes and operations as described above. Examples of carriers include signals, computer readable media, etc.

[0077] The computer readable medium may be a computer readable signal medium or a computer readable storage medium. The computer readable medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared or semiconductor systems, devices or apparatuses, or any suitable combination of the foregoing. More specific examples of computer readable storage media include an electrical connection having one or more conductors, a portable computer floppy disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0078] In addition, although the operations are described in a specific order, this should not be understood as requiring the specific order or sequence shown to be performed, or performing all the operations shown, to obtain the desired result. In some cases, multitasking and parallel processing may be advantageous. Similarly, although several specific implementation details are included in the above discussion, these details should not be interpreted as limitations on the scope of the present disclosure, but can be interpreted as descriptions of features specific to a particular embodiment. Certain features described in the context of a separate embodiment may also be implemented in combination in a single embodiment. On the contrary, the various features described in the context of a single embodiment may also be implemented in multiple embodiments individually or in any suitable sub-combination.

[0079] Although the disclosure has been described in language specific to structural features and / or methodological acts, it should be understood that the disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

[0080] It should be fully understood that the use of personally identifiable information should be subject to privacy policies and practices generally recognized as meeting or exceeding industry or government requirements for maintaining user privacy. In particular, personally identifiable information data should be managed and processed to minimize the risk of inadvertent or unauthorized access or use, and the nature of authorized use should be clearly indicated to users.

Claims

1. A navigation signal authentication method based on a composite code shift keying signal, characterized in that: include: Based on the spread spectrum code parameters, a code shift keying code is generated; Using the encryption code to replace the target code chip in the code shift keying code period in the authentication period to obtain the encrypted code shift keying code; Generate a digital signature based on the target electronic message within the authentication period; generating an authentication message, wherein the authentication message includes navigation message authentication information and spread spectrum code authentication information, wherein the navigation message authentication information is used for digital signature authentication, and the spread spectrum code authentication information is used for spread spectrum code authentication; Modulating the high-speed message of the authentication message and the navigation message based on the encrypted code shift keying code, and modulating the low-speed message of the navigation message by binary phase shift keying to generate a composite code shift keying signal; The composite code shift keying signal is broadcasted.

2. The method according to claim 1, characterized in that The target code chip is a code chip at a target position of a target code shift keying code period within a target time period in the authentication period, the target code shift keying code period is one or more code shift keying code periods, and the target position is one or more continuous code chip positions.

3. The method according to claim 1 or 2, characterized in that The generating of a digital signature based on a target electronic message within the authentication period comprises: Mapping the target electronic message within the authentication period into a message digest through a hash algorithm; The message digest is encrypted using an asymmetric encryption algorithm to generate a digital signature.

4. The method according to claim 3, characterized in that Also includes: Selecting an encryption code from the message digest to generate an initial phase; The encryption code is generated based on an encryption code generating polynomial and the encryption code generating initial phase.

5. The method according to claim 3, characterized in that The target message includes the time stamp information, ephemeris parameters and clock error parameters of the low-speed message, and part of the high-speed message.

6. A navigation signal authentication method based on a composite code shift keying signal, characterized in that: include: receiving a composite code shift keying signal; Demodulating the composite code shift keying signal to obtain an authentication message; The digital signature is authenticated based on the navigation message authentication information in the authentication message, and the spread spectrum code is authenticated based on the spread spectrum code authentication information in the authentication message.

7. The method according to claim 6, characterized in that The authentication of the spread spectrum code based on the spread spectrum code authentication information in the authentication message comprises: Obtaining a first chip correlation value corresponding to a target chip within a code shift keying code period in an authentication period of the composite code shift keying signal; Generate an encryption code chip based on the spread spectrum code authentication information in the authentication message, and obtain a corresponding second code chip correlation value; Correlating the first chip correlation value with the second chip correlation value to obtain a correlation result; In response to the correlation result being greater than a threshold value, the authentication is successful, otherwise the authentication fails.

8. The method according to claim 7, characterized in that The target code chip is a code chip at a target position of a target code shift keying code period within a target time period in the authentication period, the target code shift keying code period is one or more code shift keying code periods, and the target position is one or more continuous code chip positions.

9. The method according to claim 8, characterized in that Also includes: The position of the target code shift keying code period is obtained based on the spread spectrum code authentication information in the authentication message.

10. The method according to any one of claims 6 to 9, characterized in that Demodulating the composite code shift keying signal comprises: The high-speed telegram data and the authentication telegram data in the composite code shift keying signal are demodulated according to the code shift keying mode, and the low-speed telegram data in the composite code shift keying signal is demodulated according to the binary phase shift keying mode.

11. A satellite network device, characterized in that: include: one or more processors; as well as One or more memories coupled to the one or more processors and storing instructions thereon, which, when the instructions are executed individually or collectively by the one or more processors, cause the satellite network device to perform the method of any one of claims 1-5.

12. A terminal device, characterized in that: include: one or more processors; as well as One or more memories coupled to the one or more processors and storing instructions thereon, which, when the instructions are executed individually or collectively by the one or more processors, cause the terminal device to execute the method of any one of claims 6-10.

13. A chip, characterized in that: The method comprises a circuit system configured to perform the method of any one of claims 1-10.

14. A non-transitory computer-readable storage medium storing machine-executable instructions, characterized in that: When the machine executable instructions are executed by one or more processors of a machine, the machine is caused to perform the method of any one of claims 1-10.

15. A computer program product comprising machine executable instructions, characterized in that When the machine executable instructions are executed by one or more processors of a machine, the machine is caused to perform the method of any one of claims 1-10.

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