Regional navigation communication method and system based on multi-user frequency hopping

Abstract

The invention discloses a regional navigation communication method and system based on multi-user frequency hopping. The system comprises air users divided into a plurality of sub-networks; and a plurality of ground base stations. According to the system, time-frequency domain resources are divided into a plurality of non-interfering network layers according to different frequency hopping patterns, and different members are divided in each sub-network by using a code division multiple access technology, so that hybrid multiple access is realized, while the signal measurement precision is guaranteed, certain concealment is realized, and the measurement accuracy is improved. And a regional navigation signal waveform system supporting anti-interference and low interception is formed.

Description

Technical Field

[0001] The present invention relates to the technical field of regional radio navigation systems, and in particular to a regional navigation communication method and system based on multi-user frequency hopping. Background Art

[0002] Current navigation systems rely heavily on satellite navigation systems. However, due to the hardware limitations of the positioning satellites themselves, the satellite signal transmission power is very low. Coupled with the spatial loss of long-distance channel transmission, the signal power reaching the receiver is only around -130dBm. At the same time, in various complex backgrounds, the complex and harsh natural environment, extremely fierce offensive and defensive confrontations, and highly coupled battlefield situations all pose great challenges to the research of high-dynamic and high-precision response positioning technology. In addition, in remote scenarios and over wide areas, the demand for navigation and positioning service accuracy and availability is also increasing.

[0003] Faced with the complex situation, research on high-reliability regional navigation technology in complex scenarios is imminent. It is necessary to explore and research a navigation system that is independent of satellites, has high reliability and is multi-user oriented, and use it as an effective supplement and backup for the satellite navigation system.

[0004] Compared with satellite navigation systems, land-based radio navigation systems offer unique advantages in terms of regional coverage, anti-interference capabilities, transmission frequency, and power. By designing the signal system and time slot structure of land-based regional navigation systems and employing frequency hopping, time hopping, and spread spectrum technologies, these systems achieve navigation and positioning capabilities while also providing strong resistance to interception and interference. This has significant practical significance for the development of land-based navigation and positioning technology. Summary of the Invention

[0005] The present disclosure provides a low-interception area navigation communication method based on multi-user frequency hopping, which is used for information transmission and positioning and ranging between multiple aerial users and a reference station. By dividing time-frequency domain channel resources, multi-user area navigation is realized in complex scenarios, and has the characteristics of low interception, anti-interference and high reliability.

[0006] The present disclosure provides a method for regional navigation communication based on multi-user frequency hopping, comprising the following steps:

[0007] S1, divide the air users into several sub-networks and allocate the time and frequency domain resources of the regional navigation communication channel to each sub-network;

[0008] S2, determining the transmission frame format of the regional navigation network downlink and uplink information based on the divided time-frequency domain resources;

[0009] S3: Navigation starts. The base station constantly monitors the downlink signal of the user in the air and waits to receive the downlink signal from the user.

[0010] S4, the air user transmits a downlink signal at the beginning of each time slot;

[0011] S5, the base station receives the downlink signal and sends an uplink signal to the air user;

[0012] S6, the airborne user receives uplink signals from multiple reference stations to achieve its own navigation and positioning.

[0013] Furthermore, the step S1 specifically includes:

[0014] S11: All airborne users are divided into several sub-networks, each using the same set of frequency hopping patterns. At the same time, downlink signals from airborne users in different sub-networks use different frequencies. When the base station receives downlink signals from different sub-networks, it uses frequency division multiplexing to distinguish them.

[0015] S12, divide each communication cycle into different time slots according to the number of air users in each sub-network, and each air user occupies one time slot; in the same sub-network, different air users use different time slots to broadcast downlink signals; when the base station receives the inquiry signal of the same sub-network, it uses time division multiple access to distinguish them.

[0016] Furthermore, the step S5 specifically includes:

[0017] S51, for each ground reference station, receiving downlink signals from different subnets in one time slot;

[0018] S52, replying uplink signals to different subnets in sequence according to the order of the subnets receiving the signals; the waiting time for replying the uplink signals is the delay of the uplink signals.

[0019] Furthermore, the step S6 specifically includes:

[0020] S61, multiple reference stations transmit uplink signals to air users in the same time slot. Each reference station has a specific codeword and is distinguished using code division multiple access.

[0021] S62, based on the uplink signals from multiple reference stations, the airborne user performs its own navigation and positioning.

[0022] A regional navigation communication system based on multi-user frequency hopping using the above method mainly comprises: air users divided into several sub-networks, and several ground reference stations; wherein:

[0023] Each sub-network uses the same frequency hopping pattern. At the same time, downlink signals from air users in different sub-networks use different frequencies. When the base station receives downlink signals from different sub-networks, it uses frequency division multiplexing to distinguish them.

[0024] Each communication cycle is divided into different time slots based on the number of air users in each sub-network, with each air user occupying one time slot. Different air users in the same sub-network use different time slots to broadcast downlink signals. When the base station receives interrogation signals from the same sub-network, it uses time division multiple access to distinguish them.

[0025] Each ground reference station receives downlink signals from different subnets in a time slot and replies uplink signals to different subnets in the order of the subnets in which the signals were received.

[0026] Each reference station has a specific codeword. When multiple reference stations transmit uplink signals to air users in the same time slot, they are distinguished by code division multiple access.

[0027] Airborne users perform their own navigation and positioning based on the uplink signals from multiple reference stations.

[0028] Compared with the existing technology, the beneficial effects of the present disclosure are: ① Aiming at the characteristics of regional radio navigation systems in satellite-denied environments, the present disclosure adopts a sub-network division method, comprehensively utilizes time, frequency and coding resources, modulates high-precision ranging and communication information waveforms, and realizes high-precision ranging and low-latency communication in multi-user networks;

[0029] ② According to user configuration requirements, the time division, frequency division and code division hybrid multiple access technology with time hopping and frequency hopping sequence spread spectrum is adopted to design the time frame and time slot structure of the hybrid multiple access signal;

[0030] ③ According to different frequency hopping patterns, the time-frequency domain resources are divided into multiple non-interfering network layers. Code division multiple access technology is used to divide different members in each sub-network to achieve hybrid multiple access;

[0031] ④ While ensuring the accuracy of signal measurement, it has a certain degree of concealment, forming a regional navigation signal waveform system that supports anti-interference and low interception. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and other objects, features and advantages of the present disclosure will become more apparent through a more detailed description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present disclosure.

[0033] Figure 1 A flowchart is generally executed according to an exemplary embodiment of the present disclosure;

[0034] Figure 2 FIG. 4 is a diagram showing time-frequency domain resource allocation according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0035] The preferred embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although preferred embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to make the present disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0036] The present disclosure provides a regional navigation communication method and system based on multi-user frequency hopping, which enables user equipment to safely transmit information and perform positioning and ranging between multiple aerial users and a reference station in a complex environment.

[0037] According to the exemplary embodiment of the present disclosure, the overall execution process is as follows: Figure 1 As shown, the following steps are included:

[0038] Step 1: Allocate time-frequency domain resources for regional navigation communication channels;

[0039] Step 2: Determine the downlink and uplink information transmission frame formats of the regional navigation network based on the divided time-frequency domain resources;

[0040] Step 3: Navigation starts. The airborne user transmits a downlink signal at the beginning of each time slot.

[0041] Step 4: The base station constantly monitors the downlink signal of the airborne user and waits to receive the downlink signal of the user;

[0042] Step 5: Receive the downlink signal and send the uplink signal to the air user after a certain delay;

[0043] Step 6: The airborne user receives uplink signals from multiple reference stations to meet its own navigation and positioning needs.

[0044] Specifically, the time-frequency domain resource division diagram in this embodiment is as follows: Figure 2 As shown, in step 1, the specific steps of allocating time-frequency domain resources of the regional navigation communication channel are:

[0045] (1) All airborne users are divided into several sub-networks, each of which uses the same set of frequency hopping patterns. At the same time, the downlink signals of airborne users in different sub-networks use different frequencies. The base station uses frequency division multiplexing to distinguish the downlink signals of different sub-networks.

[0046] (2) According to the number of air users in each sub-network, each communication cycle is divided into different time slots, and each air user occupies one time slot; in the same sub-network, different air users use different time slots to broadcast downlink signals; the base station uses time division multiple access to distinguish the inquiry signals received from the same sub-network.

[0047] In step 5, the specific steps of receiving the downlink signal and sending the uplink signal to the air user after a certain delay are as follows:

[0048] (1) Each ground reference station receives downlink signals from different subnets within a time slot;

[0049] (2) Reply uplink signals to different subnets in the order of the subnets that received the signals. The time it takes to reply to the uplink signals is the delay of the uplink signals.

[0050] In step 6, the specific steps for the airborne user to receive uplink signals from multiple reference stations and realize its own navigation and positioning needs are as follows:

[0051] (1) Multiple reference stations transmit uplink signals to air users in the same time slot. Each reference station has a specific codeword and is distinguished using code division multiple access.

[0052] (2) Based on the uplink signals from multiple base stations, airborne users can realize their own navigation and positioning needs.

[0053] The above technical solutions are only exemplary embodiments of the present invention. For those skilled in the art, it is easy to make various types of improvements or modifications based on the application methods and principles disclosed in the present invention, and are not limited to the methods described in the above specific embodiments of the present invention. Therefore, the methods described above are only preferred and do not have a restrictive meaning.

Claims

1. A method for regional navigation communication based on multi-user frequency hopping, for information transmission and positioning and ranging between multiple airborne users and a reference station, comprising the following steps: S1, divide the air users into several sub-networks and allocate the time and frequency domain resources of the regional navigation communication channel to each sub-network; S2, determining the transmission frame format of the regional navigation network downlink and uplink information based on the divided time-frequency domain resources; S3: Navigation starts. The base station constantly monitors the downlink signal of the user in the air and waits to receive the downlink signal from the user. S4, the air user transmits a downlink signal at the beginning of each time slot; S5, the base station receives the downlink signal and sends an uplink signal to the air user; S6, the airborne user receives uplink signals from multiple reference stations to achieve its own navigation and positioning.

2. The method according to claim 1, characterized in that The step S1 specifically includes: S11: All airborne users are divided into several sub-networks, each using the same set of frequency hopping patterns. At the same time, downlink signals from airborne users in different sub-networks use different frequencies. When the base station receives downlink signals from different sub-networks, it uses frequency division multiplexing to distinguish them. S12, divide each communication cycle into different time slots according to the number of air users in each sub-network, and each air user occupies one time slot; in the same sub-network, different air users use different time slots to broadcast downlink signals; when the base station receives the inquiry signal of the same sub-network, it uses time division multiple access to distinguish them.

3. The method according to claim 1, characterized in that The step S5 specifically includes: S51, for each ground reference station, receiving downlink signals from different subnets in one time slot; S52, replying uplink signals to different subnets in sequence according to the order of the subnets receiving the signals; the waiting time for replying the uplink signals is the delay of the uplink signals.

4. The method according to claim 1, wherein The step S6 specifically includes: S61, multiple reference stations transmit uplink signals to air users in the same time slot. Each reference station has a specific codeword and is distinguished using code division multiple access. S62, based on the uplink signals from multiple reference stations, the airborne user performs its own navigation and positioning.

5. A regional navigation communication system based on multi-user frequency hopping using the method according to any one of claims 1 to 4, characterized in that: include: Divided into several sub-networks of air users and several ground reference stations; among them: Each sub-network uses the same frequency hopping pattern. At the same time, downlink signals from air users in different sub-networks use different frequencies. When the base station receives downlink signals from different sub-networks, it uses frequency division multiplexing to distinguish them. Each communication cycle is divided into different time slots based on the number of air users in each sub-network, with each air user occupying one time slot. Different air users in the same sub-network use different time slots to broadcast downlink signals. When the base station receives interrogation signals from the same sub-network, it uses time division multiple access to distinguish them. Each ground reference station receives downlink signals from different subnets in a time slot and replies uplink signals to different subnets in the order of the subnets in which the signals were received. Each reference station has a specific codeword. When multiple reference stations transmit uplink signals to air users in the same time slot, they are distinguished by code division multiple access. Airborne users perform their own navigation and positioning based on the uplink signals from multiple reference stations.

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