Time division multiple access satellite communication method based on user isolated frequency hopping sequence

Abstract

The application relates to a time division multiple access satellite communication method based on user isolated frequency hopping sequences, which comprises the following steps: dividing a TDMA frame into M time slots, each time slot being allocated a unique user; a service access user negotiating with a ground management center to determine frequency hopping control parameters used in the service, and generating service frequencies of each beam based on the frequency hopping control parameters; adding the service frequencies of each beam to an adjustment factor to obtain adjusted service frequencies, and forming a service time slot frequency hopping sequence by the adjusted service frequencies of N beams. M time slots correspond to M frequency hopping sequences, and the M frequency hopping sequences are completely independent, the frequency hopping sequences have the characteristics of better privacy and anti-interception, the anti-interception probability of the frequency hopping signals is improved under the condition that the anti-interference ability of the frequency hopping communication system remains unchanged, and therefore the satellite communication safety is greatly enhanced.

Description

Technical Field

[0001] This application relates to the field of satellite communications, and more specifically, to a time division multiple access satellite communication method based on user isolation frequency hopping sequences. Background Technology

[0002] Frequency-hopping communication technology is widely used in satellite anti-jamming communication due to its excellent anti-interference capabilities. In a frequency-hopping system, the transmitter retrieves the frequency control code from the frequency-hopping frequency table to control the frequency synthesizer to output a local oscillator signal with frequency hopping. This local oscillator signal is then used to convert the modulation signal, thereby generating the frequency-hopping signal. Under the condition of complete system time synchronization, the receiver generates a frequency-hopping sequence locally with the same pattern as the transmitter, thus achieving synchronous reception of the frequency-hopping signal.

[0003] In existing time division multiple access frequency hopping communication systems, in order to meet the communication needs of multi-user networking in the time domain, multiple users are usually assigned to use the same frequency hopping codebook in the time domain for frequency hopping. However, this method has poor privacy among users, and attackers can crack the entire network communication by intercepting a single terminal. Therefore, it cannot meet the needs of communication systems under high security conditions. Improving the privacy and security of time division multiple access frequency hopping communication systems has become the most urgent issue. Summary of the Invention

[0004] To overcome at least one deficiency in the prior art, this application provides a time division multiple access satellite communication method based on user isolation frequency hopping sequence.

[0005] In one embodiment, a time-division multiple access satellite communication method based on user-isolated frequency hopping sequences includes: The TDMA frame is divided into M time slots, and each time slot is assigned a unique user. During the synchronization time slot, all users use the same frequency hopping control parameters for a period of time. K_Syn Based on frequency hopping control parameters K_Syn Generate the synchronization frequency for each beam, and the synchronization frequencies of N beams form a synchronization time slot frequency hopping sequence; During the access time slot, all users use the same frequency hopping control parameters for a period of time. K_Access, Based on frequency hopping control parameters K_Access The access frequency for each beam is generated, and the access frequencies of N beams form an access time slot frequency hopping sequence. During the service time slot, the service access user negotiates with the ground management center to determine the frequency hopping control parameters to be used for this service. K_u Based on frequency hopping control parameters K_u Generate the service frequency for each beam; add the service frequency of each beam to the adjustment factor to obtain the adjusted service frequency, and the adjusted service frequencies of N beams form a service time slot frequency hopping sequence.

[0006] In one embodiment, the total available frequency bandwidth of the frequency hopping satellite communication system is The frequency range is , This is the lower limit of frequency. This is the upper limit of the frequency. The signal bandwidth of each beam is And requires , The available frequency bandwidth of each beam in the beam is .

[0007] In one embodiment, the synchronization frequency, access frequency, and service frequency of each beam are all within the frequency range. Inside, This is the lower limit of frequency. This represents the upper limit of the frequency.

[0008] In one embodiment, when the adjusted service frequency is greater than , To set the frequency upper limit, adjust the service frequency to , For the first The service frequency of each beam For the first indivual time The adjustment factor below, This is the lower limit of frequency. This represents the upper limit of the frequency.

[0009] Compared with the prior art, this application has the following beneficial effects: In this application, a time division multiple access (TDMA) satellite communication system is divided into M time slots, with each time slot assigned to a unique user. The user utilizes frequency hopping control parameters negotiated with the ground management and control center. K_u A dedicated frequency hopping sequence is generated for each time slot. M time slots correspond to M frequency hopping sequences, and these sequences are completely independent, achieving user-isolated frequency hopping sequences. These sequences offer good privacy and anti-eavesdropping features. While maintaining the anti-interference capability of the frequency hopping communication system, the probability of eavesdropping on the frequency hopping signal is increased, thereby greatly enhancing satellite communication security and improving the system's anti-decryption capability by 10%. log10 (M) dB. Furthermore, during each communication, the user must negotiate frequency hopping control parameters with the ground management and control center within the allocated time slot. K_u This allows for one parameter per use, further enhancing system security. Attached Figure Description

[0010] This application can be better understood by referring to the description given below in conjunction with the accompanying drawings, which, together with the detailed description below, are incorporated in and form part of this specification. In the drawings: Figure 1 This illustrates a two-level security enhancement matrix for time-division multiple access satellite communications with user-isolated frequency hopping sequences; Figure 2 The time division multiple access satellite communication process based on user isolation frequency hopping sequence is shown. Detailed Implementation

[0011] Exemplary embodiments of the present application will be described below with reference to the accompanying drawings. For clarity and brevity, not all features of the actual embodiments are described in the specification. However, it should be understood that many embodiment-specific decisions can be made in the development of any such actual embodiment to achieve the developer’s specific objectives, and these decisions may vary as the embodiments differ.

[0012] It should also be noted that, in order to avoid obscuring this application with unnecessary details, only the device structure closely related to the solution of this application is shown in the accompanying drawings, while other details that are not closely related to this application are omitted.

[0013] It should be understood that this application is not limited to the described embodiments by virtue of the following description with reference to the accompanying drawings. In this document, embodiments may be combined with each other, features may be substituted or borrowed between different embodiments, and one or more features may be omitted in one embodiment, where feasible.

[0014] This application provides a time-division multiple access satellite communication method based on user-isolated frequency hopping sequences. First, the user terminal completes time-frequency synchronization and access operations on the synchronization time slot and access control time slot. Then, it uses independent frequency hopping control parameters on the allocated service time slot. K Frequency hopping sequences are generated to complete communication services. Throughout the entire frequency hopping communication system, the service phase employs a one-time protocol control parameter approach to ensure system security and reliability.

[0015] Figure 1 The time-division-slot two-level security enhancement matrix for time-division multiple access satellite communications with user-isolated frequency hopping sequences is shown. Figure 2 The time division multiple access satellite communication process based on user isolation frequency hopping sequence is shown.

[0016] After completing satellite-to-ground time and frequency synchronization and access using common control parameters, the user applies to the ground management center for the frequency hopping control parameters required for this communication time slot. K_u It is a 128-bit binary sequence.

[0017] Assume the total available frequency bandwidth of the frequency hopping satellite communication system is The frequency range is N beams, each with a signal bandwidth of And requires To ensure the system's maximum anti-interference capability, the available frequency bandwidth of each of the N beams is [missing information]. .

[0018] There are many methods for generating frequency hopping sequences, which are existing technologies. This application does not constrain any specific generation method. At any time, according to the frequency hopping control parameters K Generate frequency hopping sequences of N beams :

[0019] in, This is the lower limit of frequency. This represents the upper limit of the frequency.

[0020] No. The frequency of each beam As time changes (i.e.) And changes, and the frequency difference between any two beams in the N beams is greater than At the same time As the frequency changes, the output frequency also changes. Traditional frequency-hopping communication systems use the same frequency for a period of time. This application generates multiple frequency sequences for use by different beams. Provide exclusive users with private frequency sequences.

[0021] This application provides a time-division multiple access satellite communication method based on user isolation frequency hopping sequences, including: The TDMA frame is divided into M time slots, and each time slot is assigned a unique user. During the synchronization time slot, all users use the same frequency hopping control parameters for a period of time. K_Syn Based on frequency hopping control parameters K_Syn The synchronization frequency of each beam is generated, and the synchronization frequencies of N beams form a synchronization time slot frequency hopping sequence.

[0022] Synchronization time slots are used in frequency-hopping satellite communication systems to ensure that all users are synchronized with the satellite. Synchronous frequency hopping sequence generating N beams at any time :

[0023] in, For the first Synchronization frequency of each beam For the first One Tod moment.

[0024] During the access time slot, all users use the same frequency hopping control parameters for a period of time. K_Access, Based on frequency hopping control parameters K_Access The access frequency for each beam is generated, and the access frequencies of N beams form an access time slot frequency hopping sequence.

[0025] Access time slots are used in frequency-hopping satellite communication systems to ensure that all users can access the system. Frequency hopping sequence for N beams of access time slot generated at any time :

[0026] in, For the first The access frequency of each beam.

[0027] During the service time slot, the service access user negotiates with the ground management center to determine the frequency hopping control parameters to be used for this service. K_u Based on frequency hopping control parameters K_u Generate the service frequency for each beam; add the service frequency of each beam to the adjustment factor to obtain the adjusted service frequency, and the adjusted service frequencies of N beams form a service time slot frequency hopping sequence.

[0028] exist Generate service time slot frequency hopping sequence at all times : ，

[0029] in, For the first The service frequency of each beam , for Adjustment factor at any given time.

[0030] Here, during user communication, an adjustment factor is added to further increase the randomness of the frequency and enhance privacy.

[0031] Furthermore, when the adjusted service frequency Greater than , To set the frequency upper limit, adjust the service frequency to , For the first The service frequency of each beam For the first indivual time The adjustment factor below, This is the lower limit of frequency. This represents the upper limit of the frequency.

[0032] The Time Division Multiple Access (TDMA) satellite communication method based on user-isolated frequency hopping sequences in this application divides the TDMA frame into M time slots in a TDMA satellite communication system, assigning a unique user to each time slot. The user utilizes frequency hopping control parameters negotiated with the ground management and control center. K_u A dedicated frequency hopping sequence is generated for each time slot. M time slots correspond to M frequency hopping sequences, which are completely independent, achieving user-isolated frequency hopping sequences. These sequences offer good privacy and anti-eavesdropping features. While maintaining the anti-interference capability of the frequency hopping communication system, the probability of eavesdropping on the frequency hopping signal is increased, thereby greatly enhancing satellite communication security and improving the system's anti-decryption capability by 10%. log10 (M) dB.

[0033] The above descriptions are merely various embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A time-division multiple access satellite communication method based on user isolation frequency hopping sequences, characterized in that, include: The TDMA frame is divided into M time slots, and each time slot is assigned a unique user. During the synchronization time slot, all users use the same frequency hopping control parameters for a period of time. K_Syn Based on the frequency hopping control parameters K_Syn Generate the synchronization frequency for each beam, and the synchronization frequencies of N beams form a synchronization time slot frequency hopping sequence; During the access time slot, all users use the same frequency hopping control parameters for a period of time. K_Access, Based on the frequency hopping control parameters K_Access The access frequency for each beam is generated, and the access frequencies of N beams form an access time slot frequency hopping sequence. During the service time slot, the service access user negotiates with the ground management center to determine the frequency hopping control parameters to be used for this service. K_ u Based on the frequency hopping control parameters K_u Generate the service frequency for each beam; add the service frequency of each beam to the adjustment factor to obtain the adjusted service frequency, and the adjusted service frequencies of N beams form a service time slot frequency hopping sequence.

2. The method as described in claim 1, characterized in that, The total available frequency bandwidth of the frequency hopping satellite communication system is The frequency range is , This is the lower limit of frequency. This is the upper limit of the frequency. The signal bandwidth of each beam is And requires , The available frequency bandwidth of each beam in the beam is .

3. The method as described in claim 1, characterized in that, The synchronization frequency, access frequency, and service frequency of each beam are all within the frequency range. Inside, This is the lower limit of frequency. This represents the upper limit of the frequency.

4. The method as described in claim 1, characterized in that, When the adjusted service frequency is greater than , To set the frequency upper limit, adjust the service frequency to , For the first The service frequency of each beam For the first indivual time The adjustment factor below, This is the lower limit of frequency. This represents the upper limit of the frequency.

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