DTMB single-frequency network transmitter anti-interference controller based on SIP frame check

Abstract

The invention discloses a DTMB single-frequency network transmitter anti-interference controller based on SIP frame inspection, and the controller comprises an SIP detection module which is used for obtaining an original TS code stream through a DVB-ASI collection card, detecting an SIP packet with the PID of 0 * 15 in a packet header through an FPGA, carrying out time synchronization detection through a 1PPS pulse signal, and immediately notifying a transmitter control module when the SIP packet is detected to be lost; the transmitter control module is used for controlling the DTMB exciter to switch to a multi-frequency network mode to work after receiving the notification of the SIP detection module, and notifying the alarm module to carry out sound-light alarm; and the alarm module is used for carrying out voice and red light alarm after receiving the command of the transmitter control module, and reminding that the original code stream SIP packet is abnormal and the current working mode is changed into the multi-frequency network mode. According to the DTMB single-frequency network transmitter anti-interference controller based on SIP frame inspection, through accurate detection and rapid response of the SIP detection module, the DTMB single-frequency network transmitter anti-interference controller can be rapidly switched to a multi-frequency network mode when an SIP packet is lost, and signal interruption caused by interference signals is effectively avoided.

Description

Technical Field

[0001] The present invention specifically relates to an anti-interference controller for a DTMB single-frequency network transmitter based on SIP frame inspection. Background Art

[0002] The technology of terrestrial digital television single-frequency network (SFN) is an advanced broadcast coverage method. By broadcasting the same program at the same frequency from different transmitting points, high-quality coverage of a specific area can be achieved. This technology has significant advantages such as improving spectrum utilization rate, enhancing coverage effect, and reducing transmitter power. However, the single-frequency network has extremely high requirements for the signal source. Its transmitter needs to use a satellite signal with a single-frequency network adapter equipped at the front end as the signal source and extract the time standard from GPS. The single-frequency network adapter carries key system parameters, such as timestamp flags, channel coding modulation, maximum delay, etc., by inserting SIP packets (second frame initialization packets) into the transmitted TS stream. The integrity and accuracy of SIP packets are crucial for the normal operation of the single-frequency network.

[0003] In practical applications, the field strength of the satellite downlink signal is weak, and the satellite receiving antenna is easily affected by external interference signals such as radar signals in the 3700MHz - 4200MHz band, 5G signals, and electromagnetic interference. Especially in areas with complex electromagnetic environments, such as the Beigao Peak Transmitter, the ASI signal output by the satellite receiver is abnormal, resulting in the loss of SIP packets in the bitstream. Once the SIP packets are lost, after the single-frequency network transmitter exciter reads the SIP packets incorrectly, the bitstream output is interrupted, causing phenomena such as a black screen at the receiving end, and the recovery time is relatively long. This not only affects the normal broadcast of radio and television programs but also brings great pressure to the security broadcast guarantee in the single-frequency network mode. Currently, the State Administration of Radio, Film and Television has extremely high requirements for the safe broadcast of DTMB (Digital Terrestrial Multimedia Broadcast) programs. Especially during key periods or for important programs during important guarantee periods, the outage time cannot exceed 3 seconds. Therefore, improving the anti-interference ability of the single-frequency network transmitter and ensuring the stable transmission of signals have become urgent problems to be solved. Summary of the Invention

[0004] The present invention provides an anti-interference controller for a DTMB single-frequency network transmitter based on SIP frame inspection to solve the above-mentioned technical problems, and specifically adopts the following technical solutions:

[0005] An anti-interference controller for a DTMB single-frequency network transmitter based on SIP frame inspection, comprising:

[0006] The SIP detection module is used to obtain the original TS stream through a DVB-ASI capture card, detect the SIP packet with PID 0x15 in the packet header through an FPGA, and simultaneously perform time synchronization detection using a 1PPS pulse signal. When a SIP packet loss is detected, it immediately notifies the transmitter control module;

[0007] The transmitter control module is used to, after receiving the notification from the SIP detection module, control the DTMB exciter to switch to the multi-frequency network mode for operation and notify the alarm module to give an audible and visual alarm; when no SIP packet loss information is received for 10 consecutive seconds, control the exciter to resume the single-frequency network operation mode and notify the alarm module of the fault recovery;

[0008] The alarm module is used to give a voice and red light alarm after receiving the command from the transmitter control module, reminding of the abnormality of the original stream SIP packet and the current working mode being changed to the multi-frequency network mode; when receiving a signal recovery instruction, reminding that the system has been restored to the single-frequency network mode.

[0009] Further, the SIP detection module further includes:

[0010] The signal preprocessing unit is used to filter the collected ASI signal, dynamically adjust the filtering parameters using an adaptive filter to suppress interference signals; at the same time, amplify and equalize the signal to improve the signal-to-noise ratio of the signal and restore the original characteristics of the signal.

[0011] Further, the SIP detection module further includes:

[0012] The interference source identification unit is used to analyze the collected signal using machine learning algorithms, identify and classify different types of interference sources, such as radar signals, 5G signals, and electromagnetic interference, etc.; take targeted anti-interference measures according to the type of interference source.

[0013] Further, the SIP detection module further includes:

[0014] The multi-level detection mechanism, in addition to performing second-level detection based on the 1PPS signal, also sets up a fast detection mechanism with a period of 10 milliseconds; within each second period, 100 fast detections are first performed. If 5 consecutive fast detections fail, a warning signal for SIP packet loss is triggered in advance.

[0015] Further, the SIP detection module further includes:

[0016] The SIP packet integrity verification unit is used to perform a more in-depth verification on the content of the SIP packet, check whether the timestamp flag in the SIP packet conforms to the expected time series law, and whether key system parameters such as channel coding and modulation parameters and maximum delay are consistent.

[0017] Furthermore, the transmitter control module further includes:

[0018] A smooth switching unit, which is used to adopt a smooth switching strategy when switching from the single-frequency network mode to the multi-frequency network mode and when recovering from the multi-frequency network mode to the single-frequency network mode, set a transition stage, and gradually adjust the power ratio of the two modes to avoid signal mutations caused by mode switching.

[0019] Furthermore, the transmitter control module further includes:

[0020] A switching condition refinement unit, which is used to consider other key parameters of the transmitter, such as transmit power, modulation error rate, etc., in addition to the conditions based on SIP packet loss and recovery when switching modes, to ensure the accuracy and reliability of the switching.

[0021] Furthermore, the transmitter control module further includes:

[0022] A cooperative control unit, which is used to perform cooperative control with the front-end single-frequency network adapter and the receiver, establish a communication mechanism, notify the front-end single-frequency network adapter to adjust its working state, and notify the receiver to adjust its receiving parameters in advance to better receive signals.

[0023] Furthermore, the alarm module further includes:

[0024] A detailed fault information display unit, which is used to display detailed information such as the specific time of SIP packet loss, the duration of the loss, the SIP packet timestamp information before and after the loss, the type of interference signal detected, etc. when alarming; set different levels of alarm information and adopt different acoustic and optical alarm methods.

[0025] Furthermore, the alarm module further includes:

[0026] A remote notification unit, which is used to send alarm information to maintenance personnel via text messages, emails, or mobile applications, etc. when alarming; set multiple notification objects and notification levels, and the notification content includes detailed information such as the time, reason, and recommended handling measures of the alarm.

[0027] For the DTMB single-frequency network transmitter anti-interference controller based on SIP frame inspection of the present application, the beneficial effects of the present invention are as follows:

[0028] The present invention provides a DTMB single-frequency network transmitter anti-interference controller based on SIP frame inspection. Through the precise detection and rapid response of the SIP detection module, it can quickly switch to the multi-frequency network mode when SIP packets are lost, effectively avoiding signal interruption caused by interference signals. At the same time, the addition of the signal preprocessing unit and the interference source identification unit further enhances the system's adaptability to complex electromagnetic environments and significantly improves the anti-interference performance.

[0029] The present invention provides an anti-interference controller for a DTMB single-frequency network transmitter based on SIP frame inspection, including a smooth switching unit and a switching condition refinement unit in the transmitter control module, which ensure a smooth transition of the signal during the mode switching process and avoid signal mutations and interruptions caused by switching. The setting of the collaborative control unit enables the front-end single-frequency network adapter and the receiving end to adjust their working states in a timely manner, further ensuring the stable transmission of the signal.

[0030] The present invention provides an anti-interference controller for a DTMB single-frequency network transmitter based on SIP frame inspection. The detailed fault information display unit and the remote notification unit of the alarm module can issue an audible and visual alarm in a timely manner when the SIP packet is lost, and send the detailed fault information to the maintenance personnel. This not only speeds up the fault diagnosis speed but also improves the system recovery efficiency and reduces the downtime.

[0031] The present invention provides an anti-interference controller for a DTMB single-frequency network transmitter based on SIP frame inspection. Through a multi-level detection mechanism and a SIP packet integrity verification unit, the SIP packet is detected more comprehensively and deeply, improving the accuracy and reliability of the detection. At the same time, the overall design of the system takes into account various possible interference factors and fault conditions, and through the synergistic effect of various technical means, significantly improves the reliability of the system. Brief Description of the Drawings

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0033] Figure 1 It is a schematic diagram of an anti-interference controller for a DTMB single-frequency network transmitter based on SIP frame inspection of the present invention. Detailed Embodiments

[0034] The following will describe in detail the embodiments of the present application. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present application and should not be construed as a limitation of the present application.

[0035] The anti-interference controller for a DTMB single-frequency network transmitter based on SIP frame inspection of the present application is used to improve the anti-interference ability of the single-frequency network transmitter in a complex electromagnetic environment and ensure the stable transmission of the signal. As Figure 1Shown is an anti-interference controller for a DTMB single-frequency network transmitter based on SIP frame inspection according to the present application, including: an SIP detection module, a transmitter control module, and an alarm module. Each module works in coordination to achieve precise detection of SIP packets, intelligent switching of the transmitter mode, and timely alarm for faults. This design enables the controller to quickly and accurately detect the loss of SIP packets in a complex electromagnetic environment, and take timely measures to ensure stable signal transmission, meeting the requirements of the radio and television public service system for signal transmission stability and reliability.

[0036] The main function of the SIP detection module is to perform SIP packet detection on the input ASI bitstream. Specifically, the SIP detection module obtains the original TS bitstream through a DVB-ASI capture card, and uses an FPGA to detect the SIP packets in the bitstream. The PID of the SIP packet is 0x15, and by detecting this PID, the SIP packet can be accurately identified. At the same time, a 1PPS pulse signal is used for time synchronization detection to ensure the accuracy and real-time performance of the detection. When the loss of an SIP packet is detected, the SIP detection module immediately notifies the transmitter control module. In this way, the SIP detection module can monitor the status of SIP packets in real time, and once the loss of an SIP packet is found, it immediately triggers subsequent anti-interference measures to ensure the rapid response of the system.

[0037] The transmitter control module is responsible for the communication and control of the DTMB transmitter exciter. After receiving the notification from the SIP detection module, the transmitter control module controls the DTMB exciter to switch to the multi-frequency network mode of operation, and notifies the alarm module to give an audible and visual alarm. When no SIP packet loss information is received for 10 consecutive seconds, it controls the exciter to resume the single-frequency network mode of operation and notifies the alarm module of the fault recovery. This control mechanism ensures that the transmitter can quickly switch to the multi-frequency network mode when an SIP packet is lost, reducing the signal interruption time, and can timely switch back to the single-frequency network mode after the signal is restored, ensuring the continuity and stability of signal transmission.

[0038] The alarm module is used to give a voice and red light alarm after receiving the command from the transmitter control module, reminding that the SIP packet of the original bitstream is abnormal and the current working mode has been changed to the multi-frequency network mode. When receiving a signal recovery instruction, it reminds that the system has been restored to the single-frequency network mode. The setting of the alarm module enables maintenance personnel to timely understand the operating status of the system, quickly respond to faults, reduce the outage time, and improve the reliability of the system.

[0039] In an embodiment of the present application, the SIP detection module further includes a signal preprocessing unit. The signal preprocessing unit is used to filter the collected ASI signal, dynamically adjust the filtering parameters using an adaptive filter to suppress interference signals. At the same time, the signal is amplified and equalized to improve the signal-to-noise ratio of the signal and restore the original characteristics of the signal. The addition of the signal preprocessing unit effectively improves the interference suppression ability of the SIP detection module, enhances the quality and stability of the signal, and provides a more reliable signal basis for subsequent SIP packet detection.

[0040] In an embodiment of the present application, the SIP detection module further includes an interference source identification unit. The interference source identification unit is used to analyze the collected signal using a machine learning algorithm, identify and classify different types of interference sources, such as radar signals, 5G signals, and electromagnetic interference, etc. Targeted anti-interference measures are taken according to the type of interference source. Through the interference source identification unit, the system can accurately identify the type of interference source and take corresponding anti-interference measures, improving the intelligence level and anti-interference ability of the system.

[0041] In an embodiment of the present application, the SIP detection module is provided with a multi-level detection mechanism. In addition to performing second-level detection based on the 1PPS signal, a multi-level fast detection mechanism with a period of 10 milliseconds is also set. Within each second cycle, 100 fast detections are first performed. If the fast detections fail continuously for 5 times, a warning signal for SIP packet loss is triggered in advance. The setting of the multi-level detection mechanism enables the system to detect the loss of SIP packets in a shorter time, issue a warning signal in advance, and gain more time for subsequent anti-interference measures, further improving the response speed and reliability of the system.

[0042] In an embodiment of the present application, the SIP detection module further includes a SIP packet integrity verification unit. The SIP packet integrity verification unit is used to perform a more in-depth verification of the content of the SIP packet, check whether the timestamp flag in the SIP packet conforms to the expected time series law, and whether key system parameters such as channel coding modulation parameters and maximum delay are consistent. The addition of the SIP packet integrity verification unit further improves the accuracy of SIP packet detection, ensuring that only complete and expected SIP packets can be recognized, and reducing the possibility of misjudgment.

[0043] In an embodiment of the present application, the transmitter control module further includes a smooth switching unit. The smooth switching unit is used to adopt a smooth switching strategy when switching from the single-frequency network mode to the multi-frequency network mode and when restoring from the multi-frequency network mode to the single-frequency network mode, set a transition stage, and gradually adjust the power ratio of the two modes to avoid signal mutations caused by mode switching. The setting of the smooth switching unit effectively reduces signal mutations during mode switching, improves the smoothness of signal transmission, and reduces the impact on the receiving end.

[0044] In an embodiment of the present application, the transmitter control module further includes a handover condition refinement unit. The handover condition refinement unit is used to consider other key parameters of the transmitter, such as transmit power, modulation error rate, etc., in addition to the conditions based on SIP packet loss and recovery, to ensure the accuracy and reliability of the handover when in the handover mode. The addition of the handover condition refinement unit makes the system more cautious when in the handover mode, considering more key parameters, improving the accuracy and reliability of the handover, and reducing signal interruption caused by incorrect handovers.

[0045] In an embodiment of the present application, the transmitter control module further includes a cooperative control unit. The cooperative control unit is used to perform cooperative control with the front-end single-frequency network adapter and the receiving end, establish a communication mechanism, notify the front-end single-frequency network adapter to adjust its working state, and notify the receiving end to adjust its receiving parameters in advance to better receive the signal. The setting of the cooperative control unit realizes the cooperative work of the transmitter control module with the front-end single-frequency network adapter and the receiving end, improving the overall performance of the system and the stability of signal transmission.

[0046] In an embodiment of the present application, the alarm module further includes a detailed fault information display unit. The detailed fault information display unit is used to display detailed information such as the specific time of SIP packet loss, the duration of the loss, the SIP packet timestamp information before and after the loss, and the type of interference signal detected during an alarm. Different levels of alarm information are set, and different acoustic and optical alarm methods are adopted. The addition of the detailed fault information display unit enables maintenance personnel to more clearly understand the specific situation of the fault, quickly locate the problem, and improve the fault handling efficiency.

[0047] In an embodiment of the present application, the alarm module further includes a remote notification unit. The remote notification unit is used to send alarm information to maintenance personnel via text messages, emails, or mobile applications during an alarm. Multiple notification objects and notification levels are set, and the notification content includes detailed information such as the time, reason, and recommended handling measures of the alarm. The setting of the remote notification unit enables maintenance personnel to receive alarm information in a timely manner even when not on site, quickly respond to the fault, and further improve the reliability and maintenance efficiency of the system.

[0048] Through the cooperative work of the above-mentioned various modules, the anti-interference controller of the DTMB single-frequency network transmitter based on SIP frame inspection of the present invention can effectively improve the anti-interference ability of the single-frequency network transmitter in a complex electromagnetic environment, ensure the stable transmission of signals, and meet the requirements of the radio and television public service system for signal transmission stability and reliability.

[0049] The basic principles, main features and advantages of the present invention have been shown and described above. Those skilled in the art should understand that the above embodiments do not limit the present invention in any form. Any technical solutions obtained by means of equivalent replacement or equivalent transformation shall fall within the protection scope of the present invention.

Claims

1. A DTMB single-frequency network transmitter anti-interference controller based on SIP frame inspection, characterized in that It includes: An SIP detection module, which is used to obtain the original TS stream through a DVB-ASI capture card, detect the SIP packet with PID 0x15 in the packet header through an FPGA, and simultaneously perform time synchronization detection using a 1PPS pulse signal. When an SIP packet loss is detected, it immediately notifies the transmitter control module; A transmitter control module, which is used to control the DTMB exciter to switch to the multi-frequency network mode of operation after receiving the notification from the SIP detection module, and notify the alarm module to give an audible and visual alarm; When no SIP packet loss information is received for 10 consecutive seconds, it controls the exciter to resume the single-frequency network mode of operation and notifies the alarm module of the fault recovery; An alarm module, which is used to give a voice and red light alarm after receiving the command from the transmitter control module, reminding that the SIP packet of the original stream is abnormal and the current working mode has been changed to the multi-frequency network mode; when receiving a signal recovery instruction, it reminds that the system has been restored to the single-frequency network mode.

2. The anti-interference controller of the DTMB single-frequency network transmitter based on SIP frame inspection according to claim 1, wherein The SIP detection module further includes: A signal preprocessing unit, which is used to filter the collected ASI signal, dynamically adjust the filtering parameters using an adaptive filter to suppress interference signals; at the same time, amplify and equalize the signal to improve the signal-to-noise ratio of the signal and restore the original characteristics of the signal.

3. The anti-interference controller for a DTMB single-frequency network transmitter based on SIP frame inspection according to claim 1, wherein The SIP detection module further includes: An interference source identification unit, which is used to analyze the collected signal using a machine learning algorithm, identify and classify different types of interference sources, such as radar signals, 5G signals, and electromagnetic interference; take targeted anti-interference measures according to the type of interference source.

4. The anti-interference controller of the DTMB single-frequency network transmitter based on SIP frame inspection according to claim 1, characterized in that, The SIP detection module further includes: A multi-level detection mechanism. In addition to performing second-level detection based on the 1PPS signal, it also sets up a fast detection mechanism with a period of 10 milliseconds; within each second period, 100 fast detections are first performed. If 5 consecutive fast detections fail, a warning signal for SIP packet loss is triggered in advance.

5. The anti-interference controller for a DTMB single-frequency network transmitter based on SIP frame inspection according to claim 1, characterized in that, The SIP detection module further includes: An SIP packet integrity verification unit, which is used to perform a more in-depth verification of the content of the SIP packet, check whether the timestamp flag in the SIP packet conforms to the expected time series law, and whether the channel coding and modulation parameters and the maximum delay are consistent.

6. The anti-interference controller for a DTMB single-frequency network transmitter based on SIP frame inspection according to claim 1, wherein The transmitter control module further includes: A smooth switching unit, which is used to adopt a smooth switching strategy when switching from the single-frequency network mode to the multi-frequency network mode and when restoring from the multi-frequency network mode to the single-frequency network mode, set up a transition stage, and gradually adjust the power ratio of the two modes to avoid signal mutations caused by mode switching.

7. The anti-interference controller of the DTMB single-frequency network transmitter based on SIP frame inspection according to claim 1, wherein The transmitter control module further includes: A switching condition refinement unit, which is used to consider other key parameters of the transmitter, such as the transmit power and modulation error rate, in addition to the conditions based on SIP packet loss and recovery when switching modes, to ensure the accuracy and reliability of the switching.

8. The anti-interference controller for a DTMB single-frequency network transmitter based on SIP frame inspection according to claim 1, characterized in that, The transmitter control module further includes: A cooperative control unit, which is used to perform cooperative control with the front-end single-frequency network adapter and the receiving end, establish a communication mechanism, notify the front-end single-frequency network adapter to adjust the working state, and notify the receiving end to adjust the receiving parameters in advance to better receive the signal.

9. The anti-interference controller of the DTMB single-frequency network transmitter based on SIP frame inspection according to claim 1, characterized in that The alarm module further includes: A detailed fault information display unit is used to display the specific time of SIP packet loss, the duration of loss, the SIP packet timestamp information before and after loss, and the detected interference signal type during an alarm; different levels of alarm information are set, and different acoustic and optical alarm methods are adopted.

10. The anti-interference controller of the DTMB single-frequency network transmitter based on SIP frame inspection according to claim 1, characterized in that, The alarm module further includes: A remote notification unit is used to send alarm information to maintenance personnel via text message, email, or mobile application during an alarm; multiple notification objects and notification levels are set, and the notification content includes the time, reason, and recommended handling measures of the alarm.

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