An integrated cable and fence detection system

Abstract

The application discloses an integrated cable and fence detection system, the integrated cable comprising: a signal acquisition cable bus and a vibration sensing module arranged on the signal acquisition cable bus, the signal acquisition cable bus comprising a control line and a signal line; the vibration sensing module comprising: a signal conversion chip, a MEMS acceleration sensor and a resistor; wherein the resistor is connected in series on the control line, the MEMS acceleration sensor is electrically connected to the signal conversion chip, and the signal conversion chip is further electrically connected to the control line and the signal line respectively. The fence detection system comprises: a system signal processor and the integrated cable electrically connected to the system signal processor, and the system signal processor collects the detection signal of the vibration sensing module through the signal acquisition cable bus. Thus, the application provides an integrated cable and fence detection system, which can accurately locate the vibration source and is stable, anti-noise and low-cost.

Description

Technical Field

[0001] This invention relates to the field of power security technology, specifically to an integrated cable and fence detection system. Background Technology

[0002] Vibration cables are a type of perimeter alarm detector, mainly used around fences around buildings and facilities. They enable the detector to climb or break through the fence to trigger an intrusion alarm.

[0003] Traditional vibration detection cables use pressure-sensitive cables or equal-capacitance cables as sensors to acquire electrical signals generated by the deformation of the cable due to fence vibration. Because the entire cable (over 100 meters) is a detection source (i.e., an infinite number of signal sources), these detectors are prone to background noise superposition, leading to false alarms. Therefore, they cannot accurately locate (or are completely unable to locate) the vibration source, necessitating the addition of more equipment to divide the field into more protection zones in complex applications.

[0004] In addition, the transmission of electrical signals can be affected by temperature changes (perimeter sensors are mainly used outdoors where temperature changes are large) or the binding method. Therefore, complex self-calibration is required; otherwise, distorted signals are easily generated. Summary of the Invention

[0005] To overcome the shortcomings of existing technologies, this invention proposes a fence detection system with integrated cables that can operate stably and locate vibration sources.

[0006] First, the present invention provides an integrated cable, comprising: a signal acquisition cable bus and one or more vibration sensing modules disposed on the signal acquisition cable bus, wherein,

[0007] The signal acquisition cable bus includes control lines and signal lines;

[0008] The vibration sensing module includes a signal conversion chip, a MEMS accelerometer, and a resistor; wherein the resistor is connected in series on the control line, the MEMS accelerometer is electrically connected to the signal conversion chip, and the signal conversion chip is also electrically connected to the control line and the signal line respectively.

[0009] Based on the above technical solution, the present invention can be further improved as follows.

[0010] Preferably, the MEMS accelerometer is a 3-axis MEMS accelerometer.

[0011] Preferably, the signal conversion chip is a vibration signal conversion microprocessor.

[0012] Preferably, multiple vibration sensing modules are arranged at fixed distances and equal intervals on the signal acquisition cable bus.

[0013] Based on this, the present invention provides a fence detection system, which includes: a system signal processor and the aforementioned integrated cable electrically connected to the system signal processor, wherein the system signal processor acquires the detection signal of the vibration sensing module through the signal acquisition cable bus.

[0014] Preferably, after initialization, each signal conversion chip outputs a high level to both the control line and the information line. The MEMS accelerometer converts the vibration signal into an electrical signal, which is then acquired and processed by the signal conversion chip. Based on the vibration amplitude and frequency signal or vibration intensity result, the signal conversion chip calculates an average vibration intensity value at set intervals. The signal conversion chip also detects the level of the control line in real time. When a high level is detected, it immediately outputs a low level and simultaneously outputs a pulse to the signal line. After the pulse is released, it immediately restores the high-level output of the control line and the signal line.

[0015] Preferably, the system signal processor obtains vibration intensity information by counting the number of pulses on the signal line; more preferably, the system signal processor defines the position with the highest number of vibration pulses as the source center, and calculates the proportion of the pulse count of 2-3 modules near the source center to the total number of pulses of 5-10 modules near the source center.

[0016] Preferably, the system signal processor detects the voltage value on the control line to identify different sources of the pulse.

[0017] Preferably, the fence detection system of the present invention further includes an alarm module electrically connected to the system signal processor.

[0018] Compared with the prior art, the present invention has the following technical features:

[0019] (1) Because a 3-axis accelerometer based on MEMS technology is used, the detector can adapt to various temperature changes (most MEMS chips on the market integrate temperature detection and automatic compensation functions), and achieve long-term stable measurement.

[0020] (2) Multiple modules on the bus independently detect vibration, and the system processor can distinguish the signal of each sensing module, eliminating the background noise superposition on the hundreds of meters of sensing cable in traditional vibration cables;

[0021] (3) Due to the realization of vibration source positioning, all systems (hundreds of meters in length) can be divided into multiple independent defense zones, which can significantly reduce the system construction cost. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the fence detection system of the present invention;

[0024] Figure 2 This is a flowchart illustrating the operation of the fence detection system of the present invention.

[0025] The following is a list of component names represented by each number in the attached diagram:

[0026] 1-System signal processor; 2-Control line; 3-Signal line; 4-Signal conversion chip;

[0027] 5-MEMS accelerometer; 6-Resistor. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Please refer to Figure 1 The diagram shown is a structural schematic of the fence detection system of the present invention. The fence detection system includes: a system signal processor 1, and an integrated cable of the present invention electrically connected to the system signal processor 1, wherein...

[0030] The integrated cable of the present invention includes: a signal acquisition cable bus and one or more vibration sensing modules disposed on the signal acquisition cable bus. In the fence detection system of the present invention, the system signal processor 1 acquires the detection signal of the vibration sensing module through the signal acquisition cable bus; specifically,

[0031] Please refer to Figure 1As shown, the signal acquisition cable bus includes a control line 2 and a signal line 3. The vibration sensing module includes a signal conversion chip 4, a MEMS accelerometer 5, and a resistor 6. The resistor 6 is connected in series on the control line 2, the MEMS accelerometer 5 is electrically connected to the signal conversion chip 4, and the signal conversion chip 4 is electrically connected to the control line 2 and the signal line 3.

[0032] Please refer to Figure 2 The diagram shown illustrates the workflow of the fence detection system of the present invention. The workflow of the fence detection system of the present invention includes the following steps:

[0033] S1: Initialization;

[0034] S2: Each signal conversion chip 4 outputs a high level to the control line 2 and the information line 3 respectively, that is, the control line 2 and the signal line are both in a high level state.

[0035] S3: During normal operation, the MEMS accelerometer 5 converts the vibration signal into an electrical signal (analog signal or digital signal), which is then acquired and processed by the signal conversion chip 4;

[0036] S4: The signal conversion chip 4 calculates an average vibration intensity value at regular intervals (e.g., 500ms) based on signals such as vibration amplitude and frequency or vibration intensity results;

[0037] S5: The signal conversion chip 4 also detects the level of the control line 2 in real time. When a high level is detected, it immediately outputs a low level and simultaneously outputs a pulse to the signal line 3.

[0038] After step S5 is completed, return to step S2 and immediately restore the high-level output of the control line 2 and the signal line 3.

[0039] Preferably, the system signal processor 1 obtains vibration intensity information by counting the number of pulses on the signal line 3, i.e., the signal line 3 is a counting line; also preferably, the system signal processor 1 detects the voltage value on the control line 2 to identify different sources of the pulses.

[0040] In this invention, both signal lines and control lines are connected via a bus connection, meaning all sensing modules are connected in parallel. The signal lines and control lines are connected to different I / O ports of the signal conversion chip, and each module is connected in series with a resistor on the control line.

[0041] In this invention, the MEMS accelerometer is preferably a 3-axis MEMS accelerometer (or "3-axis MEMS accelerometer chip", hereinafter referred to as the sensor chip), and the signal conversion chip is preferably a vibration signal conversion microprocessor (hereinafter referred to as the conversion chip). The conversion chip is used to acquire accelerometer signals (which can be analog or digital signals depending on the type of sensor chip), calculate vibration amplitude and frequency, and then normalize them to vibration intensity. More preferably, multiple vibration sensing modules are arranged at fixed distances and equal intervals on the signal acquisition cable bus.

[0042] In this invention, under normal circumstances, all conversion chips output a high level to both the control and signal lines, meaning both lines are in a high-level state. When the cable is subjected to external vibration, the sensing chip of the vibration sensing module near the vibration point receives the vibration intensity. The conversion chip first detects whether the control line is in a high-level state. If it is, meaning other modules are not using the signal line, the conversion chip of this module sends a low-level signal to the control line. Simultaneously, the conversion chip outputs a different number of low-level pulses to the signal line according to the magnitude of the vibration acceleration G, until all vibration pulses of the signal line of this module have been output. Then, the conversion chip restores the control line to a high level.

[0043] If a vibration sensing module detects a low-level control line while other modules are using the signal line, the conversion chip continuously monitors the control line level until it returns to a high level before entering transmission mode. This prevents multiple modules from sending vibration pulses simultaneously.

[0044] In this way, the system signal processor can distinguish the source of the pulse by measuring the voltage on the control line (because the control line is connected in series with a resistor, different voltages will be obtained at the system processor position when the low level output of different sensing modules is located), thus realizing the vibration localization; at the same time, the intensity of the vibration can be obtained by the number of pulses received on the signal line.

[0045] Furthermore, for intrusions at specific locations (single points) within the fence, the 1-3 modules near the intrusion point exhibit greater vibration intensity, sending a larger number of pulses to the processor; other modules farther from the intrusion point vibrate very little, sending fewer vibration pulses or even none. Therefore, the processor counts the pulses grouped by voltage to obtain vibration pulses in voltage dimension, and the vibration pulse count will be concentrated in the voltage group corresponding to the intrusion point.

[0046] In practical implementation, the system signal processor defines the location with the highest vibration pulse count as the source center, and calculates the proportion of pulses from 2-3 modules near the source center to the total pulse count of 5-10 modules near the source center. This is referred to as the source vibration proportion, which is typically greater than 50% for intrusions. However, in windy or rainy weather, the source vibrations caused by wind and rain are very dispersed, and each vibration module has an equal probability of vibration, so the source vibration proportion is typically less than 50%. During actual use and debugging, the source vibration proportion of intrusions will be simulated and tested to further distinguish between human intrusions and environmental interference, reducing false alarms.

[0047] In this invention, the overall process can be summarized as: sensing - processing (quantitative conversion) - transmission - analysis - alarm; specifically,

[0048] 1) Install a vibration sensing module every 3-5m on the cable;

[0049] 2) The conversion chip outputs a different number of low-level pulses to the signal line according to the magnitude of the vibration acceleration G value, with the G value ranging from 0 to 5G;

[0050] 3) The processor processes and interprets the cable vibration signal at a certain sampling period;

[0051] 4) The normal sampling period is set to (100ms-200ms);

[0052] 5) The sampling period needs to be greater than the total number of modules in the system's cabling configuration multiplied by the maximum number of signal pulses sent by a single chip; (this ensures that the cable has an idle state).

[0053] 6) If the conversion chip is damaged, it will continuously output a low-level signal. The processor will treat a low-level signal that lasts for more than 2 seconds as a sign of damage.

[0054] 7) Preferably, an alarm module electrically connected to the system signal processor can also be provided to trigger an alarm.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fence detection system, characterized in that, include: The system includes a signal processor, an integrated cable electrically connected to the system signal processor, a signal acquisition cable bus, and one or more vibration sensing modules disposed on the signal acquisition cable bus. The signal acquisition cable bus includes control lines and signal lines. Each vibration sensing module includes a signal conversion chip, a MEMS accelerometer, and a resistor. The resistor is connected in series on the control line, the MEMS accelerometer is electrically connected to the signal conversion chip, and the signal conversion chip is also electrically connected to the control line and the signal line. The system signal processor acquires the detection signal from the vibration sensing module through the signal acquisition cable bus, and uses the voltage on the control line to distinguish the source of the pulse, and obtains the intensity of the vibration by the number of pulses received on the signal line.

2. The fence detection system as described in claim 1, characterized in that, The MEMS accelerometer is a 3-axis MEMS accelerometer.

3. The fence detection system as described in claim 1, characterized in that, The signal conversion chip is a vibration signal conversion microprocessor.

4. The fence detection system as described in claim 1, characterized in that, Multiple vibration sensing modules are arranged at fixed distances and equal intervals on the signal acquisition cable bus.

5. The fence detection system as described in claim 1, characterized in that, After initialization, each signal conversion chip outputs a high level to the control line and the signal line respectively. The MEMS accelerometer converts the vibration signal into an electrical signal, which is collected and processed by the signal conversion chip. The signal conversion chip calculates an average vibration intensity value at set intervals based on the vibration amplitude and frequency signal or vibration intensity result. The signal conversion chip also detects the level of the control line in real time. When a high level is detected, it immediately outputs a low level and simultaneously outputs a pulse to the signal line. After the pulse is output, it immediately restores the high level output of the control line and the signal line.

6. The fence detection system as described in claim 5, characterized in that, The system signal processor obtains vibration intensity information by counting the number of pulses on the signal line.

7. The fence detection system as described in claim 5, characterized in that, The system signal processor detects the voltage value on the control line to identify different sources of pulses.

8. The fence detection system as described in claim 6, characterized in that, The system signal processor defines the location with the highest number of vibration pulses as the source center, and calculates the proportion of the pulse count of 2-3 modules near the source center to the total number of pulses of 5-10 modules near the source center.

9. The fence detection system as described in claim 1, characterized in that, It also includes an alarm module electrically connected to the system signal processor.

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