A distributed video monitoring system and method

Abstract

The present invention discloses a distributed video monitoring system and method. It relates to the field of video monitoring, wherein the distributed video monitoring system includes: a central node and multiple optical add / drop nodes, the central node includes a first number of central optical modules, the central optical modules are converged into an optical fiber through an optical splitter / combiner, the optical add / drop node includes an input port, an output port and a second number of add / drop optical modules, the input port is connected to the optical fiber, the output port is connected to the add / drop optical module, the add / drop optical module is connected to the video monitoring access node in sequence, and the wavelength of the add / drop optical module corresponds to the same wavelength of the central optical module. The system structure is simple, and the access of multiple video monitoring points can be realized with only one optical fiber chain topology, the wiring is simple, the maintenance cost is low, and the number of required optical modules is greatly saved, which reduces the system cost. In addition, the optical add / drop node realizes the convergence of multi-channel optical signals, and no expensive switches are required, so the system cost is low.

Description

Technical Field

[0001] The present invention relates to the field of video monitoring, and in particular to a distributed video monitoring system and method. Background Art

[0002] In order to meet the needs of comprehensive transformation of power grid automation and intelligence, it is very necessary to establish an image video monitoring system to understand the real situation of remote unattended sites more comprehensively, intuitively, timely and accurately. In order to monitor the site of each substation / station, the image monitoring system needs to be able to monitor and monitor the relevant data, environmental parameters and images of each substation / station, and transmit them to the local dispatching / monitoring center, so as to understand and grasp the situation of each substation / station in real time and directly, and respond to the situation in time. For unmanned stations, this approach not only reduces the operation frequency of inspection personnel, but also strengthens the safety, security and fire alarm monitoring of substations / stations, and improves the safety of power grid operation. The implementation of the power monitoring system provides a strong technical guarantee for realizing unmanned substations / stations and promoting the management of power grids to gradually develop in the direction of automation and intelligence.

[0003] In the prior art, one method is to use a point-to-point transmission method between the monitoring center and the video monitoring point of the remote unmanned computer room to directly transmit the video data of the video monitoring point to the monitoring center, or to deploy a convergence switch near the remote unmanned computer room to converge multiple video monitoring points in one or several computer rooms into one optical fiber and uniformly transmit them to the monitoring center. However, both methods require a large number of optical modules and optical fiber connections, and the cost is high. Therefore, it is necessary to propose a monitoring system that realizes distributed video monitoring without introducing a large number of optical modules and optical fiber connections. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent. To this end, the object of the present invention is to provide a monitoring system for realizing distributed video monitoring without introducing a large number of optical modules connected to optical fibers.

[0005] The technical solution adopted by the present invention is:

[0006] In a first aspect, the present invention provides a distributed video surveillance system, comprising: a central node and a plurality of optical add / drop nodes;

[0007] The central node includes a first number of central optical modules, and the central optical modules are converged into the optical fiber through an optical splitter / combiner;

[0008] The optical add / drop node comprises an input port, an output port, and a second number of add / drop optical modules, the input port is connected to the optical fiber, the output port is connected to the add / drop optical module, and the add / drop optical module is connected to the video monitoring access node in sequence;

[0009] The wavelengths of the up-down wave optical modules are the same as the wavelength of the central optical module.

[0010] Furthermore, the optical wave add / drop node is connected to the optical fiber in a chain topology manner.

[0011] Furthermore, the wavelengths of the central optical modules are all different.

[0012] Furthermore, the second number is less than or equal to the first number.

[0013] Furthermore, the carrier frequencies of the optical add / drop nodes are all different.

[0014] Furthermore, the central optical module and the upper and lower wave optical modules have the same structure.

[0015] In a second aspect, the present invention further provides a distributed video monitoring method, which is applied to a distributed video monitoring system as described in any one of the first aspects, comprising:

[0016] Collecting video data of multiple video monitoring access nodes and sending it to the optical fiber through the up / down wave optical module;

[0017] The video data is sent to the central optical module through the optical fiber via the optical splitter / combiner.

[0018] The beneficial effects of the present invention are:

[0019] The distributed video monitoring system of the present invention comprises: a central node and a plurality of optical up / down wave nodes, the central node comprises a first number of central optical modules, the central optical modules are converged into an optical fiber through an optical splitter / combiner, the optical up / down wave nodes comprise an input port, an output port and a second number of up / down wave optical modules, the input port is connected to the optical fiber, the output port is connected to the up / down wave optical modules, the up / down wave optical modules are sequentially connected to the video monitoring access node, and the wavelength of the up / down wave optical modules corresponds to the same wavelength of the central optical module. The system structure is simple, and the access of multiple video monitoring points can be realized with only one optical fiber chain topology, the wiring is simple, the maintenance cost is low, and the number of required optical modules is greatly saved, thereby reducing the system cost. In addition, the optical up / down wave nodes realize the convergence of multiple optical signals, and no expensive convergence switch is required, so the system cost is low. It can be widely used in distributed video monitoring scenarios in power systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1It is a schematic diagram of a point-to-point transmission method in the prior art;

[0021] Figure 2 It is a schematic diagram of the transmission method using a convergence switch in the prior art;

[0022] Figure 3 It is a structural diagram of a specific embodiment of the distributed video monitoring system of the present invention;

[0023] Figure 4 It is a schematic diagram of the principle of a specific embodiment of the distributed video monitoring system in the present invention. DETAILED DESCRIPTION

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0026] Embodiment 1:

[0027] The specific requirements for the power video surveillance system are as follows: On the one hand, with the vigorous development of the power grid, local dispatching / monitoring centers often need to simultaneously monitor dozens or even hundreds of video monitoring points distributed in multiple locations around them; on the other hand, due to the characteristics of video surveillance, such as large bandwidth requirements and low latency, it is generally necessary to use Ethernet optical modules (such as 2.5GE optical modules) based on optical fiber transmission. Generally speaking, optical modules realize photoelectric conversion, and the sending end converts electrical signals into optical signals. After transmission through optical fiber, the receiving end converts the optical signals into electrical signals.

[0028] like Figure 1 As shown, it is a schematic diagram of the point-to-point transmission method in the prior art. It can be seen from the figure that under this transmission mode, the video data of the video monitoring points are directly transmitted to the monitoring center in a point-to-point one-to-one form. This method is more suitable for a smaller area with fewer video monitoring points. If the area is large and there are many video monitoring points, a large number of expensive optical modules are required, and a large number of long-distance optical fiber connections are used to connect the optical modules of the video monitoring points to the monitoring center, which is very expensive and difficult to deploy / maintain.

[0029] like Figure 2As shown, it is a schematic diagram of the transmission method using an aggregation switch in the prior art. In this method, an aggregation switch node is deployed near a remote unmanned computer room, and the video data of multiple video monitoring points in one or several computer rooms are aggregated into one optical fiber through optical modules, and uniformly transmitted to the monitoring center. This method simplifies the complexity of optical fiber connection and reduces the difficulty of deployment. However, this method still requires a large number of optical modules and requires additional aggregation switches, and the cost is still very high.

[0030] like Figure 3 As shown, it is a schematic diagram of the structure of a distributed video surveillance system provided in this embodiment. In order to solve the problems of limited access nodes, high wiring costs and high optical module costs in large-scale distributed video surveillance scenarios, a distributed video surveillance system based on combining frequency division multiplexing and wavelength division multiplexing technology is provided, including: a central node and multiple optical add / drop nodes. Correspondingly, corresponding optical add / drop nodes can be set according to the number of remote unmanned computer rooms to transmit video signals.

[0031] The central node includes a first number of central optical modules (eg, M central optical modules), which are converged into an optical fiber through an optical splitter / combiner, and are connected to multiple optical add / drop nodes in a chain topology.

[0032] The optical add / drop node is a passive node. Each optical add / drop node includes an input port, an output port, and a second number of add / drop optical modules. The input port is connected to the optical fiber, the output port is connected to the add / drop optical module, and the add / drop optical module is connected to the video monitoring access node in sequence.

[0033] In this embodiment, the second number is less than or equal to the first number. In an application scenario, the second number is equal to the first number. For example, both are M, and the central node includes M wavelengths of λ1 to λ M The central optical modules have different wavelengths and are connected to the corresponding add / drop wave optical modules through optical fibers, thereby being connected to the video monitoring access nodes in sequence. It can be seen that the first passive optical add / drop wave node is connected to the first to the Mth video monitoring access nodes in sequence, and the second passive optical add / drop wave node is connected to the M+1th to the 2Mth video monitoring access nodes in sequence, and so on. N passive optical add / drop wave nodes can be connected to N*M video monitoring access nodes in total.

[0034] like Figure 4As shown, it is a schematic diagram of the principle of a distributed video surveillance system of the present embodiment, in which two different carrier frequencies are represented by solid lines and dotted lines for illustration. In the present embodiment, the uplink video data modulation scheme of the video monitoring access node in the remote unattended machine room is as follows: for the x-th passive optical add / drop node, the second number of video monitoring access nodes connected to it modulate the uplink video data on a subcarrier with a frequency of Fx and transmit it through the corresponding optical wavelength. The carrier frequency of each optical add / drop node is different, which is used to distinguish different video sources.

[0035] First, the wavelengths corresponding to the add / drop optical modules of the first to the Mth video monitoring access nodes connected to the first passive optical add / drop node are λ1 to λ M For each video monitoring access node, the uplink video data is modulated on a subcarrier with a frequency of F1 using wavelengths of λ1 to λ M The optical transmitter transmits the video data; the M+1th to 2Mth video monitoring access nodes connected to the second passive wave adding and dropping node, each video monitoring access node, modulates the uplink video data on a subcarrier with a frequency of F2, using wavelengths of λ1~λ M The optical transmitter transmits the video data, and so on, each uplink video data is sent to the central node at different carrier frequencies and different wavelengths.

[0036] Then, the passive optical drop node will transmit the wavelengths λ1~λ M The video data signal is gathered on an optical fiber. For example, if there are N passive optical add / drop nodes, each passive optical add / drop node corresponds to M channels of video data, then the wavelengths λ1 to λ M , N*M channels of video data with subcarrier frequencies of F1~FN are gathered on one optical fiber and uniformly transmitted to the central node, thereby realizing distributed video monitoring of N*M video monitoring access nodes.

[0037] In this embodiment, the central optical module and the upper and lower wave optical modules have the same structure. The optional optical modules include: FTCS-DXX24-XXX produced by Chengdu Beiyi Fiber Technology Co., Ltd., HXSX-2L541C produced by Huaxun Optoelectronics, 2.5GCWDM SFP produced by Yifeiyang, etc.

[0038] The passive optical add / drop devices used in the passive optical add / drop nodes include: OADM add / drop multiplexers produced by Anjiekang, CWDM OADM upload / download multi-channel optical add / drop multiplexers produced by Shenzhen Feiyu, and optical wave add / drop multiplexer OADM modules produced by Shenzhen Langxunda Optoelectronics.

[0039] Optical splitters and combiners include: TR-CWDM1800 produced by Beijing Tuorui, multi-channel CWDM produced by Shenzhen Feiyu, 4-channel CWDM rack-mounted coarse wavelength division multiplexer produced by Xianyitong, etc.

[0040] The remote video monitoring point of this embodiment adopts a low-cost optical module, and realizes real-time transmission of multiple video signals in one optical fiber through low-cost passive optical add / drop nodes. The system structure is simple, and only one optical fiber chain topology is needed to realize the access of multiple video monitoring points, with simple wiring and low maintenance cost.

[0041] At the same time, as in the above application scenario, only (N+1)*M optical modules (M central optical modules and one for each N*M video access point) are needed to achieve access to N*M video monitoring points. Compared with the point-to-point transmission solution in the prior art (which requires 2*N*M optical modules), the number of required optical modules is greatly saved, thereby reducing the system cost.

[0042] In addition, this embodiment uses low-cost passive optical add / drop nodes to achieve the aggregation of multiple optical signals without the need for expensive aggregation switches, thus reducing system costs.

[0043] Embodiment 2:

[0044] This embodiment provides a distributed video monitoring method, which is applied to a distributed video monitoring system as described in any one of the first embodiments, and includes the following steps:

[0045] S1: Collect video data from multiple video monitoring access nodes and send them to the optical fiber through corresponding uplink and downlink optical modules;

[0046] S2: The video data is sent to the central optical module through the optical fiber through the optical splitter / combiner for video monitoring.

[0047] The distributed video monitoring system of the present invention comprises: a central node and a plurality of optical add / drop wave nodes, the central node comprises a first number of central optical modules, the central optical modules are converged into an optical fiber through an optical splitter / combiner, the optical add / drop wave nodes comprise an input port, an output port and a second number of add / drop wave optical modules, the input port is connected to the optical fiber, the output port is connected to the add / drop wave optical modules, the add / drop wave optical modules are connected to the video monitoring access nodes in sequence, and the wavelengths of the add / drop wave optical modules correspond to the same wavelengths of the central optical modules, and the system can be widely used in distributed video monitoring scenarios in power systems.

[0048] The above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. A distributed video surveillance system, characterized in that: include: A central node and multiple optical up / down wave nodes; The central node includes a first number of central optical modules, which are converged into an optical fiber through an optical splitter / combiner, and are connected to a plurality of optical wave add / drop nodes in a chain topology; the wavelengths of the central optical modules are all different, and are respectively connected to the wave add / drop optical modules through optical fibers; the optical wave add / drop nodes are passive nodes; The optical add / drop node comprises an input port, an output port and a second number of add / drop optical modules, the input port is connected to the optical fiber, the output port is connected to the add / drop optical module, and the add / drop optical module is connected to the video monitoring access node in sequence, so that the passive optical add / drop node transmits wavelengths λ1 to λ2 transmitted from the M video monitoring access nodes. M The video data signal is converged on an optical fiber; the carrier frequencies of the optical uplink and downlink nodes are different, so that each uplink video data is sent to the central node at different carrier frequencies and different wavelengths; the second number is less than or equal to the first number; The wavelength of the up-down wave optical module is the same as the wavelength of the central light module, and the central light module and the up-down wave optical module have the same structure.

2. A distributed video monitoring method, characterized in that: A distributed video surveillance system as claimed in claim 1, comprising: Collecting video data of multiple video monitoring access nodes and sending it to the optical fiber through the up / down wave optical module; The video data is sent to the central optical module through the optical fiber via the optical splitter / combiner.

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