One: Demand background
Traditional urban road monitoring is mostly based on fiber-optic network transmission. However, before some events or large-scale events begin, temporary monitoring points need to be added. In this case, temporarily laying optical fiber and other signal lines will shorten the construction cycle time, cost, and use. short time. If you use traditional 4G network transmission, because the crowd density during the event is high, the coverage effect of the base station may be difficult to meet the HD transmission requirements. Therefore, the use of microwave wireless transmission technology can effectively meet the requirements for use.
Recently, our company received a request from a customer to hold a large-scale event locally. In order to improve safety and security, temporary monitoring points need to be added to the rooftops, street light poles and other places near the event site. However, there is currently no monitoring network signal line access in these places, so the signal cannot be transmitted to the public security management center by wire. However, due to time constraints, temporary laying of lines cannot be completed before the interaction begins. Therefore, the customer found that our company hopes to use a rapid network deployment method to integrate the entire temporary monitoring system networking components. According to the requirements of customers, we proposed the use of wireless bridging to achieve the project requirements.
2: Equipment Selection
1. Traditional bridge
Most of the wireless bridges we use are network communication in point-to-point or point-to-multipoint mode. These wireless modes can be used in traditional fixed monitoring. In addition, this type of network bridge is basically transmitted in a directional manner. For the temporary increase of monitoring and control points, rapid deployment, flexible mobility, and automatic linking are the basic requirements.
2.Wireless ad hoc network
Through the self-organizing network function of the non-center ad hoc network device, during the network operation, each wireless network node is peer-to-peer, and can automatically connect with other wireless network nodes nearby to establish a connection at the same time. Line, other network nodes will search for and link other network paths by themselves to realize signal return and realize network self-healing function. It is very suitable for occasions with temporary monitoring, which reduces the amount of installation and commissioning and the difficulty of construction, and shortens the construction time.
Three: Design link
The three additional monitoring points are located on the ring-shaped pedestrian bridge, street lights, and roadside rooftops. Among them, the roadside rooftops aggregate the signals of various temporary monitoring terminals into the command and dispatch network, and the central platform and the connected base stations communicate with each other. Realize the real-time monitoring of communication to each terminal.
Four: Application details
The wireless base stations of the monitoring terminals are located on the street light poles and pedestrian bridges at the T-junctions. The temporarily added monitoring points are connected to each wireless terminal, and the signals are merged with the top end of the building through the wireless ad hoc network, as shown below
Footbridge base station
Street light pole base station
Rooftop base station
After the network test, the speed between the two base stations on the top of the base station and the street light poles and the pedestrian bridge reached 60 Mbps, and the speed between the two base stations between the pedestrian bridge and the street light pole reached 40 Mbps. The network bandwidth is sufficient to support the transmission requirements of the surveillance camera signals.
Four: system advantages
Using the LA-850G single-frequency high-power fast ad hoc network function system to achieve rapid interconnection between wireless base stations, and quickly and easily deploy temporary monitoring points to achieve efficient monitoring construction and application.