Raytrans Link Network Optical Terminal in Tunnel Construction

During tunnel excavation, telephone, voice intercom, and voice broadcast stations need to be deployed along the route. Radio intercom distance is severely limited, requiring additional relay stations along the path.

The industrial-grade dual-optical-port integrated optical terminal NTD421 is used along the route, each station providing two telephone lines, with the central end connected to a telephone switch. The application is shown in Figure 1.

General video surveillance, stress detection, ventilation control, and lighting control along the route can also be integrated into the same communication system (though in practice, these communication systems often use a separate set of communication equipment, typically dual-optical-port media converters, serial port servers, and PoE power supply).

IDM POE-M08 += 3 units of gigabit media converters + 3 gigabit port 8 fast Ethernet port switches + 4-port serial port server + 150W 8-port PoE power supply. As shown in Figure 2.

The following issues exist in these solutions:

1. Using a standard telephone switch, when two users are on a call, other users with urgent business cannot perform barge-in, forced release, or other priority calls.

2. Using an independent telephone switch cannot connect audio intercom terminals, broadcast terminals, or wireless intercoms, hindering the integration of multiple communication methods.

3. Using a telephone switch cannot implement conference calls, telephone broadcasts, or other functions.

4. Separate communication systems for voice and video result in numerous communication devices, power interfaces, fiber interfaces, messy installation, and complex maintenance.

Raytrans provides high-performance, integrated central and remote solutions. The central end features an integrated audio/video dispatch switch IDM OMP2000-4E1-60 with dual gigabit optical ports, while the remote end uses IDM GTD442, which provides two physically isolated wire-speed gigabit Ethernet ports (typically one for video surveillance and the other for measurement data transmission, control data transmission, etc.). Four audio channels are used for telephone interfaces, intercom interfaces, broadcast interfaces, and wireless intercom forwarding interfaces. Additionally, there are 2 RS485 interfaces that can be aggregated to the central end's serial port server card and converted to Ethernet interfaces for connection to the data server.