Application of Communication Command Dispatch Switch in Highway and High-Speed Railway Construction Sites

Current Situation and Issues:

With the grand blueprint of the national "Belt and Road" initiative and the establishment of the "Asian Infrastructure Investment Bank," the construction scale of basic transportation infrastructure such as highways and high-speed railways will accelerate significantly.

These construction sites are generally temporary structures, mostly located in remote areas with poor communication conditions. There are many construction points along the route, involving numerous workers, requiring extensive coordination, and often operating in various hazardous environments. In tunnels and caves, two-way radios cannot function effectively, necessitating the use of telephones and wired intercom systems. Additionally, strategically deploying WIFI access points can enable indoor positioning.

In emergencies, departments such as firefighting, public security, healthcare, and electric power may also be involved, requiring each department to coordinate with others. Frequent switching of two-way radio channels is impractical, and some units' radios may not operate on the same frequency range or standard, such as the 350 MHz band, 800 MHz band, or air communication band. Leaders may also need to understand the command site situation via GSM mobile phones or landlines.

The best solution is to build a wired and wireless dispatch system for each construction area, integrating local radio communication, landline phones, GSM phones, and even broadcasting, displays, video cameras, and GPS location information into a single dispatch system.

Due to the remote locations of construction sites, operators have limited communication resources in these areas, and communication bandwidth is generally low. When establishing a dispatch system, it is advisable to build a dedicated communication system that comprehensively addresses telephony, two-way radio, networking, and video solutions. Raytrans' dispatch communication system integrates dispatch, communication access, communication transmission, and video transmission, incorporating both optical fiber and wireless transmission, lowering the user's operation and maintenance threshold and making system integration easier. For example, IDM G3CP and IDM M9000 are dispatch devices with SDH and other transmission interfaces.

Dispatch systems in different areas can interconnect, enabling both independent and collaborative operation.

Requirements:

On-site command personnel need to be equipped with multiple wireless trunking radios, especially those of different frequency bands and standards. These radios are linked together via a dispatch switch, enabling monitoring, command, and group merging through the dispatch console.

The same dispatch switch can configure a dispatch console for each department (i.e., the same frequency point). Given the complexity of the site, operators may not be familiar with computers, so a Danish-key dispatch console without a computer is preferable. Sites with communication vehicles can be equipped with touchscreen dispatch consoles and audio/video dispatch. The dispatch console allows users to hear voices from their own group and the collaboration process of other groups of interest, with flexible and convenient selection and settings.

The dispatch switch can also be equipped with GSM/CDMA phone cards or 4G communication cards to maintain external communication.

Voice recording equipment can be installed to record all on-site voice communications.

A comprehensive dispatch system can also bind video signals, enabling voice and data coordination. It can synchronize with geographic location information, displaying the location of dispatched objects in real time.

Application System:

The following diagram shows an example of an on-site dispatch system application.

(1) Function Introduction of IDM M9000 Communication Command Dispatch Switch:

In the diagram, the IDM M9000 can accommodate 12 access service cards.

If radio interface cards are inserted, each card can connect up to 4 radios (trunking).

If telephone cards are inserted, each card can support 8 telephone lines (FXO or FXS).

If GSM/CDMA phone cards are inserted, each card can connect 2 mobile phone SIM cards.

The WG300 processing card has an IP phone gateway function, enabling the interworking of analog voice services with IP (compliant with SIP standard VOIP protocol), allowing dispatch and data storage over IP.

The central processing card WG300 also has TDM-based telephone switching functionality. It can perform program-controlled telephone switching for voice services on the IDM M9000, with interchangeable user and trunk port quantities, totaling 120 channels.

The central processing card WG300 supports multi-party voice conferencing, allowing the allocation of conference rooms for trunking radios and IDM MCC keyboard dispatch consoles, enabling flexible multi-party calling.

The central processing card WG300 also has E1-based digital signaling extension functionality, supporting conversion of China No. 1, China No. 7, and PRI signaling.

(2) Function Introduction of IDM MCC Dispatch Console:

The IDM MCC is an IP keyboard dispatch console without a computer system. It can connect to the IDM M9000 via an Ethernet switch, offering flexible installation locations. It features a built-in 10W loudspeaker and can be deployed over any IP channel for ease of use.

The IDM MCC is equipped with 5 sets of radio corresponding keys (configurable).

Monitoring Function: When monitoring a selected radio, the corresponding indicator shows the monitoring status color. If the radio trunking channel has audio, the loudspeaker outputs sound, and the corresponding channel indicator flashes.

Speaking Function: If a channel is allowed to speak (configurable), the speaking indicator lights up. Pressing the group broadcast key broadcasts the microphone audio to all allowed trunking groups.

For enhanced dispatch functionality, a dispatch server and touchscreen dispatch console are required.

(3) IDM NTD421 is a chain network optical terminal that can directly connect to the IDM M9000 dispatch switch, providing network, telephone, and data access. It is suitable for use in tunnel construction.

For larger Ethernet bandwidth, the IDM GTD 442 chain network device can be used.

If traditional telephone services are not required, the IDM POE-M8 chain network gigabit media converter can be used. This device has POE power supply functionality, facilitating terminal access, such as POE-powered WIFI routers and POE-powered network cameras. The total power supply capacity of IDM POE-M8 is 150W. If POE power supply is not needed, the device cost can be significantly reduced.