IDM M9000B Communication Command and Dispatch System

The IDM M9000B communication command and dispatch system is a TDM communication command and dispatch system developed by Beijing Ruiguang Jiyuan Digital Technology Co., Ltd. Centered on TDM time-slot switching, it can connect radio sets of different frequencies, formats, and types, trunking intercom, fixed-line telephones, magneto telephones, and satellite terminals to the same voice platform, achieving interconnection between heterogeneous wireless communication systems and wired networks. It is a converged communication command and dispatch system designed for emergency scenarios. A single IDM M9000B communication command and dispatch system supports up to 48 radio sets or 120 telephone terminals. Its integrated design eliminates the cascading of multiple gateways. It can rapidly form vehicle-mounted, fixed, portable, and mobile emergency intercommunication platforms for natural disasters, emergencies, counter-terrorism and stability maintenance, and training and exercises, providing stable and reliable audio and video dispatching and voice switching capabilities for on-site command and dispatch.

The development background of the IDM M9000B communication command and dispatch system stems from common shortcomings of existing dispatch equipment: wireless trunking dispatch and wired telephone dispatch are independent of each other; IP-based dispatching exchanges rely on cascading multiple gateways such as GOIP and ROIP, lacking integrated equipment; some dispatching exchanges simply stack multiple technologies, resulting in bulky equipment, complex management, small capacity, and long software startup times, and when connected to field military-grade telephones, they struggle to support access modes such as 2100Hz in-band signaling and DCP signaling. Emergency command relies heavily on group conferences. Under an IP architecture, the more conference members there are, the greater the processor load and the worse the voice quality. These are exactly the scenarios where a TDM time-slot switching architecture excels. As a professional command and dispatch system manufacturer, Raytrans addresses the above pain points by integrating command and dispatch, product showcase, and audio and video dispatching requirements into an integrated design. The dispatch console is simple and intuitive to operate, and can be flexibly deployed in combination with military emergency communications vehicle solutions and government private network optical fiber communication solutions.

Key Specifications at a Glance: 48 radio channels per unit · 120 telephone terminals · TDM time-slot switching, never busy · 32 conference calls · 12 hot-swappable user card slots · 11V~15V DC power supply

What kind of equipment is the IDM M9000B communication command and dispatch system?

The IDM M9000B communication command and dispatch system is an integrated dispatch host that consolidates switching, interfaces, and dispatch control in a single chassis. The host is equipped with a main control and switching card and 12 user card slots. The user card slots support mixed installation of VHF radio interface cards, FXS subscriber telephone cards, FXO central office telephone cards, Hot hotline phone cards, and MAG magneto telephone cards. All types of interface cards are hot-swappable. System status and user status are displayed by multi-color indicator LEDs, and system settings and function operations are assisted by an LCD screen.

Figure 1: IDM M9000B communication command and dispatch system host appearance — front panel user card slots and status indicator LEDs

The audio and video dispatching and command and dispatch control of the IDM M9000B communication command and dispatch system are based on TDM time-slot switching. The voice transmission and access section provides VoIP channels, while the deterministic switching remains in the dispatch core, and remote access can be flexibly enabled via wireless IP networks. A single host simultaneously provides multiple interfaces such as radio, telephone, magneto, satellite, and IP. Multi-format communication resources do not need to be distributed across multiple single-format gateway devices, and it can serve as the core equipment of a converged communication command and dispatch system.

What on-site problems does the integrated design solve?

Conclusion first: the three design features of the IDM M9000B communication command and dispatch system correspond to three types of on-site problems — slow field deployment, busy voice channels, and difficulty in obtaining power in the field. The correspondence between features and problems is shown in the table below.

The specific meaning of the integrated design is: dispatching switching, user card slots, and communication interfaces are delivered in the same chassis. For capacity expansion, simply insert the corresponding interface card into a free card slot, without purchasing a separate gateway for each type of terminal and cascading them one by one. For field operations, the complete unit is carried and can be powered on for dispatching once connected to a battery or vehicle power. The two features of TDM time-slot switching and portable power supply are elaborated separately below.

Why is the TDM communication command and dispatch system suitable for emergency command and high-security scenarios?

The TDM communication command and dispatch system is suitable for emergency command and high-security scenarios because of reserved bandwidth and deterministic switching. The command and dispatch control of the IDM M9000B communication command and dispatch system is based on TDM time-slot switching. Each call occupies a fixed 64K time slot in the switching matrix, so voice is never queued or blocked, with strong anti-interference capability and low voice latency. Traditional voice interface cards come in many types, switching response is fast, hardware voice conference rooms have large capacity, and all system modules start quickly, making it suitable for command occasions requiring rapid deployment.

IP dispatching in important fields usually requires the IP transmission network to provide guarantees such as port traffic limiting and VLAN partitioning, and basically depends on an IP private network; transmitting voice over an office network without IP transmission planning still poses security hazards. IP softswitch is susceptible to IP broadcast storms or other burst IP traffic, whereas the IDM M9000B communication command and dispatch system keeps the determinism of time-slot switching in the dispatch core and uses VoIP only as an access channel, balancing reliability and deployment flexibility. It remains the preferred product in application fields with high security requirements.

Knowledge Block: Differences Between TDM Dispatching and IP Softswitch

The differences between TDM dispatching and IP softswitch are mainly reflected in the switching mechanism and network dependency. The table below compares the IDM M9000B communication command and dispatch system (TDM time-slot switching) with common IP softswitch dispatch systems, item by item according to the dimensions of concern for dispatch services. The applicable conditions are private networks and emergency command scenarios.

Comparison shows that the advantages of TDM time-slot switching are concentrated in deterministic latency and resistance to burst traffic, while the advantage of IP softswitch lies in the universality of terminal access. The IDM M9000B communication command and dispatch system combines the two: dispatch control runs over TDM time-slot switching, while the access side retains VoIP channels, balancing the security requirements of private networks with access flexibility.

What Terminals and Trunk Interfaces Does the IDM M9000B Support?

The IDM M9000B communication command and dispatch system can be fitted with a WG300 card, providing 120 channels of 64K PCM voice (FXO, FXS, E&M voice, MAG, etc.), as well as radio set interfaces and VHF radio interfaces that meet multi-unit control standards, and providing a dispatch console Ethernet interface and 2 E1 interfaces for No.1, SS7, and PRI signaling access; the E1 interfaces can also be used to connect PCM expansion subscriber interface channels. Trunk and subscriber interfaces can be flexibly selected according to on-site network conditions.

Telephones and wired intercom terminals can be connected directly to FXS subscriber interfaces, and outside lines can also access dispatching resources on the IDM M9000B communication command and dispatch system through FXO interfaces, enabling outside lines to listen in on VHF radio interfaces. FXS subscriber interfaces connect ordinary telephones, PTT intercom terminals, and the like, and can also be transmitted over PCM access to more distant operating sites, extending dispatch coverage.

Figure 2: IDM M9000B direct connection terminal diagram — direct access mode for telephones and PTT terminals

What Communication Media and Networks Does the IDM M9000B Support?

As a mature audio and video dispatching and command and dispatch platform, the IDM M9000B communication command and dispatch system can aggregate multiple communication media — fixed-line telephone networks, cellular mobile communication networks, Internet (IP) networks, wireless local area networks, trunking mobile communication systems, and satellite communication systems — onto the same dispatching platform, achieving collaborative dispatch voice intercommunication between public and private networks, wired and wireless, and across regions and departments. The communication media diagram is shown below. The system provides unified voice access for different transmission media, so dispatchers do not need to distinguish whether a remote user is on an optical fiber, field wire, wireless link, or IP channel.

Figure 3: IDM M9000B communication media diagram — wired, wireless, IP, and satellite media access

On the IP side, the IDM M9000B communication command and dispatch system connects IP phones and other access terminals through the WAN port's electrical interface (RJ45) or optical interface (FC), and supports the transmission of radio signals (RoIP) and voice signals (VoIP) over IP networks. The combination of TDM time slots for dispatch control and IP channels for the access segment enables the system to rapidly enable remote voice channels over wireless IP networks, without waiting for IP private network planning to be completed.

Figure 4: Networking diagram of the IDM M9000B connected to IP network access terminals

How Many Radio and Telephone Channels Can the IDM M9000B Communication Command and Dispatch System Handle?

The overall capacity of the IDM M9000B communication command and dispatch system centers on the main control and switching card and user card slots: the main control and switching card can provide conference calls, supporting 32 simultaneous conference calls and 64 simultaneous DTMF detections, and provides 2 groups of E1 interfaces on the card, configurable as China SS7 signaling or PRI signaling, or as 60 subscriber interfaces. The unit provides 12 user card slots, each of which can be fitted with a VHF interface card, FXS subscriber telephone card, FXO central office telephone card, Hot hotline phone card, or MAG magneto telephone card; when a VHF radio interface card is inserted, each card provides 4 channels, and when FXS, FXO, or MAG cards are inserted, each card provides 10 channels. The main capacity and configuration parameters are shown in the table below.

What Operating Modes Do Radio Sets and Wireless Intercom Have?

The IDM M9000B communication command and dispatch system provides 4 basic operating modes for intercommunication between VHF radio sets and telephone terminals, and in practice the PA mode can be combined with the other modes. In multi-party conferencing mode, each VHF radio corresponds to a conference number, and listening telephones dial in to the conference room for free intercom; in ordinary telephone intercom mode, a telephone dials the radio set access number to listen, and presses the flash key or hook switch to obtain a talk right of 20 seconds (20 seconds by default, configurable); in PTT terminal intercom mode, the terminal normally listens and presses the PTT key to speak, with the speaking time determined by the terminal; in PA mode, the VHF radio sound is broadcast one-way to all telephones that have joined listening.

Access control of wireless channels supports 3 modes: audio interfaces with PTT function preferentially use PTT control mode when interfacing with radio sets and trunking interfaces; audio terminals without PTT function (such as conference microphones) use DSP volume control mode, controlling radio receive/transmit by dynamically monitoring the sound level; telephones and mobile phones can also send commands to the dispatching exchange via the dual-tone multi-frequency (DTMF) keyboard to control radio receive/transmit, and each wireless interface can select one control mode.

How Does the IDM M9000B Network with Raytrans Transmission and Access Equipment and Dispatch Consoles?

Through E1, PCM and optical transmission links, the IDM M9000B communication command and dispatch system can cascade with Raytrans' own transmission and access equipment, extending dispatch voice channels to remote stations. The E1 interface can serve as No.1, SS7 or PRI signaling trunk, or connect PCM extended subscriber interface channels, so that dispatching resources extend along the transmission network to remote telephones, intercom terminals and radio sets, forming a command network with centralized scheduling and distributed access.

Figure 5: Networking diagram of the IDM M9000B connected to Raytrans transmission and access equipment

In terms of coordination with dispatch consoles, the IDM M9000B communication command and dispatch system supports fiber-optic networking with various Raytrans TDM dispatch consoles, and all command operator seats share the same dispatching resource; the dispatch core is still implemented by TDM time-slot switching, so voice latency between multiple TDM dispatch consoles is low and conference quality is consistent, making it suitable for collaborative command across command posts in different locations.

Figure 6: Diagram of fiber-optic networking between the IDM M9000B and various Raytrans TDM dispatch consoles

The IDM M9000B communication command and dispatch system can also work with the IDM MCC IP keyboard dispatch console to perform intercom dispatch; the IP keyboard dispatch console accesses the system through an Ethernet switch, allowing flexible installation locations. The dispatcher initiates an intercom on the IP keyboard dispatch console, and the system bridges the radio voice channel and the dispatch console voice channel, enabling one-touch radio intercom command.

Figure 7: Diagram 1 of the intercom process between the IDM M9000B and the IDM MCC IP keyboard dispatch console

Figure 8: Diagram 2 of the intercom process between the IDM M9000B and the IDM MCC IP keyboard dispatch console

In addition, the IDM M9000B communication command and dispatch system supports networking with various Raytrans IP dispatch consoles; dispatch consoles can be deployed over any IP channel, and both wired and radio set users can be incorporated into a unified dispatch interface, so additional operator seats are not limited by the equipment room location.

Figure 9: Diagram of networking between the IDM M9000B and various Raytrans IP dispatch consoles

How Do Multi-Unit Interconnection, Cascading Capacity Expansion and Optical Fiber Ring Networks Expand Capacity?

IDM M9000 series converged communication command and dispatch system supports multi-unit networking. Each device can be connected to other devices of the same series through twisted pair, E1, or IP routing. A single unit can connect up to 48 radio sets or 120 telephone terminals, and up to 60 channels of intercom terminals (including local-end and remote-end audio terminals). The number of same-class devices that can be connected to the IDM M9000C remote end depends on the number of trunk ports; with two E1 ports configured, it does not exceed 110 channels of loop-start trunk FXO ports. Multi-unit networking is suitable for multi-site, multi-detachment echeloned command systems. Each node device operates independently while being interconnected, providing a flexible networking foundation for audio and video dispatching.

Figure 10: IDM M9000 Series Communication Command and Dispatch System Multi-Unit Networking Application Topology Diagram

When radio capacity needs to be expanded, the IDM M9000 series can perform multi-unit cascading capacity expansion through E1: the radio interface card provides 4-channel interfaces, and each E1 interface can expand 30 channels of radio interfaces. A device used as an expansion cascade only serves as a PCM expansion interface, no longer providing dispatching switching functions, and has no operating panel, resulting in lower capacity expansion cost and maintenance complexity.

Figure 11: IDM M9000 Series Multi-Unit E1 Cascading Capacity Expansion Networking Diagram

In post deployment scenarios, the IDM M9000 series can implement audio and video surveillance command through an optical fiber ring network, accessing 120 channels of wired and wireless systems. The advantage of the ring network is that a fiber break at some point in the middle does not affect normal communication; a call is connected as soon as the handset is lifted at the remote end, and images are displayed synchronously. PA announcements and transfers can be made to each post, and telephones and trunking intercoms can monitor simultaneously, achieving a combination of mobile posts and fixed posts. The system supports up to 8 optical fiber rings, with every two rings sharing 30 telephone channels; the ring network plug-in card is the IDM MPconv card, and the remote end connects to IDM NTD421 devices.

Figure 12: IDM M9000 Series Optical Fiber Ring Network Audio and Video Post Deployment System Networking Diagram

What command and dispatch functions does the system provide?

The core functions of the IDM M9000B converged communication command and dispatch system cover the complete chain from interface access to command operations. The specific role of each function is shown in the table below.

What are the features of the TDM-based hardware design?

What dispatch operations can the dispatch console software perform?

The dispatch console software of the IDM M9000B converged communication command and dispatch system organizes operation functions according to command services, covering call control, PA announcements, trunking intercom, and emergency management. The specific dispatch operation capabilities are shown in the table below.

The multimedia interface and equipment form factor examples of the dispatch console are shown in the following figures. The dispatcher completes daily command and dispatch operations such as click-to-call, status viewing, and conference organization through the graphical operator seat.

Figure 13: Example 1 of the IDM M9000B companion dispatch console introduction interface

Figure 14: Example 2 of the IDM M9000B companion dispatch console introduction interface

Figure 15: Example 3 of the IDM M9000B companion dispatch console introduction interface

Figure 16: Example 4 of the IDM M9000B companion dispatch console introduction interface

Figure 17: Example 5 of the IDM M9000B companion dispatch console introduction interface

The IDM M9000B converged communication command and dispatch system can be equipped with a variety of Raytrans dispatch console models, and job roles such as the command center, duty console, and mobile command can select models as required: the IDM-MCC21 multimedia dispatch console is suitable for multimedia audio and video command operator seats, the IDM-MCC12 multimedia dispatch console is suitable for routine audio and video dispatching, the IDM-MCC10 portable dispatch console is convenient for vehicle-mounted and field carrying, the IDM-MCC telephone-line dispatch console accesses the system over a telephone line, the IDM-MCC Danish-key IP audio dispatch console provides IP audio Danish-key operation, and the IDM-MCC7 multi-function dispatch console integrates multiple dispatching operations.

Figure 18: IDM-MCC21 multimedia dispatch console — multimedia audio and video command operator seat

Figure 19: IDM-MCC12 multimedia dispatch console — routine audio and video dispatching seat

Figure 20: IDM-MCC10 portable dispatch console — vehicle-mounted and field mobile command

Figure 21: IDM-MCC telephone-line dispatch console — telephone-line access keyboard dispatch console

Figure 22: IDM-MCC Danish-key IP audio dispatch console — IP audio operation seat

Figure 23: IDM-MCC7 multi-function dispatch console — multi-function integrated dispatching seat

What are the roles of a SIP magneto gateway and a SIP telephone access gateway?

Between the IP network and magneto telephones, the IDM M9000B converged communication command and dispatch system requires a SIP magneto telephone access gateway (IDM-MAGgate) to complete interface conversion and meet the SIP protocol standard. The IDM-MAGgate telephone gateway provides 2 magneto telephone interfaces and supports line fault detection; the Ethernet electrical interface is a 10/100BASE-T full-duplex, half-duplex adaptive RJ45 connector, compliant with IEEE 802.3, 802.1P, and 802.1Q; the Ethernet optical interface is 10/100BASE-FX with an FC connector. Through this gateway, remote field magneto telephones can access the IDM M9000B dispatching platform over the IP network, achieving long-distance extension of magneto telephones.

Figure 24: IDM-MAGgate single-channel IP magneto gateway device appearance

Figure 25: IDM-MAGgate dual-channel IP magneto gateway device front appearance

Figure 26: IDM-MAGgate dual-channel IP magneto gateway device rear interfaces

Between the IP network and analog telephones, the IDM M9000B converged communication command and dispatch system uses the IDM IAD02 integrated access gateway to complete conversion, which also meets the SIP protocol standard and can interconnect with standard SIP softswitch systems, providing VoIP and FoIP solutions for carriers, enterprises, and residential community users. The IDM IAD02 provides 1 WAN port and 4 LAN ports; the WAN port supports an electrical port (RJ45) and an optical port (FC), and in the optical interface form it can intercommunicate with a 100M media converter; it provides 2 analog telephone interfaces (FXS) and 1 escape interface (FXO), where one telephone can dial "0" to reach the PSTN (or set the PSTN connection method through the network management system), and when power fails this telephone automatically accesses the PSTN, ensuring that basic telephone service remains available after a power failure.

Figure 27: IDM IAD02 integrated access gateway device appearance — SIP telephone access gateway

Figure 28: IDM IAD02 integrated access gateway device rear interfaces

Figure 29: IDM IAD02 integrated access gateway device side interfaces

How are audio and video collaborative dispatching and video transmission implemented?

The IDM-MCC command and dispatch system can achieve coordinated audio and video dispatching, binding telephone numbers or radio set IDs of wireless intercoms with the corresponding video, so that the sound and image of the target area can be displayed synchronously, and the dispatcher can view audio and video dispatching information synchronously on the IDM MCC dispatch console. During audio and video dispatching, video transmission is divided into two modes: IP private network video transmission and IP public network video transmission. The IP private network has sufficient bandwidth and can transmit high definition images; the IP public network uses WiFi access, and the portable video terminal can directly insert a SIM card or be equipped with a wired-to-WiFi wireless router, supporting 3G and 4G access from the three major carriers. In private network scenarios, wireless bridges in the 450M, 900M, 2.4G, and 5.8G frequency bands can be used for coverage; the 450M COFDM wireless bridge supports non-line-of-sight (NLOS) long-distance transmission (1080km) and has strong penetration capability, while the 900M wireless bridge has non-line-of-sight transmission capability and line-of-sight (LOS) transmission of 35km; for different environments such as airports and firefighting, wireless bridges should be selected according to coverage distance and bandwidth requirements.

Figure 30: Portable video terminal device appearance — SIM card insertion supports IP public network video access

Figure 31: Portable video terminal field application example — audio and video collaborative dispatching scenario

Figure 32: Portable video terminal and system interface application illustration — mobile job role audio and video access

Board and interface details: VHF radio interface card and trunking control card

The audio signal of the VHF radio interface card is a 600Ω balanced output or input, adjustable from -30dBm to +10dBm; the VHF radio control signal PTT is normally a positive DC voltage to ground, and when activated, the positive voltage is connected to ground. When VHF equipment is connected to access equipment, the interface standard requires E&M signaling to be Type II or Type V, and to comply with China's communications industry standard D610-93; air traffic control VHF interfaces also require that line transmission bit errors do not affect radio operation, E1 line loopback alarms and release, multiple E&M interfaces controlling the same radio without affecting each other, and VHF radio continuous transmission time not exceeding 2 minutes. When multiple PCM equipment control the same VHF interface, different equipment may have different power supply voltages and different E&M control circuits. The E&M interface of the IDM M9000B communication command and dispatch system adopts voltage-difference threshold redundancy or anti-backfeed components to prevent false operation of the control line.

Figure 33: IDM M9000B Board Introduction — VHF Radio Interface and E&M Signaling Access Diagram

The trunking control card is similar to the VHF interface card, and both belong to the E&M category of interfaces; there are many types of trunking radio sets with diverse interface voltages, so the trunking control card adopts a design that partially polarizes the interface voltage without distinguishing voltage magnitude, making it compatible with various trunking radio set interfaces. The IDM M9000B communication command and dispatch system also adopts line signaling filtering, port voltage difference elimination modules, and other processing to ensure stable trunking and radio control signals.

Figure 34: Trunking Control Card Physical View and Interface Example — Multi-Format Trunking Radio Set Access

Figure 35: Application Example of Trunking Control Card Adapting to Different Formats of Trunking Radio Set Interfaces

The complete IDM M9000B communication command and dispatch system consists of a main unit, interface boards such as VHF and trunking, and supporting devices such as dispatch consoles, SIP gateways, and video terminals. The IDM-MCC21 multimedia dispatch console can serve as a typical supporting terminal for a command center operator seat and work in coordination with the main unit.

Figure 36: IDM-MCC21 Multimedia Dispatch Console Live Photo — Command Center Multimedia Dispatch Terminal

Typical Application Scenarios

Military and Police Counter-Terrorism and Stability Maintenance and Emergency Command

Military, police, and emergency command scenarios require establishing a unified voice command system under conditions where multiple sites and multiple formats coexist. The IDM M9000B communication command and dispatch system can connect HF radio sets, VHF radio sets, 350M and 800M trunking intercom, fixed-line telephones, magneto telephones, and satellite phones to the same platform, with a single unit connecting up to 48 radio channels or 120 telephone terminals; when a field command post has no stable mains power, the equipment is powered by an 11V~15V DC rechargeable battery or vehicle power supply, is small in size, easy to carry in a vehicle, and can be enabled upon wiring on site. This feature also makes it an ideal choice in military emergency communications vehicle solutions. During counter-terrorism and stability maintenance and disaster relief, commanders quickly initiate conferences and broadcast alarms through one-touch direct dispatching, group calls, and pre-defined plan buttons, and the situations of each detachment are summarized to the same dispatching seat.

Rail Transit and Airport Air Traffic Control Dispatching

Dispatch communications for rail transit and airports require establishing stable voice channels between stations, sections, depots, hangars, and the dispatch center. The IDM M9000B communication command and dispatch system interfaces with existing transmission and switching equipment through 2 groups of E1 interfaces using No.1, SS7, and PRI signaling, and can also be cascaded with Raytrans transmission and access equipment to extend dispatch voice channels to remote stations along the optical transmission network; airport air traffic control VHF interfaces have clear requirements for E&M signaling type, line bit errors, and loopback alarms. The VHF radio interface card of the IDM M9000B is designed according to E&M signaling Type II or Type V and complies with the D610-93 standard. When multiple PCM equipment control the same VHF interface, voltage-difference threshold redundancy is adopted to prevent false operation, making it suitable for the access requirements of air traffic control intercom and apron dispatching.

Energy, Electric Power, and Petrochemical Industrial Private Networks

Dispatch communications for industrial production private networks such as electric power and petrochemicals have clear requirements for channel determinism and anti-interference. The IDM M9000B communication command and dispatch system is based on TDM time-slot switching, with each call occupying a fixed 64K time slot, reserved bandwidth, and never meeting a busy line, and is not affected by IP broadcast storms and burst traffic; sites such as plants, substations, and oilfields can converge telephone, intercom, and radio voice channels into the same dispatching platform via E1, PCM, and optical fiber, and magneto telephones and 2100Hz in-band signaling terminals can also be connected. The system supports communication fault alarms and fault log management, multi-level permission management, and command recording traceability, facilitating the daily management of production dispatching and emergency response.

Selection and Deployment Recommendations

The IDM M9000B converged communication command and dispatch system is suitable for group command scenarios that require unified command and dispatch of multi-format radio sets, trunking intercom, wired telephones, and IP terminals. During deployment, select interface cards and supporting devices according to the number of radio channels, number of telephone channels, and number of remote stations: for single-point command and dispatch within 48 radio channels or 120 telephone channels, a single main unit can be selected; for cross-regional multi-point command, multi-unit networking can be done via twisted pair, E1, or IP routing, and when greater radio capacity is needed, E1 cascading capacity expansion is used, with each E1 interface capable of expanding 30 radio interface channels; when long-distance extension of magneto telephones or analog telephones is needed, an IDM-MAGgate or IDM IAD02 gateway is optional; when ring network video post deployment and mobile video inspection are needed, an optical fiber ring network and portable video terminals are optional. In terms of power supply, the main unit supports 11V15V DC and 110V220V AC, and can be used in vehicle-mounted, portable battery, and mains power scenarios.

During selection, three capabilities can be checked with emphasis: first, access capacity — whether a single unit's 48 radio channels and 120 telephone terminals can cover the current phase of services and reserve expansion margin for 2 E1 interfaces; second, architecture reliability — whether the reserved bandwidth and never-busy-line characteristics of TDM time-slot switching match the on-site requirements for channel determinism and resistance to IP broadcast storms, and private networks with high security levels should especially retain deterministic switching in the command and dispatch core; third, deployment conditions — whether 11V~15V DC power supply and built-in battery capability meet the power supply access conditions of field, vehicle-mounted, and temporary command posts, and whether the overall size and weight of the unit are convenient for rapid handling. The board combination, upper limit of conference channels, and engineering configuration parameters are not yet recorded in the knowledge base; please refer to the command and dispatch system manufacturer's technical documentation and commercial confirmation. To confirm interface configuration, networking solutions, and pricing information, please contact Beijing Ruiguang Jiyuan Digital Technology Co., Ltd.