China Mobile HeDuiJiang is a public-network Push-to-Talk over Cellular service. It uses mobile operator networks and dedicated smart intercom terminals to provide wide-area group communication. For field teams, patrol users, municipal services, logistics staff, temporary project groups, and public service units, this type of PoC communication is easier to deploy than a traditional private radio network.

However, public PoC platforms are usually designed as closed service ecosystems. They work well for terminal-to-terminal group communication inside the operator platform, but they are not always designed for deep customer customization or direct integration with third-party command dispatch systems.

In many emergency communication, industrial dispatch, public safety, utility, transportation, and security projects, users do not only want to talk inside a PoC group. They also need to connect PoC terminals with dispatch consoles, SIP phones, IP voice systems, private radio channels, recording servers, GIS platforms, alarm linkage, and unified command workflows. This is where a RoIP gateway becomes useful.

Why PoC integration is needed in dispatch projects

PoC intercom is convenient because it uses cellular data networks and cloud platform services. Field personnel can press the PTT key and talk with users in the same group without building repeater stations, private base stations, or dedicated radio coverage. For wide-area work coordination, this is a practical advantage.

The limitation appears when the command center needs cross-system communication. A dispatch room may already operate SIP dispatch software, IP phones, industrial telephones, private radio channels, video systems, recording platforms, duty consoles, and emergency call points. If the PoC system remains isolated, dispatchers may need to hold a separate PoC terminal or manually relay messages between systems.

This creates unnecessary delay and makes event records harder to manage. The real project requirement is not simply “use PoC intercom.” It is to make PoC intercom part of a converged communication workflow, so dispatch operators can talk with PoC groups, receive field voice, bridge public and private radio users, and coordinate response actions from one interface.

RoIP gateway as the practical access bridge

A RoIP gateway provides a practical way to connect public PoC terminals with command dispatch systems. Instead of modifying the operator’s PoC cloud platform, the gateway works at the terminal access layer. It connects to the PoC terminal through a dedicated cable interface, receives voice and PTT control signals, and converts the communication into SIP or IP-based voice resources.

This method is especially useful when the public PoC service does not provide open dispatch integration interfaces. The PoC terminal remains logged into its original operator group, while the RoIP gateway makes that terminal available to the SIP dispatch system as a callable communication channel.

The original solution often uses a dedicated hardware interface such as a 9-pin aviation connector. Through this connector, the gateway can handle audio input, audio output, PTT control, and terminal-side intercom communication. After conversion, the dispatch system can call the gateway port and communicate with the corresponding PoC group.

How the connection works

The working principle is straightforward. The PoC intercom terminal connects to the operator’s public-network PoC group through mobile data. At the same time, the terminal is connected locally to the RoIP gateway through a matching cable. The gateway connects upstream to the command dispatch system through an IP network or SIP registration.

When a dispatcher needs to talk to the PoC group, the dispatch console calls the SIP number or port number assigned to the RoIP gateway. After the call is connected, the gateway activates the PoC terminal and sends the dispatcher’s voice into the PoC group. Field users hear the dispatch instruction just like they would hear another intercom user in the same group.

The reverse direction works in the same way. When a PoC user presses PTT and speaks, the RoIP gateway receives the terminal-side voice and sends it to the dispatch platform. The dispatcher, SIP phone, or command console can then hear the PoC group audio in real time.

Typical system components

A complete access solution usually includes the PoC intercom terminal, a matching connection cable, a RoIP gateway, an IP network, a SIP server or dispatch platform, and active operator-side PoC service coverage. The PoC terminal remains responsible for joining the public-network intercom group. The gateway is responsible for audio, control, and protocol conversion.

The dispatch platform does not need to understand the internal logic of the operator PoC system. It only needs to manage the gateway port as a communication resource. This simplifies integration and allows existing dispatch systems to communicate with public PoC users without rebuilding the PoC platform itself.

Bridging public PoC and private radio systems

The same access method can also bridge public PoC intercom with private radio communication. Many projects already have VHF, UHF, PDT, DMR, analog radio, or other trunked radio systems. At the same time, some users may rely on public PoC terminals because they work across a wider area or do not have access to the private radio network.

A two-port RoIP gateway can support a simple bridging model. One port connects to a private radio terminal, and the other port connects to a public PoC terminal. After the gateway or dispatch platform is configured, the two communication groups can exchange voice without forcing users to change their original terminals.

Private radio users continue using existing radios. PoC users continue using public-network intercom terminals. The gateway handles cross-system audio and PTT conversion. This approach is useful for emergency response, public safety coordination, industrial site support, temporary events, and projects where several communication systems must work together.

Operation flow in the dispatch center

From the dispatcher’s point of view, the workflow should remain simple. The operator does not need to manually pick up a PoC terminal every time. The dispatcher selects or calls the gateway port from the dispatch console. Once connected, the gateway activates the corresponding PoC terminal channel and creates a voice path between the dispatch system and the PoC group.

This makes the operation close to normal dispatch calling. The duty operator can handle PoC users, SIP users, private radio users, industrial telephones, emergency call points, and paging resources from one dispatch interface instead of switching between multiple separate devices.

When combined with a converged communication platform, the same interface may also support call recording, incident records, group dispatch, emergency priority, alarm linkage, and response coordination. For projects that need cross-network voice dispatch and radio integration, Becke Telcom / 贝克通信 can be considered as a practical solution reference.

Network architecture for field deployment

A typical deployment includes the public PoC terminal on one side and the command dispatch network on the other side. The PoC terminal communicates with its original operator platform through the mobile network. The RoIP gateway connects locally to the PoC terminal through a dedicated cable and connects upstream to the dispatch platform through IP networking.

For single-channel projects, one gateway port may correspond to one PoC group. For larger projects, multiple gateway ports can connect several PoC terminals, private radio channels, or special communication groups. The dispatch system can then assign these resources to different departments, duty seats, incident types, or response workflows.

Although the access principle is simple, reliable deployment still depends on careful engineering. The project team should confirm IP address planning, SIP registration mode, port mapping, audio codec selection, PTT timing, network delay, recording requirements, power backup, and failover strategy.

Benefits for converged communication projects

The first benefit is interoperability. A closed public PoC platform can be connected to a command dispatch system without rebuilding the entire communication structure. This protects existing terminal investment while improving command-center control.

The second benefit is easier implementation. By using terminal-side access, custom cables, and gateway port configuration, the project can adapt to different PoC terminals and radio models. This reduces dependence on platform-level customization and makes field deployment more practical.

The third benefit is operational consistency. Dispatchers can handle public PoC users, private radio users, and IP voice users from one platform. This improves response efficiency, reduces manual message relay, and makes recording and incident review easier to manage.

Engineering points that should be tested

Before deployment, engineers should confirm the exact PoC terminal model, connector definition, audio input and output levels, PTT control method, gateway port quantity, SIP registration mode, and dispatch platform compatibility. Different terminal models may require different custom cables, so interface verification should be completed before site delivery.

Audio tuning is also important. If the input gain is too high, the dispatch side may hear distortion. If the output gain is too low, field users may not hear the dispatcher clearly. Both directions should be tested: dispatcher-to-PoC voice and PoC-to-dispatch voice.

PTT timing must be checked carefully. Some terminals need a short activation time before audio transmission begins. If the gateway sends audio too quickly, the first syllable may be clipped. If the delay is too long, communication may feel slow. Proper timing configuration can make the system feel more natural during daily use.

Where this solution is useful

This solution is suitable for emergency command centers, urban management, transportation operations, industrial parks, energy sites, security dispatch, temporary event support, public service coordination, utility maintenance, and projects that already use public PoC terminals but need command-center integration.

It is also suitable for hybrid communication environments. For example, an emergency team may use private radios inside a local site, while external support teams use PoC terminals across a wider area. A RoIP gateway can connect both sides so that the command center can coordinate them through one dispatch system.

In many real projects, the value is not the gateway device alone. The value is making isolated communication resources usable inside a coordinated command workflow. Once PoC, private radio, SIP voice, and dispatch terminals can work together, the command center gains a clearer and more controllable communication structure.

Summary

Connecting China Mobile HeDuiJiang or similar public-network PoC intercom services to a command dispatch system is practical when a RoIP gateway is used as the access bridge. The gateway connects to the PoC terminal through a dedicated interface, receives voice and PTT control, converts the communication into SIP or IP voice, and allows the dispatch system to call and communicate with the PoC group.

The same method can also bridge private radio and public PoC groups. With a two-port RoIP gateway, one port can connect to a private radio terminal and another port can connect to a PoC terminal, allowing two originally separate communication groups to interoperate. This provides a simple, flexible, and project-friendly method for solving the access problem of closed public-network intercom platforms in converged communication systems.

FAQ

Does a RoIP gateway require changes to the public PoC platform?

Usually no. The gateway-based method works through terminal-side voice and control access. It does not depend on deep modification of the public PoC cloud platform, which makes it easier to deploy in practical projects.

Can one gateway connect multiple PoC groups?

Yes. If the gateway has multiple ports and each port is connected to a separate PoC terminal or channel, each terminal can remain in a different group. The dispatch system can then manage them as different communication resources.

What should be checked before making a custom cable?

Engineers should confirm the terminal connector type, pin definition, audio input and output levels, PTT control pins, ground reference, and whether the terminal needs special accessory detection. Incorrect wiring may cause poor audio or failed transmission.

Can PoC and private radio users talk to each other?

Yes, they can interoperate through a gateway-based design. The actual communication behavior depends on the radio systems involved. Many PTT systems are half-duplex, so speaking order, PTT timing, and gateway control logic should be tested before formal deployment.

Is this solution suitable for emergency command applications?

Yes, but it should be tested under real operating conditions. Emergency projects should verify network availability, audio clarity, gateway stability, power backup, recording, dispatch permissions, and fallback communication methods.