A cloud card-based digital intercom system and method

Abstract

The application provides a cloud card-based digital intercom system and method, comprising a cloud card platform, a PoC intercom platform and a PoC digital intercom; the cloud card platform interfaces with multiple operator networks worldwide to form a shared data flow pool, and the cloud card platform establishes connections with the PoC intercom platform and the PoC digital intercom through a public network, provides data flow for the PoC intercom service in the form of cloud service, and the PoC digital intercom is connected with the PoC intercom platform to realize the PoC intercom service; the cloud card platform has a server, a SIM card library and cloud card software. The cloud card platform enables the PoC intercom to select the optimal local mobile operator network according to the PLMN and signal strength of multiple operators in the location of the PoC intercom, so that the PoC intercom can realize wider coverage and select the operator network with the optimal signal, and the data flow of each PoC digital intercom can be shared.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of digital intercom, and particularly relates to a digital intercom system and method based on a cloud card. BACKGROUND

[0002] The existing digital intercom system mainly has two modes, i.e., a mode based on a wireless private network standard and a mode based on public network data flow to realize intercom.

[0003] Problems existing in the wireless private network intercom system mainly include: 1) limited intercom range, no matter a direct mode without a transfer station and a private network base station or a transfer and cluster mode using a transfer station and a private network base station, the reliable intercom range between digital intercoms is limited, and intercom service cannot be realized in places not covered; 2) high price of professional terminals, especially private network cluster digital intercoms, resulting in that many ordinary users have to consider public network digital intercoms with cheaper cost; 3) high cost of infrastructure maintenance, since the actual number of intercom users is much less than that of public network mobile phones, and these users are all self-using, therefore, under the condition of using a transfer station, a base station and other private network infrastructure, the users have to spend a large cost and price to maintain the network.

[0004] Obviously, the public network digital intercom has obvious advantages compared with the private network digital intercom, such as low cost and wide coverage (normal intercom can be realized as long as there is a public network base station of an operator), but the type of digital intercom also has obvious shortcomings, mainly including: 1) complex setting of digital intercom terminals, such as different APN settings for different operators in different countries, especially for simple digital intercoms without a display screen and a digital keyboard; 2) since the problem of operator flow rate and PoC intercom platform usage fee is involved, the problem of renewal is involved in this mode, which is completely different from the usage mode of the private network digital intercom; 3) once a certain operator is selected, the problem of poor coverage of a single operator base station in some places still exists; 4) if the public network intercom uses 2 SIM cards to select 2 public network operators, it involves the problems of high data flow rate and manual selection of different SIM cards for intercom; 5) when using an ordinary PoC public network digital intercom system, the transaction mode between the intercom system manufacturer and the customer becomes more complex, i.e., from two-party transaction (intercom system manufacturer, customer) to three-party or four-party transaction (intercom system manufacturer, customer, public network operator, PoC intercom platform operator), so that the customer is afraid of this transaction mode, which hinders the development of the PoC public network intercom industry to some extent. SUMMARY

[0005] In order to overcome the shortcomings of the prior art, the present invention aims to provide a digital intercom system and method based on cloud cards to overcome the defects in the prior art.

[0006] To achieve the above objectives, this invention provides a cloud-based digital intercom system, comprising a cloud card platform, a PoC intercom platform, and a PoC digital intercom; wherein, the cloud card platform connects to multiple global operator networks to form a shared data traffic pool, and the cloud card platform establishes connections with the PoC intercom platform and the PoC digital intercom via public networks respectively, and the PoC digital intercom connects with the PoC intercom platform to realize PoC intercom services; the cloud card platform has a server, a SIM card library, and cloud card software, wherein the server and the SIM card library are located in the data center of a cloud service provider, and the cloud card... The software is embedded in the PoC digital walkie-talkie. Based on the cloud card software, the PoC digital walkie-talkie communicates with various global operator networks that are connected to the cloud card platform. At the same time, it connects with the PoC walkie-talkie platform to realize walkie-talkie communication based on cloud card data traffic. The PoC digital walkie-talkie has a hardware platform and cloud card software. The PoC digital walkie-talkie connects with the cloud card platform by running operating system software, driver software and cloud card software on its hardware platform. The PoC digital walkie-talkie connects with the PoC walkie-talkie platform and provides a human-machine interface by running PoC application software on its hardware platform.

[0007] Through the above technical solution, the cloud card platform utilizes SIM card virtualization technology and leverages the internet and cloud computing technologies to unify various SIM cards from different operators worldwide into a unified cloud card, forming a shared data traffic pool. This pool provides data traffic for PoC (Programmable Communication) walkie-talkie services via cloud services. By using the shared data traffic of the cloud card platform, PoC digital walkie-talkies can utilize shared data traffic from multiple operators, achieving data traffic sharing. This avoids situations where some users have excess data while others have insufficient data, thus further saving on data costs. It also enables wider coverage, extending to the base station coverage of all operators connected to the cloud card platform. Furthermore, it eliminates the need for complex operations such as purchasing SIM cards and setting APNs with operators, achieving "power on and use," simplifying the use and maintenance costs of PoC public network walkie-talkies.

[0008] As a further explanation of the cloud-based digital walkie-talkie system described in this invention, preferably, the cloud card is a SIM card image file corresponding to a physical SIM card in the SIM card library of the cloud card platform. User identification during communication using the operator's network is achieved through cloud card software built into the PoC digital walkie-talkie. For a single-card PoC digital walkie-talkie, it has a unique IMEI / MEID identification code, which can correspond to multiple cloud cards.

[0009] With the above technical solution, PoC digital walkie-talkies do not require the installation of a physical SIM card or the setting of an APN, greatly simplifying their use.

[0010] As a further explanation of the cloud-based digital intercom system described in this invention, preferably, the PoC intercom platform is a business platform built on the public network to realize voice / SMS intercom, including a network management system, a PoC server system, and a scheduling system connected in pairs. The network management system, the PoC server system, and the scheduling system realize public network intercom services through a complete set of communication protocols and signaling exchanges, including realizing various intercom calls such as voice / SMS group calls, individual calls, all calls, and broadcast calls, as well as conventional functions such as alarms, remote stun, remote kill, wake-up, remote monitoring, environmental monitoring, and forced disconnection / insertion. The system includes digital signaling services for two-way radios; the network management system is used for authentication management, configuration management, and group management of PoC digital two-way radios, and provides basic data of PoC digital two-way radios to the PoC server system; the PoC server system is used for signaling control of PoC digital two-way radios and implementation of voice softswitch two-way radio services; the dispatch system is used by the dispatch client users of the command and control center to obtain real-time device data of PoC digital two-way radios on the computer host, including location information, online status, battery level, signal strength, etc., and can initiate calls and control of PoC digital two-way radios.

[0011] Through the above technical solution, the PoC intercom platform can realize PoC intercom service for PoC digital intercoms and record the intercom information of PoC digital intercoms.

[0012] As a further explanation of the cloud card-based digital intercom system described in this invention, preferably, the operating platform of the PoC digital intercom is a mobile intelligent operating system or any embedded operating system using a 2G / 3G / 4G / 5G public network hardware platform.

[0013] The above technical solution enables the PoC digital walkie-talkie to connect with the PoC walkie-talkie platform and the cloud card platform.

[0014] As a further explanation of the cloud-based digital walkie-talkie system described in this invention, preferably, the operating platform of the PoC digital walkie-talkie is a 2G / 3G / 4G / 5G public network hardware platform, which can run a smart operating system or any embedded operating system. In some actual implementations of PoC digital walkie-talkies, this hardware platform can also be supplemented with an MCU hardware platform, which runs the smart operating system or any embedded operating system.

[0015] The above technical solution enables the PoC digital walkie-talkie to connect with the PoC walkie-talkie platform and the cloud card platform.

[0016] As a further explanation of the cloud card-based digital intercom system described in this invention, preferably, the hardware platform of the PoC digital intercom can directly control access to 2G / 3G / 4G / 5G public networks.

[0017] The above technical solution enables direct access to 2G / 3G / 4G / 5G public networks, allowing PoC digital walkie-talkies using the "SIM card-free" cloud card platform to function normally.

[0018] As a further explanation of the cloud card-based digital intercom system of the present invention, preferably, the PoC digital intercom can automatically switch to the operator network with the best signal quality.

[0019] To achieve another objective of the present invention, the present invention also provides a digital intercom method utilizing the aforementioned cloud card-based digital intercom system, the digital intercom method comprising the following steps:

[0020] Step S1): The PoC digital walkie-talkie determines whether there is a physical SIM card; if there is a physical SIM card, proceed to step S2); if there is no physical SIM card, proceed to step S5.

[0021] Step S2) Determine whether the preset setting of the PoC digital walkie-talkie is physical SIM priority or cloud card priority; if the preset setting is physical SIM priority, proceed to step S3); if the preset setting is cloud card priority, proceed to step S5.

[0022] Step S3) If the physical SIM card is set to be prioritized, then the physical SIM card will be used directly to log in to the operator's network, and the cloud card service will no longer be used;

[0023] Step S4) The PoC digital walkie-talkie uses the SIM card to access the operator's network and determines whether the PoC digital walkie-talkie has an unpaid data charge; if it has an unpaid data charge, proceed to step S8); otherwise, proceed to step S9.

[0024] Step S5) If cloud card priority is preset, then regardless of whether there is a physical SIM card, the locally stored seed SIM card can be used directly to log in to the cloud card platform.

[0025] Step S6) The cloud card platform determines the optimal operator that the PoC digital walkie-talkie should select based on the PLMN and signal strength information parameters of each operator received by the PoC digital walkie-talkie, and provides the SIM card image file (i.e. cloud card) of that operator to the PoC digital walkie-talkie.

[0026] Step S7) The PoC digital walkie-talkie uses the cloud card to log in and access the operator's network, and determines whether the PoC digital walkie-talkie has an outstanding data charge; if it has an outstanding data charge, proceed to step S8); otherwise, proceed to step S9.

[0027] Step S8) The PoC digital walkie-talkie is out of service. The system displays an overdue payment message, reminds the user to pay, and then the process ends.

[0028] Step S9) The PoC digital walkie-talkie directly logs into the PoC walkie-talkie platform;

[0029] Step S10): The PoC digital walkie-talkie uses the feedback information from the PoC walkie-talkie platform login to determine whether the local ID has an outstanding PoC service fee; if the PoC service fee is outstanding, the system will display the outstanding fee information, remind the user to pay the fee, and then end the process; otherwise, proceed to step S11).

[0030] Step S11) The PoC digital walkie-talkie downloads its own intercom information to itself from the PoC intercom platform;

[0031] Step S12): The PoC digital two-way radio runs the PoC two-way communication service;

[0032] Step S13) The PoC digital walkie-talkie determines whether it is low on power; if so, the PoC service software is terminated and the device is powered off due to low power; otherwise, return to step S12) to continue running the PoC walkie-talkie service.

[0033] The beneficial effects of this invention are:

[0034] 1. This invention uses the "shared data traffic" of the cloud card platform, which enables the PoC intercom system to use the "shared data traffic" of multiple operators, realizing the sharing of "data traffic". This can avoid the situation where "some users have excess data traffic, resulting in waste, while other users do not have enough data traffic", thereby further saving data traffic costs.

[0035] 2. The PoC digital walkie-talkie of the present invention can use the networks of multiple operators through the "cloud card platform", thereby achieving a wider coverage area. It does not require complicated operations such as installing SIM cards and setting APNs, and can automatically switch to the operator network with the best signal quality when the signal quality is poor.

[0036] 3. The PoC public network digital intercom product transaction model of the present invention will directly realize the transaction between the manufacturer and the customer, and the customer no longer needs to conduct transactions with the operator to purchase SIM cards, data traffic, etc. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure of the cloud card-based digital intercom system of the present invention.

[0038] Figure 2 This is a block diagram of the PoC digital walkie-talkie of the present invention.

[0039] Figure 3 This is a flowchart of the cloud card-based digital intercom method of the present invention. Detailed Implementation

[0040] To further understand the structure, features, and other objectives of the present invention, a detailed description is provided below with reference to the accompanying drawings. The embodiments illustrated in these drawings are for illustrative purposes only and are not intended to limit the scope of the invention.

[0041] First, please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of the cloud card-based digital intercom system of the present invention. Figure 1 As shown, the present invention discloses a cloud card-based digital intercom system, including a cloud card platform 1, a PoC intercom platform 2, and a PoC digital intercom 3; wherein, the cloud card platform 1 connects to multiple global operator networks to form a shared data traffic pool, and the cloud card platform 1 establishes connections with the PoC intercom platform 2 and the PoC digital intercom 3 respectively through the public network, and the PoC digital intercom 3 connects with the PoC intercom platform 2 to realize PoC services.

[0042] The cloud SIM card platform 1 comprises a server, a SIM card library, and cloud SIM card software. The server and SIM card library are located in the cloud service provider's data center. The cloud SIM card software is embedded in the PoC digital walkie-talkie 3. Based on the cloud SIM card software, the PoC digital walkie-talkie 3 can communicate with various global operator networks connected to the cloud SIM card platform, and simultaneously connect to the PoC walkie-talkie platform to achieve walkie-talkie communication based on cloud SIM card data traffic. The cloud SIM card platform 1 is typically developed, operated, and maintained by a dedicated cloud SIM card operator. This operator purchases a sufficient number of SIM cards and data traffic from various global mobile network operators to form a shared cloud SIM card data traffic pool. The cloud SIM card platform operator typically sells its own terminals or cloud SIM card data packages to customers. Cloud SIM Platform 1 utilizes SIM card virtualization technology and leverages the internet and cloud computing to unify various SIM cards from global operators into cloud SIM cards, forming a shared data traffic pool. This cloud service provides data traffic for PoC (Programmable Channel) walkie-talkie services. Each cloud SIM card is a SIM card image file corresponding to a physical SIM card in the Cloud SIM Platform 1's SIM card library. User identification during communication using the operator's network is achieved through cloud SIM card software embedded in the PoC digital walkie-talkie 3. Each single-SIM PoC digital walkie-talkie has a unique IMEI / MEID identifier, which can correspond to multiple cloud SIM cards.

[0043] The PoC intercom platform 2 is a public network-based platform for voice / SMS intercom services. It includes a network management system and a scheduling system connected in pairs to the PoC server system. The network management system, the PoC server system, and the scheduling system communicate via a complete communication protocol and signaling exchange to enable public network intercom services. It supports various intercom calls, including voice / SMS group calls, individual calls, all calls, and broadcast calls, as well as digital signaling services common in intercom systems, such as alarms, remote stun, remote kill, wake-up, remote monitoring, environmental surveillance, and forced disconnection / insertion. Specifically, the network management system manages the authentication, configuration, and grouping of the PoC digital intercom 3, providing basic data for the PoC digital intercom 3 to the PoC server system. The PoC server system controls the signaling and implements voice softswitch intercom services for the PoC digital intercom 3. The scheduling system allows end users to obtain real-time device data for the PoC digital intercom 3 on their computer hosts, including location information, online status, battery level, and signal strength, and enables them to initiate calls and control the PoC digital intercom 3.

[0044] The PoC digital two-way radio 3 is a handheld, vehicle-mounted, or other form of PoC public network two-way radio used by end users. It integrates a hardware platform and cloud card software. There are three main types of hardware platforms: one is a mobile smart operating system using a 2G / 3G / 4G / 5G public network hardware platform, such as a hardware platform running Android; another is an embedded operating system using a 2G / 3G / 4G / 5G public network hardware platform, such as a hardware platform running Linux; and the third is a hardware platform using a 2G / 3G / 4G / 5G public network hardware platform and an MCU (Microcontroller Unit), where the MCU can run Linux or any other embedded operating system like uCos. Regardless of the hardware platform used, the driver or operating system running on that platform must be able to directly control access to the wireless network (2G / 3G / 4G / 5G) and integrate cloud card software. This is necessary for the PoC digital two-way radio using a "SIM card-free" cloud card platform to function properly.

[0045] like Figure 2 As shown, the PoC digital two-way radio 3 connects to the cloud card platform 1 by running operating system software such as Android / Linux / uCos and driver software on its hardware platform, and through cloud card software. The PoC digital two-way radio 3 can automatically switch to the operator's network with the best signal quality. The PoC digital two-way radio 3 connects to the PoC two-way radio platform 2 and provides a human-machine interface by running PoC application software on its hardware platform, such as embedded Linux programs and Android APK software.

[0046] like Figure 3 As shown, Figure 3This is a flowchart of the cloud card-based digital intercom method of the present invention. A digital intercom method utilizing the above-described cloud card-based digital intercom system includes the following steps:

[0047] Step S1): The PoC digital walkie-talkie 3 determines whether there is a physical SIM card; if there is a physical SIM card, proceed to step S2; if there is no physical SIM card, proceed to step S5.

[0048] Step S2): Determine whether the preset setting of the PoC digital walkie-talkie 3 is physical SIM priority or cloud card priority; if the preset setting is physical SIM priority, proceed to step S3); if the preset setting is cloud card priority, proceed to step S5.

[0049] Step S3) If the physical SIM card is set to be prioritized, then the physical SIM card will be used directly to log in to the operator's network, and the cloud card service will no longer be used.

[0050] Step S4): The PoC digital walkie-talkie 3 uses the SIM card to access the operator's network and determines whether the PoC digital walkie-talkie 3 has an unpaid data allowance; if it has an unpaid data allowance, proceed to step S8; otherwise, proceed to step S9.

[0051] Step S5) If cloud card priority is preset, then regardless of whether there is a physical SIM card, the locally stored seed SIM card can be used directly to log in to the cloud card platform 1.

[0052] Step S6) The cloud card platform 1 determines the optimal operator that the PoC digital walkie-talkie 3 should select based on the PLMN and signal strength information parameters of each operator received by the PoC digital walkie-talkie 3, and provides the SIM card image file of that operator, i.e., the cloud card, to the PoC digital walkie-talkie 3.

[0053] Step S7): The PoC digital walkie-talkie 3 uses the cloud card to log in and access the operator's network, and determines whether the PoC digital walkie-talkie 3 has overdue data charges; if it has overdue data charges, proceed to step S8); otherwise, proceed to step S9.

[0054] Step S8) If the PoC digital walkie-talkie 3 is out of service, display an overdue payment message, remind the user to pay, and then the process ends.

[0055] Step S9) The PoC digital intercom 3 directly logs into the PoC intercom platform 2.

[0056] Step S10): The PoC digital walkie-talkie 3 determines whether its local ID is in arrears with PoC service based on the feedback information received when logging into the PoC walkie-talkie platform 2; if the PoC service is in arrears, it displays the arrears information, reminds the user to pay, and ends the process; otherwise, proceed to step S11).

[0057] Step S11) The PoC digital intercom 3 downloads the intercom information from the PoC intercom platform 2 to its own device.

[0058] Step S12) The PoC digital walkie-talkie 3 runs the PoC walkie-talkie service.

[0059] Step S13) The PoC digital walkie-talkie 3 determines whether the battery is low; if so, the PoC service software is terminated and the device is powered off due to low battery; otherwise, return to step S12) to continue running the PoC walkie-talkie service.

[0060] The cloud-based digital intercom system and method of this invention overcomes the shortcomings of both private network digital intercom systems and conventional public network PoC digital intercom systems. After adopting this system: 1) The coverage of the intercom is greatly expanded, extending not only to the base station coverage of a specific operator but also to the base station coverage of all operators connected to the cloud card platform; 2) The use of PoC public network intercoms is simplified, such as eliminating the need for APN settings and achieving "power on" functionality; 3) If a third-party cloud card platform is used, the maintenance cost of the PoC public network digital system is greatly reduced, as the cloud card platform will enable data traffic purchase with operators, S... 4) The transaction method between private network product manufacturers and private network customers will be simplified from the three- or four-party transaction of traditional PoC intercom services to a two-party transaction, and private network customers no longer need to transact with operators; 5) PoC digital intercoms using cloud cards can automatically switch to the operator network with good signal quality when encountering areas with poor signal quality of the current operator; 6) Since each PoC public network digital intercom using this method can "share data traffic", the problem of "some users having excess traffic leading to waste while other users have insufficient traffic" encountered by ordinary PoC digital intercom systems is avoided.

[0061] It should be stated that the above-described invention content and specific embodiments are intended to demonstrate the practical application of the technical solution provided by this invention and should not be construed as limiting the scope of protection of this invention. Those skilled in the art can make various modifications, equivalent substitutions, or improvements within the spirit and principles of this invention. The scope of protection of this invention is defined by the appended claims.

Claims

1. A digital intercom system based on a cloud card, characterized in that, This includes a cloud card platform (1), a PoC intercom platform (2), and a PoC digital intercom (3); among which, The cloud card platform (1) connects to multiple global operator networks (4) to form a shared data traffic pool. The cloud card platform (1) establishes connections with the PoC intercom platform (2) and the PoC digital intercom (3) through the public network. The PoC digital intercom (3) connects with the PoC intercom platform (2) to realize PoC services. The cloud card platform (1) has a server, a SIM card library and cloud card software. The server and the SIM card library are placed in the computer room of the cloud service provider. The cloud card software is embedded in the PoC digital walkie-talkie (3). The PoC digital walkie-talkie (3) realizes communication with the global operator networks connected to the cloud card platform (1) based on the cloud card software, and is also connected to the PoC walkie-talkie platform (2) to realize walkie-talkie communication based on cloud card data traffic. The PoC digital two-way radio (3) has a hardware platform and cloud card software. The PoC digital two-way radio (3) runs operating system software, driver software and cloud card software on its hardware platform to achieve docking with the cloud card platform (1). The PoC digital two-way radio (3) runs PoC application software on its hardware platform to achieve docking with the PoC two-way radio platform (2) and human-machine interface. The cloud card is the SIM card image file corresponding to the physical SIM card in the SIM card library of the cloud card platform (1). The user identity is identified during the use of the operator's network communication through the cloud card software built into the PoC digital walkie-talkie (3). When the PoC digital walkie-talkie (3) is a single-card walkie-talkie, the single-card walkie-talkie has a unique IMEI / MEID identification code, and the IMEI / MEID identification code can correspond to multiple cloud cards.

2. The cloud-based digital intercom system as described in claim 1, characterized in that, The PoC intercom platform (2) is a business platform built on the public network to realize voice or SMS intercom, including a network management system, a PoC server system and a scheduling system that are connected in pairs; the network management system, the PoC server system and the scheduling system realize public network intercom services through communication protocols and signaling exchanges, including realizing various intercom calls such as group calls, individual calls, all calls and broadcast calls for voice / SMS, as well as digital signaling services in conventional intercom such as alarm, remote stun, remote kill, wake-up, remote monitoring, environmental monitoring and forced disconnection and insertion; The network management system is used for authentication management, configuration management and group management of the PoC digital walkie-talkie (3), and provides the PoC server system with basic data of the PoC digital walkie-talkie (3); The PoC server system is used for signaling control and voice softswitch intercom service implementation of the PoC digital walkie-talkie (3); The dispatch system is used to instruct dispatch client users in the dispatch center to obtain real-time device data of the PoC digital walkie-talkie (3) on the computer host, including location information, online status, power level, and signal strength information, and to initiate calls and control to the PoC digital walkie-talkie (3).

3. The cloud-based digital intercom system as described in claim 1, characterized in that, The operating platform of the PoC digital walkie-talkie (3) is a mobile intelligent operating system or any embedded operating system using a 2G / 3G / 4G / 5G public network hardware platform.

4. The cloud-based digital intercom system as described in claim 1, characterized in that, The hardware platform of the PoC digital walkie-talkie (3) can directly control access to 2G / 3G / 4G / 5G public networks.

5. The cloud-based digital intercom system as described in claim 1, characterized in that, The PoC digital walkie-talkie (3) can automatically switch to the operator's network with the best signal quality.

6. A digital intercom method utilizing a cloud card-based digital intercom system as described in any one of claims 1-5, characterized in that, The digital intercom method includes the following steps: Step S1: The PoC digital walkie-talkie (3) determines whether there is a physical SIM card; If a physical SIM card is available, proceed to step S2; otherwise, proceed to step S5. Step S2: Determine whether the preset settings of the PoC digital walkie-talkie (3) prioritize physical SIM or cloud card; If the physical SIM is set to be preferred in advance, proceed to step S3; If the cloud card is set to be prioritized in advance, proceed to step S5; Step S3: If physical SIM card priority is preset, then the physical SIM card will be used directly to log in to the operator's network, and the cloud card service will no longer be used; Step S4: The PoC digital walkie-talkie (3) uses the SIM card to access the operator's network and determines whether the PoC digital walkie-talkie (3) has overdue data charges; If the data usage is overdue, proceed to step S8; otherwise, proceed to step S9. Step S5: If cloud card priority is set in advance, then regardless of whether there is a physical SIM card, the local stored seed SIM card can be used to log in to the cloud card platform directly (1). Step S6: The cloud card platform (1) determines the optimal operator that the PoC digital walkie-talkie (3) should select based on the PLMN and signal strength information parameters of each operator received by the PoC digital walkie-talkie (3), and provides the SIM card image file of the operator to the PoC digital walkie-talkie (3). Step S7: The PoC digital walkie-talkie (3) uses the cloud card to log in and access the operator's network, and determines whether the PoC digital walkie-talkie (3) has overdue data charges; If the data usage is overdue, proceed to step S8; otherwise, proceed to step S9. Step S8: The PoC digital walkie-talkie (3) is in arrears with data usage, prompts the user with the arrears information, reminds the user to pay, and then ends the process; Step S9: The PoC digital intercom (3) directly logs into the PoC intercom platform (2); Step S10: The PoC digital walkie-talkie (3) uses the feedback information from the PoC walkie-talkie platform (2) when logging in to determine whether the local ID is in arrears with PoC service fees; If the PoC service is in arrears, the system will display an overdue payment message, remind the user to pay, and then terminate the service. Otherwise proceed to step S11; Step S11: The PoC digital intercom (3) downloads the intercom information of the device to the device from the PoC intercom platform (2); Step S12: The PoC digital walkie-talkie (3) runs the PoC walkie-talkie service; Step S13: The PoC digital walkie-talkie (3) determines whether the power is low; if so, it terminates the PoC service software and shuts down due to low power; otherwise, it returns to step S12 to continue running the PoC walkie-talkie service.

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