IDM Voice_DUP Voice Channel Mutual Backup Switching Device
One Channel Split into Two, Triple Optimal Selection by Level, Time and Content, Automatic Switchover on Link Failure
Some important remote dispatch and control sites (such as subways, airports and military facilities) often require extremely high system reliability, and often carry services over two or more transmission networks (for example, leasing channels from China Unicom and China Mobile respectively, or mutual backup between satellite and terrestrial networks)
The IDM Voice_DUP one-channel-to-two-channel voice channel mutual backup switching device is a voice channel optimal path selection switching device on the user side, developed by Beijing Ruiguang Jiyuan Digital Technology Co., Ltd. It is used to split one audio channel into two paths for transmission, to automatically detect the transmission link quality of these transmission channels at the remote end, and then to automatically select the one path whose transmission is normal. As a professional SDH equipment manufacturer, Raytrans has launched this voice channel mutual backup switching device, which achieves reliable mutual backup of voice channels in SDH transmission networks.
At remote dispatch and control sites such as subway dispatch, airport ground dispatch and military remote command, the same service is usually carried over two or more transmission networks, for example by leasing channels from China Unicom and China Mobile respectively, or by mutual backup between satellite and terrestrial networks, and the subscriber terminal is required to be able to automatically select the normal transmission network and channel. As a command and dispatch system manufacturer, Raytrans provides voice channel mutual backup switching devices that are widely used in scenarios such as subway dispatch and airport ground dispatch, and also provide reliable voice channel mutual backup switching protection for military emergency communications vehicle solutions and government private network optical fiber communication solutions.
Key specifications at a glanceOne Channel Split into Two · 3U Dual Power Supply · Network Management Switchover · Manual Priority · Cascading Expansion to More Paths · 4 Sets of Channel Selectors for the Desktop Device
How Does the One-Channel-to-Two-Channel Voice Channel Mutual Backup Device Reduce Service Interruptions Caused by Transmission Failures?
The IDM Voice_DUP splits one audio channel into two paths for transmission, supports more paths through cascading expansion, and performs automatic switchover on link failure, after which the still-normal path continues to carry voice, mainly in order to reduce service interruptions caused by transmission path failures or equipment failures. The voice channel switching requirements of the dispatch private networks of subways, airports and the military are the main application scenarios for this type of device.
- Splitting: the same audio channel is split into two paths after being fed into the device and sent to two different transmission networks respectively; when more paths are needed, cascading multiple devices provides the expansion.
- Detection: the remote end continuously detects the transmission link quality of these transmission channels, identifying both a broken line and a case where the line is still transmitting but the voice content is already incomplete.
- Optimal selection: the one path with a normal detection result is selected as the output, and the subscriber terminal is always connected to a usable channel without manual rewiring.
IDM series products can meet the multi-path transmission and active optimal path selection transmission requirements of E1 channels, telephone channels, pure audio channels and RS232/RS485 channels, and the same optimal selection approach can cover the multi-path bearing requirements of voice and data. In a dispatch private network, voice channel automatic switchover devices are generally installed on the subscriber interface side, and after the service is accessed from the switch or telephone side, the device performs splitting and optimal selection.
What Does the Voice Channel Mutual Backup Switching Device Rely on to Determine the Integrity of a Voice Channel?
The IDM Voice_DUP one-channel-to-two-channel voice channel mutual backup device determines the integrity of the voice channel by monitoring the signal level in the transmission line and, together with time alignment and content comparison, detecting the transmitted content of the voice channel; this set of criteria is also the basis for automatic optimal selection and switchover.
- Signal level monitoring: the voice signal level in the transmission line is continuously collected; when the level falls outside the normal range, it indicates that this link or device is already abnormal.
- Time alignment: the timing relationship of the several transmissions is checked to determine whether the data of each path is still delivered according to the same time reference.
- Content comparison: the voice content returned over the several paths at the same moment is checked for consistency, identifying a case where the link is still transmitting but the content is distorted.
The three types of criteria are used in combination, which makes it possible to identify not only link interruption but also voice content distortion caused by equipment failure or link degradation, reducing the misjudgments that easily occur when only link alarms are observed. The device can also be used at the remote end as an audio line detection device, reporting the detected line state in the manner of an IoT terminal.
How Do Automatic Switchover, Network Management Switchover and Manual Switchover Work Together?
The device supports automatic switchover, network management switchover and manual switchover at the same time; the current mode is indicated by the mode indicator lights on the front panel, and the mode can be set either from the network management system or controlled by the mode switching button on the front panel.
- Automatic switchover: the path with normal transmission is automatically selected according to the preset switching conditions, requiring no manual intervention in daily operation.
- Network management switchover: the monitoring and switchover of the voice channel are implemented through the Ethernet network management, and the switching conditions are set by the network management system.
- Manual switchover: manual forced switchover is available from the network management system or the DIP switch; manual switchover has a higher priority, that is, manual priority.
For centralized equipment, the monitoring and switchover of the voice channels are all performed on the network management system, and the on-duty personnel can see the transmission status of each voice channel and issue switchover commands remotely. The desktop device provides 4 sets of Voice mutual backup channel selectors, and the 4-position DIP switch on the device controls manual switchover of channels 1-4 respectively; manual switchover is possible only when the manual switching indicator light is illuminated.
What Form Factors and Configurations Do the Centralized and Desktop Devices Have?
The IDM Voice_DUP has two form factors, the desktop device and the centralized device, which can be selected according to the needs of centralized equipment room management or local operation. The centralized equipment has a 3U architecture with a unified Ethernet network management card and dual power cards in mutual backup, and the monitoring and switchover of the voice channels can all be implemented through the network management.
Figure 1: IDM Voice_DUP Voice Channel Mutual Backup Switching Device, Close-Up of the Mode Indicator Lights and Dual Power Cards on the Front Panel of the 3U Centralized Enclosure
The desktop device is smaller in size and has 4 built-in sets of Voice mutual backup channel selectors, making it suitable for sites where only one or a few points need manual intervention. For equipment rooms that require centralized management, the 3U centralized voice mutual backup device can be selected, concentrating the switchover of multiple voice channels on one device for unified monitoring.
Figure 2: IDM Voice_DUP Voice Channel Mutual Backup Switching Device, Close-Up of the 4-Position DIP Switch and Channel Indicator Lights on the Desktop Device
What Are the Main Functions?
| Function | Description |
|---|---|
| One Channel Split into Two for Transmission | Splits one audio channel into two paths and feeds them into two different transmission networks respectively; after cascading, it can be expanded to more paths |
| Link Detection at the Remote End | Performs automatic detection of the transmission link quality of these transmission channels at the remote end, providing the basis for optimal selection |
| Voice Integrity Determination | Determines the integrity of the voice channel through signal level monitoring, time alignment and content comparison |
| Automatic Optimal Selection and Switchover | Automatically selects the one path with normal transmission, reducing service interruptions caused by transmission path failure or equipment failure |
| Network Management Switchover | The monitoring and switchover of the voice channel are performed through the Ethernet network management, and the switching conditions are set by the network management system |
| Manual Forced Switchover | Manual forced switchover is available from the network management system or the DIP switch, and manual switchover has a higher priority |
| Mode Indication and Control | The automatic, network management and manual modes are indicated by the mode indicator lights on the front panel and can also be controlled by the mode switching button on the front panel |
| Audio Line Detection and Reporting | Can serve as an audio line detection device at the remote end and report the monitoring data in the manner of an IoT terminal |
Performance and Technical Specifications
| Item | Parameter/Specification | Description/Applicable Conditions |
|---|---|---|
| Device Model | IDM Voice_DUP | Voice Channel Mutual Backup Switching Device |
| Splitting Capability | One audio channel split into two paths for transmission, supporting more paths after cascading | Configured according to the number of transmission networks that need to carry services at the same time on site |
| Detection Criteria | Signal level monitoring, time alignment, content comparison | Used to determine the integrity of the voice channel |
| Centralized Form Factor | 3U architecture, unified Ethernet network management card | Dual power cards in mutual backup, suitable for centralized deployment in equipment rooms |
| Desktop Form Factor | 4 sets of Voice mutual backup channel selectors | The 4-position DIP switch controls manual switchover of channels 1-4 respectively; manual switchover is possible only when the manual switching indicator light is illuminated |
| Switchover Modes | Automatic switchover, network management switchover, manual switchover | Manual switchover has a higher priority |
| Applicable Services | E1 channels, telephone channels, pure audio channels, RS232/RS485 channels | The IDM series supports multi-path transmission and active optimal path selection transmission |
| Applicable Sites | Subway dispatch private networks, airport ground dispatch, military remote command | Remote Dispatch and Control Sites |
| Power Supply and Power Consumption | Not yet recorded in the knowledge base | The manufacturer's technical documentation shall prevail |
Differentiated Value
| Differentiation Point | Customer Value |
|---|---|
| One channel split into two: one audio channel is split into two paths for transmission | One audio channel split into two paths for transmission, cascading expansion to more paths, automatic switchover on link failure, critical circuit services uninterrupted |
| Signal level + time alignment + content comparison | Monitoring signal level + time alignment + content comparison to accurately determine the integrity of the voice channel |
| 3U dual power supply: 3U centralized dual power cards in mutual backup | 3U centralized dual mutual-backup power supplies, with unified monitoring and switching condition setting on the network management system |
| Network management switchover, manual priority | The switching conditions are set by the network management system; manual forced switchover is available from the network management system or the DIP switch, and manual switchover has a higher priority |
Typical Application Scenarios
Figure 3: IDM Voice_DUP Voice Channel Mutual Backup Switching Device, Schematic Diagram of the Networking Topology for One-Channel-to-Two-Channel Dual-Channel Mutual Backup
Subway Dispatch Private Network
Subway dispatch carries the voice of train dispatch, electric power dispatch and environment control dispatch, and multi-network redundancy is a routine requirement. Subways often lease channels from two carriers at the same time, sending the dispatch voice to stations and depots over two networks respectively; the one-channel-to-two-channel voice channel mutual backup switching device splits one dispatch audio channel into two paths and sends them out at the station side, and the remote end judges which path is available according to the signal level and content comparison and performs automatic optimal selection, so that when one of the two links fails or degrades, the dispatch voice still falls on the normal path.
The centralized 3U device is placed in the communications equipment room, with dual power cards in mutual backup and the switching conditions set uniformly by the network management system, so the duty operator can view the status of each voice channel on the network management system. On subway lines with many stations that require unified management, using one centralized device to carry the optimal selection of multiple voice channels makes routine maintenance more convenient.
Airport Ground Dispatch
Airport ground dispatch provides coverage of the voice and public address of positions such as apron guidance, passenger services and ground support, and the interruption of any channel will affect the pace of flight support. Airports usually have both a self-built optical transmission network and leased channels, and in some scenarios satellite links are also used as a supplement; the one-channel-to-two-channel voice channel mutual backup switching device feeds the same dispatch audio channel into two links at the same time, and the remote end performs automatic detection and selects the normal one for output, reducing the impact of a single link or single device failure.
Sites with higher requirements can expand more paths by device-level cascading expansion and retain a manual forced switchover entry, so that the on-duty personnel can directly designate the path when a dispute arises. For flight support positions, the switchover process requires no on-site rewiring, and the duty operator can see the channel status on the network management system.
Military Remote Command
Military remote command has high requirements for redundancy and controllability, and mutual backup between satellite and terrestrial networks is often used to carry command voice. The voice channel mutual backup switching device performs splitting and transmission at the command post side and optimal selection and reception at the remote end, determining channel integrity according to the results of signal level and content comparison, so that command voice can still be delivered when link quality changes.
The device supports three switchover modes: automatic, network management and manual, and manual switchover has a higher priority, making it convenient to directly designate the channel according to the command relationship in a combat readiness state; the desktop device has 4 built-in sets of channel selectors, suitable for field or mobile command points that require local operation.
