Analyze the networking of half-digital building intercom systems

The building intercom system has evolved from an independent system to a networked system, from the development of networking through various bus systems to semi-digital networking, and further development to the use of mature TCP/IP network technology networking, from a single function type to an intelligent integrated control type. rapid. Today's building visual intercom in 2010 is integrated into our lives.

â–  Building Visual Intercom Digital The Chinese building intercom market is experiencing a transformation from analog to digital and from bus to TCP/IP networking. Before 2007, the implementation of TCP/IP building intercom products remained at the conceptual stage. By 2008, the TCP/IP intercom technology was becoming more and more mature, becoming a real product and starting to be put on the market. Many people in the industry generally believe that compared with 2007, digitization, IP networking, and integration of intercom products were clearly in a state of pervasiveness in 2008. Digitalization and TCP/IP technologies have been widely accepted in the consumer market. Semi-digital intercom products and all-digital intercom products have entered the stage of substantial application.

Through the 2008 Beijing Security Exhibition, it was found that full TCP/IP technology and semi-digital intercom products have become quite common. Many manufacturers' analog and digital combined semi-digital products attract people's attention, and some manufacturers' all-digital intercom products have become the highlights of the 2008 Beijing Security Exhibition Intercom series. It can be seen that digital intercom products have become a Talk about the important indicators of manufacturers' technological development.

For example, the Matsumoto Intelligent Digital Home 880 series is a digital building intercom system for all-IP network transmission. From the indoor extension to the door station, and then to the management center (PC), TCP/IP digital transmission is adopted. Since the network architecture is based on the IP network, Has the fastest network communication speed and a full range of home calls, in addition to a very powerful system expansion.

At this stage, although the traditional analog intercom system still occupies a large market share, its shortcomings are also becoming increasingly prominent. For example, in the wiring structure, the analog system divides the signal transmission network into a trunk bus (networking) and a branch bus (unit). Equipment from the management machine, the cell door machine, the unit door machine, the second confirmation of the door machine, the indoor extension form a hierarchical bus structure from top to bottom. The management machine-to-cell doorway unit and the unit door-to-door machine are the community-networked backbone bus, and the unit door-to-door device confirms the door machine twice and the indoor extension is the second-level branch bus. Regardless of whether it is a trunk bus or a branch bus, signal lines such as voice, video, and control need separate dedicated cables, so the types and number of cables will be large, which will cause system cost and engineering problems.

Now, semi-digital networking has become more common, namely TCP/IP networking to cell door machines, cell door machines to residential doorways and indoor devices still using the traditional bus method. It is understood that the reason is that TCP/IP networking has obvious advantages in terms of cabling, networking, signal transmission, system scalability, function scalability, system maintainability, network anti-interference, multi-channel communication capabilities, and so on. Advantage.

Compared with all-digital TCP/IP intercom system, the cabling is much less and much simpler. All kinds of signals (audio, video and control) are fully digitalized and transmitted together using only one network cable, which simplifies the wiring and enables the installation and debugging of system equipment. Maintenance is simple. TCP/IP networking can not only realize the transmission of signals such as sounds, images, and control, but also realize the complete networking of buildings and residential intercom equipment. Because the system technology is based on digitization and networking, the system can use an ARM platform with an integrated audio and video codec module. Its powerful data processing capability and bandwidth of hundreds of megabytes make the original multiple types of signals into a single digital signal, enabling signal transmission. It becomes “simple”, the signal quality is greatly improved, the anti-jamming ability is greatly improved, and it can realize seamless integration with the community perimeter alarm, access control, card, community service and other systems.

Compared with the traditional bus-based analog intercom, IP digital intercom has been highlighted as having the following characteristics: the transmission distance is not geographically limited, and the expansion and upgrade are extremely convenient; the transmitted audio and video, control and other signal effects are much better than the traditional bus. It can realize the integration of multiple functions such as home alarm, home appliance control, remote monitoring, and community service; it is easy to install and debug, shortens the project cycle, and saves project expenses.

â–  Building video intercom integrated intercom system generally includes: central management machine, wall machine, unit door machine, secondary confirmation door machine, indoor extension, etc., through a dedicated network of network.

The basic functions of the video intercom include two-way calling, video calling, door-to-door surveillance, and remote unlocking. As the development efforts increase and the user needs additional functions, the present intercom system also generates image capture storage functions. Picture message function, call recording and recording function, household access function, ladder control function, etc. And can integrate with the access control system to achieve transparent transmission of the access control system through the IP network. The following describes the functional performance of the main equipment of the intercom system.

Indoor extension: The basic functions are intercom (video intercom), (emergency) call, remote unlock. According to the function, it can be divided into two categories of intercom and video intercom products, and it can also be derived from the household message function, household pass function, ladder control function and so on.

Door machine: In addition to calling the tenants, password unlocking and other basic functions, but also need to have the function of the call management center, infrared fill light, night keyboard backlight, etc. are also necessary for the door machine. In addition, the door machine can be integrated with the access control card reader so that the intercom system can work in conjunction with the access control system. Residents can use the ID/IC card to open the door through the door machine control. Now the new door machine will also have the following additional features: image capture storage function, picture message function, advertising player function. There are even some door machine cameras that can be adjusted by the indoor unit remotely up, down, left, right, and left and right to ensure that the viewing area is large enough to be suitable for viewing high- and low-height visitors. It can be seen that the performance of the door machine is becoming increasingly sophisticated and user-friendly.

Center management machine: generally has the basic functions of calling, intercom, and alarm receiving, and is the basic equipment of the community intercom system. If the center manager is connected to a computer or directly uses a computer as a management center, the functions of the building intercom system can be greatly expanded. Now many manufacturers have spared no effort in the management of the software, make the management machine has integrated three table copying, information release, information query, alarm record query and other functions.