Research And Development Of Mobile Interconnected Doorbell

With the development of the society and the economic level, people pursue a higher quality of home, demanding for a comfortable, safe and smart life, and the requirement of the smart home is also getting more and more strong. As an important part of the smart home, it goes without saying that the bell system is very important.After the analysis of the reasearch status and development tendency on bell industry found that, the traditional doorbell system had the problem of the complex layout, difficult installation and maintenance, poor scalability and so on. Combining the mobile internet with wireless LAN, by using computer network technology, embedded system, and communication network, as well as audio and video processing technology, associating the bell systems with embedded devices and handheld terminals, this paper puts a solution for the mobile internet doorbell, which get the remote control of the visual and voice intercom, monitoring and alerting, and so on.Relying on the connectivity between the wireless LAN and mobile internet,the scheme makes up the rule of the limited transmission distance of the traditional wireless doorbell, wiring less and simple, variety signal line integrated in together only with cable transmission and control. Installation, debugging and maintenance become exception simple. Signal quality will sharply upgrades and anti-interference capacity will enhance.In addition, it can be integrated with the system of community alarms, access control, One Card, community service and so on, which greatly facilitates the management and control of the home systems anywhere and anytime for people.In terms of the hardware architecture, the ARM development board supporting audio and video codec and analog-digital data interconversion module, its powerful data processing capability makes original multiple signals into a single digital signal, making it easy to signal transmission, and has USB port, serial port, Ethernet and other interfaces for future expansion needs.In terms of system platform, it adopts the open source, stable, scalable, customizable and portable linux operating system. Its hardware and software resources are abundant and the research data is numerous, which brings great convenience to research and development.In terms of the video image capture, this article follows the standard of V4L2 under the linux to develop the capture application. In terms of the image compression coding, it eventually select the MJPEG format to compress the video data in consideration of the camera output data format, the codec complexity, the embedded CPU processing ability and the compression effect and so on.In terms of the video transmission and control, voice intercom, it takes the open source protocols of the RTSP and SIP, aimed at guaranteeing the reliability and validity of video transmission, and ensuring the quality and timeliness of voice calls.After experimental verification, the mobile internet doorbell system designed in this paper gets through the performance test, and the operation effect is good, which can meet the design requirements.