Rssearch And Design Of WIFI Video Transmission Based On STM32

With the development of the WIFI technology, its mature technologies are comprehensively applied in smart phones and computers which are necessary in daily life.Popularization of electronic equipment with the WIFI function makes embedded equipment that can connect WIFI become the focus of people. With the STM32 microprocessor chip embedded with the Cortex-M3 kernel as the core, this design realized wireless video transmission without any operating system. The overall design has advantages of small volume, low energy consumption and low cost. Based on the WIFI technology, video transmission transmits collected image data to the computer terminal in a certain frame rate with the wireless method and show real-time on-site videos on the computer terminal.Compared to the cable transmission method, application of the WIFI technology is more popular. Besides, it is more convenient in network construction and has better mobility and extensibility.Based on researches on the WIFI technology and network construction structures,software and hardware design is carried out. In the aspect of hardware, according to characteristics of STM32, the required peripheral circuits is designed and the CMOS surveillance camera OV2640 to collect video images is used. The circuit of WIFI transmission is carried out by the wireless chip Marvell 88W8686 that supported the IEEE802.11g/b standard to realize communication with main control chips through SDIO interfaces. In the aspect of software, library functions were used in the disposition of the STM32 microprocessor. According to the requirements, the Lwip protocol stack and the Marvell 88W8686 driver were selectively transplanted in bare machines to the STM32 microprocessor, so as to realize bottom drive and application layer interface design.Transplant of the WIFI drive was carried out by the researches on principles of WIFI and standard models of drives, realizing the download of firmware and normal communicationof WIFI. On this basis, the video transmission based on wifi technology is designed, and the video transmission in campus network is solved. The upper monitor program was programmed on the basis of the MFC library function and was the computer client on the basis of Socket.Finally, tests and analyses were carried out. Experimental results showed that software and hardware parts of the whole design operated stably. The WIFI part could realize three network combination modes, and transmit video images stably. It could realize real-time presentation on the computer terminal, achieving the expected purpose.