The remote infrared controller designed in this paper integrates infrared transmitter module, which can control all brands of household appliances such as air conditioners and TV sets remotely through mobile phones anywhere. It also integrates wired network ports and Wi-Fi with all functions of home routers; built-in antenna can enhance Wi-Fi signals; built-in temperature sensor can realize intelligent control of air conditioning according to temperature data, and save electricity under the condition of ensuring indoor temperature comfort.
With the development of electronic technology and the growth of people’s demand for intelligent life, wireless control technology is becoming more and more important in smart home life. The remote infrared controller designed in this paper can remotely control household appliances through mobile phones, which brings great convenience to people’s lives. This system uses mobile phones to send instructions to the terminal controller through the Internet. After receiving instructions through RT5350Wi-Fi module, the terminal controller controls the closure and disconnection of relays, or forwards instructions to serial port 2. The serial port 2 of RT5350 is connected with the single chip computer, which enables the infrared module controlled by the single chip computer to send infrared signals corresponding to instructions. Remote control of household appliances by infrared signals. The temperature sensor transmits the collected temperature information to RT5350, thermostatic element and then transmits the information to the mobile phone through the Internet. The structure of the system is shown in Figure 1. The power module uses RM3273S power supply chip, RM3273S is offline PFM power management chip, and uses the original flyback topology application circuit, eliminating the optocoupler and TL431 part.
Its internal integration of high-precision constant voltage controller, can achieve no more than 5% of the precision control. RM3273S integrates a variety of protection functions, such as over-voltage protection, over-voltage clamping and under-voltage locking. In addition, built-in frequency jitter technology can improve the anti-EMI capability.
The size of the whole power module is 34 mm * 22 mm * 18 mm, which is much smaller than the general power module and can realize the miniaturization of the work.
RT5350 CPU realizes the communication between terminal equipment and server. The RT5350 CPU integrates 802.11n1*1MAC/baseband processor, 2.4 GHz 1*1 RF unit and RF power amplifier. It is a high performance MIPS 24Kc CPU core (highest main frequency 360MHz). RT5350 chip realizes the communication between CPU and server by transplanting OPENWRT embedded system, and realizes the information interaction between CPU and microprocessor by connecting with UART serial port of microprocessor. The serial port 1 of RT5350 is used to communicate with computer and is the console of RT5350 microprocessor. Serial port 2 is connected with microprocessor, and the received network information is forwarded to serial port 2. MCU receives the information of RT5350 module through UART, and then transmits the corresponding infrared signal to control household appliances. The microcontroller integrates most of the air-conditioning infrared signals.
At the same time, the microcontroller can also learn the infrared signals that have been sent to realize the control of all household appliances. Extensible USB-related products, such as USB-enabled cameras. The device can also be charged by USB. RT5350 controls the switch-off and closure of relays by receiving instructions sent by mobile phones, thus realizing the switch-off of 220V AC output. External network is connected by network port 1, and internal network is connected by network port 2. By connecting the network port 2, the computer can realize the function of accessing the external network, so that the intelligent device has all the functions of the router. OpenWRT is used in this embedded operating system. The embedded operating system is a highly automated and modular Linux embedded system with powerful network components and extensibility. The compiler and development environment of OpenWrt SDK simplifies the process of software development. The flow chart of this program is shown in Fig. 2. This design can be used for remote wireless remote control of various household appliances. It can be made into terminal products alone or embedded in household appliances to achieve remote control. By combining wireless switch controller with wireless router, redundant household appliances can be saved. This design uses RT5350 as CPU, which integrates baseband processor, RF, RF power amplifier and has comprehensive functions. RT5350 is cheap, small in size, easy to expand, and has many GPIOs, including JTAG, USB, I2C, I2S, PCM, network cable, serial port, etc. It supports multiple power supply voltages, and can be supplied with 3.3V to 6V. Wireless signal is more than other Wi-Fi SOC chips.
Stability can bring users a more smooth and stable wireless network experience. There are four infrared transmitters, which have larger signal intensity and wider coverage, and can realize 360 degree dead angle control of household appliances.
Internal integration of 220V to 5V power module, without additional step-down module. By collecting indoor temperature data information, this design can realize intelligent control of the output temperature of air conditioning, and save energy on the premise of ensuring the appropriate indoor temperature. This design can not only be an independent intelligent terminal, but also be directly embedded in household appliances to achieve remote intelligent control of household appliances.
With the advantages of low price, easy expansion, stable performance and good interaction, it can vigorously promote the development of Internet of Things smart home.