Adjustable Parameters Online Digital Filter Based On STM32

Filter is mainly used in image processing,digital communication spect rum pattern recognition and automatic control,etc.Digital filter shares more and m ore market because of its stable filter performance,frequency response speed,high precision and high level of integration.For many users of adjustable parameters Wireless non-contact demand such as low cost,this paper proposes a parameter variable digital filter based on STM32.The main content of the filter is made up by STM32 module and Lab VIEW.STM32 module part: FIR digital filter designes and researches in STM32 environment.Mainly designes filter formula and sampling frequency,using the filter formula and filter coefficient for FIR filtering and output,after the STM32 data acquisition.Parameters of sampling frequency can be configured and filtered.In addition,Drawing STM32F407 board circuit schematics and PCB diagram,welding circuit board and debugging program.The second part is the Lab VIEW part: configurates the filter coefficient and communicate with the WIFI module wirelessly during the Lab VIEW environment.The main content is that configurates filter coefficient array by Lab VIEW software to determine the type of filter and sampling frequency.And use TCP/IP protocol communicates with WIFI module wirelessly,the filter coefficient is transmitted to the STM32 module.TO achieve wireless non-contact online configurate for filtering coefficient.In addition,the filtering coefficients of different filter types with different sampling frequencies are generated by MATLAB platform configuration.The research process of the system was divided into three steps: firstly drawing PCB,designe the filter algorithm and make a basic filter on the hardware platform of STM32;secondly,send filter coefficients from PC serial port to STM32 with the serial communication software,to ensure the filtering coefficient not only can change but also can read and write;lastly,communicate with the WIFI module by using Lab VIEW software platform to realize of wireless non-contact,online configuration of filter coefficients.This paper first introduces the main contents and the research significance of variable parameters of STM32 digital filter and make a detailed design scheme,and then design of the hardware and software design of the variable parameters of STM32 digital filter,lastly combining the hardware and software function test.Finally,a variable parameter digital filter with parameter adjustable,wireless contactless and low-cost STM32 is realized.