Obtaining the data of cycle analog signal by using software sampling method, and performing numerical operation to process signal by using a certain calculation method, is a method commonly used of digital signal processing. However, the sampling algorithm is not quite ideal, which restricts the accuracy of digital signal processing. The ideal sampling method is uniform synchronous sampling, but in actual sampling, because of the impact of the timer resolution, there is a truncation error between actual sampling interval and theoretical sampling interval. This thesis details the characteristics of three synchronous sampling methods of the periodic signal and its existing problems in the application, including double rates synchronous sampling method, the deviation cumulative incremental method and parameters of self-optimizing equal interval synchronous sampling method, and analyzes the advantages and disadvantages of various sampling methods. The thesis also details on how to improve the accuracy of periodic signal analysis algorithms through software synchronous sampling methods. At the same time, the thesis analyzes the error of periodic signals synchronous sampling and the frequency domain characteristics of the software synchronous sampling methods. In addition, the thesis further explores the software synchronous sampling methods, introduces a way of using lower sampling frequency for high frequency periodic signal, which can receive the same result of high-frequency sampling through using far less than the frequency of the sampled signal.
Keywords software synchronization; double rates; deviation cumulative; parameters of self-optimizing