Implementation of digital signal processing algorithms in biomedical electronics devices on the XILINX FPGA

Abstract

The process of creating fully digital biomedical diagnostic devices involves deep knowledge in both digital electronics and digital biomedical signals processing [1-3]. The purpose of this paper is development of the engineering approach of hardware implementation of basic digital signal processing algorithms (DSP) applied in biomedical electronic devices based on programmable logic integrated circuits. The processes of hardware implementation of the basic algorithms for digital signal processing (DSP) can be divided into three main steps. At the first step, the amplitude values of the samples of discrete pulse characteristics of the low-pass filter and the Hilbert filter are calculated in the FDATool application of the Matlab. At the next step, the Simulink application performs simulation modeling based on the results of the first step, and at the hardware implementation step, the field programmable gate array Xilinx Spartan 6 is used to simulate DSP circuits in the Xilinx ISE design system, as well as directly measured measurements. The amplitude-modulated oscillations demodulator was chosen as an example of the full-scale implementation of basic DSP algorithms in biomedical devices. Experimental measurements were made of the nonlinear distortion coefficient of the detected (informational) signal for three variants of amplitude modulation demodulators: full-wave, using the square root function and synchronous with phase locked loop . During the experimental study, an optimal modulation factor of 60% was chosen from the point of view of energy efficiency. As the results of simulation and experimental studies show, the synchronous demodulator has turned out to be the best option.The obtained results of the experiment and simulation have confirmed the practical applicability of the proposed embodiment in DSP for use in biomedical electronic devices.