FECG Acquisition System Integration,Testing Experiments And Extraction Methods

Nowadays there is still no FECG machine actually used by hospitals at home and abroad. The signal processing technique, such as how to separate and extract the FECG, is recognized as the main difficulty. However, in order to study the signal processing algorithm, it is necessary to build a FECG acquisition system to obtain a lot of experimental FECG data. Currently, there is no multi-channel FECG acquisition equipment in homeland. And it is difficult to obtain 8-channel acquisition equipment from other countries. Domestically some people have launched some FECG machines with few channels, but their data structures are not open to the public.Considering the form and principles of the fetal ECG data acquisition devices are not much different from the adults. The existing mature adult ECG machine is digital and provides data interface. In order to build the FECG acquisition system quickly and collect the FECG data from the hospital as soon as possible, this paper adopts the idea which is to use the high-precision standard ECG machine and PC to integrate a multichannel FECG acquisition system. At the same time, the lab self-developed single-channel ECG acquisition system is used as a portable FECG acquisition device.This paper has managed to integrate several FECG acquisition systems and made some comparisons between them. This is the second chapter. Chapter 3 acquires 100 pregnant women’s FECG data with the selected integrative acquisition system and processes the data with the existing lab software. In Chapter 4, there are some investigations on the FECG extraction algorithms and some useful results have been obtained. These three chapters are the core of the entire paper.Features of this paper can be summarized as follows:(1)By comparison between the three multi-channel FECG acquisition integration systems, the integration system based on Nihon Kohden ECG machine is selected. It has more high precision, making sure that we acquire the high quality FECG data from the hospital. (2) 100 pregnant women’s clinical experiments have been done and a lot of valuable FECG data have been acquired. Through a lot of explorations, a primary scheme for the electrode’s placement location and placement process on the abdominal wall has been drawn. The data were fully analyzed and processed, achieving some priori-knowledge for the improvement of the FECG automatic separation algorithm. (3) Based on other previous work, a suitable linear transformation to improve the data signal-to-noise ratio was put forward, and a method extracting FECG based on Least squares fitting of the corresponding points in multi-channel phase space was also proposed. They both have achieved some good results.