ECG Sinyallerinde Gürültü Gidermek için Dalgacık Dönüşümünün FPGA Tabanlı Donanımsal Gerçeklemesi

Bu makalede, biyomedikal sinyal olan ECG sinyallerinde gürültü gidermek için dalgacık dönüşümü (DD)yöntemi ve donanımsal gerçeklemesi sunulmuştur. DDü ile gürültülü sinyal seviyelere ayrıştırılarak gürültülübileşenler eşikleme işlemine tabi tutulmuştur. Eşikleme yöntemlerinden biri olan yumuşak eşikleme kullanılarakgürültülü katsayılar sıfıra çekilmiştir. Eşikleme sonucunda elde kalan katsayılar tekrar birleştirilerek sinyalgürültüden arındırılmıştır. Gürültü giderim algoritmasının hem donanımsal hem de yazılımsal olarak kolay veesnek bir şekilde tasarlanıp değiştirilebilme ve programlanabilme özelliğini taşıması için FPGA (FieldProgrammable Gate Array Alan Programlanabilir Kapı Dizileri) tercih edilmiştir. Bu çalışmada, Xilinx serisiFPGA platformu kullanılmıştır.

FPGA Implementation of Wavelet Transform for Denoising ECG Signals

In this paper, wavelet transform (WT) method and hardware implementation are presented to resolve the noise inthe ECG signals, which is biomedical signals. The noisy signal is seperated with DD, the noisy components aresubjected to the thresholding process. The noisy coefficients are set to zero by using soft thresholding, which is athresholding techniques. The signal is eliminated from the noise by recombining the rest of coefficient obtainedfrom the thresholding. The FPGA (Field Programmable Gate Array) is preferred to have changeable andprogrammable features and to characterize the noise removal algorithm with both easy and flexible hardware andsoftware designed. In this study, the Xilinx FPGAs series platform is used.

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