A Hardware and Mobile-Health Based System for the Analysis of EEG Signals

Abstract

Instantaneous monitoring of EEG signals is very important for patient follow up. Independent follow-up systems are needed for the physician to monitor and diagnose the patient continuously. In this article, a real-time design for an FIR (Finite Impulse Response) filter was presented using a cosh window function implemented on an FPGA (Field Programmable Gate Array) environment. The reason for using the cosh window is that it has better ripple ratio and larger sidelobe roll-off ratio than other windows in literature.  Since cosh window parameters can be changed in the developed design, they can be easily adapted to the new state change. After filtering the raw EEG signals, they were converted into a form that could be interpreted by a specialist physician. The filtered data was uploaded to a server on the internet so that the physician could access the EEG signals remotely via a mobile phone. The proposed system facilitated examination of the patient by the physician and made it possible to help instantly diagnose any illness.

Keywords

• FPGA,FIR filter,cosh window,EEG,android application

EEG Sinyallerinin Analizi için Donanım ve Mobil-Sağlık Tabanlı Bir Sistem

Öz

EEG sinyallerinin anlık olarak izlenmesi hasta takibi açısından son derece önemlidir. Hekimin hastayı sürekli olarak izlemesi ve teşhis yapabilmesi için mekândan bağımsız takip sistemlerine ihtiyaç vardır. Bu makalede, FPGA ortamında cosh pencere fonksiyonu kullanılarak FIR (Finite Impulse Response) filtrenin gerçek zamanlı tasarımı sunulmuştur.  Alınan ham EEG sinyalleri filtrelendikten sonra bu sinyaller uzman hekim tarafından yorumlayabilecek şekle dönüştürülmüştür. Filtrelenmiş veriler internet üzerindeki servera aktarılmış böylece, hekimin uzaktan mobil telefon yardımıyla EEG sinyallerine ulaşması sağlanmıştır. Önerilen bu sistem sayesinde hekimin hastayı sorgulaması kolaylaşmış ve anlık olarak hastalık teşhisi yapabilmesine imkân sunulmuştur.

Anahtar Kelimeler

• FPGA,FIR filtre,cosh penceresi,EEG,Android Uygulaması

Kaynakça

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