ERTAN PEKŞEN, Fatih SEVİM

Hiperbolik Sekant Fonksiyonlar ile Analitik Çentik Süzgeç Tasarımı

Hiperbolik sekant fonksiyonlar ile çentik süzgeç tasarlanabilir. Bu çalışmada zaman ve frekans ortamlarında çentik süzgeçler incelenmektedir. Genel olarak, çentik süzgeç tasarımının amacı ölçülen verilerden istenmeyen (genellikle 50 veya 60 Hz lik girişimler) kısımların süzülmesidir. Bu çalışmada zaman ortamındaki çentik süzgeç fonksiyonu, çentik süzgeç fonksiyonunun frekans ortamındaki ifadesinden türetilmiştir. Basamaklı çentik süzgeci de analitik olarak tasarlanmıştır. Sayısal örneklerde çentik ve basamaklı çentik süzgeçler zaman ve frekans ortamında dikkate alınmıştır. Önerilen çentik süzgecin birim dürtü ve frekans tepki bağıntıları türetilmiştir. Son olarak, yeni tasarlanan filtre başarılı bir şekilde arazi verisine uygulanmıştır.

Analytic Notch Filter Design Using the Hyperbolic Secant Function

A notch filter can be analytically designed by using the hyperbolic secant function. This paper investigates notch filters in both time and frequency domains. Generally, the purpose of a notch filter design is to filter some unwanted signal (usually interference at 50 or 60 Hz) from observed data. In this study, the impulse response of a notch filter in the time domain was obtained by using its frequency domain expression. A cascaded-notch filter was analytically designed as well. Numerical examples were considered for a single notch filter and a cascaded-notch filter in the time and frequency domain. The frequency response and the impulse response of proposed notch filter were derived. Finally, the new designed filter was successfully applied to a field data set.

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