Küresel Konumlama Uydu Sistemleri Tabanlı Deprem Gözlemlerinin Duyarlığı

Abstract

Bu çalışmada, sarsma tablası üzerinde farklı depremler için ivmeölçer ve Küresel Konumlama Uydu Sistemleri (KKUS) gözlemleri yapılmış ve gözlemler ile gerçek girdi arasındaki farklar zaman ve frekans ortamında incelenmiştir. Ölçülen KKUS yer değiştirme dalga formları ve ivme kayıtlarından elde edilen dalga formları gerçek girdi ile karşılaştırıldığında KKUS’un Karekök Ortalama (RMS) hata değerleri 4-9 mm arasında değişirken, ivme kayıtlarından elde edilen yer değiştirme dalga formlarının RMS değerleri 1-110 mm arasında değişmektedir. KKUS yer değiştirme dalga formlarının ortalama RMS değerleri ~6 mm civarındadır. Yapılan sinyal tutarlık analizlerinde, ivme kayıtları ile gerçek girdi sinyali arasındaki tutarlığın 2-3 Hz’den daha yüksek frekanslarda gözlendiği, düşük frekanslarda tutarlığın düşük olduğu buna karşın KKUS ile gerçek girdi sinyali arasındaki tutarlığın 1 Hz’e kadar olan düşük frekanslarda düz olduğu gözlenmektedir.

Keywords

• KKUS,İvmeölçer,Yer değiştirme,RMS hata,Sinyal tutarlık analizi

Precision of Global Navigation Satellite Systems Based Earthquake Observations

Abstract

In this study, accelerometer and GNSS observations were carried out for different earthquakes on the shake table and the differences between the observations and the actual input were examined in both time and frequency domains. When the waveforms obtained from the measured GNSS and acceleration displacement waveforms are compared with the actual input, the Root Mean Square (RMS) error values of GNSS vary between 4 and 9 mm while the RMS values of the displacement waveforms obtained from the acceleration records vary between 1 and 110 mm. Besides, the average RMS values of the GNSS displacement waveforms are around ~6 mm. In the signal coherence analysis, the coherence between the acceleration measurements and the actual input signal is observed only at frequencies higher than 2-3 Hz verifying that the coherence at lower frequencies is low for accelerometers whereas the coherence between GNSS and the actual input signal is observed to be flat at low frequencies up to 1 Hz. 

Keywords

• GNSS,Acceleration,Displacement,RMS error,Signal coherence analysis

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