REDUKSI DERAU DENGAN MENGGUNAKAN TRANSFORMASI WAVELET PADA DATA HEMBUSAN MERAPI DI STASIUN KALIURANG; WAVELET DENOISING OF MERAPI PHREATIC ERUPTION DATA FROM KALIURANG STATION

Al Wardah, Siti Robiah Ummu Karomah, Wiwit Suryanto

2015 | Skripsi | FMIPA

In this research, wavelet denoising has been done to enhance signal to noise ratio of Merapi phreatic eruption data from Kaliurang station. The wavelet denoising process consists of creating synthetic seismogram and adding noise from 10% to 100% to it. After that we perform wavelet decomposition to the seismogram in order to obtain the most suitable wavelet parameters. These parameters are then applied to merapi phreatic data that is recorded in Kaliurang station. As the result, denoising the data using Coiflet wavelet obtains the most suitable parameters, with correlation value 0.99 and 5% uncertainty. Signal to noise ratio of Merapi phreatic eruption in Kaliurang station before wavelet denoising is 6.53 dB and 55.97 dB after applying denoising process. This result shows that wavelet denoising significantly increases signal to noise ratio in this station.

Kata Kunci : Coiflet; denoising; signal analysis; phreatic eruption, wavelet