International Journal of Science and Research (IJSR)

International Journal of Science and Research (IJSR)
Call for Papers | Fully Refereed | Open Access | Double Blind Peer Reviewed

ISSN: 2319-7064


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Research Paper | Physical Science | India | Volume 13 Issue 5, May 2024 | Rating: 4.6 / 10


Spectral Analysis of Air Quality Index Using Haar Wavelet Transforms

Asad Ali Khan | Anil Kumar [141]


Abstract: Ambient air pollution is one of the big problems of today in perspective of environment and health degradation. The air quality of any place is measured in terms of the air quality index (AQI). The AQI of any place is decided by the highest value of one of the air pollutants out of the Particulate matter, Nitrogen dioxide, Ammonia, Sulphur Dioxide, Carbon Monoxide and Ozone of that place. Wavelet transform has become an important tool in the non-stationary and transient data/signal processing due to its time-frequency localization property. In wavelet transform as the scale increases, the resolution decreases, and a better estimate of the unknown trend of the data is obtained. We have selected Anand Vihar, Delhi, India as our study area and its daily average AQI data for one year before first lockdown (from March 25, 2019 to March 24, 2020) and during lockdown (March 25, 2020 to June 08, 2020) is taken as the raw data. The spectral analysis of this AQI data is performed by using Haar wavelet, level-7 with help of MATLAB wavelet toolbox. The highest scale approximation i.e. trend of data and histogram of the data are shown and discussed. Some statistical parameter like average, kurtosis, skewness and standard deviation are also determined and discussed.


Keywords: AQI, approximation, detail, Haar, trend


Edition: Volume 13 Issue 5, May 2024,


Pages: 77 - 80


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