Dominant Wave Height Estimation Based on Spectral Analysis for Coastal Erosion Monitoring Systems in Real Time

Coastal erosion is becoming a public concern. Deploying low-crested breakwaters is a solution to mitigate its effect in some prone areas. Various proposals for breakwater structures, both fixed and flexible components, have recently been proposed. The efficacy of some well-known structures can be determined based on the forms themselves. Evaluating the performance of the flexible breakwater is more challenging. The breakwater's effectiveness can be assessed based on its ability to decrease wave height and energy. Therefore, estimating the wave height is essential. This study aims to develop a sensor node that monitors the water surface level in real-time or near-real-time and to estimate the wave height from the time series data obtained from the sensor node. The proposed method estimates the wave height by analyzing the spectrum of a time series. It was tested through a field experiment on a beach in Prachuapkhirikhan Province. The experimental results show that the proposed method can estimate the dominant wave heights with a mean absolute error of 0.45 cm and a satisfactory correlation coefficient of 0.83. These findings have significant practical implications for real-time coastal erosion monitoring and offer a method used in flexible breakwater evaluation.