In the low-latitude ionosphere, the equatorial plasma bubble (EPB) irregularities and traveling ionospheric disturbances (TID) are two important space weather phenomena. These disturbances can affect radio wave propagation, disrupting satellite communications and navigation positioning systems. Due to the limitations of ground-based detection techniques, substantial observational gaps remain regarding ionospheric TIDs and irregularities over low-latitude oceanic regions. This study introduces an over-the-horizon detection method for low-latitude ionospheric disturbances using the Low-lAtitude long Range Ionospheric raDar (LARID) located in Hainan, China. By resolving the elevation angle of arrival based on the phase difference between the radar's main array and interferometer array, LARID can determine the spatial location of ionospheric disturbances. Leveraging its multi-beam observation capability, we have achieved two-dimensional imaging of TID structures and retrieved their wavelengths and propagation directions. The localization results for EPBs show good agreement with S4 index data from GNSS receivers. Significant differences exist between the observed TIDs and GNSS TEC measurements, which may be partly attributed to the filtering effect of daytime westward wind fields on atmospheric gravity waves. While LARID is currently only capable of observing quasi-east/west propagating TIDs and ionospheric irregularities along the east-west direction, this study finally proposes a method to extend its observational azimuth to full 360° coverage. Ray-tracing experiments demonstrate that this expansion can effectively enhance LARID's detection coverage for background ionospheric disturbances and irregularities.
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