The effect of filtering on the determination of lunar tides

The determination of lunar tides obtained by combination of a filtering process and the fixed lunar age technique is proposed. It is shown that such a method allows a reduction of the signal-to-noise ratio without altering the amplitude and the phase angle of the signal. It consequently allows the significant determination of the lunar semidiurnal component M2 from the series of data shorter than those required by other methods and the deduction of other interesting lunisolar components which have not previously been significantly determined in surface pressure and temperature data. The analysis of the data for Gan, Vesuvian Observatory and the Eiffel Tower have provided new determinations of L2(p) and have allowed comparison between the results obtained by the present and other methods.