Tidal Time Series Analysis in R

I am looking at using R to analyze time series data containing a tidal 
component.  I need to remove the tidal signal to extract the time 
series of the phenomena I seek to study.  A browse of R-project search 
engines has not been too fruitful?  I've found 'hoa' and 'Rwave', but 
need further help getting started.  THANKS.

-wa