The introduction should be clearer, and even though the home page links
directly to two main introductory papers on Dr. Edmondson's research,
that does not always mean that people are going to go there and read
them.

The idea is that on a galactic scale we need something to get the attention
of ETI if we want to have them signal us (assuming they have the ability and
want to signal us or anyone else in the first place).

Earth is far too small and dim to be noticed directly even in a nearby system.
The Sun becomes an average looking star within a few dozen light years.
And our electromagnetic transmissions only reach about 100 light years in
radius, a mere fraction of the 100,000 light year wide Milky Way galaxy.
Plus with 400 billion stars to choose from, why choose us?

The only common events that could attract both humanity and ETI astronomically
are supernovae and pulsars. The idea, which has already been suggested for
supernovae, is to aim signals in the direction 180 degrees or so opposite a pulsar
or SN at star systems which could be habitable. The hope is that technological
ETI would also be into astronomy and observing such phenomena just as we do.
As we have their attention (or they us), the artifical signals could come streaming
in from the same direction, get their notice, and hopefully a response.

This is what Dr. Edmondson has been studying with the Arecibo radio telescope.