Transponder Landing System

One airport I frequently use in the northeast has adopted an improvement plan
which includes, along with a slight runway extension, the installation of a
Transponder Landing System. The airport is currently served by a VOR approach
and a GPS approach, but terrain considerations would almost certainly
preclude commissioning of an ILS there.

I am instrument rated, and I had never heard of a TLS approach. It is not
even mentioned in any of my textbooks, going back over the past 20 years. It
is not mentioned in the FAA Instrument Flying Handbook. In my instrument
training we had to be at least basically familiar with types of approaches we
never expect to encounter, like MLS, and describe principles of GCA’s,
ILS-PRM and SDF’s, and of course we had to fly every type of real-world
approach, from NDB up to LPV’s but never have I heard of a TLS.

I do find internet references to the TLS, developed by ANPC Corporation, of
Hood River, OR. Most of these references date from the early 2000’s, but some
are more recent. A Wikipedia article from 2005 treats it as a standard type
of approach, just as if they were talking about an ILS. The same article
however states that WAAS and LAAS have failed to garner widespread
acceptance.

So my question - does this type of approach really exist, other than on
Wikipedia? Can someone point me to an approach plate that says "TLS" on the
top? What would lead a purportedly expert consultant to recommend this type
of approach for installation in a New England airport today?