This article is from the Star Trek Tech FAQ, by Joshua Bell inexorabletash@hotmail.com with numerous contributions by others.
In "Data's Day" [TNG], the use of a subspace carrier wave was
mentioned as the method by which the transporter beam propagates.
In "Bloodlines" [TNG], Bok has a subspace transporter, a technology
which was researched but later abandoned by the Federation. The range
is at least 300 billion kilometers, and at most several light years
and the subject is put into a state of molecular flux. Doesn't sound
healthy. How is this different than normal transport? Probably just a
deeper level of subspace.
In "The High Ground" [TNG], transporting through folded space using a
subspace field coil made for instant, untraceable transports. The only
problem is that it causes slow, irreversible genetic damage to the
transport subject. It is a cumulative effect: one or two transports
would be harmless, but dozens or hundreds are fatal. The Federation
experimented with such technology in the 23rd Century, so this may be
what Bok was using as well. (Joseph M. Osborne)
 
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