Last year Möchel spotted a similar listening post operated by the US intelligence service NSA, located not far from the UN headquarters, The Local reported.
Möchel believes that the US Embassy in Vienna and a villa in Pötzleinsdorf are listening stations too.
One of the wealth of documents leaked by former NSA contractor Edward Snowden offers a clue to how such listening stations work.
Möchel said that if the four listening stations work together, monitoring mobile phones would not be a problem.
The British embassy has so far declined to comment on the allegations.
Last week the Austrian government complained about an unnamed party engaged in "secret intelligence to the detriment of Austria."