In 1898 it is claimed that Nikola Tesla built a radio transceiver designed for communication with extraterrestrial intelligence. It has never actually been proven if this is a claim based on reality, delusion or braggarts bravado. In 1899 he claimed to have detected coherent radio signals which he believed came from Mars. See: Tesla on Time Travel
Tesla died at the age of 86 in 1943 and much of his science died with him.
FRB 121102 is in a small galaxy long ago and far away. Far away as in 3 billion light-years away and long ago in that the radio bursts initiated when single celled life forms were just beggnning to evolve here on Earth.
The most titilating notion regarding these Fast Radio Bursts invoves the theory that they are from an advanced intelligence . While that is certainly feasible it is not the only possible explanation.
'It's very funky how the individual bursts can pop up anywhere in this wide range of frequencies, even though each individual burst has a relatively narrow frequency coverage ..... I have yet to see anyone offer up a good explanation for how that might happen.' Peter Williams of Harvard University
Harvard researchers have also speculated that these Fast radio bursters could be beams set up to potentially power light sails of extraterrestrial craft.
Another source of unexplained radio waves from space come from small red star dubbed Ross 128, about 11 light-years from Earth. The signals were detected by researchers at Arecibo Observatory in Puerto Rico led by Abel Mendez. Researchers are fairly certain that the radio waves originate in deep space.
Mendez does not believe the signal originated from extraterrestrial intelligence, but still can't explain it's origins despite multiple theories. The likelihood is that it is from a geostationary satellite.