The birth name of The Signal is Duke Thomas.He was introduced as a preteen boy rescued by Batman in Batman #21 of the new 52.He was created by Scott Snyder and Greg Capullo.

According to Comic Vine During the events of Zero Year, Duke Thomas' family found and took care of a knocked out Bruce Wayne. In the Riddler-controlled Gotham City, the only way to return things back to the way they were was to stump the city's new ruler with a riddle, so Duke spent his days solving riddles and attempting to concoct the perfect one that would save the city.

During the events of Endgame, Duke Thomas is now a teenager, and he and his parents are forced to take part in the Joker's recreation of the murder of Thomas and Martha Wayne.

In the search for his parents, Duke crosses paths with a group of teen vigilantes calling themselves Robins, and fights crime alongside them as their de facto leader, taking orders and supplies from a man they only know as The Nest.

             Duke would later join the vigilante team of Robins, but the team is soon outlawed by the Gotham City authorities after the death of a police officer partly blamed on the Robins' activities.They were pursued by Batman who was sent after them.After the the end of the Robins adventure Duke was given the name The Signal by strangely enough The Joker.Now The Signal patrols Gotham by day.You should check out Batman and The Signal.