The Calder system was a planetary system. A planet in this system, Calder II, was the location for a Federation science station in the mid-24th century. (TNG: "Gambit, Part I", "Gambit, Part II")
According to Star Trek: Star Charts (p. 45) and Stellar Cartography: The Starfleet Reference Library ("Federation Historical Highlights, 2161-2385"), the Calder system was located in the Beta Quadrant. It was a binary system of a F-class star and an A-class star. This system was a destination on the ancient Debrune trade route.