The Ilecom system was an inhabited star system located in Federation space. This system was in the Alpha Quadrant.
In 2364 the Ilecom system reported that the Manheim Effect had been observed even though they were several thousand light years from the Vandor system where the effect originated. (TNG: "We'll Always Have Paris")
The Ilecom system appeared in the starchart Data and Picard were studying in Stellar Cartography in 2371. (Star Trek Generations, display graphic)
The star chart seen in "Generations" depicted the location of planets, stars, and star systems in the Alpha Quadrant. Based on the dimensions of the circles used to mark locations on the star chart seen in "Generations", this system was located relatively far to the USS Enterprise-D.