The implication of Scripture is that we will know our loved ones in heaven both before and after resurrection. The disciples were able to recognize the Lord after His death and resurrection, though sometimes they did not recognize Him, as with the two disciples on the road to Emmaus. The ability to disguise Himself seemed to be a phenomenon of his glorified body (Luke 24). Normally, however, they were able to recognize Him. Scripture teaches us that we will have a glorified body like his (Phil. 3:21f) which suggests that what was true of His body will be true of ours.
Further, 1 Thessalonians 4:13-18 was written to believers, some of whom had lost a believing loved one. They were concerned about how death would affect those believing loved ones who had died before the Lord returned in person. In Paul’s answer to this he gave revelation that concerned several things: the rapture of living saints and the resurrection of believers who had died, but he also speaks of a reunion not only with the Lord, but with all believers. As a word of comfort this certainly speaks not only of the facts of the rapture and resurrection, but also of a reunion which would mean little if we could not recognize our friends and loved ones.
Also, when Christ was transfigured on the Mt of Transfiguration, the three disciples that were there were able to recognize Elijah and Moses (Mark 9:4-5). How, we are not told, but the fact they were identified suggests we will be able to recognize not only those we have known personally, but saints from all ages.
Finally, the story of Lazarus and the rich man in Luke 16 suggests the same thing is true even now for those in heaven.