Yes, you do need a receiver. You have a choice: you can get a freestanding 5132 receiver or an RFK keypad that has a receiver built in. The combo is useful if you think you'd like another keypad; if not, the separate 5132 gives you more flexibility in placement, and it's less expensive.
In either case, the unit simply connects to the keybus, just like any keypad (Red Black Yellow Green). When you're ready, there's an FAQ entitled "Programming DSC Wireless”
that may help.
P.S. Just thought of something........ if you bought the 1616 as a kit, check to see if you already have an RFK keypad before buying a receiver. Some of the kits include an RFK5501.