Respiratory rate (RR) is one of the vital signs which is commonly measured by contact-based methods, such as using a breathing belt. Recently, significant research has been conducted related to contactless RR monitoring - however, the majority of experiments are performed in situations when the subject is oriented towards the radar. In this research, we are interested in monitoring the breathing of subjects who can be anywhere in the room. A system of three impulse radio ultrawideband (IR-UWB) radars is used to cover the whole room. A Kinect camera that can track subjects' joints 3D coordinates was employed to localize the subjects. The results of RR monitoring using IR-UWB radars and Kinect camera show good performance in single/multiple subject(s) tracking and RR estimation.