Abstract: A modular RCS (Radar Cross Section) and IR (Infra-Red) signal generation device includes: a plastic bag which is normally stored in a folded state, and inflated when gas is introduced into the bag as desired; a radar reflector received in the plastic bag, the radar reflector being configured in a multi-hedral reflector structure having a reflection characteristic similar to that of a naval vessel to be protected; hot air tubes formed through the plastic bag, hot air being capable of generating IR signals by flowing through the hot air tubes; and connection patches positioned on one of the surfaces of the plastic bag at the points where the ends of the hot air tubes intersect with the surfaces, respectively, the connection patches being adapted to be attached to those of adjacent modular RCS and IR signal generation devices, respectively, so as to interconnect the hot air tubes with those of the adjacent modular RCS and IR signal generation devices.