Many research institutes and universities have contributed their efforts on developing the multi-purposed unmanned aerial vehicles (UAV) for use either in military or civil applications in past few decades. This is simply because UAV can carry out such missions that may be dangerous, long-endurance, or even reducing the cost and manpower. This paper then emphasizes on the development of a navigation payload system employing the differential Global Positioning System (DGPS) incorporated with an Inertial Measurement Unit (IMU) onboard a home-made UAV. The Radio Data System (RDS) is used as well for conducting the real-time differential correction of the GPS through radio broadcasting in an on-board computer. Therefore, the navigation payload system in combining GPS/RDS/IMU with a digital CCD camera system can provide the UAV with full capability for conducting the data/image targeting acquisition with high accurate positioning and navigation information. The position accuracy with the RDS is augmented to be less than 3 m in the kinematic horizontal flight condition.