In this paper, we propose an efficient two-dimensional geo-location estimation system for mobile social security robots, where the location is obtained by direction of arrival (DOA) and time of arrival (TOA) of the radio signal. The proposed system requires only one reference signal while the conventional systems generally demand more than three reference signals. For estimating TOA and DOA information simultaneously, we employ a two-dimensional multiple signal classification (2-D MUSIC) algorithm. In addition, the performance analysis of proposed system is provided in terms of location accuracy and computational complexity by comparing it with two-dimensional Matrix Pencil (2-D MP) algorithm. The simulation results show that the proposed geo-location estimation system achieves the positioning accuracy within 3 meters in 2 kilo-meters coverage which is usable for mobile robots.