The application of ground penetrating radar (GPR) for pavement evaluation is relatively new concept in India, especially for transportation infrastructure study to evaluate its defects and condition rapidly, continuously and non-destructively. The images of the studied pavement section containing underground utility (here metallic water pipes & electric cables are taken) items show hyperbolic signatures and by using velocity calibration by hyperbolic matching approach it is possible to determine the depth and leakage status. But, generally the main problem that is encountered in the analysis of the GPR image is the occurrence of false hyperbolic signatures which may appear due to the reflection from nearby big trees, houses and overhead bridges/ under ways.  It is therefore, important to resolve the issue of detection of false target in air by GPR. Thus, in the present work practical data have been acquired using 250 MHz ground coupled GPR from the areas having big objects that can interfere with the GPR images. The GPR signatures of the trees, fly over and overhead pathway have been collected, and based on the GPR acquired velocity (from GPR image) of the electromagnetic (EM) wave propagating through the ground has been analyzed to differentiate between the air objects and the ground objects. After analysis it has been found that if the GPR extracted velocity is within the range of (0.050 m/ns to 0.150 m/ns), it represents all sorts of ground materials (generally used for construction) under various moisture conditions (presence of huge water to dry condition), and the object is under the earth surface. Whereas, if the velocity is above 0.19 m/ns or 0.200 m/ns and above represents false air events i.e. object is in air. This work can provide technical assistance to the beginners involved in the GPR based manpower development programmes.