This paper presents an investigative study of the ranging capabilities of a miniature tapered-slot UWB antenna and an analysis of the influence of the human body on the accuracy of range estimates. The study involves determining how precisely the point-to-point distance between two identical tapered-slot antennas can be deduced through the signal Time-of-Flight from the transmitting antenna to the receiving antenna. Channel Impulse Response and peak detection techniques have been used for range estimation. Both on-body and free-space scenarios have been considered for this study. Very high accuracy is observed in calculating the range estimates between the two antennas, both when the antennas are in free-space and when placed on the human body.