This paper presents an exploitation of the existing two dimensional radars(2D) which have two identical antennas for reception to be upgraded to a threedimensional radar (3D) in order to measure the height as well as the slant rangeand azimuth direction. The height measurement is important for preliminaryinformation for reducing the time required for acquisition. Software DefinedRadio (SDR) is chosen for the implementation of height finder processor is givenin this paper. Design parameters are selected for the proposed height finderprocessor in order to accommodate SDR requirement. This work is also concernedwith the analysis of the parameters which affect the accuracy of height finding.These parameters include the refraction index, smooth surface reflection,divergence and rough surface reflection. The results of the analysis show thefeasibility of this proposal to upgrade the 2D to 3D radars