© 2020 URSI.In this paper, design and implementation of a compact, low-profile and low-cost altimeter antenna is presented. A top-open dielectric waveguide is utilized to obtain a radiation pattern that illuminates from 20 to 70 degrees on the elevation plane. The proposed antenna pair can be used efficiently as a radar altimeter antenna in the course of landing. The antenna can cope with high skin temperatures, especially in supersonic flights because a high-temperature resistant dielectric material is used. Satisfactory results are obtained from EM simulations and antenna measurements.