Embodiments herein provide a test apparatus and system for a millimeter wave reflection test to measure propagation of millimeter wave signal through a material at various incident angles. In one example, the test apparatus may include a mechanized arch over a base plate, the mechanized arch including antenna carriers coupled to the mechanized arch and configured to hold respective antennas. A motor assembly moves the antenna carriers along the mechanized arch while maintaining the antenna carriers at symmetrical (equal and opposite) angles with respect to the base plate.