The .5" Cavity Backed Archimedean Spiral Antennas from Meggitt PLC is a Antenna with Frequency 18 to 50 GHz, Gain -1 to 4 dBi, Operating Temperature -55 to 85 Degree C. Tags: Spiral. More details for .5" Cavity Backed Archimedean Spiral Antennas can be seen below.