Small antenna at 5.4 GHz for 11 mm telemetry-unit in harsh environment

The design of a small patch antenna in C-band is presented; it is dedicated to the instrumentation of a 20 mm caliber projectile with a telemetry unit. The antenna diameter is 0.2 λ at 5.4 GHz. This antenna includes some metallized vias through the whole antenna, to be used also as a connector for the onboard electronics. Their presence don’t degrade the radiation properties neither the polarization. This antenna was used in a few firings, endorsing accelerations of 45 000 g and spin rate of 900 Hz. Its survival and its good function during the projectile flight were demonstrated.