Operation of Rigid-Flex 3-D Printed Microwave Antennas for UWB Radar Under Thermal and Vibration Stress Conditions

We present the application of novel additively manufactured hybrid rigid-flex Vivaldi antennas as transmit and receive elements for an ultra-wideband (UWB) frequency modulated continuous wave (FM-CW) radar. This paper focuses on a series of measurements performed at Ku-band (12–18 GHz) to assess the effectiveness of these 3- D printed antennas within the radar loop, under thermal and vibration stresses. First, we verified the antennas' satisfactory operation down to -32 °C and inferred that thermal cycling would have minimal effect on the impulse response of the radar system. Next, we investigated the effects and bounds of vibration stress that could be sustained by these antennas and offer recommendations to support even higher vibration levels in future design iterations. Additionally, we present a succinct overview of the antenna design and the experimental setup used to perform these measurements.