Compact and high-performance 76 GHz millimeter-wave radar front-end module for autonomous unmanned helicopters

This paper examines the development of a 76 GHz millimeter-wave radar front-end module, which can be equipped with small autonomous unmanned helicopters. The key feature of the module is a broadband RF signal transmission, which is compact and lightweight while using commercially available MMICs and materials. Firstly, the performance of the module is examined by experimental results. The 4-cm range resolution is achieved by 6 GHz RF signal bandwidth. To improve conversion loss and frequency flatness at a waveguide to microstrip line transition, a new simple design structure is analyzed and measured. The transition achieves less than 1.2-dB conversion loss. Finally, the compact RF module with the transition is designed and measured. The volume and weight are 0.99 cm³ and 7 g, respectively.