A compact manufacturable 76-77-GHz radar module for commercial ACC applications

TLDR

The design prioritizes ease of manufacture and cost reduction for commercial millimeter‑wave systems, emphasizing predictive modeling to ensure circuit robustness. The module is fabricated using standard high‑volume assembly techniques on a low‑cost 127‑µm glass substrate, employing discrete GaAs/AlGaAs pHEMTs, Schottky diodes, varactors, and monolithic microwave ICs, with a novel microstrip‑to‑waveguide transition and a quasi‑optical antenna, resulting in a 20 mm × 22 mm × 8 mm transceiver with three waveguide ports and IF output. Measured results confirm that the single‑substrate transceiver module performs adequately for 76‑77‑GHz pulsed‑Doppler radar applications, with component and system‑level performance meeting design expectations.

Abstract

The design and measured results of a single-substrate transceiver module suitable for 76-77-GHz pulsed-Doppler radar applications are presented. Emphasis on ease of manufacture and cost reduction of commercial millimeter-wave systems is employed throughout as a design parameter. The importance of using predictive modeling techniques in understanding the robustness of the circuit design is stressed. Manufacturing techniques that conform to standard high-volume assembly constraints have been used. The packaged transceiver module, including three waveguide ports and intermediate-frequency output, measures 20 mm/spl times/22 mm/spl times/8 mm. The circuit is implemented using discrete GaAs/AlGaAs pseudomorphic high electron mobility transistors (pHEMTs), GaAs Schottky diodes, and varactor diodes, as well as GaAs p-i-n and pHEMT monolithic microwave integrated circuits mounted on a low-cost 127-/spl mu/m-thick glass substrate. A novel microstrip-to-waveguide transition is described to transform the planar microstrip signal into the waveguide launch. The module is integrated with a quasi-optical antenna. The measured performance of both the component parts and the complete radar transceiver module is described.