Antenna and Package Design for 61- and 122-GHz Radar Sensors in Embedded Wafer-Level Ball Grid Array Technology

This paper suggests the usage of an optimized structure of the embedded wafer-level ball grid array technology for millimeter-wave antennas-in-package. Multiple antenna arrays in a second redistribution layer have been designed, evaluated, and integrated with different transceivers to form very compact sensor packages for 61- and 122-GHz radar applications. The resulting packages contain a complete radar front end while featuring dimensions of $8\,\,\text {mm}\times 8~\text{mm}$ . The packages are easy to assemble and replaceable. Theoretical considerations, numerical results, and measurements have been carried out for the single components. For the verification of the sensor packages, a system demonstrator was developed, and measurements have been performed in continuous-wave mode. At both frequencies, promising system performance regarding range and distance errors could be confirmed without the usage of complex processing and calibration algorithms.