A 79-GHz LTCC radar frontend using a nonuniform array with non-identical elements

This paper presents a 79-GHz radar sensor in LTCC technology. A multiple-input multiple-output method combined with a non-uniform array was used to enlarge the virtual aperture and to achieve a wide field of view (FoV). Due to the high loss of the LTCC material, non-identical array elements were introduced to compensate the additional loss in the feeding path. After optimization of the weighting factors, a FoV of 80° has been achieved. The total size of the LTCC RF-frontend is 23mm × 23 mm. The measured effective isotropic radiated power of the sensor is ≤ 14 dBm at 79 GHz. The minimal angle resolution is ≤ 9°. The noise figure of the radar sensor is around 19.5 dB.