The ever-increasing threat of terrorist attacks means screening technologies that are more advanced than common metal detectors are required at security checkpoints. Current imaging systems – working in the millimeter wave (mmW) range – have been proven to offer good results in the detection of metallic and non-metallic threats (e.g., explosives, ceramic knives, or self-made bomb precursors). During the screening process for these systems, however, passengers (i.e., at airports) must adopt a specific position and posture, or they must move in a specific way in front of the scanner. Furthermore, it is desirable for future screening systems to simultaneously offer a higher throughput and detection performance.