The detection and discrimination of quantum states serve a crucial role in
quantum signal processing, a discipline that studies methods and techniques to
process signals that obey the quantum mechanics frameworks. However, just like
classical detection, evasive behaviors also exist in quantum detection. In this
paper, we formulate an adversarial quantum detection scenario where the
detector is passive and does not know the quantum states have been distorted by
an attacker. We compare the performance of a passive detector with the one of a
non-adversarial detector to demonstrate how evasive behaviors can undermine the
performance of quantum detection. We use a case study of target detection with
quantum radars to corroborate our analytical results