  In this study, we consider a pulse-Doppler radar relying on a simultaneously
transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) for
scanning a given volume; the radar receiver is collocated with the STAR-RIS and
aims to detect moving targets and estimate their radial velocity in the
presence of clutter. To separate the echoes received from the transmissive and
reflective half-spaces, the STAR-RIS superimposes a different slow-time
modulation on the pulses redirected in each half-space, while the radar
detector employs a decision rule based on a generalized information criterion
(GIC). Two scanning policies are introduced, namely, simultaneous and
sequential scanning, with different tradeoffs in terms of radial velocity
estimation accuracy and complexity of the radar detector.
