  Roadside units (RSUs) can help vehicles sense the traffic environment, so as
to improve traffic safety. Since the sensing capability of single RSU is
limited, we propose a multiple RSUs cooperative radar sensing network
(RSU-CRSN) with signal-level fusion technique. Spatial registration is an
essential prerequisite and foundation for RSU-CRSN with signal-level fusion. In
this paper, we present an adjustable beam enabled spatial registration
algorithm (AB-SRA) that makes the sensing area of each RSU coincide by
adjusting the sensing beam width of RSU. To adjust the width of sensing beam
flexibly, a beamwidth adjustable beamforming algorithm (BABA) is proposed in
this paper. Simulation results show that the performance of AB-SRA is close to
perfect spatial registration.
