Grating Lobe Suppression for Distributed Phased Array via Accumulated Array Pattern Synthesis

Long-sparse distributed phased array is a promising technique for increasing resolution and reducing expense. However, inherent grating lobes (GLs) caused by large internode distance are hard to suppress, especially for the limited available nodes case. To solve this problem, a novel accumulated array pattern synthesis (AAPS) scheme to suppress the GLs is proposed, utilizing the time-varying node motion to fill the spatial domain sampling. Furthermore, the high sidelobe level problems caused by mismatching between the actual and nominal position of moving nodes due to imperfect motion control are also considered. Hence, under the AAPS scheme, a measurement-based matching algorithm is supplementally proposed based on measuring the relative position and angle between nodes. Simulations are provided to validate the effectiveness of the proposed algorithm.