Effects of finite aperture and random phase errors for a space debris radar antenna array

Surveillance radar for the detection of space debris are typically based on phased arrays, mainly to increase the modularity and the steering flexibility. However, any inaccuracy in the determination of the radiation pattern, either due to array truncation and/or feeding errors, may result in a wrong detection. For this reason, this paper investigates the effect of the array truncation and of the feeding phase inaccuracy on the preliminary design of an array under development at the European Space Agency. The radiation patterns obtained by considering both the embedded element behavior (i.e., the element inserted in an infinite array) and a more accurate element behavior (i.e., accounting for the edge effects) are compared. Moreover, a Monte Carlo analysis is performed to investigate the effect of phase errors. For both sources of inaccuracy, the nominal radiation pattern is compared with the perturbed one, to assess the possible effects on the radar performance.