| In this work we present a comparison between several beam patterns obtained with a conventional SAFT technique, where only one element in emission and other in reception are used, applying different activation sequences of the elements of a two-dimensional array. As we show, different activation sequences produce different beam patterns, demonstrating thus that not only the elements used to emit and receive the signals determine the radiation pattern, but also the sequences in which these elements are activated. Thus, the coarray becomes an essential tool to analyze the radiation pattern generated when synthetic apertures techniques are applied over two-dimensional arrays. |