An Efficient Multibeam Testing Method for Phased Arrays With Improved Accuracy in Sidelobes

Phased arrays play a crucial role in various communication and sensing systems. However, the excessive number of beams makes traditional multibeam measurements time-consuming. To address this problem, researchers developed a method that acquires element patterns via sparse sampling and conventional interpolation with all elements activated, from which the array pattern is derived. A limitation of this method is that while the main beam is accurately reconstructed, the conventional interpolation process yields significant inaccuracies, particularly in the sidelobes and the position of the first nulls. In order to tackle this problem, this letter introduces a compressed sensing-based interpolation algorithm in the reconstruction of element patterns with sparse samples. The proposed interpolation method is validated by the FEKO simulation software. When the beam is directed along the broadside, the errors in the sidelobe position and gain obtained at cut using the conventional spline interpolation method are 4° and 2.13 dB, respectively. However, the beam obtained using the proposed interpolation method in this letter exhibits no error at the sidelobe position, and the error at the sidelobe gain is only 0.02 dB. The accuracy in sidelobe testing of the array pattern is also validated by the experimental data. Both simulation and experimental results verify the feasibility of the proposed method.