Although phased arrays have been around for long time, almost half a century, many digital signal processing techniques were not possible to consider in practical systems until recently. These developments have been fuelled not only by new computation capabilities but also by the huge interest of phased arrays in civil applications such as Massive MIMO, automotive radar and UAV’s navigation. Motivated by the recent advances in hardware for antenna arrays and computational platforms, in this tutorial, we present a digital signal processing perspective of phased arrays as well as a gentle introduction to algorithms for direction-of-arrival (DoA) estimation and digital beamforming.
Differently from hardware-oriented tutorials, in this tutorial we first delve into the modelling of phased arrays from the signal processing perspective, providing the required background to follow advanced array processing algorithms and literature. Then, we present the foundations of classical beamforming and DoA estimation methods that have been successfully employed across differently applications in the last years. Also, we will discuss modern techniques for array processing, beyond classical subspaced-based techniques, e.g., MUSIC, ESPRIT, etc., leveraging optimization theory and sparse signal processing for both regular and sparse phased arrays. Finally, highlights of current developments in phased array signal processing algorithms and future research trends in communications and imaging systems will be presented.