Synthesis of Sparse Near-Field Focusing Antenna Arrays With Accurate Control of Focal Distance by Reweighted <i>l</i> <sub>1</sub> Norm Optimization
Zixuan Huang, Yu Jian Cheng, Hai Ning Yang
Abstract
A method based on reweighted l <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><b>1</b></sub> norm regularization for synthesizing a near-field (NF) sparse array with accurate control of 3 dB beamwidth(BW), focal distance, and peaksidelobelevel (PSL) is proposed in this communication. We first formulate the problem of synthesizing NF sparse array as a reweighted l <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><b>1</b></sub> norm optimization problem. The constraints for NF focusing array are proposed to accurately control the 3 dB BW, focal distance, and PSL at the same time. An effective definition of the solution space for the NF synthesis problem is proposed to have the NF pattern well constrained and ensure the practicability and convergence of the proposed method. Finally, simulation examples are presented and compared with full-wave simulation results to validate the effectiveness and advantages of the proposed method.