@inproceedings{6347d22db1a44b2caf9ebbe4567294dd,
title = "Stacked Intelligent Metasurface Performs a 2D DFT in the Wave Domain for DOA Estimation",
abstract = "Staked intelligent metasurface (SIM) based techniques are developed to perform two-dimensional (2D) direction-of-arrival (DOA) estimation. In contrast to conventional designs, an advanced SIM in front of a receiver array automatically performs the 2D discrete Fourier transform (DFT) as the incident waves propagate through it. To arrange for the SIM to carry out this task, we design a gradient descent algorithm for iteratively updating the phase shift of each meta-atom in the SIM to minimize the fitting error between the SIM's response and the 2D DFT matrix. To further improve the DOA estimation accuracy, we configure the phase shifts in the input layer of the SIM to generate a set of 2D DFT matrices having orthogonal spatial frequency bins. Extensive numerical simulations verify the capability of a well-trained SIM to perform the 2D DFT. Specifically, it is demonstrated that a SIM having an optical computational speed achieves an MSE of 10-4 in 2D DOA estimation.",
keywords = "direction-of-arrival (DOA) estimation, reconfigurable intelligent surface, Stacked intelligent metasurface (SIM), wave-based computing",
author = "Jiancheng An and Chau Yuen and Guan, \{Yong Liang\} and \{Di Renzo\}, Marco and Merouane Debbah and Poor, \{H. Vincent\} and Lajos Hanzo",
note = "Publisher Copyright: {\textcopyright} 2024 IEEE.; 59th Annual IEEE International Conference on Communications, ICC 2024 ; Conference date: 09-06-2024 Through 13-06-2024",
year = "2024",
doi = "10.1109/ICC51166.2024.10622963",
language = "British English",
series = "IEEE International Conference on Communications",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
pages = "3445--3451",
editor = "Matthew Valenti and David Reed and Melissa Torres",
booktitle = "ICC 2024 - IEEE International Conference on Communications",
address = "United States",
}