Conformal Frequency-Diverse Metasurface for Computational AoA Detection

Detecting the angle of arrival (AoA) of electromagnetic waves is an important function in a variety of applications, such as navigation and wireless communication. In this letter, we propose a conformal metasurface antenna (CMA) for detecting the AoA in the horizontal plane. This structure consists of a conformal waveguide with its upper conductor wall fashioned with metamaterial radiators. The resonance frequencies of the metamaterial radiators are selected randomly over a band of operation. The random distribution of resonance frequencies results in patterns that change with frequency and encode information about the AoA of an incident signal into frequency samples, which can be analyzed to retrieve the incident AoA. Using full-wave simulation, we detail the design and operation of the proposed frequency-diverse CMA. We develop and numerically demonstrate a computational processing technique to estimate the AoA from the cross correlation of the signals at the end of coaxial connectors attached to the CMA. The impact of the number of frequency points, bandwidth, and noise on the performance of the device will be illustrated. The proposed device promises a simple and versatile hardware that can detect the AoA from a single receiver and can find application in wireless communication, surveillance, and navigation systems.