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Title: Electrically controlled phased array OAM radar
Control of orbital angular momentum (OAM) offers the potential for increases in control, sensitivity, and security for high-performance microwave systems. OAM is characterized by an integer OAM mode where zero represents the case of a plane wave. Microwaves with a nonzero OAM mode propagate with a helical wavefront. Orthogonal OAM modes can be used to carry distinct information at the same frequency and polarization, increasing the data rate. The OAM waveform may also increase radar detection capability for certain shaped objects. OAM can be induced by broadcasting a plane wave through a spatial phase plate (SPP) dielectric which introduces an azimuthally dependent phase delay. However, SPPs are frequency-specific, which presents an obstacle for harnessing OAM in frequency-modulated communication systems and wide-bandwidth radar. In this study, we develop a circular phased array to synthesize the desired vortex-shaped wavefront. This approach offers a critical advantage: the phases of all antenna elements are easily programmable under different frequencies. As a result, transmission and reception of the OAM beam can be controlled with great flexibility, making it operable over a wide frequency spectrum, which leverages OAM radar functionality and performance. In this paper, we will investigate a wide-bandwidth radar with OAM mode-control and signal processing.  more » « less
Award ID(s):
1647095
PAR ID:
10207232
Author(s) / Creator(s):
; ; ;
Editor(s):
Raynal, Ann M.; Ranney, Kenneth I.
Date Published:
Journal Name:
SPIE Defense + Commercial Sensing, Proc Vol 11408, Radar Sensor Technology XXIV
Volume:
11408
Page Range / eLocation ID:
5
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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