Article

Experimental demonstration of a phased-array antenna optically controlled with phase and time delays

Applied Optics (Impact Factor: 1.78). 09/1996; 35(26):5293-300. DOI: 10.1364/AO.35.005293
Source: PubMed

ABSTRACT The experimental demonstration and the far-field pattern characterization of an optically controlled phased-array antenna are described. It operates between 2.5 and 3.5 GHz and is made of 16 radiating elements. The optical control uses a two-dimensional architecture based on free-space propagation and on polarization switching by N spatial light modulators of p × p pixels. It provides 2(N-1) time-delay values and an analog control of the 0 to 2π phase for each of the p × p signals feeding the antenna (N = 5, p = 4).

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    • "Free-space approaches typically use a series of spatial light modulators to select the paths for arrays of beams [18]–[20] or acousto-optic modulation [21], [22]. The advantage of free space is low weight and equal ease of implementing long and short delays. "
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