The first demonstration of an optically steered microwave phased array antenna using true-time-delay

Subbaraman

Optoelectronic Devices and Integration II

2007

In this paper, a highly dispersive pure silica photonic crystal fiber is designed and fabricated with maximum chromatic dispersion value of about -600 ps/(nm·km) around 1.55 µm wavelength region. This kind of a photonic crystal fiber structure is suitable for high dispersion application in photonic crystal fiber array based phased array antenna systems.A four-element true-time delay module is constructed using the fabricated highly dispersive photonic crystal fibers. The true time delay value of 10.5m PCF is characterized to provide maximum delay of 31.3ps with 32nm optical wavelength tuning range, which is sufficient to scan from -45 o to 45 o for a 4-element PAA subarray having 1.3cm spacing. A multiple-beam optical beamformer is designed based on the fabricated highly dispersive photonic crystal fibers. The true-time delay beamformer can be programmed to continuously sweep the antenna aperture independently for multiple RF beams. Since the dispersion of the fabricated photonic crystal fibers is as high as -600 ps/nm·km at 1550 nm, compared to telecom SMF-28 that has a dispersion parameter of 18 ps/nm·km, the length of delay line is reduced by a factor of 33.

Section: Introductionmentioning

confidence: 99%

Highly dispersive photonic crystal fiber for beamforming

Subbaraman

Optoelectronic Devices and Integration II

2007

IEEE Microw. Wireless Compon. Lett.

“…Many TTD phase shifters have been proposed over the years. These include switched delay line [2], dispersive fiber prism [3] and fiber grating devices [4]. Though promising, these phase shifters are complex and usually expensive to implement.…”

Section: Introductionmentioning

confidence: 99%

Wide-band RF photonic second order vector sum phase-shifter

Bui

Mitchell

Ghorbani

et al. 2005

Review of Scientific Instruments

“…The fiber transfer delay (FTD), as an essential characteristic for fiber transmission, becomes a significant parameter in many optical fiber applications, such as optical communication [1][2][3], fiber timing distribution system [4][5][6], phased array antenna [7][8][9] and some other large-scale scientific or engineering facilities [10][11][12][13]. Up to now, many techniques for FTD measurement in time domain or frequency domain have been developed and successfully employed [14][15][16][17][18][19][20][21].…”

Section: Introductionmentioning

confidence: 99%

Accurate and fast fiber transfer delay measurement based on phase discrimination and frequency measurement

Dong

Wang

Gao

et al. 2016

An accurate and fast fiber transfer delay measurement method is demonstrated. As a key technique, a simple ambiguity resolving process based on phase discrimination and frequency measurement is used to overcome the contradiction between measurement accuracy and system complexity. The optimized system achieves a high accuracy of 0.3 ps with a 0.1 ps resolution, and a large dynamic range up to 50 km as well as no dead zone. References and links