Tunable microwave photonic phase shifter based on slow and fast light effects in a tilted fiber Bragg grating

Abstract

A continuously tunable microwave phase shifter based on slow and fast light effects in a tilted fiber Bragg grating (TFBG) written in an erbium/ytterbium (Er/Yb) co-doped fiber is proposed and experimentally demonstrated. By optically pumping the TFBG, the magnitude and phase responses of the cladding mode resonances are changed, which is used to introduce a tunable phase shift to the optical carrier of a single-sideband modulated signal. The beating between the phase-shifted optical carrier and the sideband will generate a microwave signal with the phase shift from the optical carrier directly translated to the generated microwave signal. A tunable phase shifter with a tunable phase shift of 280° at a microwave frequency tunable from 24 to 36 GHz is experimentally demonstrated.

MWP phase shifters integrated in PbS-SU8 waveguides

“…Examples of photonic MPS architectures or technologies are the use of stimulated Brillouin scattering (SBS) [9] or the SOA based implementation [10], whose working principle is based on the slow and fast light phenomenon due to coherent population oscillation (CPO) [11]. Besides, silicon on insulator (SOI) ring resonators have been used to perform the same functionality in narrowband systems [12][13], and fiber Bragg gratings have also been proposed to accurately tune the phase-shift (FBGs) [14]. However, although these technologies allow an efficient control of the microwave phase shift they also present some drawbacks that may limit their practical applications.…”

Integrated Microwave Photonics for Wideband Signal Processing

“…Phase shifters based on the use of various discrete photonic components such as 2D liquid crystal on silicon [12], stimulated Brillouin scattering (SBS) effect in optical fibers [13], vector sum [14], optical filters [15], semiconductor optical amplifiers [16], fiber Bragg gratings (FBGs) [17], and electro-optic modulators [18][19][20], have been demonstrated.…”

Programmable RF photonic phase shifters based on FD-OP for optically controlled beamforming

“…In recent years, various methods for microwave photonic phase shifter have been proposed, for example, based on true-time-delay elements [4][5][6], homodyne mixing techniques [7,8], vector sum techniques [9,10], and nonlinear effects [11][12][13]. It is difficult for the others techniques [7,[9][10][11][12] to operate multiple independent phase shifters, and so the optically controlled beam forming system is complex.…”

“…It is difficult for the others techniques [7,[9][10][11][12] to operate multiple independent phase shifters, and so the optically controlled beam forming system is complex. Recently, Fourier-domain optical processor (FD-OP) is extensively applied in microwave photonic filter [14], photonic microwave phase shifters [15] and true-time-delay beam forming [16].…”