All-optical pulse compression of broadband microwave signal based on stimulated Brillouin scattering

TL;DR

This paper demonstrates a novel all-optical method for compressing broadband microwave pulses using stimulated Brillouin scattering in optical fibers, combining theoretical derivation and experimental validation.

Contribution

It introduces a new all-optical pulse compression technique based on SBS, with both theoretical analysis and experimental proof-of-concept.

Findings

Successfully compressed a 1 GHz sweep range microwave signal.

The experimental results match the theoretical auto-correlation model.

Demonstrated feasibility of all-optical broadband microwave pulse processing.

Abstract

Pulse compression processing based on stimulated Brillouin scattering (SBS) in an optical fiber is theoretically and experimentally demonstrated. Broadband microwave signal is electro-optically modulated onto the pump lightwave that is launched into one end of the fiber. Acoustic wave in the fiber inherits the amplitude and phase information of the pump lightwave and thus the coupling between the acoustic wave and pump lightwave leads to the auto-correlated process of the pump lightwave as well as the modulated microwave signal. Derivation of the SBS coupling equations shows that the short-pulse probe lightwave amplified by the pump lightwave possesses the nature of auto-correlation formula. All-optical pulse compression of the broadband microwave signal is implemented after a subtraction between the detected probe pulse with and without SBS. A proof-of-concept experiment is carried out. The pulse compression of a linear frequency-modulated microwave signal with 1 GHz sweep range at the carrier frequency of 4.3 GHz is successfully realized, which well matches the theoretical analysis.