Self heterodyne detection for SNR improvement and distributed phase-shift measurements in BOTDA

Zornoza, A.; Sagues, M.; Loayssa, A.;
A. Zornoza is with the Department of Electric and Electronic Engineering, Universidad Pública de Navarra, Campus Arrosadía s/n E-31006 Pamplona, Spain

Journal of Lightwave Technology,
Volume :  PP ,  Issue:99
On page(s): 1 
Digital Object Identifier :  10.1109/JLT.2011.2168808
Date of Publication :   26 Sep 2011

Abstract
In this paper we present a Brillouin optical time domain analysis (BOTDA) sensor that takes advantage of the enhanced characteristics obtained employing self-heterodyne optical detection combined with synchronous demodulation. By employing this technique we increase the sensitivity of the sensor and demonstrate experimentally a 10.75-dB enhancement in the SNR compared to conventional direct-detection systems. This detection scheme also enables distributed measurements of the Brillouin phase-shift in an optical fiber, which can lead to......