“…In this case, a suitable receiver scheme, combining optical and electrical heterodyne detection, is needed. Results report an increase in the threshold value of the input peak power before onset of nonlinear effects, allowing for a better sensing performance compared to single-longitudinal mode lasers.Introduction and theory: Distributed Brillouin-based optical fibre sensors have been widely reported in recent years owing to their possibilities to perform distributed strain and temperature sensing along an optical fibre [1,2]. In particular, sensors based on stimulated Brillouin scattering (SBS) require access to both fibre-ends and the use of two optical fibres to distinguish between strain and temperature effects, owing to the strain-temperature cross-sensitivity of the Brillouin gain [1].…”