Silixa produces the world’s highest performance distributed temperature sensor ULTIMA™. The ULTIMA has a sampling resolution of 12.5cm and a spatial resolution of just 25cm – 30cm. Even with this breakthrough spatial resolution (all other commercial DTSs have a spatial resolution in excess of 1m) the ULTIMA matches the very best alternative units for temperature resolution, achieving better than 0.01°C. Further, the ULTIMA is optimised for high temperature measurements and has been successfully tested on fibres at temperatures above 700°C, achieving a 29cm spatial resolution over a step transition from 25°C to 700°C.
in more detail…
The ULTIMA illuminates the sensing fibre with a series of sub-nanosecond duration pulses. As the pulses propagate down the fibre, a small amount of light is backscattered towards the laser source. The majority of the backscatter, Rayleigh light, is at the same optical wavelength as the laser and is not temperature sensitive. However, a small proportion of the light is scattered by the Raman process and is temperature dependent. By recording the backscattered Raman light as a function of time, the temperature at all points along the fibre can be determined.
There are many proprietary technical advances in the ULTIMA which enable it to leapfrog the performance of existing DTS systems. The key breakthrough is in maintaining a fine temperature resolution and class-leading measurement stability while operating with the extremely low light levels and microwave electronics required for a 25cm spatial resolution.