Hallett, Stephen H.; Partridge, Matthew; James, Stephen; Tiwari, Ashutosh; Farewell, Timothy S.; Tatam, Ralph P.
(SPIE - International Society for Optics and Photonics, 2017-04-23)
The use of an optical fibre long period grating (LPG) as a soil moisture sensor is reported. Characterization of the device in both clay and sandy soils revealed a sensitivity to moisture levels in the range 10-50%, and ...