Absorption Line Shift with Temperature and Pressure: Impact on Laser-Diode-Based H 2 O Sensing at 1.393 (mu)m

High-resolution absorption measurements of the H2 O line in the v1 + v3 band at 1.3928 (mu)m were made in the temperature range of 296 -1100 K by use of an InGaAsP distributed-feedback laser diode operating at 1.39 (mu)m. Spectral line shift, line strength, and N2 broadening on the water-vapor line and their impact on the accuracy of optical-absorption-based gas sensing have been investigated. The results obtained were compared with values obtained from the HITRAN database and values reported in the literature, facilitating H2 O sensing in a nonstandard temperature and pressure environment.