Transmission Loss Change Research Articles

Effect of Ambient Temperature on Infrared Transmission Through a Glass Fiber

Recent progress in reducing the losses in optical fibers1 has increased the possibility that such fibers might be used as dielectric waveguides in future optical communication systems.2 The loss properties of such fibers are therefore of interest. This note concerns the measured change in transmission loss of a glass fiber for an ambient temperature variation of −196°C to +200°C. The results indicate that the loss in glass fibers varies only slightly with temperature.

VLF Transmission Loss Calculated From Spectral Analyses of Atmospherics

VLF atmospheric data recorded during four 6‐hour periods was analyzed to evaluate the feasibility of employing a new technique to determine attenuation rates over a particular path. The technique involves recording the spectral components of atmospherics arriving from within an adjustable azimuthal direction. Changes in transmission loss, deduced from the observed spectra, between day and night conditions for an approximate 3000‐km path indicate differences in total transmission loss of about 15 dB at 5 kHz, 1 or 2 dB at 10 kHz and 40 kHz, and a negative loss, or gam, between 12kHz and 30kHz.