The Effects Of Temperature Variation, Pressure, And Bends On The Quality Of The Output Signal Generated By Continuous Wave (Cw) Laser In Single Mode Optical Fiber

ABSTRACT

Information signals need to be transmitted fast, efficiently and accurately. Optical fiber cables

are the transmission medium used in optical fiber communications. Optical fiber communication

has exhibited many advantages over other means of communication. However, natural and

physical environment within the vicinity where the cable is installed poses a great challenge to

signal transmission. The effect of bends on the quality of the output signal generated by a

continuous wave (CW) laser on a single mode optical fiber was investigated. A single mode

optical fiber cable was subjected to Macrobends in the range of 5mm-50mm bend radius. An

optical signal from a CW laser emitting beams in the range of 800nm-880nm was transmitted

through the cable. Transmission percentage and variation in peaks were noted and graphs plotted

corresponding to each bend radius. Transmission percentage was found to be proportional to the

size of the bend radius. Similarly, the single mode optical fiber cable was subjected to pressure

using various weights in the range of 1-6kg. The weights develop stress on the cable. The optical

signal from the CW laser was transmitted and its transmission quality analyzed. Various

transmission graphs were plotted for each pressure exerted. Transmission percentage and the

nature of peaks changed according to the weight applied. This study showed that increased

pressure resulted in increased attenuation which resulted in minimal or no signal transmission.

The single mode optical fiber cable was placed in thermal chamber where temperature was

regulated. The range of temperatures considered corresponded to the ones of Nakuru area with

changes in the range of 13 0C to 400C. An Optical signal was transmitted and various

transmission graphs were plotted for each temperature change. Transmission percentage and the

nature of peaks were noted for each temperature. The temperatures under study had no effect on the quality of the output signal since transmission graph appeared similar.