Question 1) Why we require optical fiber cables? Describe different kinds of fiber optic cables used in the industry.
Question 2) A 6 km optical link consists of multimode step index fiber with a core refractive index of 1.5 and a relative refractive index difference of 1%. Estimate the delay difference between the slowest and fastest mode at fiber output and rms pulse broadening due to inter-modal dispersion on the link.
Question 3) Write down the differences between TE, TM and FIE, modes?
Question 4) What do you mean by responsivity and how it depends on the wavelength of a photodiode?
Question 5) What do you mean by WDM and write the reasons for its development as a major communication technology?
Question 6) Determine E and H component of a cylindrical single mode fiber using Maxwell equations.
Question 7) A 1550 nm SM digital fiber optical link needs to operate at 565Mb/s over 50 km without repeaters. A single mode InGaAsp LD launches an average power of -13 dBm into the fiber. The fiber has a loss of 0.35 dB/km & there is splice with a loss of 0.1dB every km. The coupling loss at the receiver is 0.5 dB and receiver uses InGaAsAPD with sensitivity of -39 dBm, excess noise penalties are predicted to be 1.5 dB. Set up the power budget link and the system margins.
Question 8) What do you mean by Noise? List and describe different kinds of noises encountered in an optical communication link?