a. Estimate (i) The maximum possible Bandwidth or the link assuming no ISI. (ii) The pulse dispersion per unit length.

b. (iii) The Bandwidth length product.

Mumbai University > Electronics and telecommunication > Sem 7 > optical communication and networks

Marks: 05

Years: DEC 2015

(a) The maximum possible optical bandwidth which is equivalent to the maximum possible bit rate (for return to zero pulses) assuming no ISI may be obtained, where:

$B_{opt} = B_T= \dfrac 1{2τ} = \dfrac 1{0.2×10^{-6}} = 5 MHZ$

(b) The dispersion per unit length may be acquired simply by dividing the total dispersion by the total length of the fiber:

Dispersion $= \dfrac {0.1×10^{-6}}{ 15} =6.67 ns \space Km^{-1}$

(c) The bandwidth–length product may be obtained in two ways. Firstly by simply multiplying the maximum bandwidth for the fiber link by its length. Hence:

$B_{opt}L = 5 MHz × 15 km = 75 MHz\space km$

Alternatively, it may be obtained from the dispersion per unit length

$B_{opt}L = \dfrac 1{ 2×6.67×10^{-6}} = 75 MHz\space km$