blob: f298f9d94f37190f54df04d50664f1f0946d50ea (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
|
// Example 2.7.13 page 2.31
clc;
clear;
n1=1.447; //refractive index of core
n2=1.442; //refractive index of cladding
lamda=1.3d-6; //Wavelength
a=3.6d-6; //core radius
NA=sqrt(n1^2 - n2^2); //computing Numerical aperture
v= 2*%pi*a*NA/lamda; //computing normalized frequency
printf("As normalized frequency is %.2f which is less than 2.405, this fiber will permit single mode transmission",v);
lamda_cut_off=v*lamda/2.405
lamda_cut_off=lamda_cut_off*10^9
printf("\n\nSingle mode operation will occur above this cut off wavelength of %.2f nm",lamda_cut_off);
printf("\n\n NOTE - Calculation error in the book.\n(1.447^2 - 1.442^2)^0.5=0.121; they have taken 0.141\nHence calculations after that are incorrect in the book");
//Calculation error in the book.(1.447^2 - 1.442^2)^0.5=0.121; they have taken 0.141.Hence calculations after that are incorrect in the book.
//They have taken radius as 2.6d-6, whereas in question it is given 3.6d-6.
//answers in the book
//Normalized frequency is 1.77.(incorrect)
//cut off wavelength 956nm.(incorrect)
|
