From b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b Mon Sep 17 00:00:00 2001
From: priyanka
Date: Wed, 24 Jun 2015 15:03:17 +0530
Subject: initial commit / add all books

---
 2300/CH21/EX21.13.1/Ex21_1.sce | 25 +++++++++++++++++++++++++
 2300/CH21/EX21.13.2/Ex21_2.sce | 15 +++++++++++++++
 2300/CH21/EX21.13.3/Ex21_3.sce | 13 +++++++++++++
 3 files changed, 53 insertions(+)
 create mode 100755 2300/CH21/EX21.13.1/Ex21_1.sce
 create mode 100755 2300/CH21/EX21.13.2/Ex21_2.sce
 create mode 100755 2300/CH21/EX21.13.3/Ex21_3.sce

(limited to '2300/CH21')

diff --git a/2300/CH21/EX21.13.1/Ex21_1.sce b/2300/CH21/EX21.13.1/Ex21_1.sce
new file mode 100755
index 000000000..77e98afac
--- /dev/null
+++ b/2300/CH21/EX21.13.1/Ex21_1.sce
@@ -0,0 +1,25 @@
+//scilab 5.4.1
+//Windows 7 operating system
+//chapter 21 Communication Systems
+clc
+clear
+Npe=6*10^10//Npe=peak electron concentration for the E layer in m^-3
+Npf=10^12//Npf=peak electron concentration for the F layer in m^-3
+fCE=9*sqrt(Npe)//fCE=critical frequency for the E layer
+format("v",5)
+disp("MHz",fCE/10^6,"Critical frequency for the E layer is =")
+fCF=9*sqrt(Npf)//fCF=critical frequency for the F layer
+format("v",5)
+disp("MHz",fCF/10^6,"Critical frequency for the F layer is =")
+R=6400//R=radius of the earth in km
+He=110//He=height of the E layer above the earth surface in km
+ime=asind(R/(R+He))//ime=angle corresponding to maximum frequency fmE for E layer in degrees
+format("v",3)
+fmE=fCE*secd(ime)//fmE=maximum frequency reflected from the E layer
+disp("MHz",fmE/10^6,"The maximum frequency reflected from the E layer is =")
+Hf=250//Hf=height of the F layer above the earth surface in km
+imf=asind(R/(R+Hf))//imf=angle corresponding to maximum frequency fmF for F layer in degrees
+format("v",3)
+fmF=fCF*secd(imf)//fmF=maximum frequency reflected from the F layer
+disp("MHz",fmF/10^6,"The maximum frequency reflected from the F layer is =")
+
diff --git a/2300/CH21/EX21.13.2/Ex21_2.sce b/2300/CH21/EX21.13.2/Ex21_2.sce
new file mode 100755
index 000000000..ce9e2c465
--- /dev/null
+++ b/2300/CH21/EX21.13.2/Ex21_2.sce
@@ -0,0 +1,15 @@
+//scilab 5.4.1
+//Windows 7 operating system
+//chapter 21 Communication Systems
+clc
+clear
+R=6400//R=radius of the earth in km
+He=110//He=height of the E layer above the earth surface in km
+ime=asin(R/(R+He))//ime=angle corresponding to maximum frequency fmE for E layer in radian
+format("v",10)
+o=(%pi/2)-ime//o=angle made by the incident ray at the centre of the earth in degrees
+format("v",5)
+L=2*o*R//L=maximum distance between the transmitting and the receiving points on the earth surface for single hop transmission of the radiowave reflected from the E layer
+format("v",5)
+disp("km",L,"The maximum distance for single hop transmission is =")
+//Answer given in textbook is 2459 km which is incorrect as it is actually around 2356 km.
diff --git a/2300/CH21/EX21.13.3/Ex21_3.sce b/2300/CH21/EX21.13.3/Ex21_3.sce
new file mode 100755
index 000000000..86ad505d7
--- /dev/null
+++ b/2300/CH21/EX21.13.3/Ex21_3.sce
@@ -0,0 +1,13 @@
+//scilab 5.4.1
+//Windows 7 operating system
+//chapter 21 Communication Systems
+clc
+clear
+//fc=9*sqrt(Np)
+fc=3*10^6//fc=critical frequency in Hz
+Np=(fc^2)/81//Np=electron concentration at the reflecting point
+//h=height of the reflecting point from the bottom of the layer
+//Np=(5*10^10)+(10^9*h)....(given)
+h=(Np-(5*10^10))/10^9
+H=100//H=height above the surface of the earth in km
+disp("km",h+H,"The required height above the ground is =")
-- 
cgit