PSK SIMULATION USING MATLAB - DCS LAB

By

Aim: Simulation of PSK modulation and demodulation using MATLAB.

Theory:

Generation of PSK

o In PSK, there are two carriers, with 180 degree phase shift between them (known as antipodal signals). High waveform is multiplied by one of the carrier signal and low waveform is multiplied by the antipodal of the first carrier signal (180 degree shifted carrier signal), thereby generating PSK signal

Demodulation of PSK

o PSK signal has a well defined envelope. Hence envelope detector can be used for demodulation. A decision making circuitry is necessary for message detection.

Code:

clc
close all
clear all
fc1=input('Enter the freq of 1st Sine Wave carrier:');
fp=input('Enter the freq of Periodic Binary pulse (Message):');
amp=input('Enter the amplitude (For Both Carrier & Binary Pulse Message):');
amp=amp/2;
t=0:0.001:1;
c1=amp.*sin(2*pi*fc1*t);
c2=-c1;
subplot(5,1,1);
plot(t,c1)
xlabel('Time')
ylabel('Amplitude')
title('Carrier 1 Wave')
grid on;
subplot(5,1,2)
plot(t,c2)
xlabel('Time')
ylabel('Amplitude')
title('Carrier 2 Wave')
grid on;
m=amp.*square(2*pi*fp*t)+amp;
subplot(5,1,3)
plot(t,m)
xlabel('Time')
ylabel('Amplitude')
title('Binary Message Pulses')
grid on;
for i=0:1000
if m(i+1)==0
mm(i+1)=c2(i+1);
else
mm(i+1)=c1(i+1);
end
end
subplot(5,1,4)
plot(t,mm)
xlabel('Time')
ylabel('Amplitude')
title('Modulated Wave')
grid on;
for i=1:1000;
dm(i+1)=c2(i+1)-mm(i+1);
if dm(i+1)==0;
m1(i+1)=1;
else
m1(i+1)=0;
end
end
subplot(5,1,5)
plot(t,m1)
xlabel('Time')
ylabel('Amplitude')
title('Demodulated Wave')
grid on;

Generated Graph:

 Enter the freq of 1st Sine Wave carrier:20
 Enter the freq of Periodic Binary pulse (Message):5
 Enter the amplitude (For Both Carrier & Binary Pulse Message):4

Comments

Post a Comment

Popular posts from this blog

MICRO LAB EXAMPLES - (ECE3003)

By
Program 1. Write and assemble a program to add the following data and then use the simulator to examine the CY flag. Code: ORG 0000H MOV A,#92H MOV R0,#23H ADD A,R0 JNC L1 INC R7 L1: MOV R1,#66H ADD A,R1 JNC L2 INC R7 L2: MOV R2,#87H ADD A,R2 JNC L3 INC R7 L3: MOV R3,#0F5H ADD A,R3 JNC L4 INC R7 L4: END Program 2. Write and assemble a program to load the values into each register R0-R4 and then push each of these registers onto the stack. Single Step program and examine the stack and the SP register after execution of each instruction. Code: ORG 0000H MOV R0,#25H MOV R1,#35H MOV R2,#45H MOV R3,#55H MOV R4,#65H PUSH 0 PUSH 1 PUSH 2 PUSH 3 PUSH 4 END Program 3. Add the following subroutine to the previous program, single step through the subroutine and examine the RAM locations. After data has been transferred from ROM space into RAM, the subroutine should copy the data from RAM locations starting at 40H to ROM locations starting at 60H. Code: ORG 0000H MOV DPTR,#200H MOV R0,#
Keep reading

Lattice Ladder Structure - (ECE-2006)

By
Image
SYLLABUS (This Document contains Module 7) Module:1 Frequency Analysis of Signals and Systems-1: Review of Discrete -Time Signals and Systems – Classification, Convolution- Z- transform: ROCstability/ causality analysis, DTFT: Frequency response-System analysis. Module:2 Frequency Analysis of Signals and Systems-2: Frequency domain sampling- Sampling rate conversion- Aperiodic correlation estimation-Cepstrum processing- Band limited discrete time signals- Phase and group delay- DFT-Properties. Frequency analysis of signals using DFT-FFT Algorithm-Radix-2 FFT algorithms-Applications of FFT Module:3 Theory and Design of Analog Filters: Design techniques for analog low pass filter -Butterworth and Chebyshev approximations, frequency transformation, Properties -Constant group delay and zero phase filters Module:4 Design of IIR Digital Filters: IIR filter design: IIR filter Design - Bilinear and Impulse Invariant Techniques- Spectral transformation of Digital filters
Keep reading

Line Coding PSD - (ECE-4001)

By
Image
SYLLABUS (This Document contains Module 3)  Module:1 Sampling & Quantization: Model of digital communication system – Review of sampling – Quantization – Uniform & non-uniform quantization. Module:2 Waveform Coding Techniques:  Pulse Code Modulation – Quantization noise and signal to quantization noise ratio – Companding (A law and μ law) - Delta modulation. Module:3 Line Codes: Representation of Line Codes – Properties and applications of Line codes – Power Spectral Density of NRZ unipolar, NRZ Polar, NRZ Bipolar and Manchester. Module:4 Baseband System: Inter Symbol Interference – Nyquist criterion for distortion less transmission – Raised cosine spectrum – Correlative coding – Eye pattern – Equalization. Module:5 Bandpass System-I: Gram-Schmidt orthogonalization procedure – Correlation Receiver – QAM- Generation and Detection of Coherent system (BASK, BFSK, BPSK, QPSK, MSK) – Error performance. Module:6 Bandpass System-II: Matched Filter
Keep reading