VI-Sem-SP Lab-ECE

7/30/2019 VI-Sem-SP Lab-ECE

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SIGNAL PROCESSING LAB

PREPARED BY

Smt. B.Rajeswari Mr. M.K. Linga MurthyM.Tech M.Tech

Assistant Professor. Assistant Professor.Dept., of ECE. Dept., of ECE.

Department of Electronics and Communications Engineering,Lakireddy Bali Reddy College of Engineering

(AUTONOMOUS),L.B.Reddy Nagar, MYLAVARAM 521230.


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Lakireddy Bali Reddy College of Engineering (AUTONOMOUS)

L.B.Reddy Nagar, MYLAVARAM 521230.Krishna Dist., (A.P.)

Signal Processing Laboratory

Name :

Regd.No :

Course : B.Tech (VI Semester). Branch :ECE

Academic Year : 2012-2013


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P873 SIGNAL PROCESSING LAB

Lecture : 3 Periods/week Internal Marks : 25

External Marks : 75

Credits : 2 External Examination : 3 Hrs--------------------------------------------------------------------------------------------------

LIST OF EXPERIMENTS:

USING TMS320C67X

1 Generation of Signals

2 Linear Convolution

3 Implementation of a FIR filter

4 Implementation of an IIR filter

5 Calculation of FFT

USING MATLAB

1 Generation of Discrete time Signals

2 Verification of Sampling Theorem

3 FFT and IFFT

4 Time & Frequency response of LTI systems

5 Linear and Circular Convolution through FFT

6 Design of FIR filters (window design)

7 Design of IIR filters (Butterworth &Chebychev)

ADDITIONAL EXPERIMENTS

1 Verify decimation.

2 Verify interpolation.


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1. INTRODUCTION TO DSP PROCESSORS

A signal can be defined as a function that conveys information, generally about

the state or behavior of a physical system. There are two basic types of signals viz

Analog (continuous time signals which are defined along a continuum of times) andDigital (discrete-time).

Remarkably, under reasonable constraints, a continuous time signal can beadequately represented by samples, obtaining discrete time signals. Thus digital signal

processing is an ideal choice for anyone who needs the performance advantage of digital

manipulation along with todays analog reality.

Hence a processor which is designed to perform the special operations(digital

manipulations) on the digital signal within very less time can be called as a Digital signal

processor. The difference between a DSP processor, conventional microprocessor and a

microcontroller are listed below.

Microprocessor or General Purpose Processor such as Intel xx86 or Motorola 680xx

familyContains - only CPU

No RAM

No ROM

No I/O ports

No Timer

Microcontroller such as 8051 family

Contains - CPU

RAM ROM

I/O ports

Timer &

Interrupt circuitrySome Micro Controllers also contain A/D, D/A and Flash Memory

DSP Processors such as Texas instruments and Analog Devices

Contains - CPU

RAM

ROM I/O ports

Timer

Optimized for fast arithmetic- Extended precision- Dual operand fetch- Zero overhead loop- Circular buffering


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The basic features of a DSP Processor are

Feature Use

Fast-Multiply accumulate Most DSP algorithms, including

filtering, transforms, etc. are

multiplication- intensive

Multiple access memory

architecture

Many data-intensive DSP operations

require reading a program instruction

and multiple data items during eachinstruction cycle for best performance

Specialized addressing modes Efficient handling of data arrays andfirst-in, first-out buffers in memory

Specialized program control Efficient control of loops for manyiterative DSP algorithms. Fast interrupt

handling for frequent I/O operations.

On-chip peripherals and I/O

interfaces

On-chip peripherals like A/D converters

allow for small low cost system designs.Similarly I/O interfaces tailored forcommon peripherals allow clean

interfaces to off-chip I/O devices.


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2. ARCHITECTURE OF 6713 DSP PROCESSOR

This chapter provides an overview of the architectural structure of theTMS320C67xx DSP, which comprises the central processing unit (CPU), memory, and

on-chip peripherals. The C67xE DSPs use an advanced modified Harvard architecture

that maximizes processing power with eight buses. Separate program and data spacesallow simultaneous access to program instructions and data, providing a high degree of

parallelism. For example, three reads and one write can be performed in a single cycle.

Instructions with parallel store and application-specific instructions fully utilize thisarchitecture. In addition, data can be transferred between data and program spaces. Such

Parallelism supports a powerful set of arithmetic, logic, and bit-manipulation operations

that can all be performed in a single machine cycle. Also, the C67xx DSP includes thecontrol mechanisms to manage interrupts, repeated operations, and function calling.

Fig 2 1 BLOCK DIAGRAM OF TMS 320VC 6713


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Bus Structure

The C67xx DSP architecture is built around eight major 16-bit buses (fourprogram/data buses and four address buses):

The program bus (PB) carries the instruction code and immediate operands from

program memory. Three data buses (CB, DB, and EB) interconnect to various elements, such as the

CPU, data address generation logic, program address generation logic, on-chip

peripherals, and data memory.

The CB and DB carry the operands that are read from data memory.

The EB carries the data to be written to memory.

Four address buses (PAB, CAB, DAB, and EAB) carry the addresses needed forinstruction execution.

The C67xx DSP can generate up to two data-memory addresses per cycle using thetwo auxiliary register arithmetic units (ARAU0 and ARAU1). The PB can carry data

operands stored in program space (for instance, a coefficient table) to the multiplier andadder for multiply/accumulate operations or to a destination in data space for data moveinstructions (MVPD and READA). This capability, in conjunction with the feature of

dual-operand read, supports the execution of single-cycle, 3-operand instructions such as

the FIRS instruction. The C67xx DSP also has an on-chip bidirectional bus for accessing

on-chip peripherals. This bus is connected to DB and EB through the bus exchanger inthe CPU interface. Accesses that use this bus can require two or more cycles for reads

and writes, depending on the peripherals structure.

Central Processing Unit (CPU)

The CPU is common to all C67xE devices. The C67x CPU contains:

40-bit arithmetic logic unit (ALU)

Two 40-bit accumulators

Barrel shifter

17 17-bit multiplier

40-bit adder

Compare, select, and store unit (CSSU)

Data address generation unit

Program address generation unit

Arithmetic Logic Unit (ALU)

The C67x DSP performs 2s-complement arithmetic with a 40-bit arithmetic logicunit (ALU) and two 40-bit accumulators (accumulators A and B). The ALU can also

perform Boolean operations. The ALU uses these inputs:

16-bit immediate value

16-bit word from data memory

16-bit value in the temporary register, T

Two 16-bit words from data memory

32-bit word from data memory


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40-bit word from either accumulator

The ALU can also function as two 16-bit ALUs and perform two 16-bit operations

simultaneously.

Fig 2 2 ALU UNITAccumulators

Accumulators A and B store the output from the ALU or the multiplier/adder

block. They can also provide a second input to the ALU; accumulator A can be an inputto the multiplier/adder. Each accumulator is divided into three parts:

Guard bits (bits 3932)

High-order word (bits 3116)

Low-order word (bits 150)Instructions are provided for storing the guard bits, for storing the high- and the low-

order accumulator words in data memory, and for transferring 32-bit accumulator words

in or out of data memory. Also, either of the accumulators can be used as temporarystorage for the other.

Barrel Shifter

The C67x DSP barrel shifter has a 40-bit input connected to the accumulators or

to data memory (using CB or DB), and a 40-bit output connected to the ALU or to data

memory (using EB). The barrel shifter can produce a left shift of 0 to 31 bits and a rightshift of 0 to 16 bits on the input data. The shift requirements are defined in the shift count

field of the instruction, the shift count field (ASM) of status register ST1, or in temporary

register T (when it is designated as a shift count register).The barrel shifter and theexponent encoder normalize the values in an accumulator in a single cycle. The LSBs of

the output are filled with 0s, and the MSBs can be either zero filled or sign extended,

depending on the state of the sign-extension mode bit (SXM) in ST1. Additional shiftcapabilities enable the processor to perform numerical scaling, bit extraction, extended

arithmetic, and overflow prevention operations.


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Multiplier/Adder Unit

The multiplier/adder unit performs 17 _ 17-bit 2s-complement multiplication witha 40-bit addition in a single instruction cycle. The multiplier/adder block consists of

several elements: a multiplier, an adder, signed/unsigned input control logic, fractional

control logic, a zero detector, a rounder (2s complement), overflow/saturation logic, and a

16-bit temporary storage register (T). The multiplier has two inputs: one input is selectedfrom T, a data-memory operand, or accumulator A; the other is selected from program

memory, data memory, accumulator A, or an immediate value. The fast, on-chipmultiplier allows the C54x DSP to perform operations efficiently such as convolution,

correlation, and filtering. In addition, the multiplier and ALU together execute

multiply/accumulate (MAC) computations and ALU operations in parallel in a single

instruction cycle. This function is used in determining the Euclidian distance and inimplementing symmetrical and LMS filters, which are required for complex DSP

algorithms. See section 4.5, Multiplier/Adder Unit, on page 4-19, for more details about

the multiplier/adder unit.

Fig 2 3 MULTIPLIER/ADDER UNIT

These are the some of the important parts of the processor and you are instructed to go

through the detailed architecture once which helps you in developing the optimized code

for the required application.


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INDEX

CYCLE ----- I

S.No Date Name of the Experiment Marks Signature

1 Generation of Signals

2 Linear Convolution

3 Implementation of a FIR filter.

4Implementation of an IIR filter.

5 Calculation of FFT.

CYCLE ----- II

S.No Date Name of the Experiment Marks Signature

1 Generation of discrete timeSignals

2Verification of sampling

theorem.

3 FFT and IFFT

4Time and Frequency response

of LTI Systems

5Linear and Circular

Convolution through FFT.

6Design of FIR filters

(window design)

7Design of IIR filters

(Butterworth& Chebychev)


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CYCLE ------------I


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1. GENERATION OF DIFFERENT SIGNALS

Aim: Generating different signals using C.

Equipments: Operating System Windows XPConstructor - Simulator

Software - CCStudio 2

Theory:

Procedure:

1. Open CC Studio and Create a new project(projnew).

2. Open source file and write the program and save the file with .C

extension.(filenewsource file).

3. Add source files to project (projadd files to projectfilename.c).

4. Add library files to project (path: C:ti\C6000\Cgtools\lib\rts6700.lib).

5. Add linker command files to project (path: C:ti\tutorial\dsk6711\hello1\hello.cmd).6. Compile and build the program (projcompile file, build).

7. Load program (fileload program: Look in: proj. Out).

8. Run the program and observe the result (debugrun).


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Program:

#include

#include

#define pi 3.14159

int t,L1,L2,N1;

float x[1000],x1[1000],x2[1000];

void main()

{

printf("Enter the Length of required wave");

scanf("%d",&L1);

printf("Enter the values for wave");

for(t=0;t


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Output:

Result:

Precautions:

1. Check out source file is with .c extension or not.

2. Check out the files added were correct or not.3. Do not add more than one source file to the project at a time.

4. If only building the project is having error check the processor setup.

5. Dont delete any file or folder without informing the system administrator or

lab in-charge.

Viva-Voce Questions:

1. Define signal and give examples of operations on signals.

2. What are basic signals.3. Differentiate continuous and digital signals.

4. What are the applications of signals.

5. Define energy and power signals.

Lab In-charge


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2. LINEAR CONVOLUTION

Aim:To compute the response of a discrete LTI system with input sequence x(n) and

impulse response h(n) by using linear convolution.

Equipments:

Operating System Windows XP

Constructor - Simulator


Theory:

Procedure:

1. Open CC Studio and Create a new project(projnew).

2. Open source file and write the program and save the file with .C extension.

(file

new

source file).3. Add source files to project (projadd files to projectfilename.c).

4. Add library files to project (path: C:ti\C6000\Cgtools\lib\rts6700.lib).

5. Add linker command files to project(path: C:ti\tutorial\dsk6711\hello1\hello.cmd).

6. Compile and build the program (projcompile file, build).




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Program:

// Linear convolution program in c language using CCStudio

#include

int x[15],h[15],y[15];

main()

{

int i,j,m,n;

printf("\n enter value for m");

scanf("%d",&m);

printf("\n enter value for n");

scanf("%d",&n);

printf("Enter values for i/p x(n):\n");

for(i=0;i


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OUTPUT:

Result:

Precautions:

Check out source file is with .c extension or not.

Check out the files added were correct or not.

Do not add more than one source file to the project at a time.

If only building the project is having error check the processor setup.

Dont open any other folders or files.

Dont delete any file or folder without informing the system administrator or lab in-

charge.

VIVA -VOCE QUESTIONS:

What is the need of convolution

Why DFT does not support Linear Convolution.

How to obtain the response of discrete LTI system from Linear Convolution

What are different steps required to execute the DSP program in CCS.

How to create project in CCS.

What are different files to be added for project, to execute the program

Lab In-charge


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3. IMPLEMENTATION OF FIR FILTER

Aim:To design FIR filters using c program & implement in CCS software

Equipments:




Theory:

Procedure:

1. Open CC Studio and Create a new project (projnew).


extension.(filenewsource file).3. Add source files to project (projadd files to projectfilename.c).

4. Add library files to project (path: C:ti\C6000\Cgtools\lib\rts6700.lib).5. Add linker command files to project (path: C:ti\tutorial\dsk6711\hello1\hello.cmd).


7. Load program (fileload program: Look in: proj.Out).



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Program:

#include

#include

#define pi 3.1415

int n,N,c;

float wr[64],wt[64];

void main()

{

printf("\n enter no. of samples,N= :");

scanf("%d",&N);

printf("\n enter choice of window function\n 1.rect \n 2. triang \n c= :");

scanf("%d",&c);

printf("\n elements of window function are:");

switch(c)

{

case 1:

for(n=0;n


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Output:

Result:

Precautions: Check out source file is with .c extension or not.






charge.

Viva -voce questions:

What are the advantages of FIR filter?

What is the need of usage of windows?

What are different steps required to execute the DSP program in CCS.

How to create project in CCS.

What are different files to be added for project, to execute the program?

Lab In-charge


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4. IMPLEMENTATION OF IIR FILTERS

Aim:To design and implement IIR (LPF/HPF) filters using c program & implement in CCS

software.

Equipments:




Theory:

Procedure:1. Open CC Studio and Create a new project (projnew).


extension.(filenewsource file).

3. Add source files to project (projadd files to projectfilename.c).

4. Add library files to project (path: C:ti\C6000\Cgtools\lib\rts6700.lib).5. Add linker command files to project (path:

C:ti\tutorial\dsk6711\hello1\hello.cmd).





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Program:

// iir filter implementation.

#include

#include

int i,w,wc,c,N;

float H[100];

float mul(float, int);

void main()

{

printf("\n enter order of filter ");

scanf("%d",&N);

printf("\n enter the cutoff freq ");

scanf("%d",&wc);

printf("\n enter the choice for IIR filter 1. LPF 2.HPF ");

scanf("%d",&c);

switch(c)

{

case 1:

for(w=0;w


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a*=a;

return(a);

}

OUTPUT:

Result:

PRECAUTIONS:







charge.

VIVA -VOCE QUESTIONS:

What are advantages of IIR Filter over FIR Filter?

What are different windows for IIR filter?

What is the need of window.

Which are raised cosine windows?

What are characteristics of LPF and HPF?

Lab In-charge


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5. CALCULATION OF FAST FOURIER TRANSFORM

Aim:To verify Fast Fourier Transform using c program & implement in CCS software.

Equipments:




Theory:


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Procedure:

1. Open CC Studio and Create a new project (projnew).

2. Open source file and write the program and save the file with .C extension.

(filenewsource file).

3. Add source files to project (projadd files to projectfilename.c).4. Add library files to project (path: C:ti\C6000\Cgtools\lib\rts6700.lib).

5. Add linker command files to project (path: C:ti\tutorial\dsk6711\hello1\hello.cmd).




Program:

#include

#include

#define Pi 3.142857

int x[20],N,n,k;

float XReP[20],XImP[20],X[20],MSofX[20],PSofX[20];

void main()

{

printf("Enter the length of discrete sequence x(n):N=");

scanf("%d",&N);

printf("Enter the discrete sequence x(n):\n");

for(n=0;n


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XImP[k]=-XImP[k];

PSofX[k]=atan(XImP[k]/XReP[k]);

}

printf("\nDiscrete sequence x(n)=");

for(n=0;n


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Result:

Precautions:







charge.

Viva-voce questions:

What is Fast Fourier Transform

How to obtain Fast Fourier Transform of a sequence x(n) What are different types of FFT algorithms

Explain clearly how computational efficiency increases through FFT

How to compute IDFT through FFT

How to obtain response of the system from FFT.

Lab In-charge


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CYCLE ------- II


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1. GENERATION OF DISCRETE TIME SIGNALS.

Aim:Generating different discrete time signals.

Equipments:



Software - MATLAB 7.1.0

Theory:

Procedure:

1. Click on the Matlab icon and open Mfile(finenewM-file)

2. Write the program and save it.3. Run the program .4. If any errors occurred in command window correct them and again run the

program.

5. Observe the result in command window and plots on figure window.


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Program:

clc;

clear all;

close all;

x=-pi:0.01:pi;

y=sin(x);z=cos(x);

k=square(x,20);

b=tripuls(x);

i=sawtooth(x);

c=rectpuls(x);

figure(1);

subplot(3,3,1)

stem(y);

subplot(3,3,2)

stem(z);

subplot(3,3,3)

stem(k);

subplot(3,3,4)

stem(b);

subplot(3,3,5)

stem(i);

subplot(3,3,6)

stem(c);

t=-10:0.1:10;

a=impulse(sys,t);

b=step(sys,t);

c=exp(sys,t);

figure(2)

subplot(2,2,1)

stem(a);

subplot(2,2,2)

stem(b);subplot(2,2,3)

stem(c);

Output:


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Result:

Precautions:

Files should not save with the numbers as starting.

Dont save the files with the two words separated by space.


Dont delete any file or folder without informing the system administrator or lab in-charge.

Viva-voce Questions:

Define Discrete time signal.

What are the different types of discrete time signals.

What is the command used for plotting of discrete time signal.

Compare discrete time and continuous time signal.

Explain about Matlab briefly.

Lab In-charge


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2. VERIFICATION OF SAMPLING THEOREM

Aim:To verify sampling theorem using MATLAB

Equipments:




Theory:

Procedure:


2. Write the program and save it.

3. Run the program .

4. If any errors occurred in command window correct them and again run theprogram.



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Program:

clc;

close all;

clear all;

t=-10:0.01:10;

T=8;fm=1/T;

x=sin(2*pi*fm*t);

fs1=1.2*fm;

fs2=2*fm;

fs3=8*fm;

n1=-4:1:4;

xn1=cos(2*pi*n1*fm/fs1);

subplot(221);

plot(t,x);

xlabel('time in seconds');

ylabel('x(t)');

title('continuous time signal');

subplot(222);

stem(n1,xn1);

hold on;

plot(n1,xn1);

xlabel('n');

ylabel('x(n)');

title('discrete time signal with fs2fm');

Output:


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Result:

Precautions:






Define Sampling theorem.

What is the condition of sampling theorem.

What is the disadvantage of the sampling theorem and what is the remedy for that.

How we can find the sampling frequency.

What are different toolboxes available in matlab.

Lab In-charge


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3. FFT AND IFFT

Aim:To verify Fast Fourier Transform.

Equipments:



Software - MATLAB 7.0

Theory:

Procedure:







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Program:

%fast fourier transform

clc;

clear all;

close all;n=input('enter the length of fft');

x=input('enter the sequence');

subplot(221);

title('i/p signal');

xlabel('n --->');

ylabel('x(n) -->');

grid;

stem(x);

%compute fft

disp('fourier transformed signal');

x1=abs(fft(x,n))

subplot(2,2,2);stem(x1);

xlabel('n --->');ylabel('x(n) -->');grid;

title('fft of i/p x(n) is:');

x2=fftshift(x1);

subplot(223);stem(x2);grid;

subplot(224);plot(x2);

% x=fftshift(abs(fft([ones(1,8),zeros(1,100)])));

% plot(x)

xlabel('Real axis --->');

ylabel('Imaginary axis -->');grid;

x3=ifft(x,n);

figure;

stem(x2);

xlabel('Real axis --->');

ylabel('Imaginary axis -->');grid;

Output:


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Result:

Precautions:






Define FFT.

Define IFFT.

What is the meaning of FFT and IFFT commands in Matlab.

Explain about the Fast Fourier transform.

Give the details of the commands used for finding FFT.

Lab In-charge


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4. TIME AND FREQUENCY RESPONSE OF LTI SYSTEMS

Aim:

To find time and frequency response of an LTI systems

Equipments:




Theory:

Procedure:

1. Click on the Mat lab icon and open Mfile(finenewM-file)2. Write the program and save it.

3. Run the program.4. If any errors occurred in command window correct them and again run the

program.



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Program:

Output:


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Result:

Precautions:


Dont save the files with the words separated by space.



charge.


What is an LTI system?

What are the characteristics of an LTI system?

What is meant by Frequency Response of LTI system?

What is meant by Time Response of the LTI system?

What are the toolboxes available in mat lab?

Lab In-charge


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5. LINEAR AND CIRCULAR CONVOLUTION THROUGH FFT

Aim:

To implement Linear and Circular convolution through FFT.

Equipments:




Theory:

Procedure:

1. Click on the Mat lab icon and open Mfile (finenewM-file)2. Write the program and save it.

3. Run the program.4. If any errors occurred in command window correct them and again run the

program.



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Program:% Program for circular convolution

clc;

clearall;

x1=input('enter the first sequence');

x2=input('enter the second sequence');

n=input('enter the no of points of the dft');

subplot(3,1,1);

stem(x1,'filled');

title('plot of first sequence');

subplot(3,1,2);stem(x2,'filled');

title('plot the second sequnce');

y1=fft(x1,n);

y2=fft(x2,n);

y3=y1.*y2;

y=ifft(y3,n);

disp('the circular convolution result is ......');

disp(y);

subplot(3,1,3);

stem(y,'filled');

title('plot of circularly convoluted sequence');

OR

clc;

clearall;

x1=input(enter the first sequence);

x2=input(enter the second sequence);

n=input(enter the no of points of the dft);

subplot(3,1,1);

stem(x1,filled);

title(plot of first sequence);

subplot(3,1,2);


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stem(x2,filled);

title(plot the second sequnce);

n1 = length(x1);

n2 = length(x2);

m = n1+n2-1; % Length of linear convolution

x = [x1 zeros(1,n2-1)]; % Padding of zeros to make it of

% length m

y = [x2 zeros(1,n1-1)];

x_fft = fft(x,m);

y_fft = fft(y,m);

dft_xy = x_fft.*y_fft;

y=ifft(dft_xy,m);

disp(the circular convolution result is ......);

disp(y);

subplot(3,1,3);

stem(y,filled);

title(plot of circularly convoluted sequence);

Output:


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Result:

Precautions:


Dont save the files with the words separated by space.




What is meant by linear Convolution?

What is meant by Circular Convolution?

What is the difference between Linear and Circular Convolution?

Commands used for Convolution using FFT.

What are the toolboxes available in mat lab?

Lab In-charge


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6. DESIGN OF FIR FILTERS(WINDOW DESIGN)

Aim:To Design and Implement FIR filters

Equipments:




Theory:

Procedure:

1. Click on the Mat lab icon and open Mfile(finenewM-file)


3. Run the program.




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Program:

%fir filter design (window techniques)

clc;

clear all;

close all;

rp=input('enter passband ripple');

rs=input('enter the stopband ripple');

fp=input('enter passband freq');

fs=input('enter stopband freq');

f=input('enter sampling freq ');

wp=2*fp/f;

ws=2*fs/f;

num=-20*log10(sqrt(rp*rs))-13;

dem=14.6*(fs-fp)/f;

n=ceil(num/dem);

n1=n+1;

if(rem(n,2)~=0)

n1=n;

n=n-1;

end

c=input('enter your choice of window function 1. rectangular 2. triangular 3.kaiser: \n ');

if(c==1)

y=rectwin(n1);

disp('Rectangular window filter response');

end

if (c==2)

y=triang(n1);

disp('Triangular window filter response');

end

if(c==3)

y=kaiser(n1);

disp('kaiser window filter response');

end

%LPF


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b=fir1(n,wp,y);

[h,o]=freqz(b,1,256);

m=20*log10(abs(h));

subplot(2,2,1);plot(o/pi,m);

title('LPF');

ylabel('Gain in dB-->');

xlabel('(a) Normalized frequency-->');

%HPF

b=fir1(n,wp,'high',y);

[h,o]=freqz(b,1,256);

m=20*log10(abs(h));


title('HPF');


xlabel('(b) Normalized frequency-->');

%BPF

wn=[wp ws];

b=fir1(n,wn,y);

[h,o]=freqz(b,1,256);

m=20*log10(abs(h));


title('BPF');


xlabel('(c) Normalized frequency-->');

%BSF

b=fir1(n,wn,'stop',y);

[h,o]=freqz(b,1,256);

m=20*log10(abs(h));


title('BSF');


xlabel('(d) Normalized frequency-->');


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Output:

Result:

Precautions:





charge.


What are advantages of FIR Filter?

What are different windows for fir filter?

What is the need of usage of windows?

What are different steps required to execute the DSP program in Mat lab.

What is the command used for FIR filter implementation.

Lab In-charge


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7. DESIGN OF IIR FILTERS (BUTTERWORTH&CHEBYCHEV)

Aim:To design and implementation of IIR (Butterworth &Chebychev) filters.

Equipments:




Theory:

Procedure:

1. Click on the Mat lab icon and open Mfile(finenewM-file)2. Write the program and save it.





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Program:

clc;

clear all;

close all;

warning off;

disp('enter the IIR filter design specifications');

rp=input('enter the passband ripple');

rs=input('enter the stopband ripple');

wp=input('enter the passband freq');

ws=input('enter the stopband freq');

fs=input('enter the sampling freq');

w1=2*wp/fs;w2=2*ws/fs;

[n,wn]=buttord(w1,w2,rp,rs,'s');

c=input('enter choice of filter 1. LPF 2. HPF \n ');

if(c==1)

disp('Frequency response of IIR LPF is:');

[b,a]=butter(n,wn,'low','s');

end

if(c==2)

disp('Frequency response of IIR HPF is:');

[b,a]=butter(n,wn,'high','s');

end

w=0:.01:pi;

[h,om]=freqs(b,a,w);

m=20*log10(abs(h));

an=angle(h);

figure,subplot(2,1,1);plot(om/pi,m);

title('magnitude response of IIR filter is:');

xlabel('(a) Normalized freq. -->');


subplot(2,1,2);plot(om/pi,an);

title('phase response of IIR filter is:');

xlabel('(b) Normalized freq. -->');

ylabel('Phase in radians-->');


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Output:

Result:

Precautions:





charge.


What are advantages of IIR Filter over FIR Filters?

What is the difference between Butterworth and Chebychev?

What is the Command used for Butterworth filter.

Explain about Mat lab.

What are the advantages of this Mat lab..

Lab In-charge


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Additional Experiments

Documents

VI-Sem-SP Lab-ECE