DspEdu 2.1 - Educational Software in DSP

  Covers Linear Convolution of Two Finite Duration Sequences , Circular Convolution of Two Sequences,Linear Convolution from Circular Convolution , FFT and Sampling of Fourier Transforms , Spectral Analysis of Periodic Continuous Waveforms by FFT , FIR Filter Design by Windowing , IIR Filter Design by Analog to Discrete Transformation and Discrete-Time Transfer Function Pole-Zero Analysis.

  This is a Perl/Tk GUI program for Windows Platform to help Students of Digital Signal Processing at Engineering Undergraduate level in learning introductory DSP and experimenting with basic concepts of DSP. Course Instructors will also find the program of help in enhancing the effectiveness of their lectures by using the plot displays from this program. There are six modules under this program at present. More modules will be added in future and these modules will also undergo revision.

  All the components of this program are written in Perl programming language and Tk GUI toolkit. The programs were developed by using ActiveState Perl for Windows (Perl 5.6.1 build , Binary Build 6.29) and perl modules from ActiveState and CPAN.

 
The Modules in DspEdu 2.1
 

1. 'CONVOLVE' Module   

This module helps the student of DSP to study Linear Convolution of Finite Duration Sequences and to examine the relationship between Linear Convolution and Circular Convolution of such sequences. There are 10 examples coded in the program. In addition, user can create, edit and save sequences. The Convolution results can be saved into text files.The plots can be saved in Postscript format. The process of linear and circular convolution is shown graphically and the evolution of result points is shown as the Scanning Function moves over the input sequence. 

2. 'FFT' Module   

This module assists the student of DSP in his study of the DFT of Finite Duration Sequences and to examine the relationship between spectral sampling and time-domain aliasing in such sequences. There are 10 examples coded in the program. In addition, user can create, edit and save sequences as project files which can be subsequently loaded into the module. The FFT computation results can be saved into text files and the plots can be saved in Postscript format.

This module also allows the user to calculate and display samples of Fourier Transform (sample number less than the length of sequence) of finite duration sequences and to examine the relationship between inverse DFT of such samples and the original data sequence. A comparison of Fourier Transforms of the original sequence and the aliased sequence also can be performed.

3. 'SPECTRA' Module   

This module covers the application of FFT calculations for Spectral Analysis of periodic continuous-time waveforms.Resolution , Picket Fence Effect , Spectral Leakage , Effect of Synchronous Sampling , Effect of Window Shape etc can be demonstrated. The program supports six windowing techniques including Kaiser window. The user can create, edit and save sampled waveforms. The calculated spectra can be saved into a text file and the plots can be saved in Postscript format.

4. 'FIRWIN' Module   

This module deals with the FIR Filter Design by Windowing Technique. Low Pass , High Pass , Band Pass and Notch Filters are covered. Six Windows including Kaiser Window are included. The user can create, edit and save FIR Filter designs and the saved designs can be loaded into the program subsequently. The Frequency response computation results and the Window Fourier Transform can be saved into text files and the plots can be saved in Postscript format.

5. 'IIRFILT' Module   

This module deals with the IIR Filter Design by Bilinear Transformation. Low Pass , High Pass , Band Pass and Notch Filters are covered. Three types of approximation functions - Butterworth , Chebyshev , Inverse Chebyshev - are included. The user can create, edit and save IIR Filter designs and the saved designs can be loaded into the program subsequently. The Frequency response  computation results and the design output can be saved into text files. The plots can be saved into Postscript files.

The filter transfer function arrived at in this module can be saved in a format suitable for loading into the DTFA module for more detailed analysis of frequency response - for example, to examine how the different second order sections in a Butterworth or Chebyshev filter contribute to the overall frequency response.

6. 'DTFA' Module   

This module covers the Frequency Response and Time Domain Response of Discrete-Time Transfer Functions. The user can enter the poles and zeros of the system interactively and save the project file. The Frequency Response computation displays the graphical interpretation in the Pole-Zero diagram.

Animation shows the variation of pole distances and zero distances in the pole-zero plot as the frequency response evolves in the upper semicircle of unit circle in the z-domain.

Download Evaluation Version of DspEdu 2.1

The setup file installs the program files , default project directories and the required Perl files and modules under C:\DspEdu by default.DspEdu uses the Perl which gets loaded under its installation directory even if the target system has Perl installed in it. However , it does not affect the existing Perl installation , if any. Neither does it modify any system settings or system files like autoexec.bat, system.ini, win.ini etc.

The evaluation version allows 15 sessions for each module and each session is time-limited to 10 minutes. There are no feature-limits in the evaluation version.
 

The Main Control Panel of the program has a 'Register DspEdu' button. Clicking on this brings up a dialog box. Enter the Serial Number and the corresponding Key in the entry boxes provided for the purpose and click on the OK button to register the program. Successful registration creates a license file in the installation directory.

You can obtain the Serial Number and Registration key from RegSoft.

Student users from India can contact me over email for other payment options in INR.

I am Suresh Kumar K.S. I teach in the Department of Electrical Engineering at National Institute of Technology Calicut, Kerala State , India.
I wrote this program when I was teaching a course on basic DSP to final year Undergraduate students of Electrical and Electronics discipline last year.
And I learnt a little bit of Perl for writing CGI Scripts , programs for site indexing and site search , programs for web site management etc in connection with my earlier responsibility of building a Digital Library (called Nalanda Digital Library) at my Institute.

Suresh Kumar K.S
Assistant Professor in Electrical Engineering
National Institute of Technology Calicut,
Calicut-673601,Kerala,India

email - sureshks (at) nitc (dot) ac (dot) in

Home Page - My Official Home Page

Phone - 91-0495-2286334