Fall Semester 2012-2013
Midterm Exam I Questions
Midterm Exam I Questions (EE 685)
Exercises/Problems
Exercises/Problems
Exam Grades
Computer Experiments
The computer experiments will be processed on the sound signal;
bird.wav and the electrocardiogram (ECG) signal;
ecg.txt (sampling frequency = 1000 Hz) and the black and wihite image;
barbara.png. The computational environment is Matlab; use Matlab to do the excercices.
- Read and plot the sound and ECG file.
- Obtain the envelope of the sound signal with Hilbert transform.
- Find the energy spectrum of the sound and ECG signal.
- Segment the both signals using 50% overlaping windows.
- For each segment compute the average power (of both signals). Plot the power versus window (segment) index.
- For each segment compute the dominant frequency (of both signals). Plot the frequency versus window (segment) index.
- Locate R-peaks in the ECG signal.
- Read and display the image.
- Obtain negative of the image.
- Find difference of the image in both x and y direction to detect edges; convolve first rows (columns) with difference operator; [1, -1], and then convolve columns (rows) with the difference operator; [1; -1].
- Design a half band low pass FIR filter with order 11 by using Fourier series method. Use Hamming window for windowing.
- Generate signal; x(n) = cos(pi/8*n) + cos(7*pi/8*n).
- Using the designed low pass filter, filter x(n). What do you get?
