Digital Signal Processing DSP Problem 6. Refer the following figures A, B and C.
ID: 2248473 • Letter: D
Question
Digital Signal Processing
DSP Problem
6. Refer the following figures A, B and C. Figure A shows the digital signal. Figure B and C display the spectral plots of the digital signal obtained from the different window functions, respectively. Each spectrum is calculated using the data window having 256 data points as shown in Figure A and the sampling frequency of 8000 Hz. Answer the following questions: (10 points) 20 0 20 0 0.002 0.004 0.006 0.008 0.01 0.012 0.014 0.016 Figure A time (sec.) 2 0 1000 2000 3000 4000 5000 6000 7000 8000 Figure B frequency (Hz) 2 0 1000 2000 3000 4000 5000 6000 7000 8000 Figure C frequency (Hz) a. According to Figure B or Figure C, list frequencies of the digital signal excluding the high spectral frequencies b. Determine the frequency resolution. c. What is the highest frequency value that the digital signal has? d. Which frequency dominates the digital signal?Explanation / Answer
a) When a signal is sampled the frequency spectrum will become periodic. And frequency spectrum ia an even function. So. According to fig b. And C 500 Hz , 1000hz and 1500 Hz signals are present in the signals.
B) frequency resolution is the distance in Hz between two adjecent data points in DFT. So it can be observed from the figure the adjacent data points are separated by 500hz so frequency resolution is 500 Hz.
C) from the figure it can conclude 1500hz signal is the maximum frequency component present in the signal as frequency spectrum is even and periodic with sampling frequency.
D) if we observe 1000hz signal is having more magnitude so 1000hz frequency component is dominant