Cork Institute of Technology
Bachelor of Engineering (Honours) in Electronic Engineering- Award
(NFQ Level 8)
Summer 2007
Applied Digital Signal Processing
(Time: 2 Hours)
Answer any four questions [each 25
marks]
Maximum available mark is 100.
Examiners: Dr. J. Connell
Prof. G. Hurley
Dr. S. Foley
Q1. (a) A Dual-Tone, Multi-Frequency signal consisting of a 852Hz and a 1477Hz
component is sampled at 8kHz. Discuss an analysis procedure for accurately
determining the spectral content of the digital signal. Assume that 40mSecs
maximum of data is available. [10 marks]
(b) A 30Hz, unity amplitude sinwave is sampled at 80Hz. Use a Goertzel cell to evaluate
the DFT at the frequency of interest. [15 marks]
Q2. (a) Compare the Periodogram and Bartlett methods for calculating the power spectrum
of a digital signal. [10 marks]
(b) The causal impulse response of an LTI system is given as
=
)(nh {1 -2 5}. The
causal input is given as
=
)(nx {2 -3}. Using the expressions for convolution and
correlation, show that )(*)()( lrlhlr xxyx
=
.
Indicate how this expression might be used in system identification. [15
marks]
