Elec 9305: Digital Signal Processing

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ELEC 9305: Digital Signal Processing

Lab#2 Report

Design and Testing of FIR Low-Pass Filter

Tailin Wang 460071145

B．Design

Procedure

1. N

T.W. = 3.0 kHz-2.5 kHz = 0.5 kHz

Rectangular: 109.2 (0.91*fs/T.W.)

Hamming: 412.8 (3.44*fs/T.W.)

Cutoff frequency: 2.75 kHz = (fs1+fp1)/2

4.

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Figure 1

5. 100Hz

[pic 3][pic 4]

 Hamming                  Rectangular

1000Hz

[pic 5][pic 6]

Hamming             Rectangular

2000Hz

[pic 7][pic 8]

Hamming          Rectangular

2500Hz

[pic 9][pic 10]

Hamming                Rectangular

2700Hz

[pic 11][pic 12]

Hamming                        Rectangular

2800Hz

[pic 13][pic 14]

Hamming                 Rectangular

3000Hz

[pic 15][pic 16]

Hamming          Rectangular

C. Real time testing

Demonstration Exercise 1: when frequency is from 1 kHz to 15 kHz, tones are getting shaper and shaper; when frequency is over 15 kHz, we cannot hear the tones.

FIR Filter Measurement:

Measurement for FIR low pass filter designed with Rectangular window