ECE 381: Laboratory 7

Winter 2006

Bode Plot and Butterworth Filters

March 13

 

    

 

 

1.      Sketch Bode plots for the following transfer functions (4.9-1, Page 488) - (a), (b), (c)

2.      Using the lowest order possible, determine a system function H(s) with real-valued roots that matches the frequency in Fig.P4.9-3 (Page 489).

3.      Design a order-12 Butterworth lowpass filter with a cutoff frequency of 5000Hz. Locate and plot the filter's poles and zeros in the complex plane. Plot the corresponding magnitude response |HLP(jω)|.

4.      For each of the following cases, design the filter, plot the filter's poles and zeros in the complex s plane, and plot the decibel magnitude response 20 log10 |HLP(jω)|.

(a)    Design a sixth order analog lowpass filter with ωc=2*pi*3500.

(b)   Design a sixth order analog highpass filter with ωc=2*pi*3500.

(c)    Design a sixth order analog bandpass with a passband between 2 and 4 kHz.

(d)   Design a sixth order analog bandstop filter with a stopband between 2 and 4 kHz.