University of Mumbai 2004 B.E Electronics & Tele-Communication Engineering FILTER THEORY ( ) - Question Paper

FILTER THEORY (MAY 2004)
N. B.:
(1) Question No. one is compulsory.
(2) Answer any 4 ques. out of remaining 6 ques..
(3) Assumptions made should be clearly said.
1. (a) List properties of a Butterworth function. obtain network function for a 3rd order low pass
Butterworth filter and prove that this network function satisfies the properties listed. (10)
(b) Compare active and passive filter.
Derive expression for voltage transfer function for a general single amplifier active filter. (10)



2. (a) The high pass network shown in figure has a cutoff frequency of one rad/ sec for the specified
element values. (10)

(b) obtain the element values that will outcome when a frequency denormalization is made such that the put off frequency is changed to one kHz. obtain the voltage transfer Function for the frequency denormalized network obtained above.
3. (a) obtain the order needed for a normalized Butterworth function with stop band attenuation of at lowest 20 dB at stop band frequency of 1.8 rad/sec. If stop band attenuation is changed to 25 dB, what will be the change in order ? Draw its pole zero plot. (10)
(b)Write about "phase approximation". In which applications it is provided more importance ? Also, discuss
"ideal transmission". (10)
(b)
List properties of Chebyshev functions. Determine poles of a 2nd order low pass Chebyshev filter having a 3dB ripple in the passband. (10)
4. (a) describe sensitivity and discuss properties of relative sensitivity. (10)
(b) Realize (Synthesize) the subsequent function - (10)
Y(s)= Hs2 / { s3 + 2s2 + 2s + 1}
(a) Design a Band pass sallen and Key filter to meet the specifications f„ = 5kHz, Q = five and C = 10-8 F. Also draw its circuit diagram. How do we transform low pass Sallen and Key filter to high pass filter ? Hence design high pass filter to meet the specifications f„ = five kHz, Q=l/v2 , C=10-8 F. (10)
(b) Derive expressions for voltage transfer function of a high pass and band pass filter using state variable configuration. (10)
6. (a) How is leap frog structure developed ? Use this concept to realize a 5th order low pass filter. (10)
(b) Draw and discuss "Tow Thomas Biquadratic Filter" .Derive relation for voltage transfer function if it is used as a high pass filter. (10)
7. (a) Using switched capacitor circuits realize a noninverting integrator lossy integrator and summing
integrator. (10)
(b) List advantages of switched capacitor filters, Also show the effect of parasities on implementation
of switched capacitor filters. (10)

Earning:   Approval pending.