1. ELEC 412 - Lecture 141 ELEC 412 RF & Microwave Engineering Fall 2004 Lecture 14

2. ELEC 412 - Lecture 142 Lumped Parameter Band-Pass Filter Design Design an N=3 band-pass maximally flat (Butterworth) filter with a center frequency of 900 MHz. The Bandwidth of the filter is 20% ; That is, BW = (0.20)(900 MHz) = 1.8 MHz or  0.9 MHz. From the Maximally Flat Low Pass Prototype Table 5-2, g 0 = g 4 = 1, g 1 = g 3 = 1, g 2 = 2

3. ELEC 412 - Lecture 143 Low Pass Prototype Filter Where the normalized center frequency is  c = 1,  L = 1.1(2  ·900 MHz), and  U = 0.9(2  ·900 MHz) So that  U -  L = 1.13Grad/s and

4. ELEC 412 - Lecture 144 Finding the Filter Components

5. ELEC 412 - Lecture 145 Filter Simulation with Ansoft Designer

6. ELEC 412 - Lecture 146 Filter Simulation with Ansoft Designer

7. ELEC 412 - Lecture 147 Some Observations On The Results Values of components are unreasonable Some other method for implementing the filter design goals must be found Solution: Use distributed filters using waveguides Richardson Transforms and Kuroda’s Identities

8. ELEC 412 - Lecture 148 Richards Transformation: Lumped to Distributed Circuit Design

9. ELEC 412 - Lecture 149 Kuroda Transforms