Abstract
Two-stage stepped-impedance resonator (SIR) filters are designed to have a wide upper stopband. Two transmission zeros are also created near the passband to form a quasi-elliptic response. For a 20-dB rejection level, with properly designed SIR geometry and tapped-line structure, the leading three spurious resonances of the SIR are suppressed by transmission zeros and respective unmatched singly loaded Q (Qsi) values. Measured results illustrate that stopbands up to 8.4 and 5.3 times the design frequency can be achieved for rejection levels of 20 and 30 dB, respectively.
Original language | English |
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Pages (from-to) | 34-36 |
Number of pages | 3 |
Journal | IEEE Microwave and Wireless Components Letters |
Volume | 17 |
Issue number | 1 |
DOIs | |
State | Published - 01 2007 |
Externally published | Yes |
Keywords
- Microstrip filter
- Rejection
- Stepped-impedance resonator (SIR)
- Tapped-line
- Upper stopband