ELEC 412 - Lecture 18 1

ELEC 412

RF & Microwave Engineering

Fall 2004

Lecture 18

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Balanced Single Stub MatchingBecause of the parallel connection, the total admittance of the

stubs will be double that of each leg, that is, Ybal = 2Ystub. A single unbalanced stub of length d can be converted into an equivalent balanced stub of length db by requiring that the two configurations provide the same admittance.

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Balanced Single Stub Matching

stubopenβd

aπ

λdβdβd

stubshortedβd

aπ

λdβdβd

bb

bb

2

tantan

2tantan2

2

cotcot

2cotcot2

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Unbalanced Single Stub Matching

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Balanced Single Stub Matching

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