lec22

lec22 - (which are typically small) and Conduction losses c...

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon
EE 3113 INTRODUCTION TO RF CIRCUIT DESIGN Lecture Notes for A-term 2003 LECTURE 22 Prof. R. Ludwig Department of Electrical and Computer Engineering Worcester Polytechnic Institute Worcester, MA 01609 copyright © 2003, R. Ludwig Copyright, 1998 © R. Ludwig
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
EE3113_L22 2 Microstrip line Matching Networks • Most commonly used in RF circuits • Can be used up to approximately 20 GHz (for TEM modes) • Microstrip lines require typically 6 parameters – dielectric constant ε r – PCB board height h , strip width w , thickness t – resistivity ρ and loss tangent d
Background image of page 2
EE3113_L22 3 Key parameter designations ε r , d w t h ρ ??? 0 = + + = C j G L j R Z ω Don’t use:
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
EE3113_L22 4 Please keep in mind, there are two issues A) phase velocity and B) characteristic impedance: eff r p c c v ε → = 1 / ) 4 1 8 ln( 60 0 0 + = → h w h w w h Z Z eff 1 / ) 444 . 1 / ln( 667 . 0 393 . 1 / / 120 60 0 + + + = h w h w h w Z eff eff π Numerical evaluation (Textbook, pages 64 - 69): Z 0 ( ε r )=F 1 (w/h) and ε eff ( ε r )=F 2 (w/h)
Background image of page 4
EE3113_L22 5 Microstrip lines have two sources of losses z c d e Z V z P ) ( 2 0 2 | | 2 1 ) ( α + + + = Dielectric losses α d
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 6
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 8
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: (which are typically small) and Conduction losses c (which can be significant) Depending on frequency, one may have to deal with radiation losses as well! EE3113_L22 6 Classes of amplifier operation I C V BE Cut-off region Quiescent point V * Linear region Ideal transfer function Input waveform Output waveform I C V BE Quiescent point =180 o I C V BE Quiescent point I C V BE Quiescent point Class A Class B Class AB Class C EE3113_L22 7 Efficiency of an amplifier % 100 S RF P P Power Source Power RF = = I L I 2 3 Current through load I S I Q + I 2 3 I Q /2 Current from the power supply EE3113_L22 8 )] 2 / sin( 2 ) 2 / cos( [ 2 sin = Conduction angle, o Efficiency , % =78.5% =180 o Class B Class A Class AB Class C...
View Full Document

This note was uploaded on 01/31/2012 for the course EE 4002 taught by Professor Scalzo during the Fall '06 term at LSU.

Page1 / 8

lec22 - (which are typically small) and Conduction losses c...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online