Overview of LectureIdeal Lowpass FilterIdeal Bandpass FilterIdeal Highpass FilterIdeal Notch FilterIdeal Delay FilterFilter ApplicationsI/O Impedance RestrictionsPositive Real Function TestStrictly Hurwitz TestReal Part TestExample Of Positive Real TestUltimate Positive Real TestParameter NormalizationNormalization . . . Cont’dNormalization ExampleShort Circuit Y-ParametersAlternative Y-Parameter ModelingBilateral Pi—Type ModelPlausible Design StrategySecond Order Lowpass FilterLowpass Filter Design . . . Cont’dLowpass Filter Design . . . Cont’dLowpass Filter Design . . . Cont’dHSPICE Verification Of DesignHSPICE Simulation ResultsOpen Circuit z-ParametersAlternative z-Parameter ModelingBilateral Tee-Type ModelFilter Design StrategyTransmission Parametersc-Parameter Network PropertiesComments On Transfer PropertiesCascade Network InterconnectionSeries And Shunt BranchesEE 541Class LectureWeeks 1 & 2Prof. John Choma, ProfessorDepartment of Electrical Engineering-ElectrophysicsUniversity of Southern CaliforniaUniversity Park; MC: 0271; PHE #604Los Angeles, California 90089-0271213-740-4692 [USC Office]213-740-7581 [USC Fax][email protected] Port Filter Network Models And AnalysisFall 2006 SemesterUSC Viterbi School of EngineeringEE 536 Fall 2005 Lecture #02/Choma2Overview of LectureOverview of Lecturez Fundamental Types Of Filters Frequency ResponseLowpassBandpassHighpassNotch Constant Delayz Common Filter Characteristics Maximum Voltage Or Current Transfer Maximum Power TransferLossless Branch ElementsInput And Output Port Impedance Matchingz Two Port Network Models y-Parameters z-Parameters c-ParametersUSC Viterbi School of EngineeringEE 536 Fall 2005 Lecture #02/Choma3z System Level Diagram And Responsez Basic Filter Properties Constant “Gain” Within Filter Passband: Zero “Gain” In Stopband: Designable Passband Gain Or Attenuation, |H(0)| Designable Bandwidth, Bz Positive Real Impedance Requirement (All Filters)+−ZsZlVsLowpassFilterZinZoutVo|H(j )|ω|H(0)|ωB0osV(jω)H(jω)V(jω)H(jω)H(j0),0ω B=≤<H(jω)0,ω B=>inRe Z (jω)0,0ω≥≤<∞outRe Z (jω)0,0ω≥≤<∞Ideal Lowpass FilterIdeal Lowpass FilterUSC Viterbi School of EngineeringEE 536 Fall 2005 Lecture #02/Choma4z System Level Diagram And Responsez Basic Filter Properties Constant “Gain” Within Filter Passband: Zero “Gain” In Low And High Frequency Stopbands Designable Passband Gain Or Attenuation, |H(jωo)| Designable Bandwidth, B, And Center Or Tuned Frequency, ωo Resultantly Designable Quality Factor:+−ZsZlVsBandpassFilterZinZoutVo|H(j )|ω|H(j )|ωoωωo+B/20ωo−B/2BωoosV(jω)H(jω)V(jω)oo oBBH(jω)H(jω ), ωωω22=−<<+oωQBIdeal Bandpass FilterIdeal Bandpass FilterUSC Viterbi School of EngineeringEE 536 Fall 2005 Lecture #02/Choma5z System Level Diagram And Responsez Basic Filter Properties Constant “Gain” Within Filter Passband: Zero “Gain” In Stopband: Designable Passband Gain Or Attenuation, |H(j∞)| Designable Cutoff Frequency, ωcz Positive Real I/O Impedance Requirement Remains For This And All Other Passive Filters+−ZsZlVsHighpassFilterZinZoutVo|H(j )|ω|H(j )|∞ω0ωcosV(jω)H(jω)V(jω)cH(jω)H(j), ω > ω=∞cH(jω)0,ω < ω=Ideal Highpass FilterIdeal Highpass FilterUSC Viterbi School of EngineeringEE 536 Fall 2005 Lecture #02/Choma6z System Level Diagram And Responsez Basic Filter Properties Constant Attenuation Within Filter Stopband: Constant “Gain” In Low And High Frequency Passbands Designable Stopband Attenuation Factor, |H(jωo)| / |H(0)| Designable Stopband Bandwidth, B, And Notch Frequency, ωo Resultantly Designable Quality Factor:+−ZsZlVsNotchFilterZinZoutVo|H(j )|ω|H(j )|ωoωωo+B/20ωo−B/2Bωo|H(0)|osV(jω)H(jω)V(jω)oo oBBH(jω)H(jω ), ω < ω < ω22=−+oωQBIdeal Notch FilterIdeal Notch FilterUSC Viterbi School of EngineeringEE 536 Fall 2005 Lecture #02/Choma7z System Level Diagram And Responsez Filter Delivers Linear I/O Phase Response Significance Is Constant Time Delay Of Steady State Sinusoids Cursory Analysis: Note Time DelayIn Steady StateIs FrequencyIndependent()()[]()ssmossmosmosmdV(jω)V ωtV(jω)H(jω)V (jω)H(jω)V ωtV(jω)H(jω)V ωt φ(ω)V(jω)H(jω)V t Tcoscoscoscos ω===+=−+−ZsZlVsDelayFilterZinZoutVoφω()ω0φω−ω() = Tdjφ(ω)osV(jω)H(jω)H(jω)V(jω)e=Ideal Delay FilterIdeal Delay FilterUSC Viterbi School of EngineeringEE 536 Fall 2005 Lecture #02/Choma8Filter ApplicationsFilter Applicationsz Lowpass Filter Mitigate Interference From High Frequency Signals Integrate Applied Input Signal Serve As Prototype For Other Filter Typesz Bandpass Filter Selective Signal Processing Over Stipulated Passband Tuning In Communication Receiversz Highpass Filter Mitigate Interference From Low Frequency Signals Differentiate Applied Input Signalz Notch Filter Mitigate In Band Signal Interferencez Delay Filter Incur Nominally Constant Time Delay In Sinusoidal Steady StateUSC Viterbi School of EngineeringEE 536 Fall 2005 Lecture #02/Choma9+−ZsZlVsLinearPassive FilterZinZoutVoz Positive Real Impedances Required For Stability Required For PhysicallyPossible Realization Mathematical Constraintsz Signal Processing Voltage Transfer |Zin(jω)| >> |Zs(jω)| ; |Zl(jω)| >> |Zout(jω)| Current Transfer |Zin(jω)| << |Zs(jω)| ; |Zl(jω)| << |Zout(jω)| Maximum Power Transfer Zin(jω) = Zs(–jω) ; Zl(jω) = Zout(–jω)Complex Conjugate Impedance Matching At I/O Network PortsMaximum Power Transfer Critical In Radio Frequency (RF) Applications Were Signal Power Levels Are AnemicLossless Network Desirable To Mitigate Any Signal Power Loss In FilterinoutZ(jω) 0, for all ω 0Z(jω) 0, for all ω 0ReRe≥≥≥≥I/O Impedance RestrictionsI/O Impedance RestrictionsUSC Viterbi School of EngineeringEE 536 Fall 2005 Lecture #02/Choma10eoeoN (s) + N (s)N(s)Z(s) K KD(s) D (s) + D (s)==z Generalized Impedance Function (Constant K > 0)z Definitions Ne(s) / No(s) Even/Odd Polynomial Components Of N(s) De(s) / Do(s) Even/Odd Polynomial Components Of D(s)z Positive Real (PR) Tests (3-Step
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