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Applications of theFourier TransformDr. Ali MuqaibelEE207

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Ideal Filters•  Transfer functions

•  Types !o"#pass$ %i&h#pass$'and#pass$ 'and#stop(band#re)ect*

• Ideal +lters are not

physically attainable.• !o"#pass +lter (!,F*

•  

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on#causal

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E/ample Ideal Filters

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Ideal !,F to eliminate noise

Ideal band#pass +lter

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1 !o"#,ass Filter

• 1onertin& the t"o equations into Frequencydomain

• eliminate

• De+ne $

•  

•   and

• 3hy cut frequency is called 4#d' or halfpo"er frequency5

• 6 $ 6

• 3hy all real system has phase delay  5

•  

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'y 8! in the t"oloops