课程设计2 - 百度文库 ر

ͼ3.1.2 Results Browser

Ϊеǽ棬ڡac-acļУac-acļкұߴʾڡResults BrowserΪĽṩ˼õĺͼ4.1.3

ͼ3.1.3 Results Browser

ͼ˵еĺ£ Magķֵ Phaseķ

Wphaseķǣһ0-360ʾ Realȡʵ Imagȥ鲿

dB10ԷС10logn dB20ԷС20logn

Ϊ뽻ѹ1VˡVoutĵѹֵŴ档

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Ϊ˹۲ƵԣҪ˵ĵѹķֵͨMagԡVoutȡֵԤȻͿԽôõķWaveformй۲졣

ұߴѡСVoutȻҼڵIJ˵ѡNew WinһµġWaveformʾŴķƵԡͼ3.1.4

ͼ4.1.4 ķƵ

ŴķƵԣֱʾֵ⣬һʾֵdBߣԷֵ20logn仯ͼ3.1.5

ͼ3.1.5 ֵdB20

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ŴƵԣڡResults BrowserѡphaseԽԤõͨAppendƵӵԭеķƵУͼ31.6

ͼ3.1.6 ɫƵɫƵ

ڶ ŴĴ

ͼ3.2.1 ·ͼ

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˵ĴҪָŴСźŴõĶ3dB͵λ浥

һ3dB

壺Av(?0)=20lgAv(0)-3dB

ȹ۲ķƵߣ3dBĶõ3dBڡWaveformУƵƵߵĵƵ֣ݼmӱǩǵĺ꣨1.212Hz37.24dBŵݼvлֱͣһֱֱߣֱϷһɫĵǣͨ϶ǣƶֱꡣ

ͼ3.2.1.1ֱŴƵ߽꣨7.9456MHz34.24dBڲͼϽǸŴֱƶʵʱı䡣Ϊ34.24dBʱźŵƵΪ7.9456MHz˿ԽΪ3dBΪ7.9456MHz

ͼ3.2.1.1 ķƵ

ȷ3dBķʹáCalculatorСbandwidth ڡResults Browserеġac-acѡVoutҼѡCalculator͵CalculatorУѡbandwidthͼ3.2.1.2

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