Specifications

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安捷倫科技高頻元件量測研討會
Feb.23, 2006
Pulsed S-parameter Measurement Modes
Narrowband/asynchronous acquisition
• Extract central spectral component only; measurement appears CW
• Data acquisition is not synchronized with incoming pulses (pulse trigger not required)
• Sometimes called “high PRF” since normally, PRF >> IF bandwidth
•“Spectral nulling" technique achieves wider bandwidths and faster measurements
• No lower limit to pulse width, but dynamic range is function of duty cycle
IF filter
IF filter
Time domain
Frequency domain
D/R degradation = 20*log[duty cycle]
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安捷倫科技高頻元件量測研討會
Feb.23, 2006
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Filtered Output Using Spectral Nulling
Pulsed spectrum
Output
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Digital filter (with nulls aligned with PRF)
• With “custom” filters, number of filter sections (M) can be
chosen to align filter nulls with pulsed spectral components
• With spectral nulling, reject unwanted spectral components with
much higher IF bandwidths compared to using standard IF filters
• Result: faster measurement speeds!