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System Noise and Synchronous Detection
System Noise and Synchronous Detection 97
(a) (b)
Signal Signal
Ref. +1 -1 +1 -1 +1 -1 Ref. -1 +1 -1 +1 -1 +1
Product Time Product
(c) (d)
Signal Signal
Ref. +1 +1 +1 Ref. +1 +1 +1
-1 -1 -1 -1 -1 -1
Product Product
Time
(e)
Signal
Ref. +1 +1 +1
-1 -1 -1
Product Time
Figure 5.3 Demodulator waveforms for various relative alignment phases. (a) in phase, (b)
antiphase, (c) in “quadrature,” (d) zero response to a DC signal, (e) DC-response removed, AC
detected.
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