PHASESENSITIVE DEMODULATION 2006200401 Taeeui Kim Phasesensitive Demodulation 10

PHASE-SENSITIVE DEMODULATION 2006200401 Tae-eui, Kim

Phase-sensitive Demodulation ; 10 Hz Sinusoid (Tx = 0. 1 s) ; High Freq. Signal (Tx = 0. 02 s) X(t) c(t) XO 1 0. 05 s -1 -XO 0. 1 s 0. 05 s 0. 1 s

Phase-sensitive Demodulation < MATLAB CODE > < MATLAB PLOT >

Phase-sensitive Demodulation < MATLAB CODE > < MATLAB PLOT >

Phase-sensitive Demodulation With Freq. 50 Hz < MATLAB CODE > < MATLAB PLOT >

Phase-sensitive Demodulation With Freq. 1000 Hz < MATLAB CODE > < MATLAB PLOT WITH HIGH MAGNITUDE >

Phase-sensitive Demodulation Given x(t) c(t) = y(t), find x(t) X LPF

Phase-sensitive Demodulation After LPF Phase Demodulation

Capacitive Sensor – Problem 9 (a) Metal plate Change of distance A B L ; Capacitive is dependent on changing distance between chest and metal plate

Capacitive Sensor – Problem 9 (b) A B

Capacitive Sensor – Problem 9 (b)

Capacitive Sensor – Problem 9 (c) X LPF

Capacitive Sensor – Problem 10 (a) Atmospheric pressure Air P 1 P 2 One is increased, The other is decreased At the same amount Chamber rigid A rigid B C X 1 Diaphragm X 2 A How to express by using equation from the sensor in order to analyze it is crucial B (when ) C Goal is to measure “ “

Capacitive Sensor – Problem 10 (a) A C AC (Capacitor) B D

Capacitive Sensor – Problem 10 (a)

Capacitive Sensor – Problem 10 (a) Constant x Something we would like to measure High Freq.

Capacitive Sensor – Problem 10 (b) Constant Unit less

Capacitive Sensor – Problem 10 (c)