Page 26 - eBOOK FUNDAMENTAL OF TELECOMMUNICATION NETWORK
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S T E P 1
Sampling
Nyquist Theorem:
Sampling frequency; fs >= 2 * fmax
Analog signal for voice are 0 – 4000Hz, the highest
frequency is 4000Hz.
Hence, the sampling frequency (fs) adopted for PCM
is
2 x 4000 Hz = 8000Hz
which results in taking samples every 125 us
So, the sampling process will occur in every 125 µs.
The output of sampling is still in an analog form
called pulse amplitude modulation (PAM).
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