Pulse-Amplitude Modulation minimum clock frequency

Thread Starter

skyline977

Joined Jan 14, 2021
29
Hi,
Below is the question and answer:
d.png
Source:
Study Guide for Fundamentals of Engineering (FE) Electrical & Computer CBT Exam- Third Edition By Wasim Asghar, ISBN:9798670880909

However, as per the below book it's given as :
2021-01-24.png
Source:
FE Reference Handbook 10.0.1, by NCEES, ISBN 978-1-947801-11-0

It clearly says that the signal can be generated by the sampling frequency i.e. the correct answer is 15 kHz.
Am I right?
 

andrewmm

Joined Feb 25, 2011
1,476
Hi,
Below is the question and answer:
View attachment 228565
Source:
Study Guide for Fundamentals of Engineering (FE) Electrical & Computer CBT Exam- Third Edition By Wasim Asghar, ISBN:9798670880909

However, as per the below book it's given as :
View attachment 228566
Source:
FE Reference Handbook 10.0.1, by NCEES, ISBN 978-1-947801-11-0

It clearly says that the signal can be generated by the sampling frequency i.e. the correct answer is 15 kHz.
Am I right?
As highlighted by @crutschow

The main thing to consider here, is the nyquest theory,

If you think of a sine wave of 15 Khz,
then to have at least one sample on the +ve and the -ve part of the waveform, then the minimum is two samples per cycle,
i.e 30 KHz.

This works for sampling and generating,

Try drawing a sine wave with less than 2 samples per period.

Now in practise you would have many more samples per cycle,


Yes a PAM can be made by taking samples at a frequency of a signal,
but that sampling frequency has to as a minimum meet Nyquest.
 
Top