# HW11 - ECE 301 Homework#11 due date...

This preview shows pages 1–2. Sign up to view the full content.

http://cobweb.ecn.purdue.edu/ chihw/11ECE301F/11ECE301F.html Question 1: [Basic] Consider an AM-DSB signal y ( t ) = ( x ( t ) + 0 . 5)cos(3 πt ) is sent by a transmitter. 1. In what condition can we use asynchronous demodulation for the above system so that x ( t ) can be reconstructed perfectly? 2. Suppose the receiver receives y ( t ) as follows. What is the end result if we use asynchronous demodulation to construct the original signal x ( t ). -3 -2 -1 0 1 2 3 -1.5 -1 -0.5 0 0.5 1 1.5 y(t) t 3. The receiver realizes that the synchronous carrier at the receiver side is actually sin(3 πt ) instead of cos(3 πt ). Explain why it changes from cos(3 πt ) to sin(3 πt ). 4. How to construct x ( t ) from y ( t ) using synchronous demodulation. Please describe it by a diagram and explicitly specify all the frequencies involved. 5. What is the end result of using synchronous demodulation to reconstruct x ( t )? Question 2:

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 3

HW11 - ECE 301 Homework#11 due date...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online