Umal-qura university

-------------------------TASK 08--------------------------

Write your own function to downsample a signal i.e. retain odd numbered samples of the original signal and discard the even‐numbered (downsampling by 2). The function must take a signal as input and return the downsampeled version of that signal. See Fig for example. Call this function from a matlab file. Verify your result by using the command “downsample”. Plot

the original signal, downsampled signal determined by your program, and downsampled signal obtained by the command downsample.

Fig. DownSampling

-------------------------TASK 09--------------------------

Write your own function to upsample a signal i.e. copy the 1st sample of original signal in the new signal and then place an extra sample of 0, copy the 2nd sample of original signal and then place a 0, and so on. See Fig for example. Call this function from a matlab file. Verify your result by using the command “upsample”. Plot the original signal, upsampled signal determined by your program, and upsampled signal obtained by the command upsample.

Fig. Upsampling

Lab # 5

OBJECTIVES OF THE LAB
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In this lab, we will cover the following topics:

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  Gain familiarity with Complex Numbers and plot them
  
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  Complex exponential signals
  
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  Real exponential signals
  

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1. COMPLEX NUMBERS

A complex number z is an ordered pair (x, y) of real numbers. Complex numbers can be represented in rectangular form as z = x + iy, which is the vector in two‐dimensional plane. The horizontal coordinate x is called the real part of z and can be represented as x = Re {z}, while the vertical coordinate y is called the imaginary