Product Description

1) SSB  Demodulation:  Consider  the  message  waveform

  

 

and  the   SSB  modulated  signal m_SSB-AM (T).You  can  use  here  whatever  SSB  method  you  like  to   use,  such  as  phase  method  or  Hilbert  transform  method.    First  obtain m_SSB-AM (T) and demodulate  it  to  get m_DEMOD (T).

Now  compare m_DEMOD(T) and m(t) and illustrate the effect  of  local  oscillator  phase  errors,Ø, and m_DEMOD(T).

show the distortions for Ø=Π/20 ,Ø=Π/6 and Ø=Π/2 ,by plotting the frequency spectra and waveforms of m_DEMOD 

(T)and m(t) on  separate  graphs.

2) Envelope  detection:  Demodulate  the  signal  s(t)=A_c ⌈1+km(t)⌉cos(2Πƒ_ct) ,  where  f_c  =250  Hz,  and  k  =  0.85.    Plot  the  modulated  signal,  the  message  and  its  demodulated   version.  Try  filters  with  bandwidth  of  300  Hz  and  100  Hz.

3) Frequency  modulation:  Let  m(t)  modulate  a  carrier cos(2Πƒ_c T) where f_c =200  Hz  and   frequency  deviation k_f =50  in  the  expression s(t)=A_c cos(2Πf_ct+2Π k_f ∫m(s)ds. plot the  waveforms  and  spectra  of  the  message  signal  and  the  modulated  signal

4) Frequency  modulation:  Let

 The  message  m(t)  modulates  a  carrier cos (2Πf_ct) where f_c=250 Hz freqeuncy deviation k_f=100 plot the  modulated  signal  in  the  time  and  frequency  domain.  Also  plot  the  waveforms  of  the   modulating  signal  and  its  demodulated  version  and  compare