Today's Agenda
     Analog and Digital Signals.
     Periodic and Non-periodic signals.
     Time domain and Frequency domain 
       representation.
     Fourier Analysis
     Nyquest theorem.
                                          M.Sc. in IT - Year 1 Semester II - 2012
    Session Outcomes
     At the end of this session you will  
       have a broad understanding of 
       Analog and Digital signals, Fourier 
       Analysis and Nyquest theorem.
                                          M.Sc. in IT - Year 1 Semester II - 2012
    Data and Signals
    
     Data is in memory.
    
     It is converted in to Signals When transmitting 
    
     Need a transmission media to transmit signals. 
    
     Signals can be divided as,
    ▪ Analog Signals, Digital Signals
    ▪ Periodic Signals, Non Periodic Signals
        
                                          M.Sc. in IT - Year 1 Semester II - 2012
    Analog Signals and Digital 
    Signals
     Analog signals are continuous  and 
       has infinitely many levels of intensity 
       over a period of time.
     Digital signals are discrete and has 
       limited number of levels of intensity 
       over a period of time.
                                          M.Sc. in IT - Year 1 Semester II - 2012
     Periodic and Non periodic 
     Signals
      Can be analog or digital.
      Periodic signals – has a pattern 
         which repeats over identical periods. 
         (Cycle)
      Practically we do not have periodic 
         signals.
      Non periodic signals – changes 
                   Periodic analog                 Non Periodic analog 
                   signal                          signal
         without exhibiting a pattern or cycle 
         that repeats over time.
                                                    M.Sc. in IT - Year 1 Semester II - 2012