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  1. #1
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    Help me count how many full periods of x(t) is need for one period of sampled signal

    A 100Hz sinusoid x(t) is sampled at 240Hz. How many full periods of x(t) are required to obtain one period of the sampled signal??
    Plz sort this problem for me... I am confused!!

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  2. #2
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    sampling process

    Posted by Anonymous (it was posted wrongly in report system):
    see here the input signal x(t) having period=0.01sec is sampled with a sampling period 0.00416 sec .ur question is saying that n*0.01=0.00416 what is the value of n u r asking ......the value of n here getting is 0.416 since n is an integer in ur question so obviously n =0



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    sampling sinusoidal signals

    hey Klug,
    f= frequency of the sampled signal is=100/240=0.41667Hz
    therefore time period is,T=1/0.41667=2.4 sec (2.4 samples/cycle)
    that means 0.01xn=2.4 => n=240.
    that means 240 cycles of x(t) makes 1 complete period of the sampled signal.

    Whats ur take on this... plz reply.



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  4. #4
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    what is mean by sampling process of signals

    Hello!
    If I understood clearly you have:
    Fss = 100 Hz,
    Tss = 10ms
    Fd=240Hz,
    Fd = 4.166ms
    Tss = 2.4*Tss
    N = Fd/Fss = 2.4
    You have 2.4 samples per cycle of the SS.
    You have 2.4 periods of the sampling signal at one period of the sampled signal.
    Or you could not have “ p full periods” in “one period of the sampled signal” .
    If for example you have N=4 you will have 4 full periods of Fd in one period of Fss.


    May be that will help you at least when you sample sinusoidal and co sinusoidal signals:
    “A New Approach to Sampling Sinusoidal and Cosinusoidal Signals”, P T Petrov,
    http://www.ieindia.org/pdf/88/88ET104.pdf

    Also may be it will be useful to know:

    “Sampling of the Simplest Signals”, P T Petrov
    http://www.ieindia.org/pdf/89/89CP109.pdf

    Any feedback is welcomed
    BR
    Petre Petrov

    Added after 2 hours 50 minutes:

    In fact to have “ k full (integer) periods of the SS x(t)” Tss
    in one period of the sampling signal Td you should have:
    SSF N =1 or ½, or 1/3 , etc
    or
    N = 1/k
    or
    Tss = k*Td, k=1,2,3,4, …
    OK?



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