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  1. #1
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    symbol error and bit error

    hi
    can you determine how symbol and bir error rates are related.and what this relation depends on.

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  2. #2
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    Re: how symbol and bit error prob. are related.

    hi

    P_M : symbol error prob.
    P_b : bit error prob.
    k : number of bit per each symbol

    P_M= [2^(k-1)/(2^k-1)]*P_b

    you must read this book
    " digital communication" by proakis(chapter five)



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  3. #3
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    Re: how symbol and bit error prob. are related.

    [size=18]if you are using grey code in coding therefore
    ser= symbol error rate
    ber= bit error rate
    k=number of bits per sybol = log (base 2) M
    where M is the M ary you are using
    therefore ber=ser/k[/size]



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  4. #4
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    how symbol and bit error prob. are related.

    If gray coding is assumed, the bit error rate is 1/log2(M) of symbol rate where M is the modulation order (for example, M=4 for 4PSK).

    However, gray coding is not always applicable to all modulation constellation. In such case, some approxiamate can be found in Proakis's book.



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