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Consider the information sequence 1101011011.Find the codeword corresponding to this sequence

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Here CRC polynomial is X4+X+1

so we can transform it to a string of binary word i.e 10010

[convert a polynomial functio to a binary word by making the places 1 which are valid for x and other places 0 starting from right hand side as place 0]

look here we have x4 so after counting from rhs ...2,1,0 like this we made the 4th one 1 ..again for X(means X1)  we made the second from rhs 1 and we have already 1 here so X0 means LSB is 1..

now polynomial is 10010 (5 bit)

so we have to append (5-1)=4 0's after the data word        [add n-1 0's if poly is n bit]

now the modified dataword is 11010110110000

now apply simple divide and then xor...as mentioned in book

edited

### g(x)=x4+x+1

here degree of polynomial  = 4 , So x4 will be used to augument the dataword

dataword = 1101011011

dataword polynomial = x9+x8+x6+x4+x+x+1

augumented dataword polynomial = (x9+x8+x6+x4+x+x+1).x4

augumented dataword polynomial =x13+x12+x10+x8+x+x5+x4

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