L6_2

# Which have an error dene p rowi to be the parity of

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Unformatted text preview: el each data bit with subscript giving its row and column: the ﬁrst bit would be d11 , the last bit drc . See Figure 6-3. 10 LECTURE 6. COPING WITH BIT ERRORS d11 d21 p col(M, 1) d12 d22 p col(M, 2) d13 d23 p col(M, 3) p row(M, 1) p row(M, 2) d14 d24 p col(M, 4) Figure 6-3: A 2 × 4 arrangement for an 8-bit message with row and column parity. 0 1 1 1 1 0 1 0 1 (a) 0 1 1 0 1 1 0 1 0 0 0 0 1 1 1 0 0 1 1 0 1 1 1 1 0 (b) 1 1 0 1 0 0 1 1 (c) Figure 6-4: Example received 8-bit messages. Which have an error? Deﬁne p row(i) to be the parity of all the bits in row i of the array and let R be all the row parity bits collected into a sequence: R = [p row(1), p row(2), . . . , p row(r)] Similarly, deﬁne p col(j ) to be the parity of all the bits in column j of the array and let C be the all the column parity bits collected into a sequence: C = [p col(1), p col(2), . . . , p col(c)] Figure 6-3 shows what we have in mind when k = 8. Let w = M · R · C , i.e., the transmitted code word consists of the original message M , followed by the row parity bits R in row order, followed by the colu...
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## This document was uploaded on 02/26/2014 for the course CS 6.02 at MIT.

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