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Suppose we want an error-correcting code that will allow all single-bit errors to be corrected for memory words of length 10.

a)How many parity bits are necessary?
b)Assuming we are using the Hamming algorithm presented in this chapter to design our error-correcting code, find the code word to represent the 10-bit information word: 1001100110.

User Yotam Omer
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Final answer:

To correct single-bit errors in 10-bit memory words, 4 parity bits are necessary according to the Hamming code algorithm. Using this algorithm, the code word for the 10-bit information word '1001100110' includes these parity bits, and the exact code word is determined by the Hamming parity calculation process.

Step-by-step explanation:

Calculating the Number of Parity Bits Necessary:

For an error-correcting code that allows all single-bit errors to be corrected in memory words of length 10, we first need to determine the number of parity bits necessary. The Hamming algorithm can be used to do this. The formula to calculate the number of parity bits (p) needed for a specific length of the data bits (d) is:

2^p >= d + p + 1

For d=10, we increase the value of p until the inequality holds. Solving, we find that p=4 parity bits are necessary because 2^4 = 16, which is greater than or equal to 10 + 4 + 1 = 15.

Finding the Code Word Using Hamming Algorithm:

Next, once we've identified that 4 parity bits are needed, we can arrange the data bits and calculate the parity bits:

  1. Mark positions that are powers of 2 as parity bits (P1, P2, P4, P8).
  2. Place the data bits in the other positions.
  3. Calculate the parity bits' values based on the even parity rule.

Following this process, the 10-bit information word '1001100110' is expanded with parity bits and arranged as follows:

  • P1 -
  • P2 -
  • 1 (data bit 1)
  • P4 -
  • 0 (data bit 2)
  • 0 (data bit 3)
  • 1 (data bit 4)
  • P8 -
  • 1 (data bit 5, and so on)

Calculating the parity bits for the above arrangement, we'll set each parity bit to ensure even parity for their respective groups. The final code word would look something like 'parity parity 1 parity 0 0 1 parity 1 0 0 1 1 0 1 0', where each 'parity' placeholder is replaced by the respective calculated parity value.

User ColinShark
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