Difference between revisions of "Error Correction"

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(Created page with "=error CHECKING= One method of error checking would be parity Bits which adds a 1 or 0 to the end of 7 bit code. This additional bit is for even parity and odd parity error ch...")
 
(error CHECKING: Renamed section, reworded and expanded then put into table.)
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=error CHECKING=
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== Parity Checks ==
One method of error checking would be parity Bits which adds a 1 or 0 to the end of 7 bit code. This additional bit is for even parity and odd parity error checking.
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One method of error checking would be parity bits which appends a 1 or 0 to the end of 7 bit packet. This additional bit is for even parity and odd parity error checking.
  
Even parity checks:
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{| class="wikitable"
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|-
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| <b>Even parity</b> || Even parity will check to see if there is an even number of 1's in the first 7 bit of the packet. If there is an even amount, there would be a number 1 appended to the packet, otherwise 0 would be appended to the end of the packet. If there would have been an error in the transmission, the receiving party would receive the packet with either an even number of 1's in the packet but "0" parity bit at the end of the packet or an odd number of 1's in the packet but a "1" party bit.
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|-
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| <b>Odd parity</b>  || Odd parity will check to see if there is an odd number of 1's in the first 7 bit of the packet. If there is an even amount, there would be a number 0 appended to the end of the packet, otherwise 1 would be appended. If an error occurred in the transmission, the receiving party would receive the packet with either an even number of 1's in the packet but "1" parity bit at the end of the packet or an odd number of 1's in the packet but a "0" party bit.
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|}
  
Even parity will check to see if there is an even number of 1's and if there is an off number that means there has been an error in the data.
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However, if there were 2 bits that were transmitted with errors, then the check would not find the errors and it will be sent regardless, causing the parity check to not work.
 
 
Odd parity:
 
 
 
This checks for an odd number of 1's but if there is an even amount and error has occurred.
 
 
 
However if there was 2 bits that were wrong then the check wouldn't find out and it will be sent regardless so the parity check wont work.
 
  
 
=Majority Voting=
 
=Majority Voting=
  
 
Majority voting sends the same bit 3 times and goes with the most common bit for example instead of sending a 1 it would send 1 1 1 and if there was an error it would be 1 1 0 but as there are 2 ones That is what will be used.
 
Majority voting sends the same bit 3 times and goes with the most common bit for example instead of sending a 1 it would send 1 1 1 and if there was an error it would be 1 1 0 but as there are 2 ones That is what will be used.

Revision as of 16:03, 16 December 2016

Parity Checks

One method of error checking would be parity bits which appends a 1 or 0 to the end of 7 bit packet. This additional bit is for even parity and odd parity error checking.

Even parity Even parity will check to see if there is an even number of 1's in the first 7 bit of the packet. If there is an even amount, there would be a number 1 appended to the packet, otherwise 0 would be appended to the end of the packet. If there would have been an error in the transmission, the receiving party would receive the packet with either an even number of 1's in the packet but "0" parity bit at the end of the packet or an odd number of 1's in the packet but a "1" party bit.
Odd parity Odd parity will check to see if there is an odd number of 1's in the first 7 bit of the packet. If there is an even amount, there would be a number 0 appended to the end of the packet, otherwise 1 would be appended. If an error occurred in the transmission, the receiving party would receive the packet with either an even number of 1's in the packet but "1" parity bit at the end of the packet or an odd number of 1's in the packet but a "0" party bit.

However, if there were 2 bits that were transmitted with errors, then the check would not find the errors and it will be sent regardless, causing the parity check to not work.

Majority Voting

Majority voting sends the same bit 3 times and goes with the most common bit for example instead of sending a 1 it would send 1 1 1 and if there was an error it would be 1 1 0 but as there are 2 ones That is what will be used.