摘要 |
An (18, 9) error correction code that is simultaneously double error correcting and triple error detecting is disclosed. The code is defined by the following parity check matrix: <maths id="MATH-US-00001" num="00001"> <MATH OVERFLOW="SCROLL"> <MROW> <MSUP> <MUNDER> <MI>beta</MI> <MN>1</MN> </MUNDER> <MROW> <MN>3</MN> <MO></MO> <MSTYLE> <mspace width="0.6em" height="0.6ex"/> </MSTYLE> </MROW> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.6em" height="0.6ex"/> </MSTYLE> <MO></MO> <MSUP> <MUNDER> <MI>beta</MI> <MN>1</MN> </MUNDER> <MN>6</MN> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.8em" height="0.8ex"/> </MSTYLE> <MO></MO> <MSUP> <MUNDER> <MI>beta</MI> <MN>1</MN> </MUNDER> <MN>12</MN> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.3em" height="0.3ex"/> </MSTYLE> <MO></MO> <MSUP> <MROW> <MSUP> <MUNDER> <MI>beta</MI> <MN>1</MN> </MUNDER> <MN>7</MN> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.3em" height="0.3ex"/> </MSTYLE> </MROW> <MSTYLE> <mspace width="0.3em" height="0.3ex"/> </MSTYLE> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.3em" height="0.3ex"/> </MSTYLE> <MO></MO> <MSUP> <MUNDER> <MI>beta</MI> <MN>1</MN> </MUNDER> <MN>14</MN> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.6em" height="0.6ex"/> </MSTYLE> <MO></MO> <MSUP> <MUNDER> <MI>beta</MI> <MN>1</MN> </MUNDER> <MN>11</MN> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.6em" height="0.6ex"/> </MSTYLE> <MO></MO> <MSUP> <MUNDER> <MI>beta</MI> <MN>1</MN> </MUNDER> <MN>5</MN> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.8em" height="0.8ex"/> </MSTYLE> <MO></MO> <MSUP> <MUNDER> <MI>beta</MI> <MN>1</MN> </MUNDER> <MN>1</MN> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.8em" height="0.8ex"/> </MSTYLE> <MO></MO> <MSUP> <MUNDER> <MI>beta</MI> <MN>1</MN> </MUNDER> <MN>2</MN> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.8em" height="0.8ex"/> </MSTYLE> <MO></MO> <MSUP> <MUNDER> <MI>beta</MI> <MN>1</MN> </MUNDER> <MN>4</MN> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.8em" height="0.8ex"/> </MSTYLE> <MO></MO> <MSUP> <MUNDER> <MI>beta</MI> <MN>1</MN> </MUNDER> <MN>8</MN> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.6em" height="0.6ex"/> </MSTYLE> <MO></MO> <MSUP> <MUNDER> <MROW> <MSTYLE> <mspace width="0.3em" height="0.3ex"/> </MSTYLE> <MO></MO> <MI>beta</MI> </MROW> <MN>1</MN> </MUNDER> <MN>16</MN> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.6em" height="0.6ex"/> </MSTYLE> <MO></MO> <MSUP> <MUNDER> <MI>beta</MI> <MN>1</MN> </MUNDER> <MN>15</MN> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.8em" height="0.8ex"/> </MSTYLE> <MO></MO> <MSUP> <MUNDER> <MI>beta</MI> <MN>1</MN> </MUNDER> <MN>13</MN> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.8em" height="0.8ex"/> </MSTYLE> <MO></MO> <MSUP> <MUNDER> <MI>beta</MI> <MN>1</MN> </MUNDER> <MN>9</MN> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.8em" height="0.8ex"/> </MSTYLE> <MO></MO> <MUNDER> <MROW> <MSTYLE> <mspace width="0.3em" height="0.3ex"/> </MSTYLE> <MO></MO> <MN>0</MN> </MROW> <MROW> <MSTYLE> <mspace width="0.3em" height="0.3ex"/> </MSTYLE> <MO></MO> <MN>1</MN> </MROW> </MUNDER> <MO></MO> <MSTYLE> <mspace width="1.4em" height="1.4ex"/> </MSTYLE> <MO></MO> <MSUP> <MUNDER> <MI>beta</MI> <MN>1</MN> </MUNDER> <MN>10</MN> </MSUP> <MO></MO> <MSTYLE> <mspace width="0.6em" height="0.6ex"/> </MSTYLE> <MO></MO> <MUNDER> <MN>1</MN> <MROW> <MN>1</MN> <MO>,</MO> </MROW> </MUNDER> </MROW> </MATH> </MATHS> where beta is a root of the polynomial x<SUP>17</SUP>-1 in the finite field of 256 elements. Logic circuitry for efficiently determining the locations of single and double errors as well as for detecting the presence of uncorrectable errors is also disclosed.
|