| 摘要 |
PURPOSE:To suppress the entire frequency component of a coded series by suppressing the low frequency component of an error detection code itself. CONSTITUTION:When a discrimination circuit 152 is judged as a parity represents the presence of a low frequency component based on a bit pattern detected by a bit pattern detection circuit 151, an insertion data generating circuit 153 generates a new bit pattern in l-bit to revise a bit not in use. Then the new bit pattern is used the bit not in use and the parity is calculated again and the discrimination circuit 152 is judged again whether or not the bit pattern of the new parity represents the presence of the low frequency component. Then the operation above is repeated till the parity of the pattern whose low frequency component is suppressed. Thus, the low frequency component of the code series is suppressed and excellent code transmission is attained. |
