发明名称 |
MULTILEVEL MODULATOR COMPRISING A COMPACT ERROR CORRECTING CODE PRODUCING UNIT |
摘要 |
<p>In a multilevel modulator for use in modulating an input digital signal of N levels into a multilevel modulated signal, the input digital signal is converted by a code converting unit into a major converted signal for the input digital signal and a minor converted signal corresponding to the major converted signal. The major converted signal is rearranged into groups each of which consists of a predetermined number of levels smaller than N and which is produced in a time division fashion together with the minor converted signal. A signal producing unit processes each group to produce a Lee-error correcting code sequence. Alternatively, major and minor converted signals are produced on quadrature-phase amplitude modulation of a circular signal arrangement of N-levels to divide the circular signal arrangement into a square signal arrangement and the remaining signal arrangement. In a counterpart multilevel demodulator, an inverse operation is carried out to reproduce the input digital signal.</p> |
申请公布号 |
CA1257665(A) |
申请公布日期 |
1989.07.18 |
申请号 |
CA19860514537 |
申请日期 |
1986.07.24 |
申请人 |
NEC CORPORATION |
发明人 |
NODA, SEIICHI;YOSHIMOTO, MAKOTO |
分类号 |
H03M13/25;H03M13/45;H04L1/00;H04L27/34;(IPC1-7):H04L27/04 |
主分类号 |
H03M13/25 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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