发明名称 |
Duobinary pulse shaping for optical transmission systems employing pulse amplitude modulation techniques |
摘要 |
A duobinary optical communication system is disclosed that employs pulse amplitude modulation (PAM) techniques to provide further improvements in spectral efficiency. A disclosed PAM duobinary optical transmitter converts a plurality of input bits to an N level signal using PAM techniques; adds a current N level signal to a previous N level signal to produce a 2N-1 level signal; and converts the 2N-1 level signal to an optical signal for transmission to a receiver. A disclosed PAM duobinary optical receiver detects a power level of the received optical signal (encoded using pulse amplitude modulation and duobinary encoding techniques to encode a plurality of bits) and maps the detected power level to a plurality of bits to return the transmitted information. An exemplary PAM-4 duobinary optical communication system combines PAM-4 modulation techniques with duobinary pulse shaping techniques to provide an overall factor of four improvement in spectral efficiency by reducing the bandwidth of the optical signal.
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申请公布号 |
US7257329(B2) |
申请公布日期 |
2007.08.14 |
申请号 |
US20030378096 |
申请日期 |
2003.02.28 |
申请人 |
AGERE SYSTEMS INC. |
发明人 |
AZADET KAMERAN;SAIBI FADI RYAD OLIVIER |
分类号 |
H04B10/04;H04B10/12;H04B10/155;H04B10/158;H04B10/18 |
主分类号 |
H04B10/04 |
代理机构 |
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主权项 |
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地址 |
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