发明名称 |
AGC CIRCUIT FOR A DIGITAL RECEIVER |
摘要 |
An AGC circuit for a digital receiver that receives a digital television signal or the like, including a pilot, and formatted in a plurality of repetitive data segments, each data segment comprising a fixed number of multilevel symbols occurring at a constant symbol rate. The multilevel symbo ls are converted to corresponding digital values and the pilot (represented by a DC offset) is removed from the digital values. Every fourth symbol is sample d and the samples are accumulated and divided to derive an average symbol valu e. The average symbol value is compared with a reference average symbol value a nd the result of the comparison is an AGC potential that controls the tuner and IF gains. A cable/terrestrial input alters the sampling for cable signals to compensate for high level sweep testing in cable systems.
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申请公布号 |
CA2204722(C) |
申请公布日期 |
2001.10.09 |
申请号 |
CA19952204722 |
申请日期 |
1995.10.26 |
申请人 |
ZENITH ELECTRONICS CORPORATION |
发明人 |
CITTA, RICHARD W.;MUTZABAUGH, DENNIS M.;SGRIGNOLI, GARY J. |
分类号 |
H04N5/52;H03G3/20;H03G3/30;H04L25/03;H04L25/06;H04L27/02;H04L27/06;H04L27/38;(IPC1-7):H04N5/52;H04N7/015 |
主分类号 |
H04N5/52 |
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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