发明名称 |
Automatic H-register clear for prevention of erroneous convolution in digital adaptive echo canceller |
摘要 |
An automatic H-register clear system for the prevention of erroneous convolution in adaptive digital echo cancellers is disclosed. Incoming signals from the H-register are accumulated and compared to a predetermined threshold value and when the value is exceeded, the H-register is cleared with the occurrence of the internal housekeeping cycle of the echo canceller. The clearing of the H-register allows a new impulse response model to be generated from new sampled data. In one embodiment using analog implementation, the accumulation takes place using a sequence of signal processing of digital-to-analog conversion, full wave rectification followed by integration of the signal. In another preferred embodiment using a counter detection system, each word is compared to a threshold and if this value is exceeded, a counter is indexed. If the value of the count in the counter exceeds a predetermined number during the sampling interval, the H-register is cleared. In this latter embodiment, either analog or digital implementation can be used.
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申请公布号 |
US4021623(A) |
申请公布日期 |
1977.05.03 |
申请号 |
US19750625354 |
申请日期 |
1975.10.23 |
申请人 |
COMMUNICATIONS SATELLITE CORPORATION (COMSAT) |
发明人 |
SUYDERHOUD, HENRI G.;ONUFRY, JR., MICHAEL;KAUFFMAN, ERIC R. |
分类号 |
H04B3/23;(IPC1-7):H04B3/20 |
主分类号 |
H04B3/23 |
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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