发明名称 ECHO CANCELLER HAVING IMPROVED NON-LINEAR PROCESSOR
摘要 A non-linear processor (300) for use in an echo canceller (25) is set forth. The non-linear processor (300) includes a center clipping digital filter receiving an echo compensated signal. The non-linear processo r provides a center clipped output signal having non-linear thresholds at values of + T(sub NLP) and -T(sub NLP).The value of T(sub NLP) is dynamically dependent, at least, in part on echo return loss measurements. To limit the processor's susceptibility to corruption from double-talk conditions, the non-linear processor (300) inhibits the dynamic setting of the T(sub NLP) value when a double talk condition is present. Additionally, or in the alternative, the non-linear processor (300) locks the value of the echo return loss measureme nt after a predetermined number of consecutive echo return loss measurements have values falling within a predetermined range of one another. Such locking further reduces the susceptibility of the non-linear processor to corruption from double-talk conditions.
申请公布号 CA2314219(C) 申请公布日期 2007.07.24
申请号 CA19982314219 申请日期 1998.11.13
申请人 TELLABS OPERATIONS INC. 发明人 LIU, TIANFANG;FARRELL, DAVID S.
分类号 H04M9/08;H04B3/23 主分类号 H04M9/08
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