发明名称 |
Method and apparatus for detecting control signals |
摘要 |
The present invention provides a method and apparatus for detecting control signal information for an element of a communication system. The control signal information is included in one or more segments of a signal communicated over a communication system channel. The invention provides for the application of a plurality of tapers to a segment of a communicated signal; the transformation of a tapered segment; the determination of a similarity score based on a transform of a tapered segment and a model of a control signal; the identification of control signal information based on a similarity score; and the creation of an indicator signal representative of the identified control signal information to the communication system element. The control signal information may comprise a dual-tone multi-frequency signal. The tapers may comprise a discrete prolate spheroidal sequence. A similarity score may be determined based on a ratio of energy distributions. The numerator of the ratio may comprise an energy distribution based on a control signal model, and the denominator of the ratio may comprise an energy distribution based on a difference between a transformed tapered segment and the control signal model.
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申请公布号 |
US5442696(A) |
申请公布日期 |
1995.08.15 |
申请号 |
US19910816332 |
申请日期 |
1991.12.31 |
申请人 |
AT&T CORP. |
发明人 |
LINDBERG, CRAIG R.;THOMSON, DAVID J. |
分类号 |
H04Q1/45;H04L27/30;H04Q1/457;(IPC1-7):H04M3/00 |
主分类号 |
H04Q1/45 |
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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