发明名称 |
Digital frequency determining apparatus using matched filters |
摘要 |
Methods and apparatus for determining a dominant frequency contained in a multi-frequency analog signal. An apparatus includes a first matched filter pair and a second a second matched filter pair. Both the first matched filter pair and the second matched filter pair are configured to receive in-phase (I-phase) and quadrature-phase (Q-phase) digital samples of a digitized multi-frequency analog signal. The summed magnitudes of outputs of the first and second matched filter pairs provide an indication of a dominant frequency represented in the digital samples. The first matched filter pair may include first and second matched filters, where the first matched filter includes a multiplier operable to multiply, on a sample-by-sample basis, a sample by a coefficient. A sample comprises an n-bit digital representation of either the I-phase amplitude or the Q-phase ampltude at a given instant. The coefficients are the terms required to complete the matching functions (e.g. 1-bit Walsh coefficients).
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申请公布号 |
US2005286660(A1) |
申请公布日期 |
2005.12.29 |
申请号 |
US20040880108 |
申请日期 |
2004.06.28 |
申请人 |
X-CYTE, INC., A CALIFORNIA CORPORATION |
发明人 |
NYSEN PETER J.;NYSEN PAUL A. |
分类号 |
H04L27/14;H04L27/148;H04L27/152;(IPC1-7):H04L27/14 |
主分类号 |
H04L27/14 |
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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