US4069468A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Doppler spectral measurement
Assignee: Raytheon Co
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Filing: 1976-09-24
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Granted: 1978-01-17
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Expires: 1996-09-24
Abstract
Abstract A system for Doppler frequency measurement, responsive to spectral modulation induced by a reverberant and nonlinear radiation transmissive region such as the ocean, and composed of a Fourier transformer for providing digitally the spectral lines for a set of samples of a Doppler signal, a circuit for obtaining the logarithm of the power spectrum, weighting of the logarithm by othogonal functions, and an arithmetic combination of components of the weighted logarithm.
Inventors
- 👤 James F. Bartram
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:15
CPC Classifications
G; G01; G01R; G01R23/00; G01R23/16; G01R23/165; G01R23/167; G01R23/18; G01S; G01S15/00; G01S15/02; G01S15/50; G01S15/58; G01S15/60; G01S7/00; G01S7/02; G01S7/28; G01S7/285; G01S7/292; G01S7/52; G01S7/523; G01S7/526; G01S7/527; G01S15/06; G01S15/08; G01S15/10; G01S15/18; G01S15/66; Y; Y10; Y10S; Y10S367/00; Y10S367/903; Y10S367/905
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
105 words
A Doppler measurement system comprising: means for sampling a signal received during a predetermined interval of time, said means providing a predetermined number of samples of said received signal during said predetermined interval of time; means for obtaining the power spectrum of a set of said samples consisting of said predetermined number of samples; means coupled to said power spectrum means for forming the logarithm of said spectrum; means coupled to said logarithmic means for multiplying output signals thereof by orthogonal function factors; and means coupled to said multiplying means for combining products of said multiplying means to produce a component of a Doppler frequency.
Claim 2
Dependent Claim
105 words
A Doppler measurement system comprising: means for sampling a signal received during a predetermined interval of time, said means providing a predetermined number of samples of said received signal during said predetermined interval of time; means for obtaining the power spectrum of a set of said samples consisting of said predetermined number of samples; means coupled to said power spectrum means for forming the logarithm of said spectrum; means coupled to said logarithmic means for multiplying output signals thereof by orthogonal function factors; and means coupled to said multiplying means for combining products of said multiplying means to produce a component of a Doppler frequency.
Claim 3
Dependent Claim
66 words
A system according to claim 1 further comprising means for transmitting radiant energy during successive instances of time into a medium productive of echoes of said radiant energy, each of said echoes being received by said system to serve as said received signal, and means coupled to said sampling means for tracking the occurrences of said echoes, said tracking means providing said predetermined interval of time.
Claim 4
Dependent Claim
54 words
A system according to claim 1 wherein said sampling means includes a filter for extracting a nominal value of a Doppler frequency of said received signal, said sampling means further comprising means for offsetting a Doppler spectrum of said received signal by an amount of frequency equal to said nominal value of Doppler frequency.
Claim 5
Dependent Claim
105 words
A system according to claim 1 further comprising means for receiving a plurality of received signals from a plurality of directions, said received signal being one of said plurality of received signals, Doppler means coupled to said receiving means for producing a component of a Doppler frequency of a second received signal of said plurality of received signals, and means coupled to said combining means and to said Doppler means for vectorially summing said components of said Doppler frequencies to provide a magnitude and direction of a Doppler frequency resulting from a combination of Doppler frequencies of a plurality of said plurality of received signals.
Claim 6
Dependent Claim
116 words
In combination: means coupled to a medium propagative of radiant energy for producing echoes of radiant energy therefrom; means synchronized to said echo producing means for filtering a carrier frequency of said echoes; means coupled to said filtering means for providing samples of said echo having a frequency spectrum substantially centered about said carrier frequency; means for transforming a set of said samples to provide a set of orthogonal functions related to said set of samples; means coupled to said transforming means for taking the logarithm of said orthogonal functions; and means coupled to said logarithmic means for forming the weighted summation of said logarithms of said orthogonal functions to provide Doppler data of said echoes.
Claim 7
Dependent Claim
116 words
In combination: means coupled to a medium propagative of radiant energy for producing echoes of radiant energy therefrom; means synchronized to said echo producing means for filtering a carrier frequency of said echoes; means coupled to said filtering means for providing samples of said echo having a frequency spectrum substantially centered about said carrier frequency; means for transforming a set of said samples to provide a set of orthogonal functions related to said set of samples; means coupled to said transforming means for taking the logarithm of said orthogonal functions; and means coupled to said logarithmic means for forming the weighted summation of said logarithms of said orthogonal functions to provide Doppler data of said echoes.
References Cited (Backward Citations)
US3610901A
Cited
US3721977A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-01-16 | 1981-07-18 | 1982-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-16 | 1985-07-18 | 1986-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-16 | 1989-07-18 | 1990-01-17 | $7700.00 | Window Closed / Lapsed |