US5396515A
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Asymmetric spread spectrum correlator
Assignee: Intel Corp
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Filing: 1991-05-10
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Granted: 1995-03-07
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Expires: 2011-05-10
Abstract
Abstract An apparatus for decoding a received spread spectrum signal having a data signal modulated with a pseudo-noise code and transmitted as an RF spread spectrum signal. A reference-sequence-storage device holds a reference-pseudo-noise signal, and a receive-sequence storage device holds a received spread spectrum signal. A chip comparator adds each chip of the received spread spectrum signal by each respective chip of the pseudo-noise signal, thereby generating a plurality of chip comparison signals. A summer adds the plurality of chip comparison signals, generating a correlation signal. The comparator compares the correlation signal to a statistically predetermined threshold level, and generates a first data-symbol signal.
Inventors
- 👤 Robert C. Dixon
- 👤 Jeffrey S. Vanderpool
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 01:53
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/69; H04B1/707; H04B1/709; H04B1/7093
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
104 words
Apparatus for decoding a spread spectrum signal, said spread spectrum signal having a data signal modulated with a code, said apparatus comprising means for generating a correlation signal representing a degree of match between said spread spectrum signal and a reference signal corresponding to said code, and means for generating, at selected clock times, either a first data symbol in response to a comparison of said correlation signal and a single threshold level, or a second data symbol at said clock times when said first data symbol is not generated in response to said comparison of said correlation signal and said single threshold level.
Claim 2
Dependent Claim
104 words
Apparatus for decoding a spread spectrum signal, said spread spectrum signal having a data signal modulated with a code, said apparatus comprising means for generating a correlation signal representing a degree of match between said spread spectrum signal and a reference signal corresponding to said code, and means for generating, at selected clock times, either a first data symbol in response to a comparison of said correlation signal and a single threshold level, or a second data symbol at said clock times when said first data symbol is not generated in response to said comparison of said correlation signal and said single threshold level.
Claim 3
Dependent Claim
23 words
The apparatus of claim 1 further comprising synchronization means for synchronizing said selected clock times with the generation of said first data symbol.
Claim 4
Dependent Claim
67 words
Apparatus for decoding a spread spectrum signal, said spread spectrum signal having a data signal modulated with a code of length L, said apparatus comprising means for generating a single correlation pulse after a duration of between L/2+1 and L chips of said spread spectrum signal; and means for generating a first data symbol in response to a comparison of said correlation pulse with a threshold level.
Claim 5
Dependent Claim
67 words
Apparatus for decoding a spread spectrum signal, said spread spectrum signal having a data signal modulated with a code of length L, said apparatus comprising means for generating a single correlation pulse after a duration of between L/2+1 and L chips of said spread spectrum signal; and means for generating a first data symbol in response to a comparison of said correlation pulse with a threshold level.
Claim 6
Dependent Claim
70 words
Apparatus for decoding a spread spectrum signal, said spread spectrum signal having a data signal modulated with a code of length L, said apparatus comprising means for generating a correlation signal for said spread spectrum signal and a signal corresponding to said code; and means for generating a data signal in response to said correlation signal, said data signal comprising one data bit for each L chips in said code.
Claim 7
Dependent Claim
70 words
Apparatus for decoding a spread spectrum signal, said spread spectrum signal having a data signal modulated with a code of length L, said apparatus comprising means for generating a correlation signal for said spread spectrum signal and a signal corresponding to said code; and means for generating a data signal in response to said correlation signal, said data signal comprising one data bit for each L chips in said code.
Claim 8
Dependent Claim
27 words
The apparatus of claim 4 wherein said means for generating a data signal further comprises a means for comparing said correlation signal with a single threshold level.
Claim 9
Dependent Claim
84 words
Apparatus for decoding a spread spectrum signal, said spread spectrum signal having a data signal modulated with a code, said apparatus comprising means for generating a correlation signal for said spread spectrum signal and a signal corresponding to said code, and means for generating a data signal in response to a comparison of said correlation signal with a single threshold, and without reference to a code preamble for said code, said data signal comprising one data symbol for each L chips in said code.
Claim 10
Dependent Claim
84 words
Apparatus for decoding a spread spectrum signal, said spread spectrum signal having a data signal modulated with a code, said apparatus comprising means for generating a correlation signal for said spread spectrum signal and a signal corresponding to said code, and means for generating a data signal in response to a comparison of said correlation signal with a single threshold, and without reference to a code preamble for said code, said data signal comprising one data symbol for each L chips in said code.
Claim 11
Dependent Claim
76 words
Apparatus for decoding a spread spectrum signal, said spread spectrum signal having a data signal modulated with a code, said apparatus comprising means for generating a correlation signal for said spread spectrum signal and a signal corresponding to said code, and means for generating a data signal in response to said correlation signal without reference to a synchronization signal for said code, said data signal comprising one data symbol for each L chips in said code.
Claim 12
Dependent Claim
76 words
Apparatus for decoding a spread spectrum signal, said spread spectrum signal having a data signal modulated with a code, said apparatus comprising means for generating a correlation signal for said spread spectrum signal and a signal corresponding to said code, and means for generating a data signal in response to said correlation signal without reference to a synchronization signal for said code, said data signal comprising one data symbol for each L chips in said code.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-03-06 | 1998-09-05 | 1999-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-03-06 | 2002-09-05 | 2003-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-03-06 | 2006-09-05 | 2007-03-07 | $7700.00 | Window Closed / Lapsed |