US5420896A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Synchronous spread-spectrum communications system and method
Assignee: InterDigital Technology Corp
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Filing: 1993-06-11
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Granted: 1995-05-30
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Expires: 2013-06-11
Abstract
Abstract A spread spectrum communications system for use over a communications channel, including a transmitter-generic-chip-code generator, a transmitter-message-chip-code generator, an EXCLUSIVE-OR gate, a combiner, a transmitter, a receiver-generic-chip-code generator, a receiver-generic mixer, a generic-bandpass filter, a receiver-message-chip-code generator, a receiver-message mixer, a message-bandpass filter, and a synchronous detector. The transmitter-generic-chip-code generator generates a generic-chip-code signal and the transmitter-message-chip-code generator generates a message-chip-code signal. The EXCLUSIVE-OR gate spread-spectrum processes message data with the message-chip-code signal to generate a spread-spectrum signal. The combiner combines the generic-chip-code signal with the spread-spectrum signal. The transmitter transmits the combined generic-chip-code signal and spread-spectrum signal, on a carrier signal over the communications channel as a spread-spectrum-communications signal. The receiver-generic-chip-code generator generates a replica of the generic-chip-code signal. The generic mixer recovers the carrier signal from the spread-spectrum-communications signal. The receiver-message-chip-code generator generates a replica of the message-chip-code signal. The receiver-message mixer despreads the spread-spectrum-communications signal as a modulated-data signal. The tracking and acquisition circuit uses the recovered carrier signal for synchronizing the replicas of the generic-chip-code signal to the recovered carrier signal. The synchronous detector synchronously demodulates the modulated-data signal as received data.
Inventors
- 👤 Donald L. Schilling
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:29
CPC Classifications
H; H04; H04W; H04W52/00; H04W52/04; H04W52/30; H04W52/34; H04W52/343; G; G01; G01S; G01S13/00; G01S13/74; G01S13/82; G01S5/00; G01S5/0009; G01S5/0018; G01S5/0036; G01S5/02; G01S5/14; H04B; H04B1/00; H04B1/69; H04B1/707; H04J; H04J13/00; H04W52/346; H04B7/00; H04B7/14; H04B7/15; H04B7/185; H04B7/1853; H04B7/18545; H04B7/18547
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
166 words
A spread-spectrum communications system for communicating message data comprising: first generic means for generating a generic-chip-code signal; spreading means for spread-spectrum processing the message data, synchronized with the generic chip-code signal, as spread-spectrum-processed-message data; combiner means for combining the generic-chip-code signal with the spread-spectrum-processed-message data, thereby generating a base code-division-multiplex (CDM) signal; transmitter means for transmitting, using radio waves traversing free space, the CDM signal over a communications channel; detection means, coupled to said communications channel, for detecting the generic-chip-code signal embedded in the CDM signal, said detection means including, receiving means for receiving the CDM signal; second generic means, coupled to said receiving means, for detecting the generic-chip-code signal embedded in the CDM signal and for generating a replica of the first generic-chip-code signal; despreading means, synchronized with the replica of the first generic-chip-code signal, for despreading the spread-spectrum-processed-message data as a despread signal; and data detection means, synchronized with the replica of the first generic-chip-code signal, for detecting message data in the despread signal.
Claim 2
Dependent Claim
166 words
A spread-spectrum communications system for communicating message data comprising: first generic means for generating a generic-chip-code signal; spreading means for spread-spectrum processing the message data, synchronized with the generic chip-code signal, as spread-spectrum-processed-message data; combiner means for combining the generic-chip-code signal with the spread-spectrum-processed-message data, thereby generating a base code-division-multiplex (CDM) signal; transmitter means for transmitting, using radio waves traversing free space, the CDM signal over a communications channel; detection means, coupled to said communications channel, for detecting the generic-chip-code signal embedded in the CDM signal, said detection means including, receiving means for receiving the CDM signal; second generic means, coupled to said receiving means, for detecting the generic-chip-code signal embedded in the CDM signal and for generating a replica of the first generic-chip-code signal; despreading means, synchronized with the replica of the first generic-chip-code signal, for despreading the spread-spectrum-processed-message data as a despread signal; and data detection means, synchronized with the replica of the first generic-chip-code signal, for detecting message data in the despread signal.
Claim 3
Dependent Claim
86 words
The spread-spectrum communications system as set forth in claim 1 wherein said despreading means includes, a message-chip-code generator for generating a message-chip-code signal synchronized to the replica of the generic-chip-code signal; a product detector for mixing the message-chip-code signal with a received CDM signal to generate a detected spread-spectrum signal; and a bandpass filter for filtering the detected spread-spectrum signal; and said data detection means includes a data detector, synchronized with the replica of the generic-chip-code signal, for detecting message data in the detected spread-spectrum signal.
Claim 4
Dependent Claim
169 words
A spread-spectrum communications system for communicating message data comprising: a generic-chip-code generator for generating a generic-chip-code signal; a spread-spectrum modulator for spread-spectrum processing the message data, synchronized with the generic-chip-code signal, as spread-spectrum-processed-message data; a combiner for combining the generic-chip-code signal with the spread-spectrum-processed-message data, thereby generating a code-division-multiplexed (CDM) signal; a transmitter for transmitting, using radio waves traversing free space, the CDM signal over a communications channel; a detector, coupled to said communications channel, for detecting the generic-chip-code signal embedded in the CDM signal, said detector including, a receiver-generic-chip-code generator, synchronized to the detected-generic-chip-code signal, for generating a replica of the generic-chip-code signal; a message-chip-code generator for generating, synchronized to the replica of the generic-chip-code signal, a message-chip-code signal; a product detector for mixing the message-chip-code signal with a received CDM signal to generate a detected spread-spectrum signal; a bandpass filter for filtering the detected spread-spectrum signal; and a data detector, synchronized with the replica of the generic-chip-code signal, for detecting message data in the detected spread-spectrum signal.
Claim 5
Dependent Claim
169 words
A spread-spectrum communications system for communicating message data comprising: a generic-chip-code generator for generating a generic-chip-code signal; a spread-spectrum modulator for spread-spectrum processing the message data, synchronized with the generic-chip-code signal, as spread-spectrum-processed-message data; a combiner for combining the generic-chip-code signal with the spread-spectrum-processed-message data, thereby generating a code-division-multiplexed (CDM) signal; a transmitter for transmitting, using radio waves traversing free space, the CDM signal over a communications channel; a detector, coupled to said communications channel, for detecting the generic-chip-code signal embedded in the CDM signal, said detector including, a receiver-generic-chip-code generator, synchronized to the detected-generic-chip-code signal, for generating a replica of the generic-chip-code signal; a message-chip-code generator for generating, synchronized to the replica of the generic-chip-code signal, a message-chip-code signal; a product detector for mixing the message-chip-code signal with a received CDM signal to generate a detected spread-spectrum signal; a bandpass filter for filtering the detected spread-spectrum signal; and a data detector, synchronized with the replica of the generic-chip-code signal, for detecting message data in the detected spread-spectrum signal.
Claim 6
Dependent Claim
135 words
A spread-spectrum communications method for communicating message data, comprising the steps of: generating a generic-chip-code signal; synchronizing the message data with the generic-chip-code signal; spread-spectrum processing the message data as a spread-spectrum-processed-message data; combining the generic-chip-code signal with the spread-spectrum-processed-message data, thereby generating a code-division-multiplexed (CDM) signal; transmitting, using radio waves traversing free space, the CDM signal over a communications channel; detecting, from the communications channel, the generic-chip-code signal embedded in the CDM signal; generating, synchronized to the detected-generic-chip-code signal, a replica of the generic-chip-code signal; generating, synchronized to the replica of the generic-chip-code signal, a message-chip-code signal; mixing the message-chip-code signal with a received CDM signal to generate a detected spread-spectrum signal; filtering the detected spread-spectrum signal; and detecting, synchronized to the replica of the generic-chip-code signal, message data in the detected spread-spectrum signal.
Claim 7
Dependent Claim
135 words
A spread-spectrum communications method for communicating message data, comprising the steps of: generating a generic-chip-code signal; synchronizing the message data with the generic-chip-code signal; spread-spectrum processing the message data as a spread-spectrum-processed-message data; combining the generic-chip-code signal with the spread-spectrum-processed-message data, thereby generating a code-division-multiplexed (CDM) signal; transmitting, using radio waves traversing free space, the CDM signal over a communications channel; detecting, from the communications channel, the generic-chip-code signal embedded in the CDM signal; generating, synchronized to the detected-generic-chip-code signal, a replica of the generic-chip-code signal; generating, synchronized to the replica of the generic-chip-code signal, a message-chip-code signal; mixing the message-chip-code signal with a received CDM signal to generate a detected spread-spectrum signal; filtering the detected spread-spectrum signal; and detecting, synchronized to the replica of the generic-chip-code signal, message data in the detected spread-spectrum signal.
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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) | 1998-05-29 | 1998-11-28 | 1999-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-05-29 | 2002-11-28 | 2003-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-05-29 | 2006-11-28 | 2007-05-30 | $7700.00 | Window Closed / Lapsed |