US5341397A
Expired / Lapsed
US
⏱️ 0.0 years remaining
CDMA frequency allocation
Assignee: Telefonaktiebolaget LM Ericsson AB
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Filing: 1993-12-08
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Granted: 1994-08-23
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Expires: 2013-12-08
Abstract
Abstract A Code Division Multiple Access (CDMA) communication system which allocates different sets of frequencies to cells with different transmission power levels. Based upon the transmission power levels of a base station for each cell, each base station is assigned to one of at least two groups of base stations. Each group of base stations is assigned a set of frequencies for traffic communication. The set of frequencies assigned to one group of base stations does not overlap with the set of frequencies assigned to a different group of base stations.
Inventors
- 👤 Bjorn Gudmundson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:07
CPC Classifications
H; H04; H04B; H04B7/00; H04B7/14; H04B7/15; H04B7/204; H04B7/216; H04W; H04W52/00; H04W52/04; H04W52/18; H04W52/28; H04W52/283; H04B7/24; H04B7/26; H04B7/2628; H04J; H04J13/00; H04W16/00; H04W52/38; H04W52/50; H04W16/24; H04W16/32; H04W24/00; H04W24/10; H04W28/00; H04W28/16; H04W36/00; H04W36/06; H04W76/00; H04W76/20; H04W76/28; H04W88/00; H04W88/08
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
183 words
In a multiple access, spread spectrum communication system for communication information signals, which include speech, control and pilot-sequence signals, between a plurality of base station and a plurality of mobile stations, a method comprising: coding blocks of bit sequences of an information signal; scrambling each said coded information signal using a unique selected scrambling bit sequence; transmitting said scrambled coded signals from each base station; receiving a composite signal of overlapping, transmitted signals; descrambling said composite signal using one of said unique scrambling bit sequences to distinguish coded information signals from a selected base station from other signals in said composite signal; recursively correlating said composite signal with block codes corresponding to said information signals; determining which block code generates a greatest correlation and producing a correlated signal; successively removing said correlated signal from said composite signal; rescrambling a residual portion of said correlated, composite signal using said corresponding block codes to generate a series of recorded signals; detecting received pilot-sequence signals; measuring the signal strength of each received pilot sequence signal; and storing the measured signal strengths of the received pilot sequences.
Claim 2
Dependent Claim
183 words
In a multiple access, spread spectrum communication system for communication information signals, which include speech, control and pilot-sequence signals, between a plurality of base station and a plurality of mobile stations, a method comprising: coding blocks of bit sequences of an information signal; scrambling each said coded information signal using a unique selected scrambling bit sequence; transmitting said scrambled coded signals from each base station; receiving a composite signal of overlapping, transmitted signals; descrambling said composite signal using one of said unique scrambling bit sequences to distinguish coded information signals from a selected base station from other signals in said composite signal; recursively correlating said composite signal with block codes corresponding to said information signals; determining which block code generates a greatest correlation and producing a correlated signal; successively removing said correlated signal from said composite signal; rescrambling a residual portion of said correlated, composite signal using said corresponding block codes to generate a series of recorded signals; detecting received pilot-sequence signals; measuring the signal strength of each received pilot sequence signal; and storing the measured signal strengths of the received pilot sequences.
Claim 3
Dependent Claim
30 words
A method of communication in a code division multiple access system according to claim 1, further comprising the step of: regularly transmitting the stored signal strengths to a base station.
Claim 4
Dependent Claim
30 words
A method of communication in a code division multiple access system according to claim 1, further comprising the step of: transmitting the stored signal strengths to a requesting base station.
Claim 5
Dependent Claim
226 words
In a multiple access, spread spectrum communication system for communicating information signals, which include speech, control and pilot-sequence signals, between a plurality of base stations and a plurality of mobile stations, a transmitter in each base station including: coding means for coding blocks of bit sequences of an information signal, means for scrambling each information signal using a unique selected scrambling bit sequence corresponding to one of said base stations, and means for transmitting said block coded information signal; and receiving means in each mobile station for receiving a composite signal of overlapping, transmitted signals, including: descrambling means for descrambling said composite signal using one of said unique scrambling bit sequences to distinguish coded information signals from a selected base station from other signals in said composite signal; correlation means for recursively correlating said composite signal with block codes corresponding to said information signals; comparison means for determining a block code that generates a greatest correlation and for producing a correlated signal; signal removal means for successively removing said correlated signal from said composite signal; rescrambling means for recording a residual portion of said correlated, composite signal using said corresponding block codes to generated a series of recorded signals; detection means for detecting received pilot-sequences; measuring the relative signal strength of each received pilot sequence; and storing the measured signal strengths of the received pilot sequences.
Claim 6
Dependent Claim
226 words
In a multiple access, spread spectrum communication system for communicating information signals, which include speech, control and pilot-sequence signals, between a plurality of base stations and a plurality of mobile stations, a transmitter in each base station including: coding means for coding blocks of bit sequences of an information signal, means for scrambling each information signal using a unique selected scrambling bit sequence corresponding to one of said base stations, and means for transmitting said block coded information signal; and receiving means in each mobile station for receiving a composite signal of overlapping, transmitted signals, including: descrambling means for descrambling said composite signal using one of said unique scrambling bit sequences to distinguish coded information signals from a selected base station from other signals in said composite signal; correlation means for recursively correlating said composite signal with block codes corresponding to said information signals; comparison means for determining a block code that generates a greatest correlation and for producing a correlated signal; signal removal means for successively removing said correlated signal from said composite signal; rescrambling means for recording a residual portion of said correlated, composite signal using said corresponding block codes to generated a series of recorded signals; detection means for detecting received pilot-sequences; measuring the relative signal strength of each received pilot sequence; and storing the measured signal strengths of the received pilot sequences.
Claim 7
Dependent Claim
15 words
The system according to claim 4, wherein said block codes are formed using Walsh-Hadamard matrices.
Claim 8
Dependent Claim
14 words
The system according to claim 4, wherein said block codes are orthogonal block codes.
Claim 9
Dependent Claim
14 words
The system according to claim 4, wherein said block codes are bi-orthogonal block codes.
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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) | 1997-08-22 | 1998-02-21 | 1998-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-08-22 | 2002-02-21 | 2002-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-08-22 | 2006-02-21 | 2006-08-23 | $7700.00 | Window Closed / Lapsed |