US6097709A
Expired / Lapsed
US
⏱️ 0.0 years remaining
TDMA cellular communication system using a receiver station for detecting a timing difference between adjacent base stations
Assignee: NEC Corp
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Filing: 1997-12-10
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Granted: 2000-08-01
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Expires: 2017-12-10
Abstract
Abstract In a time-division multiple access cellular mobile communication system, first and second base stations respectively provide coverages over adjacent cells. A receiver station is located in a region where the coverages of the base stations partially overlap for receiving first and second synchronization signals from the first and second base stations, respectively, to detect a time difference between the received synchronization signals. The receiver station then communicates time difference data to the first and second base stations, the data representing the detected time difference and channel identifiers of the first and second base stations. The first and second base stations time-division multiplex the time difference data with a downlink traffic signal and broadcast the multiplexed time difference data. A mobile station is arranged to receive the multiplexed time difference data from the first base station and makes a timing adjustment with respect to the second base station according to the time difference data.
Inventors
- 👤 Kenji Kuwabara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:50
CPC Classifications
H; H04; H04B; H04B7/00; H04B7/24; H04B7/26; H04B7/2662; H04B7/2671; H04B7/2678; H04B7/2687; H04B7/2696; H04B7/2684
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
150 words
A time-division multiple access (TDMA) cellular mobile communication system comprising: first and second base stations respectively providing coverages over adjacent cells; a receiver station located in a region where the coverages of said base stations partially overlap, said receiver station receiving first and second synchronization signals from said first and second base stations, respectively, detecting a time difference between the received synchronization signals and communicating time difference data to said first and second base stations, said data representing the detected time difference and channel identifiers of said first and second base stations, said first and second base stations time-divisions multiplexing said time difference data with a downlink traffic signal and broadcasting the multiplexed time difference data; and a mobile station for receiving the multiplexed time difference data from said first base station and making a timing adjustment with respect to said second base station according to said time difference data.
Claim 2
Dependent Claim
150 words
A time-division multiple access (TDMA) cellular mobile communication system comprising: first and second base stations respectively providing coverages over adjacent cells; a receiver station located in a region where the coverages of said base stations partially overlap, said receiver station receiving first and second synchronization signals from said first and second base stations, respectively, detecting a time difference between the received synchronization signals and communicating time difference data to said first and second base stations, said data representing the detected time difference and channel identifiers of said first and second base stations, said first and second base stations time-divisions multiplexing said time difference data with a downlink traffic signal and broadcasting the multiplexed time difference data; and a mobile station for receiving the multiplexed time difference data from said first base station and making a timing adjustment with respect to said second base station according to said time difference data.
Claim 3
Dependent Claim
97 words
A TDMA cellular mobile communication system as claimed in claim 1, wherein said mobile station is arranged to: store the received time difference data in memory; read the stored time difference data from the memory during an idle slot according to relative field strengths of surrounding base stations; set the mobile station to a radio link specified by the channel identifier of the read time difference data; make said timing adjustment according to the time difference represented by the data read from the memory; and informs the first base station of a result of said timing adjustment.
Claim 4
Dependent Claim
50 words
A TDMA cellular mobile communication system as claimed in claim 2, wherein said mobile station is arranged to expand receive interval of time-division duplex operation after said timing adjustment is made for making a search through said radio link for a synchronization signal and returning the receive interval to normal.
Claim 5
Independent Claim
161 words
A method of synchronizing a mobile station to base stations of a time-division multiple access (TDMA) cellular mobile communication system, comprising the steps of: a) installing a receiver station in a region where coverages of first and second base stations partially overlap; b) receiving, at said receiver station, first and second synchronization signals from said first and second base stations, respectively; c) detecting a time difference between the received synchronization signals; d) communicating time difference data to said first and second base stations, said data representing the detected time difference and channel identifiers of said first and second base stations; e) time-division multiplexing said time difference data, at said first and second base stations, with a downlink traffic signal and broadcasting the multiplexed time difference data; and f) receiving, at a mobile station, the multiplexed time difference data from the first base station and making a timing adjustment with respect to the second base station according to said time difference data.
Claim 6
Independent Claim
161 words
A method of synchronizing a mobile station to base stations of a time-division multiple access (TDMA) cellular mobile communication system, comprising the steps of: a) installing a receiver station in a region where coverages of first and second base stations partially overlap; b) receiving, at said receiver station, first and second synchronization signals from said first and second base stations, respectively; c) detecting a time difference between the received synchronization signals; d) communicating time difference data to said first and second base stations, said data representing the detected time difference and channel identifiers of said first and second base stations; e) time-division multiplexing said time difference data, at said first and second base stations, with a downlink traffic signal and broadcasting the multiplexed time difference data; and f) receiving, at a mobile station, the multiplexed time difference data from the first base station and making a timing adjustment with respect to the second base station according to said time difference data.
Claim 7
Dependent Claim
85 words
The method of claim 4, wherein the step (f) further comprises the steps of: storing the received time difference data in memory; reading the stored time difference data from the memory according to relative field strengths of surrounding base stations; setting the mobile station to a radio link specified by the read time difference data; making said timing adjustment according to the time difference represented by the data read from the memory; and informing the first base station of a result of the timing adjustment.
Claim 8
Dependent Claim
41 words
The method of claim 5, further comprising the steps of: expanding receive interval of time-division duplex operation after said timing adjustment is made; making a search through said radio link for a synchronization signal; and returning the receive interval to normal.
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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) | 2003-08-01 | 2004-01-31 | 2004-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-08-01 | 2008-01-31 | 2008-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-08-01 | 2012-01-31 | 2012-08-01 | $7700.00 | Window Closed / Lapsed |