US6167240A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System and method relating to cellular communication systems
Assignee: Telefonaktiebolaget LM Ericsson AB
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Filing: 1998-05-29
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Granted: 2000-12-26
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Expires: 2018-05-29
Abstract
Abstract A system and a method reduce interference in a cellular communication system including at least one controlling arrangement communicating with a number of base stations, each of which serves a cell, and a number of mobile stations controlled by the base stations. Each base station includes a detecting device for detecting interfering signals from one or more mobile stations controlled by other base stations. The base stations also include an alarm activating device for activating the transmission of an alarm signal if interference is detected. The controlling arrangement includes a device for requesting identification of all mobile station in the neighborhood of the interfered base station. A device is also provided for establishing by which base station an interfering mobile station is controlled, and the base station controlling the interfering mobile station takes the appropriate action to reduce the interference level.
Inventors
- 👤 Roland Carlsson
- 👤 Torbjorn Karlsson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 23:34
CPC Classifications
H; H04; H04W; H04W52/00; H04W52/04; H04W52/38; H04W52/40; H04W52/18; H04W52/24; H04W52/243; H04W52/244
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
132 words
A system for reducing interference in a cellular communication system, said system comprising at least one controlling arrangement communicating with a number of base stations, each base station serving a cell, and a number of mobile stations, controlled by said base stations, wherein each base station comprises detecting means for detecting interfering signals from one or more mobile station(s) controlled by other base station(s), and alarm activating means for activating the transmission of an alarm signal if interference is detected, and the controlling arrangement comprises means for requesting identification of all mobile stations in the neighbourhood of the interfered base station and means for establishing by which base station an interfering mobile station is controlled, the base stations controlling an interfering mobile station taking the appropriate action to reduce the interference level.
Claim 2
Independent Claim
132 words
A system for reducing interference in a cellular communication system, said system comprising at least one controlling arrangement communicating with a number of base stations, each base station serving a cell, and a number of mobile stations, controlled by said base stations, wherein each base station comprises detecting means for detecting interfering signals from one or more mobile station(s) controlled by other base station(s), and alarm activating means for activating the transmission of an alarm signal if interference is detected, and the controlling arrangement comprises means for requesting identification of all mobile stations in the neighbourhood of the interfered base station and means for establishing by which base station an interfering mobile station is controlled, the base stations controlling an interfering mobile station taking the appropriate action to reduce the interference level.
Claim 3
Dependent Claim
27 words
The system of claim 1, wherein all mobile stations in the neighbourhood of the interfered base station are requested to transmit identification signals when interference is detected.
Claim 4
Dependent Claim
18 words
The system of claim 2, wherein the base stations contain identification means for identifying an interfering mobile station.
Claim 5
Dependent Claim
33 words
The system of claim 2, wherein at least for a number of mobile stations the identification signal is produced by a variation in the transmitting power of the one or more mobile station.
Claim 6
Dependent Claim
31 words
The system of claim 12, wherein the identification signal is produced by power control means in the base station through modulating the transmitting power of the one or more mobile station.
Claim 7
Dependent Claim
54 words
The system of claim 2, wherein at least a number of mobile stations comprise spreading means for signal multiplication by a short code and wherein the identification signals comprise signals spread by said short code, which is common for at least a number of mobile stations, and the identity of the respective mobile station.
Claim 8
Dependent Claim
30 words
The system of claim 2, wherein at least a number of mobile station are capable of transmitting multiple signals, the identification signal being transmitted in parallell to the normal transmission.
Claim 9
Dependent Claim
25 words
The system of claim 2, wherein the identification signal comprises information about the identity of the mobile station and about the base station controlling it.
Claim 10
Dependent Claim
20 words
The system of claim 1, wherein a the alarm signal is transmitted if the interference level exceeds a threshold level.
Claim 11
Dependent Claim
18 words
The system of claim 1, wherein the controlling arrangement is provided in an exchange a base station controller.
Claim 12
Dependent Claim
16 words
The system of claim 1, wherein the controlling arrangement is a separate arrangement in the network.
Claim 13
Dependent Claim
43 words
The system of claim 1, wherein when it has been established in the interfered base station which mobile station is the interfering mobile station, the interfered base station sends an information signal containing information about the interfering mobile station to the controlling means.
Claim 14
Dependent Claim
34 words
The system of claim 12, wherein the controlling means sends a command to the base station controlling the interfering mobile station ordering it to take the appropriate action to reduce or stop the interfering.
Claim 15
Dependent Claim
17 words
The system of claim 1, wherein the cellular communication system uses a code division multiple access system.
Claim 16
Dependent Claim
40 words
The system of claim 1, wherein the detecting means at least comprises detecting means for detecting interfering signals producing an interference level which is such that the mobile stations controlled by the disturbed base station are prevented from being detected.
Claim 17
Dependent Claim
35 words
The system of claim 1, wherein the detecting means at least comprises detecting means for detecting interfering signals exceeding a given threshold value still allowing detection of mobile stations controlled by the base station itself.
Claim 18
Dependent Claim
12 words
The system of claim 1, wherein the interfering mobile station is stationary.
Claim 19
Dependent Claim
32 words
The system of claim 1, wherein the action to reduce the interference level is to stop transmission, to change transmitting frequency, to perform a soft handover or to lower the transmission power.
Claim 20
Independent Claim
84 words
A method of reducing interference in a cellular communication system, particularly a CDMA-system, including a number of base stations and a number of mobile stations, the method comprising the steps of: detecting interference in an interfered base station, requesting identification of every mobile station in the neighbourhood of the interfered base station not controlled by the interfered base station, identifying the interfering mobile station(s), ordering the base station(s) controlling the interfering mobile station(s) to take an action to at least reduce the interference level.
Claim 21
Independent Claim
84 words
A method of reducing interference in a cellular communication system, particularly a CDMA-system, including a number of base stations and a number of mobile stations, the method comprising the steps of: detecting interference in an interfered base station, requesting identification of every mobile station in the neighbourhood of the interfered base station not controlled by the interfered base station, identifying the interfering mobile station(s), ordering the base station(s) controlling the interfering mobile station(s) to take an action to at least reduce the interference level.
Claim 22
Dependent Claim
64 words
The method of claim 19, further including the steps of: informing controlling means controlling a number of base stations that a base station is interfered, providing from said controlling means the transmission of identification signals from the mobile stations, identifying which is/are the interfering mobile station(s) in the interfered base station, informing the controlling means about which mobile station(s) is/are the interfering mobile station(s).
Claim 23
Dependent Claim
14 words
The method of claim 20, wherein the controlling means are provided in an exchange.
Claim 24
Dependent Claim
53 words
The method of claim 19, further comprising the steps of: detecting an interfering signal which produces an interference level which is so high as to prevent detection of mobile stations controlled by the interfered base station, and detecting interfering signals producing an interference level which is lower, but exceeds a given threshold value.
Claim 25
Dependent Claim
22 words
The method of claim 19, further comprising the step of: modulating the transmitting power of the mobile stations to provide identification signals.
Claim 26
Dependent Claim
22 words
The method of claim 19, further comprising the step of: multiplying the identification signal by a short code in a mobile station.
Claim 27
Dependent Claim
28 words
The method of claim 19, further comprising the step of: transmitting an identification signal in parallell to the normal transmission from at least a number of mobile stations.
Claim 28
Dependent Claim
28 words
The method of claim 24, further comprising the step of: transmitting an identification signal in parallell to the normal transmission from at least a number of mobile stations.
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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) | 2003-12-26 | 2004-06-26 | 2004-12-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-12-26 | 2008-06-26 | 2008-12-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-12-26 | 2012-06-26 | 2012-12-26 | $7700.00 | Window Closed / Lapsed |