US5581548A
Expired / Lapsed
US
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Frequency and channel hopping communication in a TDMA cellular mobile radio system
Assignee: Telefonaktiebolaget LM Ericsson AB
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Filing: 1994-12-19
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Granted: 1996-12-03
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Expires: 2014-12-19
Abstract
Abstract According to method and apparatus for communication in a cellular TDMA mobile radio communication system with channel hopping, base and mobile stations transmit radio signal bursts in time slots of a plurality of radio channels in accordance with channel hopping schemes. All of the schemes used by a base and mobile stations in a cell are free from coincidence on any radio channel with any other of the schemes used for transmission within the same cell. A scheme used by a mobile station in one cell occasionally coincides on a radio channel with a scheme used by a mobile station in another cell. The major part of every channel shifting scheme used by a mobile station in a cell is free from coincidence on any radio channel with the major part of any channel hopping scheme used by a mobile station in another cell. The signal to interference ratio or other signal characteristics such as signal strength or bit error rate for signals received by mobile stations are estimated and compared, and the output power of stations are controlled. The existence of further possible channel hopping schemes in a cell, free from coincidence on every radio channel with every other of the channel hopping schemes already in use in that cell, is checked. When another connection to a particular mobile is desired and there is a possible mobile scheme free from coincidence, the desired connection is established using the possible channel hopping scheme in the cell, only if the estimated C/I for certain mobile stations involved in connections exceeds a minimum level.
Inventors
- 👤 Jon K. Ugland
- 👤 Perols B. O. Gudmundson
- 👤 Johan Skold
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:07
CPC Classifications
H; H04; H04W; H04W16/00; H04W16/02; H04W16/12; H04B; H04B1/00; H04B1/69; H04B1/713; H04B1/715; H04B7/00; H04B7/24; H04B7/26; H04B7/2621; H04J; H04J13/00; H04W16/10; H04B2001/7154
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
138 words
A method for transmitting radio signals in a time division multiple access (TDMA) radiocommunication system comprising the steps of: providing first and second cells adjacent one another, each cell having respective first and second base stations; allocating a first set and a second set of TDMA radio channels for usage by said first and second base stations, respectively, said first and second sets including substantially the same channels, said channels including timeslots organized into frames; transmitting radio signals from said first base station, on no more than a maximum number of said timeslots in each frame, said maximum number being less than a total number of available timeslots assigned to said first set of radio channels; and transmitting radio signals from said second base station, on no more than said maximum number of said timeslots in each frame.
Claim 2
Independent Claim
138 words
A method for transmitting radio signals in a time division multiple access (TDMA) radiocommunication system comprising the steps of: providing first and second cells adjacent one another, each cell having respective first and second base stations; allocating a first set and a second set of TDMA radio channels for usage by said first and second base stations, respectively, said first and second sets including substantially the same channels, said channels including timeslots organized into frames; transmitting radio signals from said first base station, on no more than a maximum number of said timeslots in each frame, said maximum number being less than a total number of available timeslots assigned to said first set of radio channels; and transmitting radio signals from said second base station, on no more than said maximum number of said timeslots in each frame.
Claim 3
Dependent Claim
27 words
The method of claim 1, wherein said maximum number of timeslots is equal to 60 percent of the available timeslots assigned to said first set of channels.
Claim 4
Dependent Claim
133 words
A TDMA radiocommunication system including first and second cells adjacent one another, said system comprising: first and second base stations disposed in said first and second cells, respectively; a first set and a second set of TDMA radio channels for usage by said first and second base stations, respectively, said first and second sets including substantially the same channels, said channels including timeslots organized into frames; a first transmitter, in said first base station, which transmits signals on up to a maximum number of said timeslots in each frame, said maximum number being less than a total number of available timeslots assigned to said first set of radio channels; and a second transmitter, in said second base station, which transmits signals on up to said maximum number of said timeslots in each frame.
Claim 5
Dependent Claim
133 words
A TDMA radiocommunication system including first and second cells adjacent one another, said system comprising: first and second base stations disposed in said first and second cells, respectively; a first set and a second set of TDMA radio channels for usage by said first and second base stations, respectively, said first and second sets including substantially the same channels, said channels including timeslots organized into frames; a first transmitter, in said first base station, which transmits signals on up to a maximum number of said timeslots in each frame, said maximum number being less than a total number of available timeslots assigned to said first set of radio channels; and a second transmitter, in said second base station, which transmits signals on up to said maximum number of said timeslots in each frame.
Claim 6
Dependent Claim
27 words
The system of claim 3, wherein said maximum number of timeslots is equal to 60 percent of the available timeslots assigned to said first set of channels.
Claim 7
Independent Claim
131 words
A method for transmitting radio signals associated with connections in a time division multiple access (TDMA) radiocommunication system comprising the steps of: providing first and second cells adjacent one another, each cell having respective first and second base stations; allocating a first set and second set of TDMA radio channels for usage by said first and second base stations, respectively, said first and second sets simultaneously including substantially the same channels; transmitting radio signals from a transmitter to remote stations in said first and second cells using said first and second sets of radio channels, respectively; and limiting an average number of simultaneous connections in said first and second cells to be substantially less than an average number of timeslots on said radio channels in said first and second sets, respectively.
Claim 8
Independent Claim
131 words
A method for transmitting radio signals associated with connections in a time division multiple access (TDMA) radiocommunication system comprising the steps of: providing first and second cells adjacent one another, each cell having respective first and second base stations; allocating a first set and second set of TDMA radio channels for usage by said first and second base stations, respectively, said first and second sets simultaneously including substantially the same channels; transmitting radio signals from a transmitter to remote stations in said first and second cells using said first and second sets of radio channels, respectively; and limiting an average number of simultaneous connections in said first and second cells to be substantially less than an average number of timeslots on said radio channels in said first and second sets, respectively.
Claim 9
Dependent Claim
25 words
The method of claim 5, wherein said average number of simultaneous connections is approximately 60 percent of said average number timeslots on said radio channels.
Claim 10
Dependent Claim
49 words
The method of claim 5, wherein said first and second sets of radio channels can simultaneously be substantially the same channels by providing that said step of transmitting further comprises the step of: hopping among said channels in said first and second sets of channels in a non-coinciding manner.
Claim 11
Dependent Claim
30 words
The method of claim 7, further comprising the step of: transmitting hopping information from said first and second base stations to said remote stations in said first and second cells.
Claim 12
Dependent Claim
108 words
A radiocommunication system including first and second cells adjacent one another, said system comprising: a first set and second set of TDMA radio channels for usage by said first and second base stations, respectively, said first and second sets simultaneously including substantially the same channels; first and second transmitters for transmitting signals to remote stations in said first and second cells using said first and second sets of radio channels, respectively; and means for limiting an average number of simultaneous connections in said first and second cells to be substantially less than an average number of timeslots on said radio channels in said first and second sets, respectively.
Claim 13
Dependent Claim
108 words
A radiocommunication system including first and second cells adjacent one another, said system comprising: a first set and second set of TDMA radio channels for usage by said first and second base stations, respectively, said first and second sets simultaneously including substantially the same channels; first and second transmitters for transmitting signals to remote stations in said first and second cells using said first and second sets of radio channels, respectively; and means for limiting an average number of simultaneous connections in said first and second cells to be substantially less than an average number of timeslots on said radio channels in said first and second sets, respectively.
Claim 14
Dependent Claim
25 words
The system of claim 9, wherein said average number of simultaneous connections is approximately 60 percent of said average number timeslots on said radio channels.
Claim 15
Dependent Claim
44 words
The system of claim 9, wherein said first and second sets of radio channels can simultaneously be substantially the same channels and said system further comprises: means for hopping among said channels in said first and second sets of channels in a non-coinciding manner.
Claim 16
Dependent Claim
22 words
The system of claim 11, wherein said transmitters also transmit hopping information to said remote stations in said first and second cells.
Claim 17
Independent Claim
181 words
A method for transmitting radio signals in a time division multiple access (TDMA) radiocommunication system comprising the steps of: providing first and second cells adjacent one another, each cell having respective first and second base stations; allocating a first set and second set of TDMA radio channels for usage by said first and second base stations, respectively, said first and second sets including substantially the same channels; estimating signal-to-interference ratios for signals received from mobile stations in the first cell in said first base station and the second cell in said second base station; comparing the estimated signal-to-interference ratios with a desired signal-to-interference ratio; identifying one of said TDMA radio channels in said first set which is currently unused in the first cell; and establishing one or more connections between said mobile stations and one of said first base station and said second base station using said one of said TDMA radio channels in said first set if said estimated signal-to-interference ratios based upon mobile stations in at least one of said first and second cells exceed the desired signal-to-interference ratio.
Claim 18
Independent Claim
181 words
A method for transmitting radio signals in a time division multiple access (TDMA) radiocommunication system comprising the steps of: providing first and second cells adjacent one another, each cell having respective first and second base stations; allocating a first set and second set of TDMA radio channels for usage by said first and second base stations, respectively, said first and second sets including substantially the same channels; estimating signal-to-interference ratios for signals received from mobile stations in the first cell in said first base station and the second cell in said second base station; comparing the estimated signal-to-interference ratios with a desired signal-to-interference ratio; identifying one of said TDMA radio channels in said first set which is currently unused in the first cell; and establishing one or more connections between said mobile stations and one of said first base station and said second base station using said one of said TDMA radio channels in said first set if said estimated signal-to-interference ratios based upon mobile stations in at least one of said first and second cells exceed the desired signal-to-interference ratio.
Claim 19
Dependent Claim
35 words
The method of claim 13, wherein said step of establishing further comprises the step of: establishing said connection if said estimated signal-to-interference ratios from mobile stations in said first cell exceed the desired signal-to-interference ratio.
Claim 20
Dependent Claim
40 words
The method of claim 13, wherein said step of establishing further comprises the step of: establishing said connection if said estimated signal-to-interference ratios from mobile stations in both said first cell and said second cell exceed the desired signal-to-interference ratio.
Claim 21
Dependent Claim
47 words
The method of claim 13, wherein said step of establishing further comprises the step of: establishing said connection if said estimated signal-to-interference ratios from mobile stations in said first cell, said second cell and any other cell adjacent to said first cell exceed the desired signal-to-interference ratio.
Claim 22
Dependent Claim
72 words
The method of claim 13, further comprising the steps of: hopping connections in said first cell from one channel in said first set to another channel in said first set according to predetermined hopping sequences; identifying a hopping sequence which hops to channels in said first set free of coincidence from other hopping sequences which are already in use in said first cell; and assigning said hopping sequence to said established connection.
Claim 23
Dependent Claim
147 words
A time division multiple access (TDMA) radiocommunication system comprising: first and second cells adjacent one another, each cell having respective first and second base stations; a first set and second set of TDMA radio channels for usage by said first and second base stations, respectively, said first and second sets including substantially the same channels; means, disposed in said first and second base stations, for estimating signal-to-interference ratios for signals received from mobile stations in the first cell and in the second cell, respectively; means for comparing the estimated signal-to-interference ratios with a desired signal-to-interference ratio; means for establishing one or more connections between said mobile stations and one of said first base station and said second base station using a currently unused one of said TDMA radio channels in said first set if estimated signal-to-interference ratios based upon certain mobile stations exceed said desired signal-to-interference ratio.
Claim 24
Dependent Claim
147 words
A time division multiple access (TDMA) radiocommunication system comprising: first and second cells adjacent one another, each cell having respective first and second base stations; a first set and second set of TDMA radio channels for usage by said first and second base stations, respectively, said first and second sets including substantially the same channels; means, disposed in said first and second base stations, for estimating signal-to-interference ratios for signals received from mobile stations in the first cell and in the second cell, respectively; means for comparing the estimated signal-to-interference ratios with a desired signal-to-interference ratio; means for establishing one or more connections between said mobile stations and one of said first base station and said second base station using a currently unused one of said TDMA radio channels in said first set if estimated signal-to-interference ratios based upon certain mobile stations exceed said desired signal-to-interference ratio.
Claim 25
Dependent Claim
17 words
The system of claim 18, wherein said certain mobile stations comprise mobile stations in said first cell.
Claim 26
Dependent Claim
22 words
The system of claim 18, wherein said certain mobile stations comprise mobile stations in both said first cell and said second cell.
Claim 27
Dependent Claim
29 words
The system of claim 18, wherein said certain mobile stations comprise mobile stations in said first cell, said second cell and any other cell adjacent to said first cell.
Claim 28
Dependent Claim
75 words
The system of claim 18, further comprising: means for hopping connections in said first cell from one channel in said first set to another channel in said first set according to predetermined hopping sequences; means for identifying a hopping sequence which hops to channels in said first set free of coincidence from other hopping sequences which are already in use in said first cell; and means for assigning said hopping sequence to said established connection.
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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) | 1999-12-03 | 2000-06-03 | 2000-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-12-03 | 2004-06-03 | 2004-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-12-03 | 2008-06-03 | 2008-12-03 | $7700.00 | Window Closed / Lapsed |