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AssigneeTelefonaktiebolaget LM Ericsson
InventorsSven-Olof L. Jonsson, Georg W. R. Chambert, Stig R. Bodin
Estimating the term…
In a cellular mobile radiotelephone system having a plurality of cells providing radio coverage by a plurality of base stations and having a plurality of mobile stations, the location of a mobile station with respect to cell boundaries is identified using measurements, performed at the mobile station or at selected cells, of transmissions from the cells or transmissions from the mobile station. When a cell is found that meets a specified standard with respect to a call connection in progress according to a first radio-signal criterion, a handoff candidate cell is selected according a second different radio-signal criterion. When no cell is found that meet the specified standard, a cell is selected according to the first radio-signal criterion. Handoff to the selected cell is attempted if that cell is not presently handling that call. More particularly, the first radio-signal criterion may be signal strength and the second radio-signal criterion may be path loss. When a cell is found that meets the signal-strength criterion, the cell is determined to have sufficient signal strength margin so that the path loss criterion may be used instead. As mentioned above, use of the path loss criterion has the advantages of conserving power, reducing interference, and allowing effective cell boundaries to remain fixed. When no cell is found that meets the signal-strength criterion, the call connection is determined to be signal-strength limited such that the signal strength criterion is used to select the cell having the greatest signal strength.
In a cellular mobile radiotelephone system having a plurality of cells each providing radio coverage by a base station and having a plurality of mobile stations each associated with one of said cells, a method of call handoff from a first cell to a second cell by using a radio signal criterion based on a path loss relationship between said first and second cells in order to prevent a call in progress being dropped before said handoff, said method comprising the steps of:
A call handoff apparatus in a cellular mobile radiotelephone system having a plurality of cells each providing radio coverage by a base station and having a plurality of mobile stations each associated with one of said cells, said apparatus comprising:
In a cellular mobile radiotelephone system, a method of call handoff comprising the steps of:
In a cellular mobile radio system including a mobile station and number of base stations each serving a specific service area, said base stations including a communicating base station communicating call information with said mobile station and serving one area and a neighboring base station serving another area, wherein said one area and a neighboring area have a common area in which communications both between the communicating base station and the mobile station and between the neighboring base station and the mobile station have sufficient signal level, a method of locating said mobile station in the system, comprising the steps of:
In a cellular mobile radio system including a mobile station and number of base stations each serving a specific service area, said base stations including a communicating base station communicating call information with said mobile station and serving one area and a neighboring base station serving another area, said communicating base station serving said one area with a lower radio signal power than said neighboring base station serves said another area with said one area and said another area having a common area in which communications both between the communicating base station and the mobile station and between the neighboring base station and the mobile station have sufficient signal level, a method of locating said mobile station in the system, comprising the steps of:
A cell handoff method in a cellular mobile radio telephone system having a plurality of cell sites and a mobile station, comprising the steps of:
Dependencies are inferred from the claim text.