Method and system for switching radio frequency

Claim 1

A system having a plurality of base stations and a plurality of mobile stations, each of said base stations comprising: means for time-divisionally transmitting data at a frequency assigned thereto, different frequencies being assigned to said base stations, respectively, said data including first information identifying one of said mobile stations and second information indicating a time of which a next data transmission to be received by the identified mobile stations starts, each of said mobile stations comprising: means for receiving data transmitted from other base stations; means for measuring the reception electric field of said given and other base stations to select among said given and other base stations a base station transmitting the highest electric field; and switching request means for transmitting a switching request to the selected base station, so that the reception frequency of the mobile station is switched to a frequency assigned to said selected base station.

Claim 2

A system having a plurality of base stations and a plurality of mobile stations, each of said base stations comprising: means for time-divisionally transmitting data at a frequency assigned thereto, different frequencies being assigned to said base stations, respectively, said data including first information identifying one of said mobile stations and second information indicating a time of which a next data transmission to be received by the identified mobile stations starts, each of said mobile stations comprising: means for receiving data transmitted from other base stations; means for measuring the reception electric field of said given and other base stations to select among said given and other base stations a base station transmitting the highest electric field; and switching request means for transmitting a switching request to the selected base station, so that the reception frequency of the mobile station is switched to a frequency assigned to said selected base station.

Claim 4

A method of switching a first frequency of a mobile subscriber unit to another frequency, comprising the following steps: time-divisionally transmitting data from a plurality of base stations at a plurality of different frequencies, respectively, said plurality of frequencies corresponding to said plurality of base stations, respectively, and including said first frequency; changing said first frequency of said mobile subscriber unit to other frequencies during a time period in which no data is addressed to said mobile subscriber unit; measuring at said mobile subscriber unit the reception conditions of said first and other frequencies to produce measured reception conditions, respectively; and based on said measured reception conditions, selecting an optimal frequency among said first and other frequencies in order to switch said first frequency of said mobile subscriber unit to said optimal frequency.

Claim 5

A method of switching a first frequency of a mobile subscriber unit to another frequency, comprising the following steps: time-divisionally transmitting data from a plurality of base stations at a plurality of different frequencies, respectively, said plurality of frequencies corresponding to said plurality of base stations, respectively, and including said first frequency; changing said first frequency of said mobile subscriber unit to other frequencies during a time period in which no data is addressed to said mobile subscriber unit; measuring at said mobile subscriber unit the reception conditions of said first and other frequencies to produce measured reception conditions, respectively; and based on said measured reception conditions, selecting an optimal frequency among said first and other frequencies in order to switch said first frequency of said mobile subscriber unit to said optimal frequency.

Claim 7

A system in which data is time-divisionally transmitted from a plurality of base stations to a plurality of mobile subscribers at different frequencies corresponding to said base stations, wherein each of said mobile subscribers comprises: monitor means for determining when data is not transmitted from the base station; discriminating means for discriminating a base station corresponding to the highest reception electric field when said monitoring means determines that no data is transmitted; and means for transmitting a request for switching a reception frequency to that of the discriminated frequency to the discriminated base station.

Claim 8

A system in which data is time-divisionally transmitted from a plurality of base stations to a plurality of mobile subscribers at different frequencies corresponding to said base stations, wherein each of said mobile subscribers comprises: monitor means for determining when data is not transmitted from the base station; discriminating means for discriminating a base station corresponding to the highest reception electric field when said monitoring means determines that no data is transmitted; and means for transmitting a request for switching a reception frequency to that of the discriminated frequency to the discriminated base station.