초록 ▼

If the strength of the signal transmitted from a remaining base station is larger than that from the active base station, the search control unit 103 shifts to the confirmation mode, where the remaining base station is designated as a confirmation target remaining base station. Then, if the strength

If the strength of the signal transmitted from a remaining base station is larger than that from the active base station, the search control unit 103 shifts to the confirmation mode, where the remaining base station is designated as a confirmation target remaining base station. Then, if the strength of the signal transmitted from the confirmation target remaining base station is larger than that from the active base station, a counter is incremented. If the counter value becomes a predetermined value R, a hand-off is performed to the remaining base station. In case that the strength of the signal transmitted from the confirmation target remaining base station becomes not larger than that from the active base station, the confirmation mode is terminated at that point to return to the normal mode.

대표청구항 ▼

1. A mobile station for a CDMA communication system comprising:a detecting means for detecting strengths of signals transmitted from a plurality of base stations; a finding means for finding a first base station transmitting a signal having a larger signal strength than a signal from a second base s

1. A mobile station for a CDMA communication system comprising:a detecting means for detecting strengths of signals transmitted from a plurality of base stations; a finding means for finding a first base station transmitting a signal having a larger signal strength than a signal from a second base station with which the mobile station is currently in communication; a judging means for judging whether the found base station by the finding means is one of neighbor base stations located in the vicinity of the second base station or one of remaining base stations other than the neighbor base stations; and a hand-off control means for, if the found base station is one of the remaining base stations, designating the remaining base station as a confirmation target remaining base station and temporarily suspending a hand-off to the confirmation target remaining base station. 2. The mobile station for the CDMA communication system according to claim 1,wherein the hand-off control means makes the detecting means repeatedly detect a strength of a signal transmitted from the confirmation target remaining base station, while suspending the hand-off temporarily, and cancels the suspension so that the hand-off is performed to the confirmation target remaining base station, if a number of times when the strength of the signal transmitted from the confirmation target remaining base station is consecutively larger than the strength of the signal transmitted from the second base station reaches a predetermined number. 3. The mobile station for the CDMA communication system according to claim 2,wherein the hand-off control means further makes the detecting means detect strengths of the signals transmitted from the neighbor base stations during intervals between each detection of the strength of the signal transmitted from the confirmation target remaining base station, and if a strength of a signal transmitted from one of the neighbor base stations is larger than the strength of the signal transmitted from the second base station, the hand-off control means hands off to the neighbor base station. 4. The mobile station for the CDMA communication system according to claim 3,wherein the hand-off control means controls the detecting means so that a frequency of detecting the strengths of the signals transmitted from the neighbor base stations is higher than a frequency of detecting the strength of the signal transmitted from the confirmation target remaining base station. 5. The mobile station for the CDMA communication system according to claim 4,wherein the hand-off control means, if a hand-off is performed to one of the neighbor base stations, controls the detecting means so that detection of the strength of the signal transmitted from the confirmation target remaining base station is antecedent to detection of strengths of signals transmitted from other remaining base stations. 6. The mobile station for the CDMA communication system according to claim 1,wherein the hand-off control means makes the detecting means detect a strength of a signal transmitted from the confirmation target remaining base station a predetermined number of times, while suspending the hand-off temporarily, and cancels the suspension so that the hand-off is performed to the confirmation target remaining base station if a mean value of strengths of the signals transmitted from the confirmation target remaining base station detected by the detecting means the predetermined number of times is larger than the strength of the signal transmitted from the second base station. 7. The mobile station for the CDMA communication system according to claim 6,wherein the hand-off control means further makes the detecting means detect strengths of the signals transmitted from the neighbor base stations during intervals between each detection of the strength of the signal transmitted from the confirmation target remaining base station, and if a strength of a signal transmitted from one of the neighbor base stations is larger than the strength of the signal transmitted from the second base station, the hand-off control means hands off to the neighbor base station. 8. The mobile station for the CDMA communication system according to claim 7,wherein the hand-off control means controls the detecting means so that a frequency of detecting the strengths of the signals transmitted from the neighbor base stations is higher than a frequency of detecting the strength of the signal transmitted from the confirmation target remaining base station. 9. The mobile station for the CDMA communication system according to claim 8,wherein the hand-off control means, if a hand-off is performed to one of the neighbor base stations, controls the detecting means so that detection of the strength of the signal transmitted from the confirmation target remaining base station is antecedent to detection of strengths of signals transmitted from other remaining base stations. 10. The mobile station for the CDMA communication system according to claim 1,wherein the hand-off control means makes the detecting means detect a strength of a signal transmitted from the confirmation target remaining base station a predetermined number of times, while suspending the hand-off temporarily, and cancels the suspension so that the hand-off is performed to the confirmation target remaining base station if a ratio of a number of times when the strength of the signal transmitted from the confirmation target remaining base station is larger than the strength of the signal transmitted from the second base station to the predetermined number of times is a predetermined ratio or higher. 11. The mobile station for the CDMA communication system according to claim 10,wherein the hand-off control means further makes the detecting means detect strengths of the signals transmitted from the neighbor base stations during intervals between each detection of the strength of the signal transmitted from the confirmation target remaining base station, and if a strength of a signal transmitted from one of the neighbor base stations is larger than the strength of the signal transmitted from the second base station, the hand-off control means hands off to the neighbor base station. 12. The mobile station for the CDMA communication system according to claim 11,wherein the hand-off control means controls the detecting means so that a frequency of detecting the strengths of the signals transmitted from the neighbor base stations is higher than a frequency of detecting the strength of the signal transmitted from the confirmation target remaining base station. 13. The mobile station for the CDMA communication system according to claim 12,wherein the hand-off control means, if a hand-off is performed to one of the neighbor base stations, controls the detecting means so that detection of the strength of the signal transmitted from the confirmation target remaining base station is antecedent to detection of strengths of signals transmitted from other remaining base stations. 14. A method for communication used in a mobile station for a CDMA communication system comprising:a detecting step for detecting strengths of signals transmitted from a plurality of base stations; a finding step for finding a first base station transmitting a signal having a larger signal strength than a signal from a second base station with which the mobile station is currently in communication; a judging step for judging whether the found base station in the finding step is one of neighbor base stations located in the vicinity of the second base station or one of remaining base stations other than the neighbor base stations; and a hand-off control step for, if the found base station is one of the remaining base stations, designating the remaining base station as a confirmation target remaining base station and temporarily suspending a hand-off to the confirmation target remaining base station. 15. The method for communication of the mobile station for the CDMA communication system according to claim 14, comprising an additional step of:detecting a strength of a signal transmitted from the confirmation target remaining base station repeatedly, while continuing the suspension of the hand-off temporarily after the hand-off control step and canceling the suspension so that the hand-off is performed to the confirmation target remaining base station if a number of times when the strength of the signal transmitted from the confirmation target remaining base station is consecutively larger than the second base station reaches a predetermined number. 16. The method for communication of the mobile station for the CDMA communication system according to claim 14, comprising an additional step of:detecting a strength of a signal transmitted from the confirmation target remaining base station a predetermined number of times, while continuing the suspension of the hand-off temporarily after the hand-off control step and canceling the suspension so that the hand-off is performed to the confirmation target remaining base station if a mean value of strengths of signals transmitted from the confirmation target remaining base station detected the predetermined number of times is larger than the second base station. 17. The method for communication of the mobile station for the CDMA communication system according to claim 14, comprising the additional steps of:detecting a strength of a signal transmitted from the confirmation target remaining base station a predetermined number of times, while continuing the suspension of the hand-off temporarily after the hand-off control step; and canceling the suspension and performing the hand-off to the confirmation target remaining base station if a ratio of a number of times when the strength of the signal transmitted from the confirmation target remaining base station is larger than the strength of the signal transmitted from the second base station to the predetermined number of times is a predetermined ratio or higher.