초록 ▼

The invention relates to a method for communication and handoff in a cellular mobile radio system and a base station and a mobile station for communication and handoff in such a system, in which time slot identifier codes are transmitted in bursts in times slots in frames of radio channels used for

The invention relates to a method for communication and handoff in a cellular mobile radio system and a base station and a mobile station for communication and handoff in such a system, in which time slot identifier codes are transmitted in bursts in times slots in frames of radio channels used for time division communication channels, the time slot identified codes being indicative of burst time slot in a frame but not of transmitter or receiver entity or radio channel, the time slot identifier codes being used for burst synchronization and determining bursts the signal strength of which to be measured for the purpose of possible handoff.

대표청구항 ▼

A method of communication and handoff in a cellular mobile radio system comprising a plurality of base stations, a plurality of mobile stations and a plurality of radio channels, at least two of the radio channels being used for digital communication channels by transmission of digitally modulated r

A method of communication and handoff in a cellular mobile radio system comprising a plurality of base stations, a plurality of mobile stations and a plurality of radio channels, at least two of the radio channels being used for digital communication channels by transmission of digitally modulated radio signals on the radio channels, at least two of the digital communication channels sharing a common radio channel in time division multiplexing, at least two of the radio channels being used for control channels by transmission of radio signals modulated with control information on the radio channels, the method comprising the steps of: transmitting, to a particular mobile station from a base station responsible for the communication with the particular mobile station at setup of a connection on a digital communication channel and at handoff of a connection to a digital communication channel, information on a particular time slot identifier code and a plurality of selected radio channels; transmitting, from the particular mobile station, the particular time slot identifier code with radio signals in each time slot of the digital communication channel of the connection during the connection; measuring, at the particular mobile station, the strength of radio signals received on the selected radio channels and the signal strength on the digital communication channel used for the connection of the mobile station; transmitting repeatedly from the particular mobile station to the responsible base station results of measurements of signal strength at the particular mobile station; measuring, at the base station responsible for the communication with the particular mobile station, the signal strength on the digital communication channel used for the connection of the mobile station; processing and analyzing the results of the measurements done at the responsible base station and the received results from the particular mobile station and comparing with criteria for handoff; determining a target base station assumed suitable for the communication with the particular mobile station when, according to the processing and analyzing and comparing, a handoff needs to be done; supplying the target base station with information on the radio channel and the time slot identifier code of the digital communication channel of the established connection of the particular mobile station and requesting the target base station to measure signal strength on the digital communication channel; using the supplied information on the radio channel and the time slot identifier code at the target base station for finding the digital communication channel of the established connection of the particular mobile station and measuring signal strength on the digital communication channel; reporting from the target base station the measurement of signal strength on the digital communication channel; deciding whether the handoff shall be performed in view of a report from the target base station and informing the target base station on the particular mobile station when the handoff shall be performed and what radio channel and time slot identifier code is to be used by the particular mobile station for the established connection after the handoff; after receiving at the particular mobile station information that handoff shall be performed, using the time slot identifier code at the particular mobile station to find the correct time slots and transmitting from the particular mobile station radio signals comprising the time slot identifier code on the radio channel; and after receiving at the target base station information that a handoff shall be performed and information on the radio channel and the time slot identifier to be used by the particular mobil station, checking at the target base station for the appearance of radio signals comprising the time slot identifier code on the radio channel.