초록 ▼

The invention relates to a method for improving the reliability of a handover and call establishment in a cellular radio system which comprises at least one base station in each cell, and a group of subscriber terminal equipments which communicate with one or more base stations. The base stations me

The invention relates to a method for improving the reliability of a handover and call establishment in a cellular radio system which comprises at least one base station in each cell, and a group of subscriber terminal equipments which communicate with one or more base stations. The base stations measure the total interference level of signals they have received from the terminal equipments, and transmit a pilot signal with a known transmit power. The terminal equipments measure the power levels of pilot signals received from different base stations. In the system at least some transceivers comprise circuitry for estimating, by means of the pilot signals, the path loss between the terminal equipment and the base stations. To improve the reliability of the handover and call establishment, at least some transceivers in the system of the invention estimate the signal to noise ratio between the terminal equipment and the base station in the uplink transmission direction on the basis of the total interference measured at the base station, the path loss, and the terminal equipment transmit power.

대표청구항 ▼

[ We claim:] [1.] A method for improving the reliability of a handover in a cellular radio system which comprises at least one base station in each cell, and a group of subscriber terminal equipments which communicate with one or more base stations, comprising steps of:measuring at a base station a

[ We claim:] [1.] A method for improving the reliability of a handover in a cellular radio system which comprises at least one base station in each cell, and a group of subscriber terminal equipments which communicate with one or more base stations, comprising steps of:measuring at a base station a total interference level of signals received from the terminal equipments, andtransmitting a pilot signal with a known transmit power,measuring at a subscriber terminal equipment, in order to determine the need for a handover, the power levels of pilot signals received from those base stations which are on a terminal equipment maintained list of near-by base stations, and in whicha path loss between the terminal equipment and the base stations is estimated by means of the received pilot signals,wherein the signal to noise ratio between the terminal equipment and the base station in the transmission direction from the terminal equipment to the base station is estimated on the basis of the total interference measured at the base station, the path loss, and the terminal equipment transmit power, and whereinthe list maintained by each subscriber terminal equipment of near-by base stations is updated on the basis of said estimate.