Patent ID: 7634288

Claim:
A mobile communication system which controls downlink transmission power of a base station in accordance with a power control bit from a mobile communication terminal, wherein the mobile communication terminal includes determination means for determining whether downlink transmission power of the base station complies with the power control bit transmitted from the mobile communication terminal, based on a correspondence between (a) past power control bits that were transmitted by the mobile communication terminal and (b) changes in reception levels from the base station at respective times corresponding to the transmission of the past power control bits, wherein if a plurality of base stations are controlling downlink transmission power in accordance with power control bits, the mobile communication terminal combines only reception data from said plurality of base stations and then checks the reception quality, the mobile communications terminal controlling base station downlink transmission power based on said reception quality, and wherein said determination means includes pattern storage means for storing each Up/Down/Hold pattern in a past power control bit transmitted from the mobile communication terminal, reception level change storage means for storing a change in reception level from the base station which is synchronous with a timing of each of the power control bits, and comparison means for comparing a pattern in said pattern storage means with a change in reception level in said reception level change storage means, determines that the base station is controlling the downlink transmission power in accordance with the power control bit, when the pattern coincides with the change in reception level, and determines that the base station is not controlling the downlink transmission power in accordance with the power control bit, when the pattern does not coincide with the change in reception level.