Patent ID: 9173113
Filing Date: 2015-10-27
Classification: H04B,H04L,H04W

Abstract:
1. A mobile communication terminal for receiving downlink signals from a desired base station by orthogonal frequency division multiple access, comprising: multiple receiving antennas for receiving electric waves; an interference rejection combining processor adapted for obtaining a received signal vector with regard to each of multiple resource elements from signals derived from electric waves received by the multiple receiving antennas, and adapted for calculating receiving weights so as to suppress influence to a desired beam of electric wave sent from the desired base station by other beams, on the basis of the received signal vectors; a non-interference-rejection receiving weight calculator adapted for calculating receiving weights so as not to suppress influence to the desired beam of electric wave sent from the desired base station by other beams; a signal separator adapted for separating a signal destined for the mobile communication terminal from signals destined for other mobile communication terminals among signals derived from electric waves received at the multiple receiving antennas; an interference rejection combining determiner adapted for determining whether the receiving weights calculated by the interference rejection combining processor or the receiving weights calculated by the non-interference-rejection receiving weight calculator should be used for signal separation by the signal separator, on the basis of an index representing a relationship between reception quality of a downlink transmission signal from the desired base station to the mobile communication terminal and reception quality of an interfering signal sent from another base station and received by the mobile communication terminal, a reception quality measurer adapted for measuring reception qualities of signals sent from different base stations and received by the mobile communication terminal in order to facilitate searching the desired base station to which the mobile communication terminal should connect; and a quality ratio calculator adapted for calculating a ratio of a reception quality of a signal from the desired base station measured by the reception quality measurer to a reception quality of a signal from another base station measured by the reception quality measurer, wherein the interference rejection combining determiner is adapted for comparing the ratio calculated by the quality ratio calculator with a threshold, for determining that the receiving weights calculated by the interference rejection combining processor should be used for signal separation by the signal separator if the ratio is less than the threshold, and for determining that the receiving weights calculated by the non-interference-rejection receiving weight calculator should be used for signal separation by the signal separator, instead of the receiving weights calculated by the interference rejection combining processor, if the ratio is greater than the threshold.