Patent ID: 9667372
Date: 2017-05-30
CPC Classifications: H04B,H04J,H04L,H04W

Claim:
1. A mobile communication terminal for receiving a downlink signal from a desired base station by an orthogonal frequency-division multiple access, the mobile communication terminal comprising: a plurality of reception antennas for receiving radio waves; a reference signal vector measurer configured to measure a reference signal vector being a vector representing a reference signal transmitted from the desired base station; an interference rejection combining processor configured to calculate an interference rejection combining reception weight matrix based on the reference signal vector measured by the reference signal vector measurer so as to reduce effects on a desired beam by another beam, wherein the desired beam is a beam of radio waves transmitted from the desired base station; an all received power estimator configured to estimate an all received power expected when an interference rejection combining is implemented, the all received power being estimated from the interference rejection combining reception weight matrix and the reference signal vector measured by the reference signal vector measurer; a channel impulse matrix estimator configured to estimate a channel impulse matrix from a signal derived from the radio waves received by the reception antennas; a desired reference signal power estimator configured to estimate a desired reference signal power expected when the interference rejection combining is implemented, the desired reference signal power being estimated from an interference rejection combining weight vector being a part of the interference rejection combining reception weight matrix, the channel impulse matrix, and a reference signal sequence being a sequence of the reference signal or of another reference signal; an interference and noise power estimator configured to estimate an interference and noise power expected when the interference rejection combining is implemented, the interference and noise power being estimated by subtracting the desired reference signal power from the all received power; a transmission weight vector estimator configured to estimate a transmission weight vector, from the channel impulse matrix, to be used for precoding performed at the desired base station; a desired data signal power estimator configured to estimate a desired data signal power expected when the interference rejection combining is implemented, the desired data signal power being estimated from the interference rejection combining weight vector, the channel impulse matrix, and the transmission weight vector; and a signal-to-interference-plus-noise ratio calculator configured to calculate a signal-to-interference-plus-noise ratio expected when the interference rejection combining is implemented, the signal-to-interference-plus-noise ratio being calculated from the desired data signal power and the interference and noise power.