A reception device comprising: a reception unit to receive a plurality of transmission signals via propagation paths (30a, 30b) orthogonal to each other, the transmission signals being obtained by multiplexing a plurality of first signals by using a real precoding matrix, the fist signals being L, where L is an integer of 2 or larger, complex baseband signals whose real component and imaginary component are modulated independently of each other; a splitting unit to split each of a plurality of received signals received by the reception unit into a real component and an imaginary component; a narrowing unit (221a, 221b) to narrow down possible signal point candidates of a real component of the first signal to signal point candidates on a basis of the real component of the split received signal and narrow down possible signal point candidates of an imaginary component of the first signal to signal point candidates on a basis of the imaginary component of the split received signal; a signal point candidate hypothesizing unit (223a to 223f) to hypothesize one signal point candidate of a real component from the signal point candidates of a real component obtained by the narrowing down and hypothesize one signal point candidate of an imaginary component from the signal point candidates of an imaginary component obtained by the narrowing down; and a signal estimation value calculating unit (224a to 224f) to estimate a real component of the first signal on a basis of the one hypothesized real component signal point candidate and estimate an imaginary component of the first signal on a basis of the one hypothesized imaginary component signal point candidate, characterized in that the first signals are modulated by a 2 2N -QAM, Quadrature Amplitude Modulation, technique, where N is an integer of 2 or larger, and the narrowing unit (221a, 221b) selects, from among possible signal point candidates of the first signal, a signal point candidate that is closest to a signal point of the received signal and a signal point candidate that is closest to the received signal in each inverted bit among signal point candidates including an inverted bit with respect to each bit of the closest signal point candidate, and outputs the selected signal point candidates. a reception unit to receive a plurality of transmission signals via propagation paths (30a, 30b) orthogonal to each other, the transmission signals being obtained by multiplexing a plurality of first signals by using a real precoding matrix, the fist signals being L, where L is an integer of 2 or larger, complex baseband signals whose real component and imaginary component are modulated independently of each other; a splitting unit to split each of a plurality of received signals received by the reception unit into a real component and an imaginary component; a narrowing unit (221a, 221b) to narrow down possible signal point candidates of a real component of the first signal to signal point candidates on a basis of the real component of the split received signal and narrow down possible signal point candidates of an imaginary component of the first signal to signal point candidates on a basis of the imaginary component of the split received signal; a signal point candidate hypothesizing unit (223a to 223f) to hypothesize one signal point candidate of a real component from the signal point candidates of a real component obtained by the narrowing down and hypothesize one signal point candidate of an imaginary component from the signal point candidates of an imaginary component obtained by the narrowing down; and a signal estimation value calculating unit (224a to 224f) to estimate a real component of the first signal on a basis of the one hypothesized real component signal point candidate and estimate an imaginary component of the first signal on a basis of the one hypothesized imaginary component signal point candidate, characterized in that the first signals are modulated by a 2 2N -QAM, Quadrature Amplitude Modulation, technique, where N is an integer of 2 or larger, and the narrowing unit (221a, 221b) selects, from among possible signal point candidates of the first signal, a signal point candidate that is closest to a signal point of the received signal and a signal point candidate that is closest to the received signal in each inverted bit among signal point candidates including an inverted bit with respect to each bit of the closest signal point candidate, and outputs the selected signal point candidates.