A radio unit, comprising: an antenna calibrator configured to generate a plurality of individually identifiable reference signals used for transmission calibration of antenna branches, the antenna branches formed by a plurality of transmission signal processing sections configured to modulate the signals in parallel; a plurality of power amplifiers configured to amplify the modulated signals to predetermined power levels in parallel; a plurality of bandpass filters configured to apply bandpass filtering operations to the modulated signals in parallel; the radio unit further comprising a plurality of couplers configured to couple the filtered signals to a first combiner which combines the filtered signals; a plurality of reception signal processing sections, one of which is configured to identify and demodulate each of the filtered signals constituting the combined signals; and a Voltage Standing Wave Ratio (VSWR) measurement unit, a first plurality of switches (SW_F1, SW_F2, SW_F3, SW_F4) connected between the first combiner and the couplers, a second combiner and a second plurality of switches (SW_R1, SW_R2, SW_R3, SW_R4) connected between the second combiner and the couplers, wherein the voltage standing wave ratio measurement unit is connected to the first and second combiners and wherein the antenna calibrator is further configured to compute transmission calibration vectors by comparing the demodulated signals with the reference signals, and forward powers for the respective antenna branches are respectively sent back to the first plurality of switches (SW_F1, SW_F2, SW_F3, SW_F4), and reflected powers for respective antenna branches are respectively sent back to the second plurality of switches (SW_R1, SW_R2, SW_R3, SW_R4); and in a case where VSWR measurement is performed for one antenna branch, only a corresponding one of the first switches (SW_F1, SW_F2, SW_F3, SW_F4) and a corresponding one of the second switches (SW_R1, SW_R2, SW_R3, SW_R4) are closed, so that a corresponding one of the forward powers is selected by the first combiner and a corresponding one of the reflected powers is selected by the second combiner; and the VSWR measurement unit is configured to compute the VSWR for the antenna branch based on the selected forward power and reflected power. an antenna calibrator configured to generate a plurality of individually identifiable reference signals used for transmission calibration of antenna branches, the antenna branches formed by a plurality of transmission signal processing sections configured to modulate the signals in parallel; a plurality of power amplifiers configured to amplify the modulated signals to predetermined power levels in parallel; a plurality of bandpass filters configured to apply bandpass filtering operations to the modulated signals in parallel; the radio unit further comprising a plurality of couplers configured to couple the filtered signals to a first combiner which combines the filtered signals; a plurality of reception signal processing sections, one of which is configured to identify and demodulate each of the filtered signals constituting the combined signals; and a Voltage Standing Wave Ratio (VSWR) measurement unit, a first plurality of switches (SW_F1, SW_F2, SW_F3, SW_F4) connected between the first combiner and the couplers, a second combiner and a second plurality of switches (SW_R1, SW_R2, SW_R3, SW_R4) connected between the second combiner and the couplers, wherein the voltage standing wave ratio measurement unit is connected to the first and second combiners and wherein the antenna calibrator is further configured to compute transmission calibration vectors by comparing the demodulated signals with the reference signals, and forward powers for the respective antenna branches are respectively sent back to the first plurality of switches (SW_F1, SW_F2, SW_F3, SW_F4), and reflected powers for respective antenna branches are respectively sent back to the second plurality of switches (SW_R1, SW_R2, SW_R3, SW_R4); and in a case where VSWR measurement is performed for one antenna branch, only a corresponding one of the first switches (SW_F1, SW_F2, SW_F3, SW_F4) and a corresponding one of the second switches (SW_R1, SW_R2, SW_R3, SW_R4) are closed, so that a corresponding one of the forward powers is selected by the first combiner and a corresponding one of the reflected powers is selected by the second combiner; and the VSWR measurement unit is configured to compute the VSWR for the antenna branch based on the selected forward power and reflected power.