| 摘要 |
<p>A transmitter comprises an orthogonal modulator that quadrature-modulates a carrier wave with an input signal containing a common-mode signal component and an orthogonal signal component and outputs the modulated signal to be transmitted, a detecting means that detects a carrier leakage component contained in the modulated signal, a DC offset value-calculating means that calculates a DC offset value to be added to the input signal according to the carrier leakage component to compensate for the carrier leakage component, and an abnormality-judging means that judges whether or not the quadrature modulator is normal according to the DC offset value. By monitoring the DC offset value, a failure or a sign of a failure of the quadrature modulator can be detected, which prevents an abnormal modulated signal containing a distortion component from being transmitted. That is, the quality degradation of adjacent radio communication lines due to an increase of power leakage to the adjacent channels can be prevented.</p> |
