The present general inventive concept relates to apparatuses and/or methods for measuring an in-phase and quadrature (IQ) imbalance. In one embodiment, a detector can measure an error caused by an IQ imbalance using a first IQ signal including a desired signal and a corresponding image signal by the IQ imbalance. The detector can include a derotator to derotate the first IQ signal by a first angular frequency to obtain a second IQ signal and derotate the first IQ signal by a second angular frequency to obtain a third IQ signal, a DC estimator to obtain a fourth IQ signal corresponding to a DC component of the second IQ signal and a fifth IQ signal corresponding to a DC component of the third IQ signal and a controller can determine a gain error or a phase error from the fourth IQ signal and the fifth IQ signal.