A method for determining an image rejection characteristic of a receiver within a transceiver is provided. The transceiver uses a common local oscillator. The method includes generating a test signal having a spectral peak and generating a local oscillator signal comprising a frequency with an offset from a center frequency of the spectral peak. Further, the method includes down-mixing the test signal in the receiver using the local oscillator signal to generate a down-mixed signal. The method further includes calculating a first value of a signal characteristic of the down-mixed signal in a first frequency range corresponding to a desired signal component of the down-mixed signal and calculating a second value of the signal characteristic of the down-mixed signal in a second frequency range corresponding to an undesired signal component of the down-mixed signal. Further, the method includes comparing the first value and the second value to generate the image rejection characteristic.