A complex intermediate frequency mixer (IFM) for frequency translating a received complex intermediate frequency, IF, signal, wherein the received complex IF signal comprises at least two frequency bands located at upper-side and lower-side of 0 Hz, is provided. The complex intermediate frequency mixer comprises a first, second, third and fourth mixer (M1, M2, M3, M4). The complex intermediate frequency mixer further comprises a first, second, third and fourth gain adjusting component (α1, α2, δ2, δ1), connected to a first, second, third and fourth mixer output (M1-out, M2-out, M3-out, M4-out), respectively. Moreover, a first summing unit (S1), connected to a first gain output (α1-out), a fourth gain output (δ1-out) and a third mixer output (M3-out) negated, and second summing unit (S2), connected to the second gain output (α2-out), the third gain output (δ2-out) and the fourth mixer output (M4-out), are configured to output a first baseband complex signal of the received complex IF signal.