Method for calibrating an SSB receiver

A method for calibrating a single sideband (SSB) receiver having an input for receiving a signal, an I/Q mixer for converting the signal into an I-signal in an inphase path and a Q-signal in a quadrature path, a phase shifter for mutually phase shifting the I- and Q-signals by an adjustable phase shift, and a combiner for combining the mutually phase shifted I- and Q-signals to an SSB signal, the method comprising:

• a) adjusting the phase shift to a first phase shift value;
• b) successively feeding a first, a second and a third test signal to the input, the first and second test signals having a predetermined phase offset and the second and third test signals having the same predetermined phase offset, to obtain respective first, second and third SSB signals, and measuring a first phase difference between the first and second SSB signals and a second phase difference between the second and third SSB signals;
• c) calculating a first phase error on the basis of the first and second phase differences;
• d) repeating steps a)-c) with a second phase shift value in step a) to obtain a second phase error;
• and
• e) calibrating the SSB receiver by using that one of the first and second phase shift values that has yielded the smaller one of the first and second phase errors.