The present disclosure relates to a front-end system for a radio device. In one example, a front-end system comprises a converter, the converter comprising a mixer configured for down-converting a radio frequency signal into a baseband signal by using a local oscillator signal generated by a signal generator, and characterized in that, the converter further comprises a quantizer arranged for quantizing the baseband signal into a digital signal. Further, the signal generator may be configured for generating, based on the digital signal, the local oscillator signal such that it is synchronized with the radio frequency signal.