A system-on-package analog synchronous QPSK demodulator for ultra-high rate 60 GHz wireless communications

A highly efficient QPSK demodulator module is presented, which synchronizes carrier phase and frequency in the analog domain by feed-forward carrier recovery. By this, the need for high-precision ADCs is eliminated, which become especially problematic for data rates exceeding several Gbit/s. The QPSK demodulator is realized as a SiGe HBT MMIC and is packaged on a standard low cost substrate material, where a narrow-bandwidth microstrip bandpass filter is also integrated. Synchronous demodulation of up to 5 Gbit/s data rate is demonstrated. Moreover, it is experimentally validated that through the presented feed-forward carrier recovery a substantial amount of phase noise suppression can be achieved.