4-phase p.s.k. differential demodulator using a.s.w. delay lines

The letter describes a cheap and reliable solution, using acousticsurface-wave delay lines, for the differential demodulation of phase-shift-keyed digital signals at low digital rates (up to 20 Mbit/s). Results on 4-phase p.s.k. differential demodulators operating at 2.048 Mbit/s are reported in terms of bit error rate against energy per bit/noise spectral density ratio. In addition, using the same technology, a new multidifferential demodulator has been implemented. Owing to multiple differential demodulations carried out on the same signal, a significant improvement in both theoretical and experimental bit error rate is obtained.