A Simple DBPSK Modem Based on High-Speed Logical Gates for a 70/80 GHz GbE Microwave Link

A simple DBPSK modulator and demodulator based on high-speed logical gates is implemented. The modulator and demodulator is verified in a GbE microwave link for the 70/80 GHz band. Performance is evaluated back-to-back and in an outdoor hop over 1 km. The authors also show how the scheme may be extended to support the DQPSK format and thus double the capacity further. The mobile backhaul network is the most important commercial application for point-to-point microwave links with a global installed base exceeding three million devices. However, with the roll-out of next generation, radio access technologies (e.g. HSPA+, LTE rel. 8, LTE rel. 10 and beyond) the backhaul network needs increased capacity.