Applications of SAW technology in a SONET-compatible high capacity digital microwave radio

Surface acoustic wave (SAW) technology is used in the development of the world's first SONET-compatible digital microwave radio system. The SONET Radio 440 utilizes a 512 quadrature AM (QAM) modulation scheme to transport an OC-12 (622 Mbit) data stream over two 40 MHz channels, achieving twice the efficiency of current long-haul digital microwave radio systems. The success of this radio is due largely to the application of SAW technology in the signal processing hardware. Pulse shaping filters have been developed to provide stringent out-of-band rejection while maintaining the channel fidelity necessary for the high modulation scheme. Antenna delay differences are equalized from a terminal, thus simplifying the setup of a system in the field.< >