GaAs integrated circuits for error-rate measurement in high-speed digital transmission systems

A high-speed GaAs MSI PRBS generator and an error detector have been built, tested, and applied to bit-error ratio measurements in a fiber-optic transmission link. The generator produces a 1023 bit sequence at 2 Gbit/s data rate. The detector compares, bit-by-bit, the input data with a locally regenerated sequence. With a 2 GHz clock, the direct-coupled generator/detector combination, without an optical link, exhibits less than one error in 10/SUP 14/ clock cycles. The complete fiber-optic link test system incorporates a 1 km multimode fiber, operates at 1.9 Gbits/s, and exhibits a bit-error ratio below 10/SUP -12/.