A full-duplex optical data link using lasers as transceivers

We present an optical-data link that uses the simplest possible optical components-a laser at each end serves as both the light source and detector. A laser cannot transmit and detect light simultaneously, therefore, we use low-duty-cycle pulses, where one laser derives its clock from the signal it receives from the other laser. By interweaving the bits, and careful choice of pulse length, each laser is able to separate transmitted from received signals. We have transmitted 1 Mb/s data over 12 km of fiber with a BER<10/sup -9/. To our knowledge, this "proof of concept" demonstration is the first to use commercial Fabry-Perot lasers as transceivers in a full-duplex system.<>