| 摘要 |
<p>A method and circuit are presented for the all optical recovery of the clock signal from an arbitrary optical data signal. The method involves two stages. A first stage (150) preprocesses the optical signal by converting a NRZ signal to a PRZ signal, or if the input optical signal (100) is RZ, by merely amplifying it. In a preferred embodiment this stage is implemented via an integrated SOA in each arm (105, 106) of an asymmetric interferometric device. The output (103) of the processing stage is fed to a clock recovery stage (160), which consists of a symmetric interferometer that locks on to the inherent clock signal by using the second stage input signal to trigger two optical sources (113, 114) to self oscillate at the clock rate. In a preferred embodiment the second stage is implemented via SOAs integrated in the arms (111, 112) of an interferometer, with two DFB lasers (113, 114) as terminuses. The output (115) of the interferometer is an optical clock signal at the clock rate of the original input.</p> |
