A 10-Gb/s optical asynchronous packet receiver with a fast bit-synchronization circuit

A novel 10-Gb/s fast acquisition bit-synchronization circuit for use in a Tb/s throughput optical packet switch has been developed. The circuit is a best-sampled data-select type based on multiple phase-clocks, and it processes the asynchronous input packets into a synchronous data stream in a serial manner, which is advantageous in terms of circuit scale and consumption power compared with the parallel processing type. The circuit was developed using Si-bipolar ultrahigh-speed gate arrays and it was used to develop a 10-Gb/s optical asynchronous packet receiver module. The core logic of this circuit module:required about 100 gates, consume 6 W, and the size of the module was reduced to only 170 mm (W) x 130 mm (D) x 10 mm (H). Using the receiver module, a fast acquisition time of 9 bits and receiver sensitivity penalty of less than 1.5 dB due to re-synchronization were measured.