Bit-rate detection circuit for rapidly reconfigurable rate-transparent optical networks

Optical networks which are rapidly reconfigurable and bit-rate transparent require agile clock and data regeneration (CDR) circuits that can respond quickly to different bit-rates. Real-time optical packet switching will also require burst-mode response. Present CDR techniques can be modified to rapidly synchronize to burst data if they are first tuned to the desired bit-rate. We propose and demonstrate a rapid-response bit-rate detection and selection circuit which can handle a discrete and continuous range of data rates from 10 Mb/s to 1.3 Gb/s. The circuit is suitable for programming conventional and burst mode CDR functions in regeneration, line termination, and real-time switching applications.