Abstract

In an ultra high speed optical communications system, the clock signal from a data stream in NRZ format is recovered using an inexpensive, low Q filter. Resulting clock jitter is reduced with a clock divider which lowers the speed of the signal by 1/n, where n is a an integer. The divided clock signal is filtered again by a low frequency high Q filter. This invention eliminates the need for a costly high frequency high Q filter, while providing a divided down clock for data de-multiplexing. At the lower speed, an inexpensive D flip flop is used with the divided down clock for data recovery.