Measured pulse-stuffing jitter in asynchronous ds-1/sonet multiplexing with and without stuff-threshold modulation circuit

The letter reports the measurement of pulse-stuffing jitter levels up to 0.2UIrms when an asynchronous DS-1 is transported in the current draft-standard SONET format. We then describe a new circuit technique for jitter suppression which does not require format alteration, and report measured jitter reductions of ll¿16dB for asynchronous DS-1/ SONET multiplexing. We offer an explanation as to why jitter is not significantly reduced by recent SONET format rearrangements, and show illustrative jitter spectra demonstrating the operative principle of our jitter reduction circuit.