86107A Precision Timebase Reference Module The 86107A precision time-base reference module is a sampling oscilloscope accessory that addresses the challenges that design engineers face in measuring jitter in optical networks with data transmission rates at 40 Gb/s and higher. It uses a time-phase clock reference architecture, which enables subpicosecond jitter measurements. Using this approach, precise accounting for the time elapsed prior to the oscilloscope sampling event is not required. Rather, the phase of the signal under test relative to the clock reference signal is determined.Produced by Agilent Technologies Inc.'s Lightwave Div. in Santa Rosa, Calif., the device requires the use of a customer-supplied reference clock that is synchronous to the data being measured. Because the application target for the module is telecommunications, the clock frequency must be in the 9.0- to 12.6-, 18.0- to 25.0- or 39.0- to 45.0-GHz ranges. This allows the standard 10-, 20- or 40-Gb data rates, along with most forward error correction encoding schemes.The 86107A can be used for electrical or optical device characterization, from a 70-GHz electrical to an 800-GHz optical bandwidth capability. Its fine temporal resolution and time-base linearity enable it to differentiate various types of jitter within a modulated waveform. Whether the data modulation format is return-to-zero or nonreturn-to-zero, data-dependent and random jitter are usually averaged together.