High-Speed Optical and Electrical Measurements
The Optoelectronics Division provides three different services related to optical and electrical signal measurements:
- Reference Receiver (Optical Oscilloscope) Vector Frequency Response - Oscilloscopes used for testing optical eye-patterns are specified in standards (such as SONET, SDH, Gigabit Ethernet, and Fibre Channel) to follow a 4 th-order Bessel-Thompson impulse response. Oscilloscopes used for testing other optical waveforms should have a high bandwidth and be free from aberrations. This service uses an optical impulse, along with corrections for jitter and timebase distortion, to calibrate the impulse response of oscilloscopes with a fiber-optic input.
- Calibrated electrical impulse source - A calibrated electrical pulse source that customers can use to characterize their high-speed electrical components and test equipment is maintained by NIST and is available for customer use. This electrical pulse source, a photodiode, generates an electrical impulse of roughly 5 ps duration and about 8.67 MHz repetition rate. The spectrum this impulse source delivers to an ideal 50 Ohm laod has been characterized in 0.2 GHz increments from 0.2 GHz to 110 GHz at the 1.00 mm (male) coaxial output connector. The spectrum has been characterized with an expanded uncertainty (95% confidence interval) in the response magnitude typically less than 0.4 dB and expanded uncertainty in the response phase that is typically less than 3 degrees.
- Sampling oscilloscope vector frequency response - The calibrated electrical impulse source described above is used to calibrate the vector frequency response of a customer's high-speed sampling oscilloscope. This service includes corrections for impedance mismatch and oscilloscope timebase errors (timebase distortion, jitter, and drift). Results are reported, for an oscilloscope with a 1.00 mm (female) input connector, in 0.2 GHz increments from 0.2 GHz to 110 GHz.
Please contact Paul Hale or visit our High-Speed Measurements Project Web site for additional technical information.
|Reference Receiver (Optical Oscilloscope) Vector Frequency
||800 and 1550 nm
||100 fs impules source
|Sampling Oscilloscope Vector Frequency Response
|Calibrated Pulse Source
NIST Tech. Note 1535