Two-tone measurement technique for optoelectronic trans-impedance amplifier characterisation.

ILow distortion (in addition to high sensitivity and high gain) is becoming an important requirement for the Trans-Impedance Amplifier (TIA) within the optical communications receive chain. Electronic dispersion compensation can be used to extend the use of legacy multimode fibre at 10 Gb/s. Existing measurement techniques do not partition distortion components between the source and receiver. This paper outlines a measurement technique that was applied to a high gain TIA with Automatic Gain Control to accurately determine the distortion over the entire input dynamic range. The technique can be operated over the full frequency range of the TIA and is tolerant of source harmonic distortion.