| 摘要 |
A method of linearising a non-linear opto-electronic apparatus that includes an opto-electronic Mach-Zehnder modulator that receives an incoming electrical signal for modulating a light signal passing through the modulator, where the transfer characteristic of the modulator is sinusoidal, and including means for detecting the modulating light signal and for digitizing the detected signal, wherein the method comprises the following steps: injecting one or more calibration tones as an input electrical signal and obtaining a digitized form of the output signal obtaining the spectrum of said digitized form and measuring the spectral values at the frequencies of the input tone or tones and at the frequencies of spectral lines arising from the non-linearity; providing, from said spectral values, an inverse form of the non-linearity; and performing linearization on subsequent output signals for arbitrary input signals by applying said inverse form of the non-linearity to the output signal.
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