Lightwave multi-channel analog AM video distribution systems

Device linearity and noise requirements for multichannel amplitude-modulated subcarrier-multiplexing (AM-SCM) lightwave systems are discussed. Laser nonlinearity, most notably second-order distortion, is found to limit the maximum modulation, that can be applied to the laser. The resultant composite second- and third-order distortion can be predicted from conventional two-tone laser linearity measurements. The carrier-to-noise ratio (CNR) for the modulation depth allowed by linearity requirements is found to be limited by intensity noise and noise from the receiver preamplifier.<
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