Distortion prediction and analysis for modern lightwave catv systems and microcellular mobile radio networks

Abstract EN

In this paper, measurement and analytical results of distortion beat characterization are discussed.

Linearity performance of semiconductor lasers working with CATV AM¬VSB optical links are studied using a nonlinear laser model based on laser rate equations constructed using a symbolically defined device (SDD) in Agilent¬ADS.

The bias and frequency dependence of second and third order two and three tone intermodulation distortions are predicted and compared to the equivalent measurements using distributed feedback (DFB) lasers (InGaAsP¬InP Fujitsu FLD3F7CZ) to verify the model.

The results confirmed that the predicted performance using the proposed model is in good agreement with the measured performance.

Composite second order (CSO) and composite triple beat (CTB) distortions in CATV systems are predicted using a standard NTSC frequency plan with 77 analog video modulated carriers in the frequency band from 48 MHz to 540 MHz, spaced 6 MHz apart.