The distribution of multiple AM VSB CATV channels over Hybrid Fiber/Coax (HFC) networks is degraded by intermodulation products generated in the optical and electronic components of the network. Techniques for analyzing this phenomena have been well documented in industry literature. These techniques use multiple CW carriers to model AM VSB CATV channels. Unfortunately, these techniques do not directly prdict performance when cetain of those analong video carriers are replaced with carriers modulated with digital services using modulation techniques such as QAM. A technique is presented that accurately relats conventional system characterizations using CW carriers to performance when the system is loaded with a mixture of analog and digital serfvices. Empirical data is included to wverify the accuracy of this technique. Corrections are proposed in order to account for the effect of uncorrelated video modulation on the AM VSB carriers.
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