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This paper presents analytical models of SiGe HBT and low-noise amplifier (LNA) noise parameters accounting for high-frequency noise correlation. The models are verified using measurement data and circuit simulation. The impact of noise correlation is shown to be a strong function of base resistance rb and emitter resistance re, which act as both noise sources and resistance. Correlation and roles of rb and re as resistance have opposite effects on minimum noise figure NFmin, which explains why a widely used NFmin model that neglects correlation and roles of rb and re as resistance sometimes agreed with measurements. The agreement, however, does not hold for noise matching source resistance Ropt, an important parameter for LNAs. With correlation, noise matching condition is better met for impedance matched LNAs.