Comments on 'Microwave Noise Modeling for InP-InGaAs HBP-InGaAs HBTs'

摘要

The above paper [1] proposes analytical expressions for the noise parameters of microwave HBTs. They are compared with experimental data and with different expressions given in [2] and [3]. A strong deviation (approximately 2 dB) between the minimum noise figure calculated from [2] and experimental data at a frequency of 2 GHz is reported for several bias conditions. This disagreement in the "low-frequency" range is very surprising, as the equations given in [1, eqs. (1)-(3)] related to the intrinsic shot noise sources and their correlation are the same as those given in [2]. Noise parameter derivation based on the model given in [2] is explained and the calculated values are compared to experimental data given in [1].