A new method to obtain total power receiver equivalent noise temperature

A method to obtain more accurate noise temperature of a radiometer at room temperature using commercial noise sources is presented. A low noise amplifier used in a radiometer system has an equivalent noise temperature which adds the contributions of its equivalent noise temperature at each frequency over its operating frequency range. The Y-factor has been improved and generalised to take into account the dependence with frequency of the noise source and the transfer function of a receiver. This dependence is especially relevant for broadband radiometer systems. A commercial simulator is used to validate the method and a Ka-band total power radiometer is characterized following the proposed method.