Antenna processes and temperature of radiation

Let us call the reemission of solar energy during an antenna process retranslation, if the temperature of the radiation remains constant, and transformation, if the temperature of the radiation changes. The retranslation of radiation by a black body is, by definition, a reversible process. Transformation can take place both in a reversible and irreversible way. Therefore, the efficiency of the work performed by a solar cell can be improved by increasing the fraction of retranslating and transforming reversible antenna processes as well as working equilibrium states in an absorber.