An Iterative Electro-Thermal Model for an Active Antenna Element and its Application to Arrays

Paper in proceeding, 2025

A novel electro-thermal model at the unit-cell level for active phased arrays is proposed to establish a link between the power amplifier (PA) output signal and its junction temperature. The iterative model is developed in four stages: (i) calculation of the PA output, (ii) computation of the dissipated power of the PA, (iii) thermal simulation for temperature assessment, and (iv) update on the PA output with the new temperature. These steps are repeated until the PA temperature is convergent. The use of the model is demonstrated with an amplitude-tapered 16-element array of single-stage class-A amplifier and patch antenna unit-cells at 2.14 GHz. It is observed that the inclusion of the temperature effects in the array pattern causes around a 2 dB drop in the radiated power, while the peak side lobe level (SLL) increases by up to 7.75 dB for 40 dB Taylor tapering.