The invention relates to a method of designing a heater (10) comprising an electric element (12) heated by radiation, said electrical heating element comprising: a front panel (14) formed of an emissive material (M) ; and an electric resistance (22) in thermal contact with a rear face (26) of the facade; the heater further comprising a power supply (20) to form periodic electrical resistance. According to the process design, a pulsation (ω) of the power supply of the electrical resistance is determined; and
- a thickness (E) between the front face (24) and the rear face (26) of the facade is chosen greater than or equal to a value (Emin) defined by the formula (1): $$\mathrm{Emin}=\mathrm{B}\sqrt{\frac{\mathrm{\lambda }}{\mathrm{\rho }\mathrm{.}{\mathrm{C}}_{\mathrm{p}}\mathrm{.}\mathrm{\omega }}}$$ B being a constant, and C _p, ρ and λ being the thermal capacity, respectively, the thermal conduction and the density of the emissive material of the facade.