A linearized polar transmitter for wireless applications

This paper reports on a new design method to overcome the nonlinear distortion associated to polar transmitters. The proposed methodology complements the modulation of drain bias, v_DD(t), of conventional envelope elimination and restoration power amplifiers with a proper variation of the input drive level, v_g(t). Allowing v_g(t) to vanish when v_DD(t) goes to zero, it obviates the inherent nonlinear distortion caused by the amplifier carrier feed-through. In addition, and beyond guaranteeing linear operation, such a design methodology is also beneficial for power added efficiency as it prevents the dissipation of instantaneous input power for a desired null instantaneous output power.