A Broadband Analog Predistortion Linearizer Based on Tunable Diodes for Ka Band Power Amplifier

In this paper, we propose a broadband analog predistortion (APD) linearizer using two-path architecture based on tunable diodes to provide independent control of phase and gain responses for optimal distortion compensation for Ka band power amplifier (PA). The proposed APD architecture achieves superior intermodulation distortion (IMD3) and drain efficiency improvements for broadband power amplifier at millimeter-wave frequency. A class AB power amplifier cascaded with this linearizer, excited by a 5M two-tone signal, there is 11.5-22.6dB improvement in the third order of intermodulation distortion (IMD3) in the full band of 27-31GHz. The drain efficiency of amplifier improves from 3.47% to 9.89% at 1dB compression output power.