High linearity active GaN-HEMT down-converter MMIC for E-band radar applications

A down-converter MMIC in 100 nm gate length AlGaN/GaN HEMT technology achieves an input-related 1-dB compression point of 13 dBm at a center frequency of 77 GHz, providing high linearity for radar applications. The single-ended fundamental mixer without pre- or post-amplification shows 8 dB conversion loss when driven with 13dBm of LO power within an RF frequency range exceeding 75 to 81 GHz. The high linearity is achieved by operating the GaN transistor as active transconductance mixer, allowing for a high voltage swing of the RF signal even when using a relatively small transistor size as required by the high operating frequency.