A Ku-Band CMOS Balanced Driver Amplifier With Transformer-Based Notch Filter for SATCOM Phased Arrays

Abstract

This brief presents a Ku-band balanced driver amplifier (BDA) for SATCOM phased arrays. To facilitate a flexible and low-loss coupler design, the non-correlation between the coupling coefficient and the output power of BDA is illustrated. The passive transformer-based notch filter is co-optimized with the inter-stage matching network. The sideband rejection is improved while maintaining high gain and linearity. The second harmonic trap technique is also applied to alleviate the amplitude-to-phase (AM-PM) distortion. Fabricated in 65-nm CMOS technology, the proposed BDA provides the maximal gain of 26 dB at 14 GHz with the highest sideband rejection of 26 dB. The input and output return losses are both better than -15 dB. It achieves a measured 1-dB compressed power (P1dB) of 19.5 dBm with the maximal power-added efficiency (PAEmax) of 27.8%. The small-signal gain and P1dB vary only 2 dB and 0.8 dBm from -55∘C to 85∘C, respectively.