A 38-GHz Down-Converter with Low Noise Variable Gain Amplifier Having 24dB Dynamic Range in SMT Package

In the higher frequency bands of the point-to-point communication systems, it is difficult to achieve a Low Noise Variable Gain Amplifier with high dynamic range along with good linearity and low noise figure. This paper describes a solution that covers the 38GHz band in low cost SMT package in the form of a complete Down-Converter MMIC. The MMIC comprises of a Low Noise Variable Gain Amplifier (LNVGA), a LO Buffer and a Sub-Harmonic Image-Reject Mixer (SHIRM). The Down-Converter provides 12.5dB of conversion gain with 24dB of gain control, + 1dBm of Input IP3 and 3.3dB NF in the 38GHz band. This complete Down-Converter is integrated in a 2.5mm x 2.35mm chip area and realized with Avago's internal 0.17um PHEMT process. The result is the most integrated and the best combination of performances to be published or advertised.