A 22‐37 GHz low noise amplifier with 2.8 dB mean noise figure and +22.9 dBm output 3rd‐order intercept point for 5th generation applications

Abstract

This paper presents a wideband 22‐37 GHz low noise amplifier (LNA) realized in a 0.25 μm SiGe BiCMOS technology. The design incorporates additional noise matching between the cascode transistors to minimize the noise figure (NF) degradation. The second stage incorporates an active balun architecture with a tail inductor to improve the common‐mode rejection ratio (CMRR). To extend the bandwidth, a capacitive feed forward path is added at the second stage. The LNA presents a minimum in‐band NF of 2.3 dB from 22‐37 GHz. The achieved 3 dB‐gain bandwidth is larger than 15 GHz, with a peak gain of 20.8 dB at 28 GHz. The output 3rd‐order intercept point (OIP3) is +22.9 dBm for a total power consumption of 94 mW. The area of the core circuit is 0.35 × 0.47 mm2. To the author's knowledge, the LNA shows the best overall performance compared to the existing silicon‐based LNAs.

Experimental insight into the third‐order intercepts and nonlinear distortion of GaN HEMTs

“…This intercept point may be a simply numerical concept; does not compare to an essentially happening physical power level to describe and accurately measure the intermodulation distortion (IMD) and demonstrate how a receiver works within close proximity to strong adjacent signals. Nearly continuously, the intercept point is beyond the straight operation of the device 11‐15 . This is a hypothetical point that extrapolated from the linear (eg, fundamental, P fund .)…”

“…Nearly continuously, the intercept point is beyond the straight operation of the device. [11][12][13][14][15] This is a hypothetical point that extrapolated from the linear (eg, fundamental, P fund .) and third-order (P IMD3 ) intermodulation components by extrapolating an imaginary straight line.…”