W-band Single-Chip Receiver MMIC and A Study on Low IF Noise Figure

Abstract

This paper presents a W-band single-chip receiver MMIC using commercial 0.15μm pHEMT technology for FMCW radar system. The receiver MMIC consists of a 4-stage low-noise amplifier, a resistive mixer, a 3-stage local oscillator (LO) buffer amplifier. In FMCW radar system using homodyne architecture IF signals are at very low frequency range which is below 1 MHz. To improve the receiver sensitivity and sensor range, the noise figure for an RF mixer is important. Any noise introduced by the RF mixer will degrade the performance of the whole receiver. This work compares the low IF NF (Noise Figure) of two types of RF mixer which are W-band resistive mixer and W-band balanced diode mixer. Mostly in low frequency, Low IF Noise Figure of RF mixer is determined by the 1/f noise of device. Therefore low IF NF (Noise Figure) measurement using spectrum analyzer and 1/f noise measurement are performed. In this study, as a result of both measurements, under the same conversion gain the noise figure of the resistive mixer is better than that of diode mixer and difference between resistive mixer and diode mixer is originated from the 1/f noise of each devices.