Search

This paper presents a 77-GHz automotive radar receiver in a 28-nm fully depleted silicon-on-insulator CMOS technology. It exploits a mixer-first direct-conversion architecture to trade-off noise and linearity performance. The receiver is composed of a 77-GHz downconverter, a variable-gain amplifier, and a switched-capacitor low-pass filter. It adopts an effective and robust approach for leakage suppression due to the TX to RX crosstalk, which overcomes both gain and linearity limitations. The receiver draws an overall quiescent current as low as 27 mA from a 1-V supply voltage and provides an overall gain up to 75 dB with a noise figure of 8.2 dB. Despite the low supply voltage, an excellent blocker immunity of −9.5 dBm is achieved along with an output 1-dB compression point as high as −1.5 dBV. [ABSTRACT FROM AUTHOR]

This article presents a $W$ -band power amplifier (PA) for automotive radar applications. It was designed in a 28-nm fully depleted silicon-on-insulator CMOS technology with a transition frequency of around 270 GHz and a standard back-end-of-line. The circuit adopts a pseudo-differential topology with coupling transformers, which allow both compact matching networks and layout-optimized interstage interconnections. The power stage exploits a transformer-based folded-cascode structure that is very suitable for low-voltage mm-wave power applications. The PA is able to deliver a saturated output power as high as 13.5 dBm at 77 GHz with a power-added efficiency of 14.5%, while using a power supply as low as 1 V. The linear power gain is 26.5 dB and the current consumption is 150 mA. The PA occupies a core die size of $700\,\,\mu \text{m}\,\,\times 200\,\,\mu \text{m}$. [ABSTRACT FROM AUTHOR]

An effective codesign approach for harvesting systems is described in this article, which is based on a CMOS differential-drive rectifier and an inductively coupled loop (ICL) antenna. The proposed approach acts on both the rectifier and the antenna and aims at optimizing the system performance in terms of efficiency and input sensitivity for a given load specification. Moreover, a rectifier solution is also proposed to enhance the circuit performance by properly driving the transistor bulks without additional components. An RF harvesting system operating at 868 MHz was implemented, which is made up of an ICL antenna on FR-4 substrate and a rectifier fabricated in the 0.13- $\mu \text{m}$ CMOS technology. Measurements in the anechoic chamber show an overall efficiency performance of 34% with an RF input power as low as −21.5 dBm while considering 2.4 V and 1 $\mu \text{A}$ as load specifications. [ABSTRACT FROM AUTHOR]

This paper presents a Colpitts-based voltage-controlled oscillator (VCO) for W-band radar applications. In the proposed circuit, the oscillation signal is directly drawn from the switching transistor bases by means of the primary winding of a transformer tank, while the secondary winding drives the output buffer. This solution improves both tuning range and oscillation swing with respect to traditional millimeter-wave VCO topologies without increasing power supply. The oscillator is implemented in a 0.13-\mu\ m SiGe BiCMOS technology, along with high-frequency dividers to enable low-frequency testing. The VCO exhibits a phase noise of -\99.3 dBc/Hz at 1-MHz offset from an oscillation frequency of 76 GHz and a tuning range of 4.9% with a consumption of 65 mW at 2.5-V power supply. The VCO is also used to drive a two-stage power amplifier in a fully integrated W-band transmitter that is able to deliver an overall output power as high as 15 dBm at 76 GHz. [ABSTRACT FROM AUTHOR]

This paper presents a pseudodifferential power amplifier for 77-GHz automotive radar. The circuit is fabricated in a SiGe HBT BiCMOS technology featuring bipolar transistors with fT/f\max of 230/280 GHz. The amplifier adopts a transformer-coupling current-reuse approach to improve both gain and efficiency. An interstacked transformer is also profitably adopted to reduce output losses due to the differential-to-single-ended conversion. The amplifier exhibits a saturated power, a peak power-added efficiency, and a gain of 14.5 dBm, 9%, and 25 dB, respectively, thus achieving a first-rate figure-of-merit as high as 4755. [ABSTRACT FROM PUBLISHER]

This paper presents a 15-dBm power amplifier for 77-GHz automotive radar applications, which is fabricated in a 0.13-\mu\ m SiGe:C BiCMOS process featuring bipolar transistors with f T / f\max of 230/280 GHz. The circuit consists of a two-stage pseudodifferential cascode with fully integrated input/output matching networks. State-of-art performance is achieved with the proposed design algorithm and layout optimization. The amplifier demonstrates a figure-of-merit of 2500 achieving a 22.5-dB power gain and a power-added efficiency of 7.5% at 77 GHz, while drawing 130 mA from a 2.5-V voltage supply. [ABSTRACT FROM AUTHOR]

The analysis and modeling of monolithic stacked transformers fabricated in a high-speed silicon bipolar technology is addressed. On-wafer experimental measurements are employed to investigate the effect of layout scaling on transformer performance parameters (i.e., self-resonance frequency, magnetic coupling coefficient, and insertion loss). Based on this analysis, a wideband lumped model is developed, whose parameters are related to layout and technological data through closed-form expressions. Model accuracy is demonstrated by comparing simulated and measured S-parameters, coil inductance, magnetic coupling coefficient, and maximum available gain of several transformers with scaled layout geometry. The self-resonance frequency is also employed as a figure-of-merit to demonstrate model accuracy at very high frequency. [ABSTRACT FROM AUTHOR]