SiGe Low Noise Amplifier Research Articles

Figures‐of‐merit genetic extraction for InGaAs lasers, SiGe low‐noise amplifiers, and ZnSe/Ge/GaAs HBTs

AbstractIn this paper, we have successfully developed an intellectual parameter‐extraction methodology on the basis of a genetic algorithm (GA), involving the efficient search‐space separation and local‐minima‐convergence prevention schemes. Via an evolutionary simulation tool complemented with appropriate analytic equations, the enhanced approach has been applied to determine the significant figures‐of‐merit (FoMs), including internal quantum efficiency (ηi) as well as transparency current density (Jtr) of semiconductor lasers, minimum noise figure (NFmin) as well as associated available gain (GA,assoc) of low‐noise amplifiers (LNAs), and DC as well as AC characteristics of heterojunction bipolar transistors (HBTs). For the first time, demonstrated FoM‐extraction results, which coincide well with the actually measured data, for state‐of‐the‐art InGaAs quantum‐well lasers, advanced SiGe LNAs, and abrupt ZnSe/Ge/GaAs HBTs are simultaneously presented to validate this multi‐parameter analysis and robust optimization. Copyright © 2011 John Wiley & Sons, Ltd.

Mixed-Mode Extraction of Figures of Merit for InGaAs Quantum-Well Lasers and SiGe Low-Noise Amplifiers

We propose a new parameter-extraction approach based on a mixed-mode genetic algorithm (GA), including the efficient search-space separation and local-minima-convergence prevention process. The technique, substantially extended from our previous work, allows the designed figures-of-merit, such as internal quantum efficiency (ηi) as well as transparency current density (Jtr) of lasers and minimum noise figure (NFmin) as well as associated available gain (GA, assoc) of low-noise amplifiers (LNAs), extracted by an analytical equation-based methodology combined with an evolutionary numerical tool. Extraction results, which agree well with actually measured data, for both state-of-the-art InGaAs quantum-well lasers and advanced SiGe LNAs are presented for the first time to demonstrate this multi-parameter analysis and high-accuracy optimization.

R&D at Nançay for radio astronomy detectors and systems

Nançay radio astronomy station teams are involved in several aspects of the Research and Development (R&D) for radio astronomy detectors and systems: i) Microelectronics: Low Noise Amplifiers (LNA), receiver on chip and system in package. The long-term goal is to provide sub-systems for the future Square Kilometer Array and its Pathfinders. A beamformer chip has been integrated in the FP6 SKADS dense aperture array technology demonstrator EMBRACE. Wide band SiGe LNAs are developed, beamformers with in-chip control are studied and more complex integrated receivers are designed for the european Aperture Array Verification Programme demonstrator. ii) Digital signal processing: EMBRACE beamforming has been implemented in the digital backend and RFI-mitigation oriented signal processing has been designed for realtime systems, including work for FP6 SKADS and FP7 PrepSKA. iii) A study of Phased Array Feeds has started in 2008, in order to study the radio electric properties of PAFs at the focus of large F/D telescopes, such as the Nançay Radio Telescope, as well as to test PAF systems in collaboration with the SPP/IRFU and LAL/IN2P3 laboratories.

Single-Ended and Differential Ka-Band BiCMOS Phased Array Front-Ends

Single-ended and differential phased array front-ends are developed for Ka-band applications using a 0.12 mum SiGe BiCMOS process. The phase shifters are based on CMOS switched delay networks and have 22.5deg phase resolution and <4deg rms phase error at 35 GHz, and can handle +10 dBm of RF power (P <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1dB</sub> ) with a 3rd order intermodulation intercept point (IIP3) of +21 dBm. For the single-ended design, a SiGe low noise amplifier is placed before the CMOS phase shifter, and the LNA/phase shifter results in 11 plusmn 1.5 dB gain and <3.4 dB of noise figure (NF), for a total power consumption of only 11 mW. For the differential front-end, a variable gain LNA is also developed and shows 9-20 dB gain and <1deg rms phase imbalance between the eight different gain states. The differential variable gain LNA/phase shifter consumes 33 mW, and results in 10 + 1.3 dB gain and 3.8 dB of NF. The gain variation is reduced to 9.1 plusmn 0.45 dB with the variable gain function applied. The single-ended and differential front-ends occupy a small chip area, with a size of 350 times 800 mum <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> and 350 times 950 mum2, respectively, excluding pads. These chips are competitive with GaAs and InP designs, and are building blocks for low-cost millimeter-wave phased array front-ends based on silicon technology.

SiGe HBT X-Band LNAs for Ultra-Low-Noise Cryogenic Receivers

We report results on the cryogenic operation of two different monolithic X-band silicon-germanium (SiGe) heterojunction bipolar transistor low noise amplifiers (LNAs) implemented in a commercially-available 130 nm SiGe BiCMOS platform. These SiGe LNAs exhibit a dramatic reduction in noise temperature with cooling, yielding of less than 21 K (0.3 dB noise figure) across X-band at a 15 K operating temperature. To the authors' knowledge, these SiGe LNAs exhibit the lowest broadband noise of any Si-based LNA reported to date.

Reconfigurable SiGe Low-Noise Amplifiers With Variable Miller Capacitance

A new input matching method making use of shunt-shunt feedback capacitance is introduced. Based on the new input matching method, reconfigurable SiGe low-noise amplifiers (LNAs) by varying shunt-shunt feedback capacitance are proposed. Two approaches are used to vary the shunt-shunt feedback capacitance. One approach is to switch between two different bias currents while the other is to use a series combination of a switch and a capacitor. Miniaturized fully monolithic reconfigurable SiGe LNAs without emitter degenerative inductors were realized by the above two approaches. The reconfigurable SiGe LNA achieved by switching bias currents only occupies a very small area of 355 mumtimes155 mum, excluding measurement pads. This LNA achieves an input return losses (S11) of -27.6 dB, a voltage gain (A v) of 19.8 dB, and a noise figure (NF) of 3.18 dB for 2.4-GHz band when biased at a current of 3.8 mA and can be reconfigured to obtain Av=20.4/20.3 dB, S11=-47.1/-24.6 dB and NF=3.42/3.21 dB for 5.2/5.7-GHz band when bias current is switched to 3 mA. In addition, a 2.4/4.9/5.2/5.7-GHz reconfigurable SiGe LNAs for WLAN applications, whose variable shunt-shunt feedback capacitance is controlled by a switch and a capacitor, was also realized

Theoretical Analysis of a Low Dispersion SiGe LNA for Ultra-Wideband Applications

We demonstrate a low dc power consumption SiGe heterojunction bipolar transistor (HBT) low noise amplifier (LNA) for ultra-wideband (UWB) applications covering the 0.5GHz to 10GHz band. Using theoretical analysis, the dominant design factor for low group delay variation is identified and applied to UWB LNA design. The implemented SiGe LNA achieves a gain of 13dB, a minimum noise figure of 3.3dB, and an IIP3 of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$-$</tex> 7.5dBm between 0.5GHz and 10GHz, while consuming a dc power of only 9.6mW. This SiGe UWB LNA exhibits less than 22ps of uniform group delay variation over the entire band. To the best of the authors' knowledge, this is the first attempt to analyze the effects of group delay variation on the operation of wideband LNAs.

The analysis of UWB SiGe HBT LNA for its noise, linearity, and minimum group delay variation

The design of ultra-wideband (UWB) low-noise amplifiers (LNAs) require additional circuit design principles, which differ from those used in conventional LNAs. The design of a low-dc-power-consumption SiGe HBT LNA covering the 2-10-GHz range is demonstrated for UWB applications. Important design factors that must be carefully considered for UWB applications are analyzed, which include power dissipation, operating bandwidth, noise figure, group delay variation, and linearity. The dominant factor for low group delay variation in UWB LNAs is identified through the theoretical analysis. The linearity behavior over the wide bandwidth is analyzed and explained using the Volterra series. Second-harmonic cancellation is determined to be the dominant degradation factor for linearity. The implemented SiGe LNA achieves a gain of 13 dB, a minimum noise figure of 3.3 dB, and an input third-order intercept point of -7.5 dBm between 2-10 GHz while consuming a dc power of only 9.6 mW. This SiGe UWB LNA exhibits less than 22 ps of uniform group delay variation over the entire band.

Proton radiation response of monolithic Millimeter-wave transceiver building blocks implemented in 200 GHz SiGe technology

This work presents the first experimental results on the effects of 63.3 MeV proton irradiation on 60 GHz monolithic point-to-point broadband space data link transceiver building blocks implemented in a 200 GHz SiGe heterojunction bipolar transistor (HBT) technology. A SiGe low-noise amplifier and a SiGe voltage-controlled oscillator were each irradiated to proton fluences of 5.0/spl times/10/sup 13/ p/cm/sup 2/. The device and circuit level performance degradation associated with these extreme proton fluences is found to be minimal, suggesting that such SiGe HBT transceivers should be robust from a proton tolerance perspective for space applications, without intentional hardening at either the device or circuit level.

The Effect of Geometry on the Noise Characterization of SiGe HBTs and Optimized Device Sizes for the Design of Low-Noise Amplifiers

The impacts of various layout configuration and device dimensions on device performance are examined. The geometrical scaling issues including emitter length and emitter stripe-number scaling are used to shift simultaneously the optimum noise and optimum source impedance to a point that is close to 50 /spl Omega/. Via this method, not only is the optimal transistor size for low-noise applications obtained, but the matching network is simplified to reduce the losses of passive networks and the chip area. Based on experimental results, optimum SiGe HBTs and bias suitable for low-noise amplifiers (LNAs) are determined. Via the comparison of the state-of-the-art SiGe LNAs, it is confirmed that this method is effective to obtain better performances. Using the same method, the optimum device size at any bias and any frequency for low-noise applications can also be achieved.