Low Noise Figure Research Articles

Monolithically Integrated Directly Pumped Time-Varying Transmission Lines

A novel directly pumped time-varying transmission line (DP-TVTL) is proposed here and implemented on gallium arsenide (GaAs) microwave monolithic integrated circuit (MMIC). Comparing to existing TVTL architectures where the pump wave is launched through the transmission line, the pump wave in the DP-TVTL is directly fed to the different parts of the transmission line through a parallel power division network. The impedance of TVTL is modulated by the pump through diode bridges that isolate the signal path from the pump path. The power division network creates a phase delay emulating that of a traveling-wave delay line yet without launching the physical pump wave on the TVTL. This avoids the loss of the pump energy propagating through the transmission line. It also adds more freedom in the design of the bandgap properties of TVTL and simplifies the combination/separation circuitry for waves at different frequencies in and out of the TVTL. The resulting MMIC TVTL offers exceptional, broadband conversion gain performance of up to 4.2 dB, a low noise figure of 3 dB, and input referred P1dB of 12 dBm when used as a parametric mixer. It may be used in an RF front end as a mixer first receiver or an RF correlator.

A Sub-GHz Low-Power Receiver Employing Resistive-Feedback-Tuned LNA With 2.1-dB NF and 106-dB Gain Tuning Range

This letter presents a configurable sub-GHz low-power receiver achieving a low noise figure (NF) and a large gain tuning range. An inverter-based low-noise amplifier (LNA) with a resistive-feedback-tuning technique is realized to achieve low power and optimize NF while tuning the gain level. Implemented in 130-nm CMOS technology, this receiver occupies an active area of 2.3 mm2. It achieves a low power of 3.63 mW over a large gain tuning range of 106 dB in 6 dB steps. It also achieves a low NF of 2.1 dB and an image rejection ratio (IRR) of over 37.1 dB.

A Compact 1.0–12.5-GHz LNA MMIC With 1.5-dB NF Based on Multiple Resistive Feedback in 0.15-μm GaAs pHEMT Technology

In this paper, a 2-stage compact wideband low-noise amplifier (LNA) monolithic microwave integrated circuit (MMIC) with multiple resistive feedback (MRFB) is presented. From the DC point of view, the proposed MRFB functions as a self-biasing structure to bias transistors in the optimal condition, improving the noise figure (NF) and linearity. Meanwhile, by employing MRFB with source degeneration and input inductor, the proposed LNA achieves wideband flat gain at the AC side. In comparison with traditional topologies, a wide bandwidth of more than 11.5 GHz with low noise figure of less than 2.5 dB can be achieved. To verify the proposed LNA structure, a chip prototype is fabricated in a 0.15- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> GaAs E-mode pHEMT process with a compact die size of only 0.75 mm2 including all the testing pads. From the measurement results, the proposed LNA circuit features a 1.0 to 12.5 GHz 3-dB working bandwidth (172% fractional bandwidth), 23.6 peak gain, 1.51 dB minimum NF, 66.7± 15 ps group delay, and 24.3/12.6 dBm best OIP3/OP1dB, respectively. The total DC power is around 87.5 mW from a single 2.5-V power supply.

On the resilience of dual-waveguide parametric amplifiers to pump power and phase fluctuations

Parametric amplifiers based on coupled-core fibers and coupled integrated waveguides are promising devices for delivering broadband and flat gain spectrum with low noise figure in vital technological applications such as optical communications. To address potential practical issues that may arise in the experimental demonstration, in the present work, we derive analytical expressions for the impact of relative input pump phase and power fluctuations between two waveguides on pump waves stability. We, furthermore, evaluate, through numerical simulations, how the pump power oscillations between the two waveguides affect the amplifier spectrum, identifying optimal regimes of operation for coupled-core fibers and also for coupled integrated waveguides. Our findings hint at the resilience of these parametric amplifiers' architectures and at their possible practical implementation in realistic labs and real-world scenarios.

Cladding pumped bismuth-doped fiber amplifiers operating in O-, E-, and S-telecom bands.

Bismuth-doped fibers (BDFs) are considered nowadays as an essential part of the development of novel optical amplifiers, which can provide a significant upgrade to existing fiber optic telecommunication systems, securing multiband data transmission. In this paper, a series of BDF amplifiers (BDFAs) for O-, E-, and S-telecom bands based on a cladding pumping scheme using low-cost multimode semiconductor laser diodes at a wavelength of 0.7-0.8 µm were demonstrated for, it is understood, the first time. The developed BDFAs are characterized by a high peak gain of >25-30 dB in the corresponding telecom bands and a relatively low noise figure of 5-6 dB. Comparative analysis shows that most of the parameters of cladding pumped BDFAs are close to those of the best core pumped ones. This research opens up new opportunities for utilizing Bi-doped fibers as a key element of cost-effective and ready-to-work BDFAs for various practical applications.

A 12.4–32 GHz CMOS Down-Conversion Mixer for 28 GHz 5G New Radio (NR)

We report a low voltage (VDD) and power (PDC) 12.4–32 GHz CMOS down-conversion mixer with high conversion gain (CG) for 28 GHz 5G communications. A quarter-wavelength (λ/4) transmission line (TL) and a coupling capacitor (Cc), named the λ/4-TL-C-based coupler, is proposed. This is the way to attain low-VDD, independent RF transconductance (gm)-stage bias, harmonic suppression, and near perfect coupling from the RF gm stage to the LO switch transistors. The body-self-forward-bias (BSFB) technique, i.e., connection of the gm-stage transistors’ body to drain via a large body resistance, is used for threshold voltage (Vth) and VDD reduction and substrate leakage suppression. CG and noise figure (NF) enhancement at the same or even a lower PDC is achieved because lower VDD and higher gm (due to larger bias current) are used. To facilitate the RF measurement, a compact Wilkinson-power-divider-based balun with small-phase deviation and amplitude imbalance is included at RF and LO inputs. The mixer consumes 6.5 mW and achieves a CG of 14.4 ± 1.5 dB for 12.4–32 GHz (i.e., 3 dB bandwidth (f3dB) of 19.6 GHz), a lowest noise figure (NFmin) of 7 dB, and figure-of-merit (FOM) of 0.023, which is one of the best results ever reported for millimeter-wave (mm-wave) down-conversion mixers with an f3dB larger than 10 GHz and PDC lower than 10 mW.

Highly Integrated Wideband Transmit/Receive Module for X-Band SAR Applications

The roadmaps of satellite-based synthetic aperture radar (SAR) systems show a trend that requires a continuous improvement of the active antenna in terms of operating bandwidth, scanning angle capability, and swath width, thus leading to the demand for increased RF power and better power efficiency of the RF transmitter. Moreover, compact size and light weight are relevant objectives for making the overall SAR instrument appealing for future applications. The transmit/receive module (TRM) shown in this paper was developed while combining all these requirements in a cost-effective approach. A careful design of all relevant RF interconnects and passive devices was performed to ensure the largest output power from the last high-power amplifier of the transmitting chain, the lowest noise figure at the input of the receiving chain, and the calibration capability for appropriately tuning the TX and RX signal. The TRM was manufactured and experimentally tested to verify its performances. The measurement results show the superior performances of the proposed compact high-power large-bandwidth TRM. The achieved target objectives make the design of the proposed TRM readily applicable for the development of a compact, high-power, and highly integrated AESAs to be used for next-generation satellite constellations for Earth observation.

Non-reciprocal acoustoelectric microwave amplifiers with net gain and low noise in continuous operation

Piezoelectric acoustic devices that are integrated with semiconductors can leverage the acoustoelectric effect, allowing functionalities such as gain and isolation to be achieved in the acoustic domain. This could lead to performance improvements and miniaturization of radio-frequency electronic systems. However, acoustoelectric amplifiers that offer a large acoustic gain with low power consumption and noise figure at microwave frequencies in continuous operation have not yet been developed. Here we report non-reciprocal acoustoelectric amplifiers that are based on a three-layer heterostructure consisting of an indium gallium arsenide (In0.53Ga0.47As) semiconducting film, a lithium niobate (LiNbO3) piezoelectric film, and a silicon substrate. The heterostructure can continuously generate 28.0 dB of acoustic gain (4.0 dB net radio-frequency gain) for 1 GHz phonons with an acoustic noise figure of 2.8 dB, while dissipating 40.5 mW of d.c. power. We also create a device with an acoustic gain of 37.0 dB (11.3 dB net gain) at 1 GHz with 19.6 mW of d.c. power dissipation and a non-reciprocal transmission of over 55 dB.

Ultrahigh dynamic range and low noise figure programmable integrated microwave photonic filter

Microwave photonics has adopted a number of important concepts and technologies over the recent pasts, including photonic integration, versatile programmability, and techniques for enhancing key radio frequency performance metrics such as the noise figure and the dynamic range. However, to date, these aspects have not been achieved simultaneously in a single circuit. Here, we report a multi-functional photonic integrated circuit that enables programmable filtering functions with record-high performance. We demonstrate reconfigurable filter functions with record-low noise figure and a RF notch filter with ultra-high dynamic range. We achieve this unique feature using versatile complex spectrum tailoring enabled by an all integrated modulation transformer and a double injection ring resonator as a multi-function optical filtering component. Our work breaks the conventional and fragmented approach of integration, functionality and performance that currently prevents the adoption of integrated MWP systems in real applications.

A 90‐ to 115‐GHz superheterodyne receiver front‐end for W‐band imaging system in 28‐nm complementary metal‐oxide‐semiconductor

SummaryIn this paper, a broadband superheterodyne receiver (RX) front‐end for millimeter‐wave (mm‐Wave) imaging radar is presented. Realized in 28‐nm CMOS technology, the proposed RX incorporates a wideband low‐noise amplifier (LNA), double‐balanced passive mixers for the dual down‐conversion, a differential power divider, a differential intermediate frequency filters, a current‐mode‐logic divider‐by‐2, and a local oscillator buffers. Wideband technique and layout optimization are taken into consideration in the RX. A four‐stage LNA is devised to realize the high gain and low noise figure (NF) with a common‐gate input stage and three pseudodifferential common‐source stages. Optimized transistor layout and capacitor neutralization technique are developed to improve gain and noise performance. Transformer‐based matching networks with the peak‐staggered technique are adopted in the LNA to achieve a flatter gain response with a wider bandwidth (BW). The passive double‐balanced mixers are implemented with a highly symmetrical layout for broadband down‐conversion. Simulation results show that the mm‐Wave RX front‐end exhibits a BW ranging from 90 to 115 GHz. The simulated NF of our RX is 4.7 dB at 86 GHz. With a supply voltage of 1 V, the presented RX consumes 88.2‐mW power and occupies a chip size of 1.6 × 0.5 mm2 including all the testing pads. The proposed RX is suitable for W‐band imaging systems.

Design of Common Gate Current-Reuse Noise Cancellation UWB Low Noise Amplifier in 90nm CMOS

In this paper, an ultra-wide band (UWB) low noise amplifier (LNA) is implemented by using 90nm RF CMOS technology. The designed LNA achieves high flat band gain (S21) and low noise figure (NF) in the frequency of interest. The proposed LNA operates in the frequency range of 3GHz to 8GHz. In this work, wide band matching is achieved by designing common gate configuration at the input stage. The current reuse and noise cancellation techniques are introduced to improve flat band gain and minimize both noise figure and power consumption. The noise figure is improved by cancelling dominant noise sources with additional hardware. The proposed LNA attains flat band gain of 26.5dB and input matching less than -12dB for entire UWB band. This work achieves noise figure of 2.1dB to 2.59dB in frequency band of interest. Additionally, power consumption of the circuit is 20mW at 1.8V supply voltage.

Advances in Ku-Band GaN Single Chip Front End for Space SARs: From System Specifications to Technology Selection

In this paper, a single-chip front-end (SCFE) operating in Ku-band (12–17 GHz) is presented. It is designed exploiting a GaN on SiC technology featured by 150 nm gate length provided by UMS foundry. This MMIC integrates high power and low noise amplification functions enabled by a single-pole double-throw (SPDT) switch, occupying a total area of 20 mm2. The transmitting chain (Tx) presents a 39 dBm output power, a power added efficiency (PAE) higher than 30% and a 22 dB power gain. The receive path (Rx) offers a low noise figure (NF) lower than 2.8 dB with 25 dB of linear gain. The Rx port output power leakage is limited on chip to be below 15 dBm even at high compression levels. Finally, a complete characterization of the SCFE in the Rx and Tx modes is presented, also showing the measurement of the recovery time in the presence of large-signal interferences.

Double-crossed radiofrequency coil with improved uniformity for rodent MRI at 7 T

A transceiver volume coil for High Field Magnetic Resonance Imaging was developed based on Temnikov’s NMR probe coil. The critical advantage of this design is that requires only one trimmer capacitor for both tuning and matching. Electromagnetic simulations of our coil were compared to a four-rung birdcage coil to evaluate their performances. A transceiver coil prototype, called the double-cross coil and a birdcage coil were built to compare and contrast their feasibility. Both coil prototypes were operated in the linear mode. Experimental quality factors were Qu/Ql=101/45 for the double-cross coil and Qu/Ql=105/43 for the birdcage coil. Phantom images were acquired to test the viability of each coil for high field magnetic resonance imaging applications. The signal-to-noise ratios, noise factors and uniformity values were also calculated: 85.26/0.74/44.48 for the double-cross coil and 76.54/1.9/65.65 for the birdcage coil. These volume coils showed similar performance, but the double-cross coil has better uniformity and a slightly lower noise figure than the birdcage coil. A remarkable agreement of experimental and simulated B1 was obtained for the double-cross coil. These experimental and numerical results demonstrate the feasibility of the double-cross volume coil with better uniformity for rodent magnetic resonance imaging at 7 T.

An improved cascode common-source LNA with inductive source degeneration for RF applications

This paper presents a novel structure to enhance the power gain (S21) of the conventional cascode common-source (CS) low-noise amplifier (LNA) with inductive source degeneration. The proposed LNA has an extra transistor and a capacitor in comparison with the conventional structure. The additive transistor significantly increases the S21 of the conventional cascode CS LNA with inductive source degeneration with the same DC power consumption (PDC), third-order input intercept point (IIP3), area, and slightly lower noise figure (NF). The utilized capacitor is used to improve the IIP3 of the proposed LNA. The power gain improvement of the proposed LNA has been validated by both theoretical analysis and extensive post-layout simulation results. The proposed and conventional LNAs have been designed in TSMC 180 nm CMOS technology. The post-layout simulation results of the proposed LNA are 2.42 dB NF, S21 of 15.55 dB, and 0.84 dBm IIP3 while consuming 3.2 mW from 1.2 V power supply. The simulated S21 of the proposed LNA is about 2.55 dB (34.2 %) larger than the conventional cascode LNA with the same other performance parameters. Also, the achieved figure-of-merit (FoM) of the proposed LNA is substantially larger than the conventional cascode CS LNA with inductive source degeneration.

A 18–44 GHz Low Noise Amplifier With Input Matching and Bandwidth Extension Techniques

This letter presents a low noise amplifier (LNA) with a 3-dB gain bandwidth (3-dB BW) of 18–44 GHz in 65-nm CMOS technology. By deriving an analytical equation of input impedance, a co-design methodology for the first two stages of LNA that can simultaneously achieve broadband input matching and low noise figure (NF) is implemented. Weakly coupled asymmetric transformers that introduce a section of reverse parallel winding in the primary coil are designed to realize broadband interstage matching, optimize the gain flatness and boost the transconductance. The proposed LNA achieves a measured peak gain of 19.5 dB with a fractional 3-dB gain bandwidth (FBW) of 83.8%, covering the whole <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$K$ </tex-math></inline-formula> -band and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$Ka$ </tex-math></inline-formula> -band. The measured NF is 2.6–3.5 dB from 20 to 43 GHz. To the best of our knowledge, the proposed LNA achieves the highest 3-dB BW and FBW with competitive NF. The measured input 1-dB gain compression point ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text {IP}_{\mathrm {1\,dB}}$ </tex-math></inline-formula> ) ranges from −23 to −18.5 dBm over the entire 3-dB gain bandwidth.

A triple path noise cancellation LNA with transformer output using 45 nm CMOS technology

Abstract A triple path dual resistive feedback noise cancellation (TP-DRNC) low noise amplifier (LNA) with transformer output presented which provides high gain, low noise figure (NF), and high figure of merit (FM). The analysis of triple path, dual resistive, gain, and NF have been discussed. The effect of various components used in the circuit have been analyzed and their optimized values are obtained which resulted in the high (FM). The combination of dual resistive feedback with triple path NC transformer output allowed for low NF and high gain. The proposed GPDK 45 nm complementary metal oxide semiconductor (CMOS) technology-based LNA offers a flat gain curve of 10.81 dB over the range of 1.6 GHz to 4.3 GHz, or 2.7 GHz bandwidth, and S11 less than −9 dB. The input third order intercept point (IIP3) for the given bandwidth has value of 5.7 dBm, while the minimal NF achieved is 2.7 dB; (FM1) is 14.026 and (FM2) is 12.48. The proposed LNA’s layout with an o -chip transformer has an area of 0.01985 mm2

A two stage cascode LNA using modified derivative superposition technique in [formula omitted] HBT with an IIP3 of 2 dBm and NF of 4.8 dB for IEEE 802.11ad standard

A two stage cascode Low Noise Amplifier (LNA) is designed in 130 nm SiGe HBT. The work focuses on achieving a low Noise Figure (NF), high linearity, and high gain for the LNA in the frequency band of 57.24 GHz-65.88 GHz to be operated in all the four channels of IEEE 802.11ad standard. A modified Derivative SuperPosition technique is used in the first stage of the cascaded LNA to improve the linearity of the circuit. Post layout Electromagnetic (EM) simulation results of the proposed LNA achieves a peak gain of 20.19dB at 59.5GHz, linearity (IIP3) of 2dBm at the maximum gain and also achieved a NF of 4.1dB - 4.8dB in the operating band of frequency. DC power consumption of the proposed circuit is 9.2mW from a supply voltage of 1.2V, with an area occupancy of 311μm×298μm.

A Reflectionless Receiver With Absorptive IF Amplifier and Dual-Path Noise-Canceling LNA

This article presents a 22.6–39.2-GHz reflectionless receiver (RX) capable of reducing the in-band intermodulation and high-order mixing products. Such RX consists of an absorptive IF amplifier, a double-balance passive mixer, and a dual-path noise-canceling low noise amplifier (LNA). The absorptive IF amplifier is utilized to suppress the out-of-band signal reflected back to mixer, which can reduce the intermodulation and high-order mixing products caused by the remixing of the out-of-band signals. Meanwhile, the dual-path noise-canceling LNA is used for achieving low noise figure (NF) in a wide frequency range. To verify the aforementioned principle, a reflectionless RX is implemented and fabricated using a conventional 28-nm CMOS technology. The measurement shows the minimum NF of 3.6 dB and the peak input third-order intercept point (IIP3) of −11.7 dBm. Besides, the proposed RX can support multi-Gb/s, 256-quadratic amplitude modulation (QAM)/1024-QAM modulation signals.

Design of compact highly matched broadband balanced low‐noise amplifier at X‐band using CRLH transmission lines

This article presents broadband balanced low-noise amplifier (LNA) operating at X-band, which uses composite right/left-handed (CRLH) transmission lines as input–output matching networks. Proposed LNA eliminates lumped DC-blocking capacitors and is combined with a hybrid coupler to achieve better stability and matching. Presented CRLH matching technique enhances the matching quality, reduces the overall size and considerably improves the bandwidth and noise performance. The matrix analysis of the CRLH structure is provided to determine the exact dimension of microstrip lines for the highest stable gain and the lowest noise figure (NF). The LNA structure uses a HJFET technology as an active device, which is simulated using an ADS momentum and small-signal scattering parameters provided by the manufacturer. This LNA offers an improved impedance matching and measured the 20 dB S11 band-width of 16% (8.3–9.7GHz), which is in good agreement with simulation. Total area occupied by the fabricated LNA is only 1.7 λ 0 × 0.9 λ 0 @ 8.3GHz. The LNA also provides <1.8 dB NF based on the IEEE standard temperature (16.85 Celsius), and 1 dB gain flatness throughout the entire band along with a 1 dB compression point of −1 dBm and an output third point intercept point of 19.5 dBm. The proposed CRLH-based LNA can be a good candidate for compact receivers and sensors.

Low-loss microwave photonics links using hollow core fibres

There are a host of applications in communications, sensing, and science, in which analogue signal transmission is preferred over today’s dominant digital transmission. In some of these applications, the advantage is in lower cost, while in others, it lies in superior performance. However, especially for longer analogue photonics links (up to 10 s of km), the performance is strongly limited by the impairments arising from using standard single-mode fibres (SSMF). Firstly, the three key metrics of analogue links (loss, noise figure, and dynamic range) tend to improve with received power, but this is limited by stimulated Brillouin scattering in SSMF. Further degradation is due to the chromatic dispersion of SSMF, which induces radio-frequency (RF) signal fading, increases even-order distortions, and causes phase-to-intensity-noise conversion. Further distortions still, are caused by the Kerr nonlinearity of SSMF. We propose to address all of these shortcomings by replacing SSMFs with hollow-core optical fibres, which have simultaneously six times lower chromatic dispersion and several orders of magnitude lower nonlinearity (Brillouin, Kerr). We demonstrate the advantages in this application using a 7.7 km long hollow-core fibre sample, significantly surpassing the performance of an SSMF link in virtually every metric, including 15 dB higher link gain and 6 dB lower noise figure.