Noise Figure Degradation Research Articles

Enhancement of single-photon level signal detection based on phase sensitive amplification strategy

Abstract We investigate the ability of phase-sensitive amplification (PSA) to noiselessly amplify the preferred quadrature components of single-photonsignals that are limited by phase fluctuations relative to the pump. We presenta PSA enhancement strategy that is more realistic for possible experimentalrealization and is expected to significantly improve the detection of weaksignals at the single-photon level and obtain more useful information. Our studyshows that with a large PSA gain, proper transmissivity allows both direct and
balanced homodyne detections to operate optimally simultaneously, and effectively improves the noise figure degradation owing to the internal losses and non-ideal detection efficiency.

Robust GaN-Based LNAs With Active Epitaxial Current Limiters

In this letter, the current limiters fabricated by the gallium nitride (GaN) active epitaxial layers are introduced to achieve GaN-based robust low-noise amplifiers (LNAs). In principle, by taking advantage of the current saturation effect, the gate dc current which causes gate degradation or breakdown can be controlled below the breakdown limit at any input level. The active current limiter can also reduce the ON-state degradation by reducing the drain current. Two designs of robust LNAs in the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Ka</i> -band are presented. The LNA1 has current limiters in gate regions, and the LNA2 has current limiters in both gate and drain regions. Both LNAs survive in a 1-h stress experiment with 32–30.5-dBm input power. After the stress experiment, both LNAs show little degradation in noise figure, and the LNA2 shows little degradation in gain because of the drain current limiter.

A 20–42-GHz IQ Receiver in 22-nm CMOS FD-SOI With 2.7–4.2-dB NF and −25-dBm IP1dB for Wideband 5G Systems

This article presents a 20–42-GHz in-phase and quadrature (IQ) receiver in 22-nm CMOS fully depleted silicon on insulator (FD-SOI). The receiver includes a wideband low noise variable-gain amplifier (LN-VGA), double-balanced IQ mixers, wideband I/Q generation network and wideband local oscillator (LO) driver, low-pass filters, and wideband intermediate frequency (IF) amplifiers. The measured receiver has a peak conversion gain of 25.3 dB with a 3-dB bandwidth of 19.8–42 GHz and an I and Q bandwidth of 5.7 GHz and covers the 5G millimeter-wave (mm-wave) band. The measured single-sideband noise figure (NF) is 2.7–4.2 dB at 24–42 GHz with an IP1dB of −26 to −23 dBm. The I/Q downconverter consumes a total of 102 mW from 0.8- and 1.6-V supplies. The IP1dB can be improved by 5 dB with an NF degradation by only 1.2 dB using RF VGA gain control. At peak gain and −8-dB VGA setting, the receiver dynamic range is 64–68 dB for a 100-MHz bandwidth, which is very high for low power consumption. The gain and phase mismatch between the I and Q channels is < 0.6 dB and <6°, respectively. To the best of the authors’ knowledge, this is the first wideband I/Q receiver that covers the entire mm-wave 5G band based on GF 22-nm CMOS FD-SOI. The application area is multistandard multigigabit per second communication systems.

A 65 nm CMOS Quadrature Balanced Switched-Capacitor Power Amplifier for Full- and Half-Duplex Wireless Operation

This article proposes a multi-mode wireless transmitter for full-duplex (FD) and half-duplex (HD) operation based on a quadrature balanced switched-capacitor power amplifier (QB-SCPA) architecture in 65 nm CMOS. The QB-SCPA provides inherent passive transmit–receive (TX–RX) isolation along with an embedded digital self-interference cancellation (SIC) signal injection mechanism and exhibits excellent TX and RX linearity characteristics. To minimize noise figure degradation to the RX path, local oscillator (LO) signal sharing between the two SCPAs comprising the transmitter and a retiming circuit that generates the 25% clock signals is employed to obtain phase noise suppression at the LNA port. In the FD mode, 50 dB of SIC is demonstrated across the instantaneous bandwidth of a 20 MHz orthogonal frequency-division multiplexing (OFDM) signal with 11 dB peak-to-average power ratio (PAPR), along with −35 dB TX error vector magnitude (EVM) with SIC ON and without digital predistortion. The transmitter achieves a maximum output power of 23 dBm with 26.5% power-added efficiency (PAE) and 21 dBm with 17.4% PAE in HDTX and FD modes, respectively, and has a wide operating bandwidth between 1.5 and 3 GHz.

Experimental investigation on the degradation of SiGe LNAs under different bias conditions induced by 3 MeV proton irradiation

The 3 MeV proton irradiation effects on SiGe low noise amplifier (LNA) (NXP BGU7005) performance under different voltage supply VCC (0 V, 2.5 V) conditions were firstly experimental studied in this present work. The S parameters including S11, S22, S21, 1 dB compression point and noise figure (NF) of the test samples under different bias voltage supply were measured and compared before and after 3 MeV proton irradiation. The total proton irradiation fluence was 1 × 1015 protons/cm2. The maximum degradation quantities of the gain S21 and NF of the test samples under zero bias are measured respectively 1.6 dB and 1.2 dB. Compared with the samples under 2.5 V bias supply, the maximum degradation of S21 and NF are respectively 1.1 dB and 0.8 dB in the whole frequency band. It is noteworthy that the gain and NF of SiGe LNAs under zero-bias mode suffer enhanced degradation compared with those under normal bias supply. The key influence factors are discussed based on the correlation of the SiGe device and the LNA circuit. Different process of the ionization damage and displacement damage under zero-bias and 2.5 V bias voltage supply contributed to the degradation difference. The underlying physical mechanisms are analyzed and investigated.

An Active Leakage Canceller Adopting Switched-Capacitor Digital Power Amplifier for UHF-RFID Transceiver

A low-noise active leakage canceller (ALC) for radio frequency identification (RFID) transceiver is reported. The proposed ALC suppresses the strong transmitter (TX) leakage at the receiver (RX) input through continuous leakage tracking by employing an I/Q harmonic rejection switched-capacitor digital power amplifier (I/Q HR SC DPA). Compared to the analog feedback loop-based ALC, the proposed ALC minimizes the noise figure (NF) degradation in the RX and eliminates the large-size passive components in the analog low pass filter, which leads to high RX sensitivity and small chip area. Implemented in a 55-nm CMOS, the proposed ALC suppresses -10 dBm TX leakage down to -47.2 dBm while degrading the RX NF by 0.4 dB at the offset frequency of 640 kHz.

A magnetic‐free in‐band full‐duplex RF front‐end with antenna balancing structure

In this article, a design of magnetic-free in-band full-duplex (IBFD) RF front-end with antenna balancing structure is presented. The proposed magnetic-free IBFD RF front-end consists of 3 dB hybrid couplers, a Wilkinson power divider, two transmitter (Tx) antennas, and two receiver (Rx) antennas. The proposed IBFD RF front-end can be implemented and integrated at high frequencies because all the components used in the circuit are non-magnetic devices. Proposed IBFD RF front-end eliminated the 3-dB Tx insertion-loss of the Balun and transformer in conventional IBFD RF front-ends using antenna balancing structure. Moreover, there is no noise figure degradation at Rx because it realized only a passive circuit. The mathematical analysis of the cancellation characteristics between two different signals with magnitude and phase difference variations according to the normalized frequencies is presented. Accordingly, the broadband out-of-phase balancing power splitter and the antenna balancing structure are adopted to achieve broadband SIC. In order to verify the electrical performances of the proposed magnetic-free IBFD RF front-end, it was implemented at the 2.5 GHz WiMax frequency band. When the fabricated IBFD RF front-end was operated with antenna balancing structure, the measurement results show that the 60 dB SIC bandwidth and maximum SIC were 113 MHz (2.446 - 2.559 GHz) and 75.6 dB, respectively.

A 0.2~3.8-GHz Full-Duplex Receiver With More Than 25 dB Self-Interference Cancellation Using a C-DAC-Based Vector Canceller

This paper presents a $0.2\sim 3.8$ -GHz in-band (IB) full-duplex (FD) mixer-first receiver based on a vector self-interference (SI) canceller. To ensure the wideband orthogonality of the reconstructed SI signal while minimizing the noise figure (NF) degradation in FD mode, a low insertion loss two-stage polyphase filter (PPF) with a lacking resistance and capacitance (LRC) structure is used in the SI canceller. A 6-bits passive capacitor digital to analog converter (C-DAC) attenuator not only realizes the high-precision amplitude adjustment of the reconstructed SI signal but also avoids the linearity limitation of the back-end modules of the canceller and reduces the noise contribution of the front-end modules at the canceller output. A four-phase mixer-first receiver with enhanced out-of-band (OOB) interference suppression is designed to provide sufficient linearity to reduce the SI-induced nonlinear distortion. As a proof of concept, a prototype FD receiver is fabricated in CMOS 65 nm technology and measured in chip-on-board (COB) package. Measurement results show that it can operate in the frequency range of $0.2\sim 3.8$ -GHz with more than 25 dB SIC amount for 10 MHz bandwidth (BW) 64-QAM modulated signals in fixed (30 dB) channel attenuation test setup. The receiver achieves OOB input-referred third-order intercept point (OOB-IIP3) of +24 dBm and OOB input-referred second-order intercept point (OOB-IIP2) of +82 dBm at 1-GHz local oscillator (LO) frequency. In FD mode, the NF degradation is $\leqslant 1.5$ dB. The effective IB-IIP3 and effective IB-IIP2 are enhanced by 15 dB and 28 dB, respectively. The power consumption of entire FD receiver including the SI canceller is less than 44 mW. The active chip area is 0.55 mm2.

A Survey and Quantitative Evaluation of Integrated Circuit-Based Antenna Interfaces and Self-Interference Cancellers for Full-Duplex

Full-duplex (FD) wireless - simultaneous transmission and reception on the same frequency - is a promising technique that can significantly improve spectrum efficiency and reduce communication latency in future wireless networks. To enable FD operation, the powerful self-interference (SI) signal leaking from the transmitter (TX) into the receiver (RX) needs to be suppressed and canceled to an extreme degree at the antenna interface as well as in the RF/analog and digital domains. Various approaches to achieve TX-RX isolation at the antenna interface and SI cancellation (SIC) in the RF/analog and digital domains have been demonstrated, with a focus on using bench-top off-the-shelf components. Recent advances in integrated circuit (IC) implementations of various types of shared antenna interfaces and cancellers in the RF and/or analog baseband (BB) domains have further pushed the frontier of realizing FD wireless in small-form-factor/hand-held devices. Moreover, it is still important to fundamentally study the SIC performance that can be achieved by different types of cancellers. In this paper, we present a first-of-its-kind comprehensive overview on the implementation and comparison of various state-of-the-art integrated shared antenna interfaces and SI cancellers in both the RF and analog BB domains. We define two figures of merit (FOM) for the IC-based shared antenna interfaces and SI cancellers, which capture various design considerations and performance tradeoffs including the achievable isolation/SIC, bandwidth, noise figure degradation, TX/SI power handling, and power consumption. In particular, we focus on two types of integrated shared antenna interfaces including electrical-balance duplexers and circulators. We also discuss two types of SI cancellers based on the time-domain and frequency-domain approaches, which respectively employ parallel delay lines and bandpass filters to emulate the SI channel. Based on realistic measurements, we perform extensive numerical evaluations to illustrate and compare the achievable RF SIC performance in different scenarios, as well as discuss various design tradeoffs. Finally, we provide an overview of the IC-based implementations and performance evaluations of both types of cancellers based on our recent work.

A Mixer-First Receiver With Enhanced Matching Bandwidth by Using Baseband Reactance-Canceling LNA

A mixer-first receiver (RX) with enhanced matching bandwidth (BW) is proposed. The enhanced matching BW is achieved by exploiting the input reactance (negative capacitance) exhibited in resistive feedback voltage-voltage low-noise amplifiers (LNAs), to create a second-order baseband impedance without any power or noise penalty. The technique is analyzed based on a linear time-invariant (LTI) model. An integrated 8-phase mixer-first RX prototype was fabricated in the TSMC 65-nm CMOS process as a proof of concept. The RX is capable of broadband operation and achieves wideband <; -10-dB matching of 40 MHz, with 36-dB RX gain, noise figure (NF) of 2.2-4.2 dB, B1dB of 14.5 dBm, out-of-band (OOB) IIP3 of 33 dBm, and 1-dB NF degradation for 5-dBm blocker power, at a frequency range of 0.5-2 GHz.

Design and Analysis of Enhanced Mixer-First Receivers Achieving 40-dB/decade RF Selectivity

A “second-order” passive mixer-first receiver is proposed to improve channel selectivity, linearity, and noise figure (NF) in the presence of out-of-band blockers, by presenting an impedance that rolls off at 40 dB/decade as the load to an N-path filter. The synthesis of this impedance is described in a step-by-step manner starting from the required impedance transfer function to its actual circuit realization. Various tradeoffs and limitations of the architecture are described in detail, and layout-related techniques are also provided. Two integrated circuit prototypes were fabricated in 28-nm bulk CMOS as proof of concept for this circuit, including a low-power version. The receiver, capable of broadband operation from 0.2 to 2 GHz, achieves an out-of-band IIP3 of +33 dBm and a blocker P1dB of +12 dBm. Additionally, it achieves an NF of 4.4 dB with less than 2-dB degradation in NF for a 0-dBm blocker.

Systematic experimental analysis of an optical sensing microwave low‐noise amplifier

This study presents a systematic experimental analysis of the noise figure and the gain of an optical sensing low-noise amplifier (LNA) in the X-band region (8.5–10.5 GHz). The study has been carried out with the purpose of analysing the effects of a 635 nm optical radiation on the gain and noise figure of the LNA, by modifying the bias operating points. Upon varying the bias conditions from those suggested into the component datasheet towards the device pinch-off, the role of the light exposure changes from causing degradation of the gain and noise figure into a clear performance enhancement. In the middle, a bias condition is found where the above LNA parameters become unresponsive to light exposure. Whilst the detrimental role played by the strong gate current increase under light exposure on the noise figure degradation is already clear, the experimental results show that close to pinch-off this effect is completely overcome by the drain current and transconductance increases.

A 0.1–0.95 GHz Full-Duplex Receiver With &lt; 1 dB NF Degradation Using a Passive Continuous-Mode Charge-Sharing Vector Modulator

This paper presents a frequency-agile in-band full-duplex (FD) receiver based on a switched-capacitor continuous-mode vector modulator (VM). The passive VM presented in this paper provides simultaneous downmixing, attenuation, and phase shifting and is used to generate a baseband canceler signal for self-interference (SI) cancelation. A prototype FD receiver is implemented in CMOS 130 nm technology. The receiver is tunable from 0.1 to 0.95 GHz. In FD mode at 900 MHz, the receiver has an effective input-referred third-order intercept power (IIP3) of +7 dBm, SI-to-noise-and-distortion-ratio (SINDR) of ≈ +65.3 dB at −27.5 dBm SI in 15 MHz bandwidth, and noise figure (NF) degradation of less than 1 dB.

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

AbstractThis 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.

A Comparative Analysis of Dual-Order Bidirectional Pumping Schemes in Optical Fiber Raman Amplification

Abstract In this paper, dual-order bidirectional pumping schemes of distributed fiber Raman amplifier are compared with standard first-order pumping in wavelength division multiplexed optical transmission systems. The novel comparison analysis is carried out in terms of Optical signal-to-noise ratio and Q-factor, on-off gain and noise figure by varying optical input power and fiber lengths. The results indicate that dual-order schemes present 0.02 dB higher OSNR and 5 dB higher Q-factor in comparison to first-order pumping when input optical power is varied from −4 to 5 dBm. Similarly, there is 4 dB higher on-off gain with dual order comparatively to first order when fiber length varied from 10 to 100 km. However, there is degradation in noise figure and Q-factor due to DRBS noise with dual-order pumping when fiber length from 10 to 100 km. Further, the signal power evolutions along fiber length show that there is 5 dBm improvement for 100 km fiber. The novelty of the work is that comparative analysis exhibits improvement in OSNR, on-off gain and Q-factor using dual-order bidirectional pumping.

A Millimeter-Wave Polarization-Division-Duplex Transceiver Front-End With an On-Chip Multifeed Self-Interference-Canceling Antenna and an All-Passive Reconfigurable Canceller

A millimeter-wave (mm-wave) polarization-division-duplex (PDD) transceiver (TRX) front-end with an on-chip multifeed self-interference-canceling (SIC) antenna and an all-passive reconfigurable RF canceller is presented in this paper. The SIC antenna offers several advantages over existing silicon-based antenna-domain self-interference cancellation approaches, such as electrical-balance duplexer, antenna pair, and non-reciprocal circulator. First, it inherently provides a high transmitter (TX)–receiver (RX) isolation with an instantaneously broad bandwidth. Second, there is no additional signal loss at the TX output or RX input, and thus, there is no TX output power/efficiency or RX noise figure degradation by using the multifeed SIC antenna. Third, the SIC antenna only occupies a single antenna footprint, which is compatible with future array-based multi-input-multi-output (MIMO) operation. An all-passive reconfigurable RF canceller is also integrated on-chip to further clean up the residue self-interference (SI) and relax the downstream RX, e.g., analog-to-digital converter (ADC), dynamic range requirement. The all-passive canceller has zero dc power consumption and provides nearly orthogonal amplitude and phase tunability for fast cancellation optimization in practice. In the measurements, the PDD TRX front-end achieves >35-dB antenna-domain SIC at 60–75 GHz, and >60-dB total front-end SIC at 63–65 GHz. Without any off-chip digital-domain SIC, direct horn antenna-to-chip and first-reported chip-to-chip PDD wireless links are demonstrated with multi-Gb/s 16-QAM/64-QAM signal as the target RX signal, while the TX SI uses the same modulation scheme and rate at the same carrier frequency but with independent pseudorandom bit sequence (PRBS) data.

Light activation of noise at microwave frequencies: a study on scaled gallium arsenide HEMT's

This study is focused on the experimental investigation of noise at microwave frequencies for scaled gallium arsenide high-electron-mobility transistor's (HEMT's). The light activation of noise has been achieved by laser exposure in the visible range. The devices have 0.25 μm gate length and 100-200-300 μm gate widths. Their DC characteristics, linear scattering and noise parameters were measured both in dark condition and under continuous wave light exposure in the 2-18 GHz frequency range. Previous results had shown a remarkable influence on all the above-measured parameters under illumination, with a special concern for the noise performance. Therefore, the authors investigated the origin of this light-activated noise in terms of the intrinsic noise sources, by extracting a noise temperature circuit model for each HEMT.In addition, the noise model formulation based on the P, R and C as well as the K g , K r and K c coefficients is used to enlighten the key aspects of the optically activated noise on the device performance. It is observed that the degradation of the minimum noise figure can be attributed to the noise coefficient R, related to the gate noise source that is strongly affected by the charge generation related to light exposure.

Transmitter leakage cancellation technique for CMOS SAW-less radio front-ends

A novel method of transmitter (TX) leakage cancellation is presented to improve the dynamic range of the receiver for wideband code division multiple access applications. The large TX leakage is attenuated within the low noise amplifier (LNA) output using a feed-forward path without any LNA noise figure degradation. A prototype has been designed and laid out in 0.18 μm CMOS technology. It achieves a maximum TX rejection of 18.5 dB with only 5.2 mA current consumption from 1.8 V supply voltage. LNA P-1dBCP (1 dB gain compression point) against TX leakage improves by more than 10 dB. Post layout simulations verify these results. Proposed structure dispels the requirement of off-chip surface acoustic wave filter.

Noise Figure Degradation in Balanced Amplifiers

Balanced amplifiers suffer from the noise figure performance in comparison with a stand-alone amplifier even with an ideal input divider. The noise parameters degrade further with an imperfect divider. We present exact and approximate analytical results for the noise figure and noise parameters of the balanced amplifier in divider topology. Measurement results are also presented as a verification.

Analysis and Design of Integrated Active Cancellation Transceiver for Frequency Division Duplex Systems

An active transmitter (TX) cancellation scheme enabling integration of the antenna interface for frequency division duplex systems is presented. A replica of the TX current is synthesized in shunt with the receiver (RX) by a digital-to-analog converter (DAC). The replica DAC virtually shorts out the TX signal at the RX input while having minimal impact on the TX insertion loss. Propagation of the TX phase noise in the RX band is analyzed and shown to be feed-forward cancelled in the proposed system. A prototype chip including integrated TX, measurement RX, and cancellation circuits, operating on a single-shared antenna, is implemented in 65-nm CMOS. The cancellation replica demonstrates > 50 dB cancellation of a +12.6 dBm peak 20-MHz TX signal across a wide range of center frequencies and up to 5:1 voltage standing-wave ratio at the antenna interface. The RX is able to down-convert the RX signal at 40-MHz offset with < 4.3 dB noise figure degradation in the presence of the residual TX signal.