Power Amplifier - Science topic

In a reciprocal system, all the wave travels in the same way backward as forward. When the exchange between the source and detectors result in different transmittance, non-Hermiticity is granted but the nonreciprocity needs to be carefully evaluated. Although most of the integrated circuits are reciprocal, unexpected nonreciprocal response may emer...

In this article, a linearity-improved millimeter-wave (mm-wave) gallium nitride (GaN) monolithic microwave integrated circuit (MMIC) Doherty power amplifier (DPA) is presented for fifth-generation new radio (5G-NR) FR2 applications. To improve the linearity of the DPA while maintaining high back-off efficiency, a reconfigurable diode-based self-ada...

Phosphorus-doped fiber has great advantages in supercontinuum (SC) generation because it can narrow the gap between Raman-related peaks and valleys owing to its special Raman gain. In this paper, a random fiber laser (RFL) structure and a main oscillator power amplifier (MOPA) structure are used to pump a self-made phosphorus-doped fiber. The resul...

In this paper, a 280–300 GHz hybrid‐integrated transmitter is proposed. The advantages of the SiGe and InP chips are fully made use by integrating these two chips. For low cost and high integration, the local oscillator chain and mixer are based on chips in SiGe technology, and the 300‐GHz power amplifier and on‐chip antenna are realised in InP tec...

Power amplifiers are crucial components that significantly influence the linearity and energy efficiency of next-generation communication system radio units. A key challenge in designing power amplifiers is managing high peak-to-average power ratio (PAPR) in order to achieve both high linearity and energy efficiency during back-off conditions. This...

This brief presents an 11.5–17.5-GHz power amplifier (PA) with 32-dBm output power in a 0.25- $\mu$ m gallium nitride (GaN) process. Capacitively and inductively coupled resonators are used for impedance matching to achieve a flat in-band power gain and a high out-of-band rejection. Meanwhile, the output matching network provides a second-harmonic...

As a power amplifier in nonlinear frequency conversion, semiconductor optical amplifiers around 1 μm can effectively realize the miniaturization of the light source system. In this paper, a low confinement factor anti-waveguide asymmetric super-large optical cavity semiconductor optical amplifier (AT-SLOC-SOA) with high saturation power is reported...

This paper describes an analysis of power supply rejection and noise improvement techniques for an envelope-tracking power amplifier. Although the envelope-tracking technique improves efficiency, its power supply rejection ratio is much lower than that of average power tracking or a fixed-supply power amplifier. In FDD systems with the envelope-tra...

The manuscript presents the design and development of a Microwave Hyperthermia (MHT) applicator integrated with an Electromagnetic (EM) lens. The purpose of the proposed MHT applicator is to provide non-invasive microwave hyperthermia treatment for skin cancer. The proposed MHT applicator comprises of an EM lens (133.75 × 133.75 mm³) placed ahead o...

This review paper examines the advancements in solid-state power amplifiers (SSPAs) for wireless communication technology. As mobile devices rely on efficient power amplifiers to maintain battery life and ensure clear signal transmission, fabrication technologies like Complementary Metal-Oxide-Semiconductor (CMOS) and Gallium Nitride (GaN) are revo...

This paper presents a filtered power amplifier (PA) based on the continuous class‐F mode. This broadband filtering PA employs a terminated coupled line structure, which consists of coupled line segments and four terminations loaded on them for obtaining high efficiency over a wide frequency band. Also, a detailed theoretical analysis and calculatio...

This paper presents a dual-band fully integrated high linearity CMOS power amplifier (PA). The PA employs a reconfigurable transformer in the input matching network to achieve low reflection coefficient across both bands, demonstrating significant flexibility in the design of dual-band power amplifiers with high output powers. Additionally, a detai...

A compact harmonic tuning network (HTN) using a composite right-/left-handed (CRLH) transmission line (TL) is introduced. The CRLH TL offers purely imaginary harmonic load impedances, as it essentially functions as a one-port circuit at the harmonic frequencies, owing to a harmonics trap filter. In comparison to conventional HTNs based on microstri...

One of the main systems of a spacecraft (SC) is the power supply system (PSS). The basis of PDS are secondary power sources (SPS), which use various methods of controlling and converting electricity, which leads to significant differences in their dynamic properties. From the side of on-board consumers, the dynamics of the power transmission system...

This review article investigates the current status and advances in Ku-band gallium nitride (GaN) high-electron mobility transistor (HEMT) high-power amplifiers (HPAs), which are critical for satellite communications, unmanned aerial vehicle (UAV) systems, and military radar applications. The demand for high-frequency, high-power amplifiers is grow...

This paper introduces a new design method for a high‐power density GaN MMIC amplifier operating in the Ku‐band. A thermal model to investigate the thermal distribution of power amplifiers is proposed to achieve optimal performance in terms of power density, chip size, and channel temperature. The thermal distribution and channel temperature of a si...

This manuscript presents a millimeter-wave GaN high-power amplifier (HPA) intended for next generation inter-satellite links (ISLs). The proposed architecture achieves a fractional bandwidth wider than 18% in the V-band spectrum, to deliver a 10 Gbit/s throughput compatible with multi-thousand-km ISLs. Core of the HPA is the monolithic microwave in...

Piecewise linearization techniques require dividing the signal into multiple pieces each linearized individually. Machine learning (ML) is one of the useful tools to perform the automatic division of these pieces. Complexity reduction in the classification of piecewise digital predistortion is possible through carefully constructing features from b...

The Internet of Vehicles (IoVs) has seen rapid development due to advances in advanced communication technologies. The 5-th Generation (5G) systems will be integrated into next-generation vehicles, enabling them to operate more efficiently by cooperating with the environment. The millimeter Wave (mmWave) technology is projected to provide a large b...

A broadband 28 nm complementary metal–oxide–semiconductor (CMOS) power amplifier was implemented using a distributed amplification design. To develop a model library for high-frequency design, various test patterns for active and passive elements were fabricated and compared through measurements. As a result, a symmetrical n-channel field-effect tr...

In an advanced waveform, a lower PAPR is essential for reducing power amplifier non-linearities and enhancing system performance. An overview of PAPR reduction techniques is provided in this abstract for three widely used modulation schemes in optical and wireless communication systems: optical-orthogonal Frequency Division Multiplexing (O-OFDM), o...

Synopsis Volume coils such as the Birdcage Coil possess homogeneous magnetic fields due to circularly polarized fields assisted by the Hybrid Coupler. To perform the complete operation of the birdcage coil for imaging, the Transmit power must be well isolated from the receive front end which is done by introducing RF switches in the receive path. H...

This paper provides the details of a novel systematic design methodology for two-way in-phase filtering Gysel splitter/combiner networks with high selectivity, which finds application in high power amplifier modules. It simultaneously realizes a filtering function and a two-way splitter/combiner function. The proposed five-port filtering device, ba...

In this paper, a high-efficiency compact power amplifier is designed and fabricated with a 0.25 μm GaN high electron mobility transistor (HEMT) to meet the demands of a high integration level and high efficiency for microwave wireless power transfer (WPT) systems. The proposed power amplifier (PA) is implemented using an internally matched method t...

This paper presents a novel methodical approach to hybrid modulators (HMs) design used in providing variable power supply (VPS) for Power Amplifiers. Theory of operation and different design considerations affecting HMs design procedure are discussed. This paper proposes a new approach to using inductors in HMs by integrating them on-chip instead o...

This article introduces a novel design methodology of a re-configurable tri-band matching network along with Power Amplifier (PA) that supports the latest WLAN applications. The implemented matching network/circuit, specifically designed for the 2.4 GHz band, enables amplifier to achieve a linear power exceeding 11 dBm. Incorporating the proposed m...

Utilizing long-wavelength laser diodes (LDs) for pumping to achieve high-power fiber laser output is an effective method for attaining high quantum efficiency and excellent thermal management. In this work, we report on a Master Oscillator Power Amplifier (MOPA)-structured long-tapered Yb3+-doped fiber laser directly pumped by long-wavelength laser...

This paper studies the physical-layer security (PLS) improvement in wireless communication systems, where a hybrid reconfigurable intelligent surfaces (RISs) is deployed between the transmitter and legitimate receiver to enhance the communication security. To achieve a tradeoff between the secrecy capacity and power consumption, the element on-off...

span>The wireless communication networks in the smart grid’s advanced metering infrastructure (AMI) applications need 5G technology to support large data transmission efficiently. As the 5G wireless communication network’s overall bandwidth (BW) and efficiency depend on its power amplifier (PA), in this work, a two-stage class-J power amplifier’s d...

In this letter, we propose a novel self-interference (SI) cancellation solution for asymmetric in-band full-duplex (IBFD) systems, where the downlink (DL) signals are noncontiguously aggregated within the available band. The method builds on a Hammerstein model with parallel spline-interpolated 2-D lookup tables (LUTs), together with efficient grad...

This article presents a 23-GHz transmitter/low-noise amplifier (TX/LNA) front-end module (FEM) in 130-nm SiGe BiCMOS for inter-satellite links (ISLs) in the system of orbiting low-frequency antenna array (OLFAR). The FEM consists of an LNA, a power amplifier (PA), a variable-gain amplifier (VGA), a phase shifter (PS), and a TX/receiver switch (T/R...

RF power amplifier (RF PA) finds its application in almost all the areas of electronics, mobile communication being identified as a major area. The paper performs a comparative efficiency analysis of RF power amplifiers operating with a fixed bias and an envelope tracking bias. Simulations are performed using Keysight advanced design system (ADS) t...

In this paper, we present a high power-added efficiency (PAE) and high gain per stage 60 GHz power amplifier (PA). The proposed PA consists of a two-stage common-source amplifier that incorporates neutralization capacitors and compensation inductors to enhance both gain and efficiency. The gain characteristics are analyzed, demonstrating that the p...

This paper proposes a Composition Piecewise Memory Polynomial (CPMP) digital predistortion model based on a Vector Switched (VS) behavioral model to address the challenges of severe nonlinearity and strong memory effects in wideband power amplifiers (PAs). To tackle this issue, two thresholds are calculated and used to segment the envelope values o...

Orthogonal Time Frequency Space (OTFS) is regarded as one of the best contenders for sixth-generation (6G) radio systems due to its ability to obtain excellent performance in high-speed scenarios. Peak-to-average power ratio (PAPR) significantly impacts and degrades the efficiency of the power amplifier used in OTFS-based 6G systems. The proposed a...

CVBs (cylindrical vector beams) are widely used in optical imaging, optical trapping, material processing, etc. In this study, based on mode-selective couplers and passive mode-locking fiber technology, a cylindrical vector fiber amplifier with an MOPA (master oscillator power amplifier) structure was developed. In the experiment, the pre-amp stage...

This paper studies the performance of the communication link between a ground station and the satellites of a LEO constellation, employing code division multiplexing and a non-linear high-power amplifier. The analysis shows that the input power selection at the high-power amplifier of the ground station has a significant impact on overall system pe...

In this paper, we study the joint effects of timing offset (TO), carrier frequency offset (CFO), phase noise (PN), and nonlinear power amplifier distortion on a generalized frequency division multiplexing (GFDM) system. Classifying the TO into four cases based on the direction of offset, our work analyzes the signal-to-interference ratio (SIR) for...

This paper presents a Doherty power amplifier (DPA) integrated circuit (IC) designed to have enhanced gain, efficiency, and AM-AM characteristics through a dynamic power dividing technique, which can control the power dividing ratio according to the input power. Since this multi-purpose dynamic power dividing network also provides the phase offset...

A high-sensitivity spin exchange relaxation free (SERF) atomic magnetometer based on a noise-suppressed master oscillator power amplifier (MOPA) system is demonstrated. The spectrum and frequency noise of the laser are measured and it is proved that the frequency noise in the MOPA system is affected by the amplified spontaneous emission (ASE) stimu...

In this Letter, we demonstrate a single-stage erbium-doped fluoride fiber amplifier composed of two spliced large core fibers with respective diameters of 85 and 130 µm. An optical parametric generator (OPG) operating at a 5 kHz repetition rate, and providing ∼2 ns pulse duration, and an average output power of 500 mW at a wavelength of 2.8 µm was...

This article presents an integrated quadrature balanced power amplifier (PA) operating at a 26-GHz frequency range and techniques to mitigate the frequency-dependent amplitude response of quadrature hybrids used in the balanced amplifier design. The overall structure consists of two stacked pseudo-differential PAs and transformer-based quadra-ture...

Orthogonal time frequency selectivity is considered one of the most promising advanced waveforms for high-mobility conditions in beyond-fifth-generation networks. A high peak-to-average power ratio in orthogonal time frequency introduces nonlinearity and degrades the power amplifier performance. In this work, we propose a novel automatic amplitude...

A novel spoof surface plasmon polaritons (SSPP) structure is applied to the design of radio frequency (RF) power amplifiers (PAs) in this work. Both standard SSPP and the proposed SSPP structures are used as input and output matching networks of a multioctave PA design. An analysis and discussion of the electromagnetic characteristics of the propos...

Objective. In magneto-acousto-electrical tomography (MAET), linearly frequency-modulated (LFM) signal stimulation uses much lower peak voltage than the spike pulse stimulation, lengthening the operation life of the transducer. However, due to the uneven frequency responses of the transducer, the low-noise amplifier (LNA), and the bandpass filter (B...

Lamb waves have become a focal point in ultrasonic testing owing to their potential for long-range and inaccessible detection. However, accurately estimating the flaws in plates using Lamb waves remains challenging because of scattering, mode conversion, and dispersion effects. Recent advances in laser ultrasonic wave techniques have introduced inn...

This paper presents a comprehensive study on the design and performance of a high-power amplifier (PA) covering a broad frequency band from 0.1 to 4.8 GHz. Leveraging a 10 W GaN device, the amplifier achieves output power levels surpassing 10 W across the entire frequency band. Furthermore, the power-added efficiency (PAE) of the amplifier ranges f...

Reconfigurable Intelligent Surface (RIS) is a promising technology that may effectively improve the quality of signals in wireless communications. In practice, however, the ``double fading'' effect undermines the application of RIS and constitutes a significant challenge to its commercialization. To address this problem, we present a novel 2-bit pr...

This paper presents a 9-mW ultrasonic through-transmission transceiver (TRX) for portable, non-invasive intracranial pressure (ICP) sensing. It employs two ultrasound transducers placed at the temporal bone windows to measure changes in the ultrasonic time-of-flight (ToF), based on which the skull expansion and the corresponding ICP waveform are de...

An efficient and linear power amplifier (PA) for millimeter wave applications using a 130nm CMOS process is presented in this paper. The proposed PA uses transformer coupling for output, inter-stage, and input matching and also utilizes inter-stage inductors to boost RF achievement. The Ansoft high-frequency structure simulator (HFSS) is used to an...

A fully integrated gallium arsenide (GaAs) heterojunction bipolar transistor (HBT) power amplifier (PA) for wireless local area network 802.11ax applications is presented in this paper. The structure consists of two‐stage power cells. To satisfy the high linearity requirements of IEEE 802.11ax, we analyzed the distortion of amplitude‐to‐amplitude a...

This paper introduces a novel differential combiner designed to effectively address parasitic capacitances of transistors used in power amplifier (PA) designs with precise compensation at a specified frequency. The combiner consists of a λ/4 transmission line with an integrated capacitor of value 2COUT at its midpoint, which ensures accurate cancel...

This paper outlines a design approach for biomedical wireless power transfer systems with a focus on three-coil inductive links for neonatal intensive care unit applications. The relevant literature has been explored to support the design approach, equations, simulation results, and the process of experimental analysis. The paper begins with a brie...

In this paper, a high-power amplifier is designed to address the challenges of low transmission power and poor efficiency in wireless energy transmission technology at low frequencies. The design is based on a class E power amplifier circuit. The theoretical analysis is conducted to determine transistor selection and the static DC operating point....

In this paper, high Er³⁺ concentration erbium doped fiber (EDF) and erbium-ytterbium co-doped fiber (EYDF) were fabricated for the seed and master oscillator power amplifier (MOPA) system of the single-frequency fiber laser. An in-band pumping source with the wavelength of 1535 nm was proposed to improve the efficiency in the ring-cavity. A slope e...

The purpose of this paper is to present a detailed design procedure for a highly efficient sequential load-modulated balanced amplifier (SLMBA) to provide an in-depth analysis of this complex power amplifier (PA) architecture. SLMBA’s basic theory is presented and discussed. An SLMBA with a frequency range from 2.45 GHz to 2.65 GHz was implemented...

Due to the consequences of fires, new and environmentally friendly firefighting techniques are constantly being sought. There are many methods of extinguishing flames around the world. One of them is a technique that uses acoustic waves for extinguishing, which can be seen as repeated sequences of molecular compression and dilation (acoustic waves...

This paper presents a thorough robust Class-AB power amplifier design and its application in pressure-mode sensor-on-chip nonlinearity correction. Considering its use in piezoresistive sensing applications, a gain-boosting-aided folded cascode structure is utilized to increase the amplifier’s gain by a large amount as well as enhancing the power re...

In the context of Long-Term Evolution (LTE) applications, Single Carrier Frequency Division Multiple Access (SC-FDMA) has emerged as a promising alternative due to its advantageous properties in power efficiency and spectral utilization. However, one of the significant challenges in SC-FDMA systems is the high Peak-to-Average Power Ratio (PAPR), wh...

The signal with high spectral efficiency tends to suffer from high peak-to-average power ratio (PAPR), which significantly reduces the achievable power amplifier efficiency. Therefore, it is important to investigate the statistical properties of band-limited signals in terms of their dynamic range. On the other hand, the out-of-band (OOB) emissio...

This is our last release in 2024 and closes off our fourth year of publications. As we enter 2025, we will be scheduled for bimonthly, rather than quarterly, issues as we take advantage of a significant increase in paper submissions after receiving our Clarivate Journal Impact Factor of 6.9. Our October issue contains 14 regular papers and one invi...