Artigos de revistas: "Power amplifiers"

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Wang, Haishuo, Tiancheng Yu e Zhe Yang. "Design and output spectral peak power optimization of E-band fiber-amplified spontaneous emission spectra". Highlights in Science, Engineering and Technology 72 (15 de dezembro de 2023): 624–31. http://dx.doi.org/10.54097/4w1mdt53.

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Fiber optic amplifiers will improve the power of signals propagating in optical fibers, usually using doped ions as amplifiers. The bismuth-doped fiber amplifier can amplify the current E-band signal light, which is less used, and provide a solution to enhance the communication transmission capacity.In this essay, Matlab is used as a research tool, and the bismuth-doped fiber amplifier is selected, and the energy level system is a three-energy levelThe 830 nm-wavelength pumping source amplifies the signal light at 1390 nm. The bismuth-ion velocity and power amplification propagation equations are established, and the amplified spontaneous radiated optical power is calculated. Amplified spontaneous radiation optical power, and through the calculation and simulated annealing algorithm to derive the amplified spontaneous radiation optical power amplification with the doping concentration and fiber length spectrum, in the fiber length of 3.3m and the number of doped particles of 9.1 * 10^25 to obtain the maximum optical power of 7.95*10^-9W.

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Mei, Shangming, Yihua Hu, Hui Xu e Huiqing Wen. "The Class D Audio Power Amplifier: A Review". Electronics 11, n.º 19 (9 de outubro de 2022): 3244. http://dx.doi.org/10.3390/electronics11193244.

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Class D power amplifiers, one of the most critical devices for application in sound systems, face severe challenges due to the increasing requirement of smartphones, digital television, digital sound, and other terminals. The audio power amplifier has developed from a transistor amplifier to a field-effect tube amplifier, and digital amplifiers have made significant progress in circuit technology, components, and ideological understanding. The stumbling blocks for a successful power amplifier are low power efficiency and a high distortion rate. Therefore, Class D audio amplifiers are becoming necessary for smartphones and terminals due to their power efficiency. However, the switching nature and intrinsic worst linearity of Class D amplifiers compared to linear amplifiers make it hard to dominate the market for high-quality speakers. The breakthrough arrived with the GaN device, which is appropriate for fast-switching and high-power-density power electronics switching elements compared with traditional Si devices, thus, reducing power electronic systems’ weight, power consumption, and cost. GaN devices allow Class D audio amplifiers to have high fidelity and efficiency. This paper analyzes and discusses the topological structure and characteristics and makes a judgment that Class D amplifiers based on GaN amplifiers are the future development direction of audio amplifiers.

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Kharis, Muhamad, Dhidik Prastiyanto e Suryono Suryono. "Perbandingan Efisiensi Daya Penguat Audio Kelas AB dengan Penguat Audio Kelas D untuk Keperluan Sound System Lapangan". Jurnal Teknik Elektro 10, n.º 2 (19 de dezembro de 2018): 54–58. http://dx.doi.org/10.15294/jte.v10i2.11183.

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Class AB audio amplifiers are commonly used but the efficiency is 50%. While the efficiency of class D audio amplifiers is 90% but are rarely used. The purpose of this research is to know how much the power efficiency of field sound system between 1000 watts class AB amplifier and 900 watts class D amplifier. This study is a comparative study that compares different variables with the same sample. The results of power efficiency are obtained from the percentage comparison between the output power and the input power of each audio amplifier. The power efficiency of class D audio amplifiers with IRS D900 type larger than class AB audio amplifiers with Apex B500 type. The efficiency value of class D audio amplifiers at the highest output power reaches 87% while class AB audio amplifiers are only 73%.

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Choi, Ui-Gyu, e Jong-Ryul Yang. "A 120 W Class-E Power Module with an Adaptive Power Combiner for a 6.78 MHz Wireless Power Transfer System". Energies 11, n.º 8 (10 de agosto de 2018): 2083. http://dx.doi.org/10.3390/en11082083.

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In this article, a highly efficient power module is presented with two class-E power amplifiers and an adaptive power combiner for transmitting output powers >100 W at 6.78 MHz in a wireless power transfer system. The losses caused by the combiners and interstage matching circuits or mismatching between the amplifier, and the combiners can significantly reduce the overall efficiency of the power module. To achieve an efficient combination of the output amplifier signals, the adaptive power combiner is proposed based on the consideration of the optimum load impedance characteristics of the power amplifiers. The input impedance of the combiner is designed using series capacitors and resistors between the two input ports of the combiner and the two output signals of the class-E amplifiers at the optimum load condition. The output performances of the proposed module can decrease based on the component mismatch between the two power amplifiers. The proposed power module was implemented on an FR4 PCB, with a 15 mm metal heat sink, and demonstrated an output power of 123.3 W, a power-added efficiency of 85.7%, and a power gain of 25.6 dB at 6.78 MHz. The second harmonic suppression of the module was 37 dBc.

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Choi, Hojong. "Development of a Class-C Power Amplifier with Diode Expander Architecture for Point-of-Care Ultrasound Systems". Micromachines 10, n.º 10 (14 de outubro de 2019): 697. http://dx.doi.org/10.3390/mi10100697.

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Point-of-care ultrasound systems are widely used in ambulances and emergency rooms. However, the excessive heat generated from ultrasound transmitters has an impact on the implementation of piezoelectric transducer elements and on battery consumption, thereby affecting the system’s sensitivity and resolution. Non-linear power amplifiers, such as class-C amplifiers, could substitute linear power amplifiers, such as class-A amplifiers, which are currently used in point-of-care ultrasound systems. However, class-C power amplifiers generate less output power, resulting in a reduction of system sensitivity. To overcome this issue, we propose a new diode expander architecture dedicated to power amplifiers to reduce the effects of sinusoidal pulses toward the power supply. Thus, the proposed architecture could increase the input pulse amplitudes applied to the main transistors in the power amplifiers, hence increasing the output voltage of such amplifiers. To verify the proposed concept, pulse-echo responses from an ultrasonic transducer were tested with the developed class-C power amplifier using a resistor divider and the designed diode expander architecture. The peak-to-peak amplitude of the echo signals of the ultrasonic transducers when using a class-C power amplifier with a diode expander architecture (2.98 Vp–p) was higher than that for the class-C power amplifier with a resistor divider architecture (2.51 Vp–p). Therefore, the proposed class-C power amplifier with diode expander architecture is a potential candidate for improving the sensitivity performance of piezoelectric transducers for point-of-care ultrasound systems.

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Ismail, Khadijah, P. S. Menon, Sahbudin Shaari, Abang Annuar Ehsan, Norhana Arsad e A. Ashrif A. Bakar. "Link Power Level Improvements in an Amplified 8-Channel CWDM System with Hybrid EDFA-SOA Pre-Amplifier". Applied Mechanics and Materials 799-800 (outubro de 2015): 1361–65. http://dx.doi.org/10.4028/www.scientific.net/amm.799-800.1361.

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The link power improvement in a coarse wavelength division multiplexing (CWDM) system which is transmitted using a hybrid erbium-doped fiber amplifier (EDFA) and semiconductor optical amplifier (SOA) scheme as a pre-amplifier, is discussed. The network is designed for amplifying 8 CWDM channels ranging from 1471 nm to 1611 nm. The hybrid amplifiers’ gain measurement is obtained from experimental work with gain peak at 22 dB which is observed at 1531 nm. The amplifiers also caused power increment of 5.06 dB in the transmission link before the signal is split individually at the receiving end. Based on the higher gain peaks and power spectrum at 1531 nm and 1551 nm wavelengths, the proposed amplified link would be useful for the transmission of video applications.

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Kumar, Sunil, e Arun Kr Chatterjee. "Comparative study of different Sense Amplifiers in 0.18um technology". INTERNATIONAL JOURNAL OF COMPUTERS & TECHNOLOGY 7, n.º 3 (10 de junho de 2013): 615–19. http://dx.doi.org/10.24297/ijct.v7i3.3440.

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A comparative study of different types of sense amplifiers [1] using 0.18um technology is presented. The sense amplifiers under considerations are used in SRAM and DRAM cells.The sensing delay of different types of sense amplifiersÂ are evaluated with respect to variation of bitline capacitance. Comparative results are also provided for the variation in delay with respect to power supply. Extensive results based on 0.18um CMOS technology using CADENCE Spectre simulation tools are presented for different architectures of sense amplifiers. From these results it has been proven that if the output of sense amplifier is isolated from the bitline parasitic capacitance then the sensing delay of sense amplifier reduces.

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Alybin, Vyacheslav, Aleksey Syomochkin, Vladimir Rozhkov e Sergey Avramenko. "Major Items of Construction Amplifiers of UNF Power for the Auxiliary Systems of Spacecrafts". Infocommunications and Radio Technologies 5, n.º 1 (25 de março de 2022): 70–78. http://dx.doi.org/10.29039/2587-9936.2022.05.1.05.

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Prospective designs of microwave power amplifiers for on-board equipment of service systems are considered, in which the problem of minimizing the area occupied by them on a thermally stabilized plate of a spacecraft is solved. Microwave power amplifiers provide good heat dissipation and require a degree of redundancy. Each of the amplifiers included in the redundant microwave power amplifier is made on boards located perpendicular to the heat-stabilized plate and fixed on the plate on one or both sides. The area occupied by a duplicated or triple redundant microwave power amplifier does not exceed the area on a thermally stabilized plate required to remove heat from one microwave power amplifier included in its composition. And for a triple redundant microwave power amplifier – the area required for heat removal from two such amplifiers.

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9

Mbonane, Sandile H., e Viranjay M. Srivastava. "Comparative Parametric Analysis of Class-B Power Amplifier Using BJT, Single-Gate MOSFET, and Double-Gate MOSFET". Materials Science Forum 1053 (17 de fevereiro de 2022): 137–42. http://dx.doi.org/10.4028/p-57edxh.

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This paper presents system performance indices for a class-B power amplifier using Double-Gate (DG) Metal Oxide Semiconductor Field Effect Transistor (MOSFET). It also presents a comparative analysis of three power amplifiers using different switching devices, i.e. Bipolar Junction Transistor (BJT), MOSFET, and DG MOSFET. The MOSFET used in this research work is based on Silicon for n-MOSFET and SiO2 has been used as oxide layer. These power amplifiers are also being designed and simulated to test the speed and time (taken for each of these power amplifiers) to get the output signal when an input signal is applied. A comparison of these three power amplifier circuits is taken in the tabular form to conclude which power amplifier circuit performs better regarding its switching speed and the time. Switching speed relates with the time taken to amplify the signal, which is the same as its time to amplify the signal to a specific gain. Settling time for these three types of power amplifiers have also been tested and presented for the performance of these power amplifiers.

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Murtianta, Budihardja, e Erlina Sari. "Penguat Jembatan dengan Untai Pembalik Fase". Elektrika 14, n.º 2 (22 de outubro de 2022): 58. http://dx.doi.org/10.26623/elektrika.v14i2.5329.

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The maximum output voltage of the audio amplifier is limited to the magnitude of the power supply voltage of the power transistor or the operational amplifier on the final amplifier. This limits the maximum power of the audio amplifier output. The way to enlarge the output power of the audio amplifier without increasing the voltage is the bridge method or bridged modes. With this method a bridge amplifier will be generated. This Bridge Amplifier is also known as Bridge-Tied Load (BTL) or Bridged Transformerless. The principle of Bridge Amplifiers is to use a pair of final amplifiers whose outputs have opposite phase each other. There are 3 ways to make a pair of power amplifiers have opposing phases: with internal modification, with an audio transformer (phase splitting audio input transformer) and with a simple active phase reversal splitter circuit). This paper will discuss Bridge Amplifiers with simple phase inverting circuits. A pair of audio power amplifiers using two TDA2050 chips which are operated at ± 19 Volt supply voltage. The phase inverting circuit using IC TL072. Sinusoidal signal with an amplitude of 200 mVp and a frequency of 1 KHz is used as an input signal. The results to be observed and measured are gain, input, output and bandwidth of the bridged amplifier compared to the usual amplifier

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Xu, Lisong, Hongwen Li, Pengzhi Li e Chuan Ge. "The Application of Classical Control in the Design and Analysis of Power Amplifiers for Driving Piezoelectric Stack Actuators". Electronics 10, n.º 6 (18 de março de 2021): 720. http://dx.doi.org/10.3390/electronics10060720.

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This study proposes a new method to design an analog circuit based on the control model of the circuit, and the method is applied in the design of the power amplifiers for driving piezoelectric stack actuators. Focusing on the stability of the circuit, two power amplifiers for driving piezoelectric stack actuators are analyzed deeply. The power amplifier using high-voltage operational amplifiers has a simple circuit structure, and the bandwidth and the ripple of the power amplifier are about 43 kHz and 16 mV, respectively. As for the power amplifier using general operational amplifiers, it possesses the qualities of low cost and simple circuit structure, and the bandwidth and the ripple are 53 kHz and less than 2 mV, respectively. Moreover, the proposed power amplifiers can well drive the mechanism stage during the moving range of the piezoelectric stack actuator, and the travelling ranges are both about 13 μm. Viewing the circuit design as control system design, applying control system design method in circuit design and working with PSpice simulation of the circuit: these are the main contents of the proposed method, and the method offers an answer to designing a power amplifier systematically.

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12

Choi, Hojong. "Power Amplifier Design for Ultrasound Applications". Micromachines 14, n.º 7 (30 de junho de 2023): 1342. http://dx.doi.org/10.3390/mi14071342.

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A design analysis of the power amplifiers developed for ultrasound applications was conducted because ultrasound applications require different types of power amplifiers, which are one of the most critical electronic components in ultrasound systems. To generate acoustic signals using transducers, which are among the most important mechanical devices in ultrasound systems, an appropriate output voltage, current, or power signal must be produced by a power amplifier. Therefore, an appropriate design analysis of the power amplifier must be conducted to obtain the optimal performance from a transducer. In addition, because of new ultrasound research trends, such as ultrasound systems with other imaging modalities and wireless ultrasound systems, the selection of an appropriate power amplifier could improve the performance of an ultrasound system with other imaging and therapy modalities. This paper describes the design parameters of a power amplifier, including the gain, bandwidth, harmonic distortion, and efficiency. Each power amplifier has specific applications and limitations. Therefore, this review will assist design engineers and ultrasound researchers who need to develop or use power amplifiers in ultrasound applications.

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Park, Min-Sang, Gwon-Seok Sun e Jin-Young Kim. "A Study on the Automatic Calibration Function of RF Amplifiers Using Artificial Neural Networks". Korea Industrial Technology Convergence Society 28, n.º 2 (30 de junho de 2023): 41–49. http://dx.doi.org/10.29279/jitr.2023.28.2.41.

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In this study, power amplifiers are designed and manufactured based on the frequency specifications by customers. After learning appropriate compensation values according to the function and performance degradation factors of the manufactured power amplifier using an artificial neural network, the power amplifier itself can maintain an optimal performance when its function and performance degrade. The artificial neural networks are applied to power amplifiers using the STM32F series of microcontrollers, which are being widely used for industrial purposes in recent years. Hence, after manufacturing the power amplifiers, the optimal state is maintained without additional tuning by workers, as well as changes in the external environment and aging of electronics parts. When the performance of the power amplifier is degraded owing to other factors, the performance of the power amplifier can be improved by itself.

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Tiwari, Nitendra kumar. "Low Power Reduction Techniques Implementation and Analysis in Sense Amplifier Circuit Configurations". Journal of Futuristic Sciences and Applications 5, n.º 2 (2022): 31–37. http://dx.doi.org/10.51976/jfsa.522205.

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MTCMOS (Multi-Threshold CMOS), sleepy stack, sleepy keeper, and footer stack are examples of low power saving techniques incorporated into the core gpdk 90nm technology papers used in the proposed study using Cadence. The main focus of these tests is the power consumption of various sense amplifier circuits. The simulation results show that the charge-transfer sense amplifier uses much less energy than voltage and current sense amplifiers. The present mode detecting amplifier’s power consumption can be decreased by up to 98 percent by using MTCMOS technology.

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Yan, Jonmei J., Paul Draxler, Calogero D. Presti, Donald F. Kimball e Peter M. Asbeck. "Digital predistortion of envelope-tracking power amplifiers under average power back-off and long-term average power efficiency for base-station applications". International Journal of Microwave and Wireless Technologies 5, n.º 2 (18 de fevereiro de 2013): 171–77. http://dx.doi.org/10.1017/s1759078713000147.

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In many base-station applications, the load/usage fluctuates over time periods of hours to days, thereby varying the required transmit power by as much as 10 dB. It is desirable to maintain high efficiency and linearity in the power amplifier under these back-off conditions in order to achieve high long-term efficiency. This paper demonstrates a scalable digital predistortion (DPD) approach that can be applied under different power back-off levels in envelope-tracking (ET) amplifiers and quantifies the associated efficiency. Efficiency comparisons are made with other amplifier configurations such as Class B and Doherty. Efficiency of 60% at full power (35 W average power) and >30% efficiency at 10 dB average power back-off are measured in an ET amplifier with a 7.54 dB peak-to-average ratio (PAPR) single-carrier WCDMA signal while meeting linearity specifications. Long-term base-station usage probability functions are presented. The long-term efficiency of the ET amplifiers is simulated to be greater than that of Class B and Doherty amplifiers.

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SUDO, SHOICHI. "PROGRESS IN OPTICAL FIBER AMPLIFIERS". International Journal of High Speed Electronics and Systems 07, n.º 01 (março de 1996): 1–35. http://dx.doi.org/10.1142/s0129156496000025.

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Recent progress in fiber amplifier technology is reviewed. Broad band and high power are currently the key goals in the field of fiber amplifiers in conjunction with amplified system development. Broad-band EDFAs using fluoride-based hosts and high-power EDFAs with powerful pump lasers are described in detail. Recent progress and other requirements for optical amplifiers i.e. high gain, low noise, and high reliability, are all reviewed. The limitations in relation to achievable gain are described as well as the highest gain ever achieved. A method for its reduction are described. In relation to reliability, this paper mainly focuses on fluoride fiber. Recent progress on the main characteristics of 1.3 µm PDFA is reviewed and transmission experiment are described. Several attempts to construct fiber amplifiers operating at 0.8 µm, 1.4 µm, and 1.65 µm are also reviewed. In the field of amplified systems, WDM and remote pumping TDM techniques are a high priority. In particular, various WDM experiments such as long-distance WDM transmission, WDM soliton transmission, and WDM networks are all described in detail.

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Zhou, Yiping, Xudong Li, Chaojie Wei, Xiaojie Chen, Haobo Xu, Rongwei Fan, Deying Chen, Yugang Jiang e Renpeng Yan. "5 kHz, 4.2mJ, 900 ps end-pumped Nd:YVO₄ MOPA laser system". Optics Express 30, n.º 16 (29 de julho de 2022): 29833. http://dx.doi.org/10.1364/oe.468386.

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A 5 kHz sub-nanosecond master oscillator power amplifier (MOPA) laser system was reported in this paper. The master oscillator was an electro-optically Q-switched Nd:YVO4 laser directly pumped at 879 nm, yielding a pulse energy of 520 µJ and a pulse width of 900 ps at 5 kHz. With two Nd:YVO4 amplifiers directly pumped at 914 nm, the pulse energy was further scaled up. Under the absorbed pump energy of 11.0 mJ, the pulse energy was amplified to 4.2 mJ, corresponding to a peak power of 4.7 MW. The optical-to-optical efficiency of the amplifiers reached 33.5%.

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Chiou, Hwann-Kaeo, Hsin-Chieh Lin e Da-Chiang Chang. "High-Efficiency and Cost-Effective 10 W Broadband Continuous Class-J Mode Quasi-MMIC Power Amplifier Design Utilizing 0.25 μm GaN/SiC and GaAs IPD Technology for 5G NR n77 and n78 Bands". Electronics 12, n.º 16 (17 de agosto de 2023): 3494. http://dx.doi.org/10.3390/electronics12163494.

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This paper presents two power amplifiers designed for 5G NR n77 and n78 bands. These power amplifiers were fabricated using WINTM Semiconductors’ 0.25 μm GaN/SiC technology and GaAs IPD technology. To achieve a reduction in costs, GaAs IPD technology was incorporated in the design, leading to the realization of a quasi-monolithic microwave integrated circuit design. To ensure high power, high efficiency, and broadband operation, a continuous Class-J mode output matching network was utilized. The power amplifier with split chip-on-board wire-bond assembly had a power gain of 21.7 dB, a 3 dB power bandwidth ranging from 2.85 GHz to 4.48 GHz, a saturation power of 40.3 dBm, and a peak power-added efficiency of 39.5%. On the other hand, the power amplifier with stack chip-on-board wire-bond assembly had a power gain of 21.7 dB, a 3 dB power bandwidth ranging from 2.84 GHz to 4.47 GHz, a saturation power of 40 dBm, and a peak power-added efficiency of 36.5%. For a 5G NR FR1 256-QAM 100-MHz bandwidth modulated signal with a frequency range of 3.3 GHz to 4.2 GHz, both the split and stack chip-on-board wire-bond assembly power amplifiers achieved average output powers of 29.6 dBm and 28.3 dBm, respectively. These output powers were measured under an error vector magnitude requirement of 3.5%.

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You, Kiheum, e Hojong Choi. "Wide Bandwidth Class-S Power Amplifiers for Ultrasonic Devices". Sensors 20, n.º 1 (4 de janeiro de 2020): 290. http://dx.doi.org/10.3390/s20010290.

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Wide bandwidth ultrasonic devices are a necessity in high-resolution ultrasonic systems. Therefore, constant output voltages need to be produced across the wide bandwidths of a power amplifier. We present the first design of a wide bandwidth class-S power amplifier for ultrasonic devices. The −6 dB bandwidth of the developed class-S power amplifier was measured at 125.07% at 20 MHz, thus, offering a wide bandwidth for ultrasonic devices. Pulse-echo measurement is a performance measurement method used to evaluate the performance of ultrasonic transducers, components, or systems. The pulse-echo signals were obtained using an ultrasonic transducer with designed power amplifiers. In the pulse-echo measurements, time and frequency analyses were conducted to evaluate the bandwidth flatness of the power amplifiers. The frequency range of the ultrasonic transducer was measured and compared when using the developed class-S and commercial class-A power amplifiers with the same output voltages. The class-S power amplifiers had a relatively flat bandwidth (109.7 mV at 17 MHz, 112.0 mV at 20 MHz, and 109.5 mV at 23 MHz). When the commercial class-A power amplifier was evaluated under the same conditions, an uneven bandwidth was recorded (110.6 mV at 17 MHz, 111.5 mV at 20 MHz, and 85.0 mV at 23 MHz). Thus, we demonstrated that the designed class-S power amplifiers could prove useful for ultrasonic devices with a wide frequency range.

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Dong, Ruibing, Yiheng Song e Yang Xing. "A 110 GHz Feedback Amplifier Design Based on Quasi-Linear Analysis". Electronics 12, n.º 17 (4 de setembro de 2023): 3725. http://dx.doi.org/10.3390/electronics12173725.

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The power gain and output power of millimeter-wave (mm-Wave) and terahertz (THz) amplifiers are critical performance metrics, particularly when the operating frequencies of amplifiers are near to the maximum oscillator frequency (fmax) of the transistor. This paper presents the design of a 110 GHz amplifier based on the quasi-linear method. The power gain can be boosted to maximum achievable gain (Gmax) using a linear, lossless, reciprocal feedback network, though this leads to a simultaneous decrease in output power. Based on quasi-linear analysis, for an amplifier with Gmax gain, when the K-factor is equal to 1, the output power is zero. To avoid the very low output power of amplifiers, a new approach is proposed to balance power gain and output power. A 110 GHz six-stage feedback amplifier was designed using the proposed approach and fabricated using 40 nm CMOS technology. The measured power gain is 26.5 dB, and the saturation output power is 13 dBm at 110 GHz.

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Sajedin, Maryam, I. T. E. Elfergani, Jonathan Rodriguez, Raed Abd-Alhameed e Monica Fernandez Barciela. "A Survey on RF and Microwave Doherty Power Amplifier for Mobile Handset Applications". Electronics 8, n.º 6 (25 de junho de 2019): 717. http://dx.doi.org/10.3390/electronics8060717.

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This survey addresses the cutting-edge load modulation microwave and radio frequency power amplifiers for next-generation wireless communication standards. The basic operational principle of the Doherty amplifier and its defective behavior that has been originated by transistor characteristics will be presented. Moreover, advance design architectures for enhancing the Doherty power amplifier’s performance in terms of higher efficiency and wider bandwidth characteristics, as well as the compact design techniques of Doherty amplifier that meets the requirements of legacy 5G handset applications, will be discussed.

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Jurnal, Redaksi Tim. "PERANCANGAN RANGKAIAN PENGUAT DAYA DENGAN TRANSISTOR". Sutet 7, n.º 2 (27 de novembro de 2018): 88–92. http://dx.doi.org/10.33322/sutet.v7i2.81.

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The power amplifier circuit is a circuit used to amplify or magnify input signals. The use of a transistor as an amplifier is that the current on the base is used to control the larger current given to the collector through the transistor. The small current change on the controlling base is what is called a large change in the current flowing from the collector to the emitter. The advantages of the amplifier transistors can not only amplify the signal, but these transistors can also be used as current amplifiers, voltage amplifiers and power amplifiers.

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Choi, Hojong. "Prelinearized Class-B Power Amplifier for Piezoelectric Transducers and Portable Ultrasound Systems". Sensors 19, n.º 2 (12 de janeiro de 2019): 287. http://dx.doi.org/10.3390/s19020287.

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Portable ultrasound systems typically suffer from unwanted heat and limited battery life, resulting in reduced system performance or the applicable number of piezoelectric transducer elements. This can be a bottleneck in widely used portable ultrasound systems. Class-A power amplifiers are typically used in portable ultrasound systems. However, unwanted heat dissipation needs to be reduced by using large cooling fans and heat pipe structures. To reduce unwanted heat, class-B power amplifiers may be a possible solution. However, the non-linearity of class-B power amplifiers could limit their integration with piezoelectric transducers because non-linearity in the high-voltage output of the power amplifiers deteriorates the sensitivity of portable ultrasound systems. To improve the linearity of the power amplifier, we developed prelinearized class-B power amplifiers for piezoelectric transducers and portable ultrasound systems. To verify our proposed method, we compared the performances of class-B and prelinearized class-B power amplifiers in their pulse-echo responses. Therefore, prelinearized class-B power amplifiers are a possible solution to produce better echo signal performance in piezoelectric transducers and portable ultrasound systems.

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Ivanyushkin, Roman Yu, e Kirill O. Razin. "ENERGY EFFICIENCY OF THE POWER AMPLIFIER ACCORDING TO W. DOHERTY’S SCHEME WITH AUTOMATIC POWER ADJUSTMENT". SYNCHROINFO JOURNAL 9, n.º 1 (2023): 25–29. http://dx.doi.org/10.36724/2664-066x-2023-9-1-25-29.

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At present, in relation to the power amplifiers of digital television broadcast transmitters, the scheme proposed by engineer William Dougherty for the construction of broadcast transmitters with amplitude modulation is widely used. W. Dougherty’s method, today is practically the only solution for improving the energy efficiency of OFDM signal power amplifiers, as applied to terrestrial digital television transmitters, when the wide band of the envelope of such a signal does not allow the construction of a transmitter based on a polar architecture. Transmitters for digital terrestrial television broadcasting using linear power amplifiers built on the basis of the W. Doherty method are developed and produced. When building transmitters for terrestrial digital television broadcasting, the problem of ensuring an acceptable efficiency of a linear power amplifier is very acute. The main reason for the low efficiency of such amplifiers is the high OFDM crest factor of the digital television radio signal. The problem of increasing the linear power amplifiers average efficiency of digital broadcasting transmitters is considered. The joint application of two methods for constructing high-efficiency linear power amplifiers is discussed: the method of William Dougherty and method of automatic power mode control. Preliminary assessment results of the energy gain from the combined use of these two methods, obtained by computer circuit simulation, are presented.

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Andrews, John R. "Interferometric power amplifiers". Optics Letters 14, n.º 1 (1 de janeiro de 1989): 33. http://dx.doi.org/10.1364/ol.14.000033.

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Kwak, Joon Young, e Sung-Yun Park. "Compact Continuous Time Common-Mode Feedback Circuit for Low-Power, Area-Constrained Neural Recording Amplifiers". Electronics 10, n.º 2 (11 de janeiro de 2021): 145. http://dx.doi.org/10.3390/electronics10020145.

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A continuous-time common-mode feedback (CMFB) circuit for low-power, area-constrained neural recording amplifiers is proposed. The proposed CMFB circuit is compact; it can be realized by simply replacing passive components with transistors in a low-noise folded cascode operational transconductance amplifier (FC-OTA) that is one of the most widely adopted OTAs for neural recording amplifiers. The proposed CMFB also consumes no additional power, i.e., no separate CMFB amplifier is required, thus, it fits well to low-power, area-constrained multichannel neural recording amplifiers. The proposed CMFB is analyzed in the implementation of a fully differential AC-coupled neural recording amplifier and compared with that of an identical neural recording amplifier using a conventional differential difference amplifier-based CMFB in 0.18 μm CMOS technology post-layout simulations. The AC-coupled neural recording amplifier with the proposed CMFB occupies ~37% less area and consumes ~11% smaller power, providing 2.67× larger output common mode (CM) range without CM bandwidth sacrifice in the comparison.

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Kwak, Joon Young, e Sung-Yun Park. "Compact Continuous Time Common-Mode Feedback Circuit for Low-Power, Area-Constrained Neural Recording Amplifiers". Electronics 10, n.º 2 (11 de janeiro de 2021): 145. http://dx.doi.org/10.3390/electronics10020145.

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A continuous-time common-mode feedback (CMFB) circuit for low-power, area-constrained neural recording amplifiers is proposed. The proposed CMFB circuit is compact; it can be realized by simply replacing passive components with transistors in a low-noise folded cascode operational transconductance amplifier (FC-OTA) that is one of the most widely adopted OTAs for neural recording amplifiers. The proposed CMFB also consumes no additional power, i.e., no separate CMFB amplifier is required, thus, it fits well to low-power, area-constrained multichannel neural recording amplifiers. The proposed CMFB is analyzed in the implementation of a fully differential AC-coupled neural recording amplifier and compared with that of an identical neural recording amplifier using a conventional differential difference amplifier-based CMFB in 0.18 μm CMOS technology post-layout simulations. The AC-coupled neural recording amplifier with the proposed CMFB occupies ~37% less area and consumes ~11% smaller power, providing 2.67× larger output common mode (CM) range without CM bandwidth sacrifice in the comparison.

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Farmer, Thomas J., Ali Darwish, Benjamin Huebschman, Edward Viveiros e Mona E. Zaghloul. "High power density SiGe millimeter-wave power amplifiers". International Journal of Microwave and Wireless Technologies 3, n.º 6 (1 de julho de 2011): 615–20. http://dx.doi.org/10.1017/s1759078711000638.

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This paper presents measured results for two-stage and three-stage high-voltage/high-power (HiVP) amplifiers implemented in a commercial 0.12 μm silicon germanium (SiGe) heterojunction bipolar transistor (HBT) bipolar Complementary Metal Oxide Semiconductor (BiCMOS) process at millimeter wave. The HiVP configuration provides a new tool for millimeter-wave silicon designers to achieve large output voltage swings, high output power density, customizable bias, and a way to minimize, if not eliminate, matching circuitry at millimeter-wave frequencies. The two-stage amplifier has achieved a PSAT = 5.41 dBm with a power added efficiency (PAE) of 8.06% at center frequency 30 GHz. The three-stage amplifier has achieved a PSAT = 8.85 dBm with a PAE of 11.35% with a total chip area of 0.068 mm2 at center frequency 30 GHz. Simulation, layout, fabrication, and measurement results are presented in this paper.

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Nadir, Z., e F. Touati. "Class-E Amplifier Design Improvements for GSM Frequencies". Journal of Engineering Research [TJER] 7, n.º 2 (1 de junho de 2011): 74. http://dx.doi.org/10.24200/tjer.vol8iss1pp74-82.

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Efficient power amplifiers are essential in portable battery-operated systems such as mobile phones. Also, the power amplifier (PA) is the most power-consuming building block in the transmitter of a portable system. This paper investigates how the efficiency of the power amplifier (which is beneficial for multiple applications in communcation sector) can be improved by increasing the efficiency of switching mode class E power amplifiers for frequencies of 900 MHz and 1800 MHz. The paper tackles modeling, design improvements and verification through simulation for higher efficiencies. This is the continuation of previous work by the authors. These nonlinear power amplifiers can only amplify constant-envelope RF signals without introducing significant distortion. Mobile systems such as Advanced Mobile Phone System (AMPS) and Global System for Mobile communications (GSM) use modulation schemes which generate constant amplitude RF outputs in order to use efficient but nonlinear power amplifiers. Improvements in designs are suggested and higher efficiencies are achieved, to the tune of 67.1% (for 900 MHz) and 67.0% (1800 MHz).

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Mabrok, Mussa, Zahriladha Zakaria e Nasrullah Saifullah. "Design of Wide-band Power Amplifier based on Power Combiner Technique with Low Intermodulation Distortion". International Journal of Electrical and Computer Engineering (IJECE) 8, n.º 5 (1 de outubro de 2018): 3504. http://dx.doi.org/10.11591/ijece.v8i5.pp3504-3511.

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RF power amplifiers are one of challenging blocks in designing radio frequency transceivers, this is due to non-linearity behavior of power amplifiers that leads to inter-modulation distortion. This paper presents the design of wide-band power amplifier which combined with parallel coupled line band pass filter at the input and output of power amplifier to allow the only required frequency band to pass through the power amplifier. Class-A topology and ATF-511P8 transistor are used in this design. Advanced Design System software used as a simulation tool to simulate the designed wide-band power amplifier. The simulation results showed an input return loss (S11) which less than -10dB, and gain (S21) is higher than 10 dB over the entire frequency band and considers as flat as well. The designed amplifier is stable over the bandwidth (K>1). Inter-modulation distortion is -56.919dBc which is less than -50dBc with 10dBm input power. The designed amplifier can be used for the microwave applications which include weather radar, satellite communication, wireless networking, mobile, and TV.

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Jang, Jejin, Jaehyuk Choi, Donghun Lee e Hyungsoo Mok. "Design Procedure of Cascaded Multilevel Inverter for High-Power Amplifier in SONAR System". Energies 17, n.º 7 (26 de março de 2024): 1581. http://dx.doi.org/10.3390/en17071581.

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In recent years, there has been a trend toward expanding the operating frequency range and increasing the output power of Sound Navigation and Ranging (SONAR) systems to enhance their acoustic detection capabilities. However, due to this increase in operational power, the electrical capacity of amplifiers for SONAR system operation also increases, necessitating High-Power Amplifiers. When configured with a single amplifier, as in conventional methods, the volume of amplifiers increases due to volumetric increases in heat dissipation, components, and windings. These issues are detrimental to SONAR amplifier installation, mobility, maintenance, and equipment lifespan due to stress on individual components. Additionally, amplifiers for SONAR systems are comprised of power conversion devices, transformers for LC filters and matching, necessitating consideration of LC filters and matching transformers for enhancing voltage quality and efficiency to improve amplifier performance transmitted to SONAR transducers. However, previous research has focused on single-amplifier design methods, neglecting such considerations. Therefore, this paper proposes a design technique that overcomes the drawbacks of using the conventional design method by configuring multiple H-bridge inverters in a cascade format and utilizes one of the optimization algorithms, Particle Swarm Optimization (PSO), to derive amplifier design techniques that optimize component parameters for enhancing high-capacity amplifier performance. Subsequently, theoretical analysis, simulations, and experimental results comparing the proposed high-power amplifier design method with conventional single-amplifier design methods demonstrate similar error rates in operational frequency bands.

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Oki, Daiki, Satoru Kawauchi, Cong Bing Li, Masataka Kamiyama, Seiichi Banba, Toru Dan, Nobuo Takahashi e Haruo Kobayashi. "A Power-Efficient Noise Canceling Technique Using Signal-Suppression Feed-Forward for Wideband LNAs". Key Engineering Materials 643 (maio de 2015): 109–16. http://dx.doi.org/10.4028/www.scientific.net/kem.643.109.

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This paper presents a power-efficient noise-canceling technique based on the feed-forward amplifiers, considering a fundamental tradeoff between noise figure (NF) and power consumption in the design of wide-band amplifiers. By suppressing the input signal of the noise cancellation amplifier, the nonlinear effect on the amplifier can be reduced, as well as the power consumption can be smaller. Furthermore, as a lower gain of the noise-canceling sub-amplifier can be achieved simultaneously, further reduction of the power consumption becomes possible. The verification of the proposed technique is conducted with Spectre simulation using 90nm CMOS process.

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Hasegawa, Naoki, e Naoki Shinohara. "Sidelobe reduction with a GaN active array antenna". Wireless Power Transfer 4, n.º 2 (setembro de 2017): 113–19. http://dx.doi.org/10.1017/wpt.2017.8.

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This work proposes a tunable sidelobe reduction method based on a GaN active-antenna technique, in which the output radio frequency power is controlled by the DC drain voltage of the amplifiers. In this study, a 1 × 4 array of active antenna with GaN amplifiers is designed and fabricated. GaN amplifiers capable of up to 10 W-class power output are fabricated and arranged for a four-way active-array antenna. The fabricated single-stage GaN amplifier offers a maximum power-added efficiency of 59.6% and a maximum output power of 39.3 dBm. The maximum output power is decreased to 36.5 dBm upon decreasing the operating drain voltage from 55 to 35 V. In this study, a 4.5 dB sidelobe reduction is demonstrated in a 1 × 4 active antenna based on this output power difference for each amplifier.

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Muhamed, Mais, Fariz Abboud e Mohamad Alhariri. "Broadband Performance of a 6W Pushpull Power Amplifier on the VHF-UHF Band". International Journal of Electronics, Communications, and Measurement Engineering 11, n.º 1 (janeiro de 2022): 1–8. http://dx.doi.org/10.4018/ijecme.294892.

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In this paper, a broadband 100-700 MHz power amplifier was designed. The results of simulation are compared with the measurements,The shunt feedback of power amplifier module provides the linear and broadband frequency amplification. The push-pull topology with ferrite balun provides enhanced efficiency and high power generation along In this work a commercially available LDMOS transistor (D2003UK) is used, The amplifier can deliver 6W to a 50 ohm load and has 14dB gain.Broadband high power amplifiers are considered as key components in next generation software defined radio communication systems. In principle, application of a linear, highly efficient wide band amplifier can replace several narrow band power amplifiers, yielding reduced costs and form factor, This paper uses D2003UK a transistor to achieve a 6 Watt amplifier for broad band .

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Lee, Dongho. "Second Harmonic Frequency Adjustment Strategy for Class-E Amplifier Design". International Journal of Electrical and Electronics Research 11, n.º 3 (10 de julho de 2023): 658–61. http://dx.doi.org/10.37391/ijeer.110303.

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Class-E amplifiers are a type of switching amplifiers with an efficiency that approaches 100%. The harmonic frequency is very important in the design of Class-E amplifiers. In this study, the second harmonic frequency is considered in the design of a Class-E amplifier. The Class-E amplifier has been fabricated on FR4 and has demonstrated a power-added efficiency (PAE) of 74.5% at 1.01 GHz. This result shows that the termination of the second-harmonic output is essential for switching amplifiers.

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Sombrin, Jacques B. "Optimization criteria for power amplifiers". International Journal of Microwave and Wireless Technologies 3, n.º 1 (fevereiro de 2011): 35–45. http://dx.doi.org/10.1017/s1759078710000863.

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This paper describes existing and new criteria for comparison and optimization of non-linear power amplifiers such as RF or microwave transmitters. In addition to intermodulation, receiver noise, and losses in the transmission system, the proposed new criteria take into account efficiency or consumed power. This results in the global optimization of a combined signal-to-noise-plus-intermodulation ratio as a function of saturated or nominal power but also consumed or dissipated power. Saturated power is limited by available technology. Consumed power and dissipated power are some of the main constraints in telecommunication satellite payloads, mobile phone handsets, and RFID (Radio Frequency IDentification). Another constraint comes from the limited size of antennas, which limits the system equivalent isotropic radiated power and gain-to-temperature ratio. With the proposed criteria the designer will be able to compare different amplifier technologies and to optimize the design and operating point of each stage of a multistage amplifier or a linearizer for a given amplifier. Interference from same or other systems is also introduced in the optimization through the use of signal-to-noise-plus-IM-plus-interference ratio criteria.

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Guan, Biao, Fengping Yan, Wenguo Han, Qi Qin, Dandan Yang, Ting Li, Chenhao Yu, Xiangdong Wang, Kazuo Kumamoto e Yuping Suo. "High-Power, Narrow-Linewidth, Continuous-Wave, Thulium-Doped Fiber Laser Based on MOPA". Photonics 10, n.º 4 (23 de março de 2023): 347. http://dx.doi.org/10.3390/photonics10040347.

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A high-power, narrow-linewidth, continuous-wave, thulium-doped fiber laser (TDFL) based on a master-oscillator power-amplifier (MOPA) was experimentally demonstrated. The main oscillator (seed source) yielded 0.64 W of narrow-linewidth laser output at a central wavelength of 1940.32 nm and a 3 dB spectral bandwidth of 0.05 nm. The output narrow-linewidth laser from the main oscillator was amplified by two-stage, cladding-pumped, thulium-doped, all-fiber amplifiers. The main amplifier yielded 26 W of narrow-linewidth laser at a central wavelength of 1940.33 nm. The slope efficiency of the main amplifier was approximately 55.6%. Significant residual pumping light component in the output laser was not observed. During the amplification process, no stimulated Brillouin scattering (SBS) effect, strong amplified spontaneous emission (ASE) effect, and parasitic lasers were observed at the reverse monitoring end. Moreover, the output power was only limited by the incident pump power and the output power had a good stability in a 50 min monitoring period.

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K. Abass, A. "Optical Fiber Amplifiers: Optimization and PerformanceEvaluation". DJES 12, n.º 1 (1 de março de 2019): 66–72. http://dx.doi.org/10.24237/djes.2019.12108.

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This work demonstrates the simulation of two different types of optical fiber amplifiers (OFA) utilizing OptiSystem–10, namely, 3 m length of erbium doped fiber amplifier (EDFA) and 7 km length of Raman fiber amplifier (RFA). The counter-pumped architecture is adopted for both proposed optical amplifiers. The optimum pump power (OPP) for each amplifier determines in which the longest 3–dB flat gain bandwidth (3–dB BW), reasonable average gain level (Gav), proper average noise figure (NFav) and lower gain variation (Gvar) were achieved. The EDFA shows best performance at conventional band (C–band) within the pump power of 30 mW.While the better performance is observed at long band (L–band) within the pump power of 600 mW for the RFA.

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Akinin, V. E., O. V. Borisov, K. A. Ivanov, Yu V. Kolkovskiy, V. M. Minnebaev e Al V. Redka. "AIR-COOLED 350 W X-BAND SOLID-STATE POWER AMPLIFIER". Electronic engineering Series 2 Semiconductor devices 258, n.º 3 (2020): 43–52. http://dx.doi.org/10.36845/2073-8250-2020-258-3-43-52.

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In this paper we present the results of the design and production of an air-cooled X-band solid-state power amplifier based on AlGaN/GaN/SiC Schottky FET. The power amplifier includes: preliminary power amplifier, output power amplifiers, set of secondary power supplies, digital control unit, monitoring system for the power amplifier performance, set of microwave power waveguide combiners.

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Fan, Luwei, e Jiayang Lin. "Modelling and numerical simulation optimization of output spectra of PbSe doped quantum dot fiber light source based on genetic algorithm". Applied and Computational Engineering 10, n.º 1 (25 de setembro de 2023): 79–85. http://dx.doi.org/10.54254/2755-2721/10/20230147.

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Optical fiber amplifiers mainly use rare earth elements as dopants. In the past 20 years, with the research on plastic optical fiber amplifiers doped with different natural elements (such as erbium and thulium), the performance of optical fiber amplifiers has been significantly improved. However, the application potential of natural elements has reached its limit. To improve optical communication, researchers are working on a fiber amplifier with a better flat gain and more intense light. In this paper, the quantum dot fiber amplifier is treated as a three-level structure, and a genetic algorithm is used to optimize the quantum dot fiber amplifier to maximize the total output power. In this study, by solving and analyzing the rate and power propagation equations of the numerical model, the gain spectrum of the amplifier at a wavelength of 1200~1700nm is obtained as a function of fiber length and doping concentration. Draw three-dimensional images based on fiber length, doping concentration, and ASE power axis to find the maximum power at the highest point of the image. Then, combined with the optimization results of the genetic algorithm, the maximum value of the total power is obtained.

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GRYCHKIN, S. E. "ENERGY EFFICIENCY INCREASING OF RADIO TRANSMITTERS". T-Comm 17, n.º 5 (2023): 25–31. http://dx.doi.org/10.36724/2072-8735-2023-17-5-25-31.

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At present, increasing the energy efficiency of radio electronic equipment is one of the most important tasks in the development and modernization of equipment for all radio services, and in some areas of application of radio electronic equipment, energy efficiency is critical. The main problems that occur in the development and operation of radio transmitting equipment are considered, and solutions are listed that can increase the efficiency of transmitters. Since the increase in energy efficiency is especially important for high-power power amplifiers of the final stages of transmitters, in this paper we analyze the radio transmitters switching operating modes, suitable for building modulators of the final stages of radio transmitters of digital broadcasting systems. The operating modes of switching power amplifiers and methods for achieving high energy efficiency of power amplifiers are discussed, their advantages and disadvantages are shown. The comparative analysis of circuits and classes of various types switching power amplifiers showed that each of them has a number of disadvantages that do not allow choosing the universal optimal version of such amplifier, so that the use of specific power amplifiers depends of the transmitter required characteristics. Another way is to use synthetic and combined methods for constructing high-performance power amplifiers to increase of the transmitters final stages resulting efficiency.

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Barmala, Ehsan. "Design and simulate a doherty power amplifier using GaAs technology for telecommunication applications". Indonesian Journal of Electrical Engineering and Computer Science 15, n.º 2 (1 de agosto de 2019): 845. http://dx.doi.org/10.11591/ijeecs.v15.i2.pp845-854.

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<span>In this paper, a Doherty power amplifier was designed and simulated at 2.4 GHz central frequency which has high efficiency. A Doherty power amplifier is a way to increase the efficiency in the power amplifiers. OMMIC ED02AH technology and PHEMT transistors, which is made of gallium arsenide, have been used in this simulation. The Doherty power amplifier unique feature is its simple structure which is consisting of two parallel power amplifiers and transmission lines. In order to integrate the circuit, the Doherty power transmission amplifier lines were implemented using an inductor and capacitive components. Also, the Wilkinson power divider is used on the chip input. To improve the efficiency, the auxiliary amplifier dimensions is selected enlarge and the further input power is allocated it by the power divider. A parallel R-C circuit has been used at the input of transistors to improve their stability. Simulation results show that the Doherty power amplifier has 17.2 dB output power gain, 23 dBm maximum output power, and its output power P<sub>1dB</sub> =22.6dBm at compression point -1 dB, also, its maximum efficiency is 55.5%.</span>

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Memioglu, O., O. Kazan, A. Karakuzulu, I. Turan, A. Gundel, F. Kocer e O. A. Civi. "Development of X-Band Transceiver MMIC’s Using GaN Technology". Advanced Electromagnetics 8, n.º 2 (24 de fevereiro de 2019): 1–9. http://dx.doi.org/10.7716/aem.v8i2.1012.

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This paper describes X-Band power amplifier (PA), low noise amplifier (LNA) and switches that can be used in transmit/receive modules which are developed with GaN technology. For Transmit chain two 25 W high power amplifiers that are tuned between 8-10 GHz and 10-12 GHz bands are designed. A low noise amplifier with 2 W survivability and less than 2dB noise figure is designed for receive chain Furthermore, an RF switch that is capable of withstanding 25 W RF power is developed for the selection of transmit or receive chains. Measurement results show that both power amplifiers produce 25 W of power. Low noise amplifier has more than 20 dB small signal gain with less than 2 dB noise figure. RF switch has 50 dB of isolation with less than 1 dB insertion loss.

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Iversen, Niels, Nicolai Dahl, Arnold Knott e Michael Andersen. "Higher Power Density Amplifiers". Journal of the Audio Engineering Society 66, n.º 12 (20 de dezembro de 2018): 1051–61. http://dx.doi.org/10.17743/jaes.2018.0064.

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Williamson, Robert C., e James J. Croft. "Audio frequency power amplifiers". Journal of the Acoustical Society of America 98, n.º 5 (novembro de 1995): 2399–400. http://dx.doi.org/10.1121/1.414401.

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Alizadeh, Amirreza, Majid Yaghoobi e Ali Medi. "Class-J2 Power Amplifiers". IEEE Transactions on Circuits and Systems I: Regular Papers 64, n.º 8 (agosto de 2017): 1989–2002. http://dx.doi.org/10.1109/tcsi.2017.2683067.

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Alizadeh, Amirreza, Milad Frounchi e Ali Medi. "Class-J23 Power Amplifiers". IEEE Transactions on Circuits and Systems I: Regular Papers 66, n.º 10 (outubro de 2019): 3664–75. http://dx.doi.org/10.1109/tcsi.2019.2913689.

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Franco, Marc. "Mobile handset power amplifiers". IEEE Microwave Magazine 10, n.º 7 (dezembro de 2009): 16–19. http://dx.doi.org/10.1109/mmm.2009.934687.

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Caverly, Robert, Frederick Raab e Joseph Staudinger. "High-Efficiency Power Amplifiers". IEEE Microwave Magazine 13, n.º 7 (novembro de 2012): S22—S32. http://dx.doi.org/10.1109/mmm.2012.2216716.

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O'Connell, Robert, Chih-Jung Huang, Armin Karabegovic e William Nunnally. "Optoelectronic Microwave Power Amplifiers". IEEE Transactions on Dielectrics and Electrical Insulation 14, n.º 4 (agosto de 2007): 994–1001. http://dx.doi.org/10.1109/tdei.2007.4286539.

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