Power Amplifiers Research Papers - Academia.edu (original) (raw)

2025, Optics Communications

Development of Er-doped ultrafast lasers have lagged behind the corresponding developments in Yb-and Tmdoped lasers, in particular, fiber lasers. Various applications benefit from operation at a central wavelength of 1.5 𝜇m and its second harmonic, including emerging applications such as 3D processing of silicon and 3D printing based on two-photon polymerization. We report a simple, robust fiber master oscillator power amplifier operating at 1.55 𝜇m, implementing chirp pulse amplification using single-mode fibers for diffraction-limited beam quality. The laser generates 80 nJ pulses at a repetition rate of 43 MHz, corresponding to an average power of 3.5 W, which can be compressed down to 175 fs. The generation of short pulses was achieved using a design which is guided by numerical simulations of pulse propagation and amplification and manages to overturn gain narrowing with self-phase modulation, without invoking excessive Raman scattering processes. The seed source for the two-stage amplifier is a dispersion-managed passively mode-locked oscillator, which generates a ∼40 nm-wide spectrum and 1.7-ps linearly chirped pulses.

2025, IEEE Transactions on Microwave Theory and Techniques

Operational behaviors of the class-F and class-F amplifiers are investigated. For the half-sinusoidal voltage waveform of the class-F amplifier, the amplifier should be operated in the highly saturated region, in which the phase relation between the fundamental and second harmonic currents are out-of-phase. The class-F amplifier can operate at the less saturated region to form a half sinewave current waveform. Therefore, the class-F amplifier has a bifurcated current waveform from the hard saturated operation, but the class-F amplifier operates as a switch at the saturated region for a second harmonic tuned half-sine waveform. To get the hard saturated operation, the fundamental load is very large, more than times larger than that of the tuned load amplifier. The operational behaviors of the amplifiers are explored with the nonlinear output capacitor. Since the capacitor generates a large second harmonic voltage with smaller higher order terms, the class-F amplifier with the nonlinear capacitor can deliver the proper half-sinusoidal voltage waveforms at a lower power, but the effect of the nonlinear capacitor is small for the class-F amplifier. The class-F amplifier delivers the superior performance at the highly saturated operation due to its larger fundamental current and voltage generation at the expense of the larger voltage swing. The simulation results lead to the conclusion that the class-F amplifier with the nonlinear capacitor is suitable topology for high efficiency. However, in the strict sense, the class-F amplifier with the nonlinear capacitor is not the classical class-F amplifier because the voltage-shaping mechanisms and the fundamental load are quite different. We call it the saturated amplifier since the amplifier is the optimized structure of the power amplifier operation at the saturated mode.

2025, IEEE Transactions on Microwave Theory and Techniques

2025, 2019 IEEE Topical Conference on RF/Microwave Power Amplifiers for Radio and Wireless Applications (PAWR)

In this paper, a new method for dynamically estimating and updating the coefficients of a digital predistortion (DPD) linearizer is presented. By means of the partial least squares (PLS) algorithm, the basis matrix used in the DPD estimation/adaptation is dynamically updated at every iteration to minimize the linearization error. Moreover, only the minimum necessary DPD coefficients being required to meet a target estimation error are computed. The proposed estimation technique is compared with the standard least squares (LS) estimation solved by using QR decomposition. Experimental results show the similar linearization performance obtained with both estimation methods, but in the case of the dynamic PLS, using less coefficients at every iteration. Finally, the proposed algorithm allows a high level of parallelization, which makes it suitable for FPGA implementation.

2025, 2018 IEEE/MTT-S International Microwave Symposium - IMS

This paper presents a new method, based on the adaptive principal component analysis (APCA) technique, that iteratively creates and updates an orthogonal data matrix used to estimate the parameters of power amplifier (PA) behavioral models or digital predistortion (DPD) linearizers. Unlike the conventional PCA, the proposed block deflacted APCA (BD-APCA) is an iterative and online method that can be easily implemented in embedded processors. The proposed BD-APCA is designed by properly modifying the well-known complex domain generalized Hebbian algorithm (CGHA). This adaptation method enhances the robustness of the parameter estimation, simplifies the adaptation by reducing the number of estimated coefficients and due to the orthogonality of the new basis, these parameters can be estimated independently, thus allowing for scalability. Experimental results show that the proposed BD-APCA method is a worthy solution for adaptive, online, reduced-order and robust parameter estimation for PA modeling and DPD.

2025, 2018 IEEE Topical Conference on RF/Microwave Power Amplifiers for Radio and Wireless Applications (PAWR)

This paper presents a multi lookup table (LUT) implementation scheme for the 3D distributed memory polynomial (3D-DMP) behavioral model used in Digital Predistortion (DPD) linearization for concurrent dual-band envelope tracking (ET) power amplifiers (PAs). The proposed 3D-Distributed Memory LUTs (3D-DML) architecture is suitable for efficient FPGA implementation. In order to optimize the linearization performance as well as to reduce the number of resources of the 3D-DML model, a new variant of the Orthogonal Matching Pursuit (OMP) algorithm is proposed to properly select the best LUTs. Experimental results show that the proposed strategy reduces the number of LUTs (i.e. the number of coefficients) while meeting the targeted linearity levels.

2025, IEEE Transactions on Microwave Theory and Techniques

This paper presents a new technique that dynamically estimates and updates the coefficients of a digital predistorter (DPD) for power amplifier (PA) linearization. The proposed technique is dynamic in the sense of estimating, at every iteration of the coefficient's update, only the minimum necessary parameters according to a criterion based on the residual estimation error. At the first step, the original basis functions defining the DPD in the forward path are orthonormalized for DPD adaptation in the feedback path by means of a precalculated principal components analysis (PCA) transformation. The robustness and reliability of the precalculated PCA transformation (i.e., PCA transformation matrix obtained off-line and only once) is tested and verified. Then, at the second step, a properly modified partial least squares (PLS) method, named dynamic partial least squares (DPLS), is applied to obtain the minimum and most relevant transformed components required for updating the coefficients of the DPD linearizer. The combination of the PCA transformation with the DPLS extraction of components is equivalent to a canonical correlation analysis (CCA) updating solution, which is optimum in the sense of generating components with maximum correlation (instead of maximum covariance as in the case of the DPLS extraction alone). The proposed dynamic extraction technique is evaluated and compared in terms of computational cost and performance with the commonly used QR decomposition approach for solving the least squares (LS) problem. Experimental results show that the proposed method (i.e., combining PCA with DPLS) drastically reduces the amount of DPD coefficients to be estimated while maintaining the same linearization performance.

2025, IEEE Transactions on Microwave Theory and Techniques

This paper presents an estimation/adaptation method based on the adaptive principal component analysis (APCA) technique to guarantee the identification of the minimum necessary parameters of a digital predistorter. The proposed estimation/adaptation technique is suitable for online fieldprogrammable gate array (FPGA) or system on chip (SoC) implementation. By exploiting the orthogonality of the resulting transformed matrix obtained with the APCA technique, it is possible to reduce the number of coefficients to be estimated which, at the same time, has a beneficial regularization effect by preventing ill-conditioning or over-fitting problems. Therefore, this identification/adaptation method enhances the robustness of the parameter estimation, simplifies the adaptation by reducing the number of estimated coefficients. Due to the orthogonality of the new basis, these parameters can be estimated independently, thus allowing for scalability. Experimental results will show that it is possible to determine the minimum number of parameters to be estimated in order to meet the targeted linearity levels while ensuring a robust well-conditioned identification. Moreover, the results will show how thanks to the orthogonality property of the new basis functions, the coefficients of the digital predistorter can be estimated independently. This allows to trade-off the digital predistorter adaptation time versus performance and hardware complexity.

2025, 2012 Workshop on Integrated Nonlinear Microwave and Millimetre-wave Circuits

This paper reports a package synthesis method in order to ensure good performances in PAE, output power and bandwidth. The internal matching circuits of the optimized package enable to reach the best impedance pre-matching at fundamental frequencies and also to confine the harmonic impedances seen by the internal GaN power bar into safe efficiency regions whatever the external impedances presented to the package at second harmonic frequencies. In a 500 environment, the packaged GaN HEMT delivers 55 W output power associated with 60% PAE and 13.3 dB power gain at 2.7 GHz. By optimizing source and load impedances at the fundamental frequencies, the packaged GaN HEMT demonstrates more than 58% PAE from 2.6 GHz to 3.0 GHz.

2025, 2017 IEEE MTT-S International Microwave Symposium (IMS)

In this paper, we propose a simple polynomial linearisation technique for nonlinear phased arrays including amplitude control. Due to the large number of antennas and thus power amplifiers in the array, it is inefficient to linearise each power amplifier individually. Therefore, it is demonstrated that the array can be linearised over-the-air using single polynomial. The simulations show that the linearisation is achieved by first linearising the higher driven PAs at the precompression region and then cancelling the compression by the heavily expanding lower driven PAs. The proposed approach offers an alternative way of re-thinking the concept of array linearisation over multiple PAs.

2025, beginning on

Since the drain capacitance of the SD57030 is 36.5 pF at 900 MHz, true tran-sient class-E operation is not possible. The class-E configuration is therefore based upon a second-harmonic approximation to class-E operation. A second-harmonic... more

2025, SIMULASI RANGKAIAN DIODA TRANSISTOR PADA APLIKASI PROTEUS

Materi ini membahas dan menganalisis hasil simulasi tentang dioda dan transistor, ditunjang dengan Proteus sebagai bagian komprehensif dari Ujian Tengah Semester mata kuliah Elektronika. Dan tujuan utama artikel ini adalah memberikan mahasiswa pemahaman yang lebih dalam dari konsep dasar tentang elektronik, khususnya dioda dan transistor serta penggunaannya di berbagai macam bentuk rangkaian, dari hasil analisis simulasi rangkaian berbagai jenis, seperti dioda forward-biasing dan reverse-biasing circuits, gelombang penuh penyearah, dan metode bias dengan BJT menggunakan rangkaian yang berlainan. Dalam setiap rangkaian yang disimulasikan mengikuti sesuai langkah-langkah pada proteus, kemudian hasil dibandingkan dengan perhitungan manual yang berdasarkan teori sehingga dapat divalidasikan atau dibandingkan

2025, DGBC-UC (Dirección General de Bibliotecas y Centros de Documentación - Universidad de Carabobo)

El amplificador de potencia es un elemento esencial en cualquier sistema de comunicaciones y es inherentemente no lineal. La no linealidad del amplificador crea recrecimiento espectral, aumentando la emisión de potencia a los canales... more

2025, Active and Passive Electronic Components

Recent advances in printed circuit and packaging technology of microwave and millimeter wave circuits result to the increasing use of MMICs in telecommunication systems. At Microwave and Fiber Optics Lab of NTUA several designs of various MMICs were conducted using the HP Eesof CAD Tool and FET and HEMT models of F20 and H40 GaAs foundry process of GEC Marconi. The designed MMICs are constructed in Europractice Organization while on-wafer probe measurements are performed in the Lab. In that framework, MMIC technologies are employed in the design of power and low noise amplifiers and couplers to be used for mobile and wireless communications as well as remote sensing and radar applications. A medium power linear FET amplifier has been designed with combining techniques on a single chip. The circuit operates at 14.4–15.2 GHz with an input power of−15dB m, a 36 dB total gain, while the input and output VSWR is less than 1.6. Due to high cost of MMIC fabrication only the first subunit w...

2025, IEEE Transactions on Wireless Communications

2024, Journal of Central South University

Radio frequency identification (RFID) is a ubiquitous identification technology nowadays. An on-chip high-performance transmit/receive (T/R) switch is designed and simulated in 0.13-µm CMOS technology for reader-less RFID tag. The switch utilizes only the transistor width and length (W/L) optimization, proper gate bias resistor and resistive body floating technique and therefore, exhibits 1 dB insertion loss, 31.5 dB isolation and 29.2 dBm 1-dB compression point (P1dB). Moreover, the switch dissipates only 786.7 nW power for 1.8/0 V control voltages and is capable of switching in 794 fs. Above all, as there is no inductor or capacitor used in the circuit, the size of the switch is 0.00208 mm 2 only. This switch will be appropriate for reader-less RFID tag transceiver front-end as well as other wireless transceivers operated at 2.4 GHz band.

2024, International Journal of Electrical and Computer Engineering (IJECE)

The two circuit-level parasitic compensation techniques for the Philips metal oxide semiconductor (MOS) model 9 metal oxide semiconductor field effect transistor (MOSFET) at high frequencies (in the GHz range) are presented in this paper. The first method involves connecting the series resonant LC circuit in parallel to the drain and grounded source/bulk of the MM9; the second method involves connecting two of these MM9s in parallel to increase the drain current at higher frequencies along with parasitic compensation. Using these compensatory techniques, it is possible to reduce the impact of drain-source parasitic capacitance on MOS model 9 by preventing the short circuit of MOSFET terminals at high frequencies. After adjustment, improvements were seen in a number of metrics, including output impedance, S-parameters, output power and stability. Finally, using a 10 dBm source power, these parasitic compensation techniques are applied to a single and two stage basic class-E power amplifier and simulated at 1.7 and 1.1 GHz, respectively. Improvements are noted in multiple performance parameters, including power Gain (16.5 dB), drain Efficiency (83%), power added efficiency (85.82%), output power (26 dBm), good Stability (K=2.23, B>0), and S-parameters (S11=-9.22 dB, S12=-39.78 dB, S21=16.38 dB, and S22=1.41 dB) in two-stage cascade power amplifier.

2024, 2024 IEEE Biennial Congress of Argentina (ARGENCON)

We present the design and implementation of a power combining amplifier that has a bandpass response, providing high rejection to spurious frequencies and intermodulation products that are usually generated in transmission systems. The proposed architecture consists of two identical power amplifiers interconnected with compact microstrip filtering power dividers and combiners. A prototype capable of operating at 2.3 GHz was fabricated to validate the design. The obtained measurement results demonstrate that high out-of-band rejection is achieved, while the 1 dB compression point is enhanced about 1.6 dB with respect to the individual amplifiers. In addition, thanks to the low insertion loss of the combining components, the total gain of the system is not considerably reduced.

2024, Electronics & Communication Engineering Journal

In order to meet the linearity specification of standards such as GSM EDGE and TETRA the power amplifier (PA) linearisation methods in common usage today result in low DC to RF efficiency (e.g. Cartesian loop and adaptive predistortion). The transmitter places a heavy demand on the battery and therefore utilising more efficient transmitters can increase talk-time or reduce the battery size. For GSM EDGE and TETRA modulation it is shown that to obtain a transmitter efficiency (of >50%) the PA needs to be biased as class-C. The effect power amplifier efficiency has on talk-time is demonstrated for a handportable with fixed power overhead owing to the digital processing required to compile and transmit a burst or packet. It is shown that the PA efficiency for a transmitter operating backed-off (under power control), has a marginal impact on the talk-time and that the effect is largest at high output powers. This is put in context by a review of the various linearisation schemes such as Cartesian loop, polar loop, 2 nd harmonic injection, envelope elimination & restoration (EER), predistortion methods, and synthesis techniques (e.g. LINC & CALLUM). The review also discusses which methods are not suitable for handportable design, and documents the strengths and weaknesses of the remaining methods. The paper shows that to increase the power efficiency (and thus talk-time), hybrid solutions to power amplifier linearisation are required. Finally, existing hybrid solutions and their shortfalls are discussed.

2024, 2015 International Conference on Electromagnetics in Advanced Applications (ICEAA)

Design of low loss with an enhanced thermal profile power divider/combiner for high power dual-band Radio Frequency (RF) power amplifier applications is given. The practical implementation, low loss and substrate characteristics make this type of combiner ideal for high power microwave applications. The combiner operational frequencies are chosen to operate at 900 MHz and 2.14 GHz, which are common frequencies for concurrent dual band RF power amplifiers. The analytical results are verified with simulation results for various cases and agreement has been observed on all of them.

2024, ReasearchGate

Portable real-time ECG monitor has to resolve many problems related to normal activity and physical exercise as compared to clinical monitors or Normal printing monitors. The most important problems include baseline wandering, muscle activity noise, changing electrode resistance (gel drying), lead problems, lead resistances etc. All these problems lead to decreased monitor reliability. In this project we have reduced these issues involved in development of a real-time, portable, PC based ECG monitoring device. The most important issues include reliable real-time processing of ECG morphology and power efficient processing.
We have improved the reliability of real time ECG monitoring system with the help of high gain instrumentation amplifiers like AD624AD & AD620. After processing the ECG signal from our circuit, we moved it into the parallel port of computer where Heart Beat Analyzer’s software already waits for the ECG signal. This code brings the ECG signal and then plots these signals into three different graphs for three different Leads.
We have improved the reliability using redundant signal processing procedures. For example, detection of R-peak is implemented using several known techniques. The number of detected R-peaks in the time/amplitude window that is defined using statistical expectations determines if the detection was reliable. In the time domain, R-peak is expected within 70-160% of the average RR (R to R peak) period, and within the expected amplitude range. With the help of these R-R Peaks, we have determined the Heart rate. If the single peak is detected in the given window no alternative processing methods are necessary.
Additional experiments related to energy consumption and battery life were conducted using our energy? Profiling environment. Due to non-ideal battery characteristics, only experimental approach can provide valid data for prototype evaluation. Our environment consists of a PC, high resolution digital Oscilloscope, Rims emulator (for checking purposes), and a workstation that controls devices and stores the traces. We use AD624AD Instrumentation Amplifiers (to amplify the 2mV signal into 1-2V).

2024

2024, IEEE Transactions on Microwave Theory and Techniques

2024, 2018 IEEE/MTT-S International Microwave Symposium - IMS

2024, IEEE

A modified varactor device using Barium Strontium Titanate (Ba0.6Sr0.4TiO3) thin films for low loss millimeter wave frequency applications is demonstrated in this paper. MIM (Metal Insulator Metal) varactor devices with splits in the signal line presented in this work has >7:1 tunability for 35-50 GHz frequency range. The overall capacitance of the device changes from 0.19 pF to 0.025 pF with 0V-10V DC bias voltage applied. The device has very low insertion loss of 0.9 dB with 10 V DC bias voltage applied at 50 GHz.

2024, Texas Instruments

While in the process of reviewing Texas Instruments applications notes, including those from Burr-Brown-I uncovered a couple of treasures, this handbook on op amp applications and one on active RC networks. These old publications, from 1963 and 1966, respectively, are some of the finest works on op amp theory that I have ever seen. Nevertheless, they contain some material that is hopelessly outdated. This includes everything from the state of the art of amplifier technology, to the parts referenced in the document-even to the symbol used for the op amp itself:

2024

3,860,876 l/1975 Woods ................................ 328/167 3,939,428 2/1976 Shimizu et al. . 3,973,461 8/1976 Johns . 4,000,474 12/1976 Todokoro ............................. 330/35 4,143,245 3/1979 Scholz . 4,180,707 12/1979 Moog. 4,21 1,893 7/1980 Smith . 4,286,492 9/1981 Claret . 4,439,742 3/1984 Sondermeyer ...................... 330/262 4,538,297 8/1985 Waller, Jr. ......... ... 38/94 4,578,818 3/1986 Claydon ..... . 455/10 4,628,789 12/918.6 Fujimori..... ... 381/61 4,680,795 7/1987 Ecklund ..... ... 381/5 4,683,589 7/1987 Scholz et al. ... 38A6 4,701,956 10/1987 Katoh ............. ... 38/61 4,803,731 2/1989 Mimi et al. ........................... 381/63

2024, International Journal of Power Electronics and Drive Systems (IJPEDS)

This article reveals the conceptualization and implementation of energy harvesting system that utilize piezoelectric arrays within environments marked by elevated ambient noise levels. The selected methodology involves conducting an empirical study where the system is introduced into a room with pronounced ambient noise. A series configuration is adopted for assembling the piezoelectric sensors. For this particular experiment, 36 piezoelectric sensor units were arranged, each equipped with a voltage doubler circuit, aiming to harness a specific micropower energy threshold. The experimental results validate the successful development of an energy harvesting mechanism employing a piezoelectric array within a noisy setting. Notably, the device functions optimally at a frequency of 250 Hz. Additionally, a series of controlled experimental tests were executed at a sound level of 95.8 dBA to assess the efficacy of the piezoelectric array. Measurements taken at the voltage doubler output reveal that the device achieves its peak output signal at 3.32 Vpp and 50.42 Hz. The maximum attainable direct current (DC) voltage stands at 1 Volt, complemented by a current of 0.45 mA.

2024, IEEE

This paper presents the design and performance evaluation of a 0.15um GaN Ka-band power amplifier using the Monolithic Microwave Integrated Circuit (MMIC) technique for satellite communication. Low loss prototype network are designed using Win semiconductor's 0.15um GaN process design kit(PDK). The amplifier achieves stability greater than 1.5, with S-parameter characteristics exhibiting S11 less than-10 dB, S21 greater than 10 dB, S22 less than-10 dB. Furthermore, a power added efficiency (PAE) of 25% is achieved. The results demonstrate the viability of the designed power amplifier for efficient and high gain in Ka-band satellite communication applications.

2024, 2018 IEEE/MTT-S International Microwave Symposium - IMS

2024, IEEE Transactions on Microwave Theory and Techniques

2024, 2006 IEEE Radio and Wireless Symposium

2024, 2010 IEEE International Microwave Workshop Series on RF Front-ends for Software Defined and Cognitive Radio Solutions (IMWS)

This paper assesses the PAPR for multimode transmitters (WiMAX, WiFi and Bluetooth), considering different combinations of modulations and access techniques (spreading codes and OFDM). Simulations include preamble, header and data fields. Results give hints for tailoring the back-off of power amplifiers, as well as for foreseeing the necessary slew-rate in polar transmitters.

2024, Advances in Radio Science

In this paper a new filter design concept is proposed and implemented which takes into account the complex loudspeaker impedance. By means of techniques of broadband matching, that has been successfully applied in radio technology, we are able to optimize the reconstruction filter to achieve an overall linear frequency response. Here, a passive filter network is inserted between source and load that matches the complex load impedance to the complex source impedance within a desired frequency range. The design and calculation of the filter is usually done using numerical approximation methods which are known as Real Frequency Techniques (RFT). A first approach to systematic design of reconstruction filters for class-D amplifiers is proposed, using the Simplified Real Frequency Technique (SRFT). Some fundamental considerations are introduced as well as the benefits and challenges of impedance matching between class-D amplifiers and loudspeakers. Current simulation data using MATLAB is...

2024, IOP Conference Series: Earth and Environmental Science

Recently, the design of RF power amplifiers (PAs) for modern wireless systems are faced with a difficult tradeoff for example, cellphone; battery lifetime is largely determined by the power efficiency of the PA and high spectral efficiency which have ability to transmit data at the highest possible rate for a given channel bandwidth. This paper presents the design a multi stage class AB power Amplifier with high power added efficiency (PAE) and acceptable linearity for the WLAN applications. The open-circuited third harmonic control circuit enhances the efficiency of the PA without deteriorating the linearity of class-AB mode of the PA. The voltage and current waveforms are simulated to evaluate the appropriate operation for the modes. The effectiveness of the proposed controller has been verified by comparing proposed method with another methods using simulation study under a variety of conditions. The proposed circuit operation for a WLAN signals delivers a power-added efficiency (PAE) of 37.6% is measured at 31.6-dBm output power while dissipating 34.61 mA from a 1.8V supply. Finally, the proposed PA is show a good and acceptable result for the WLAN system.

2024, 2016 IEEE Radio and Wireless Symposium (RWS)

Multiple factors must be considered in poweramplifier design for wireless communications and radar, including bias voltage, input power, and load impedance. The Bias Smith Tube is presented as a three-dimensional extension of the Smith Chart with bias voltage as the vertical axis. It allows simultaneous visualization of nonlinear output characteristic behaviors over transistor bias voltage and load reflection coefficient. Simulated and measured threedimensional surfaces of constant power-added efficiency (PAE), adjacent channel power ratio (ACPR), and delivered power are shown in the Bias Smith Tube, and a design approach is illustrated that finds the combination of load impedance and bias voltage providing maximum PAE under ACPR and/or delivered power constraints.

2024, International Journal of Power Electronics and Drive Systems (IJPEDS)

Considering the massive development that took place in the past two decades, wireless power transfer has yet to show the applicability to be used due to several factors. This work focuses on determining the main parameters like, mutual inductance, and coupling coefﬁcient for a pair of helical coils for wireless power transfer applications. These parameters are important in designing and analyzing a wireless power transfer system based on the phenomenon of inductive/ resonant inductive coupling. Here presents a simple approach based on fundamental laws of physics for determining the coupled coil parameters for single layered helical coils. The results conducted by computer simulation which is MATLAB. Furthermore, this analysis is used to study the effect of change in coil diameter, mutual inductance coefficient and change in distance between coils on parameters like self and mutual inductance of coupled coils which is of great importance in Wireless Power Transfer applications. The r...

2024

The immunity of operational amplifiers is a trend topic for electromagnetic compatibility EMC community. Radiofrequency interference is usually applied to the operation amplifier and the voltage offset is monitored as a parameter to evaluate the EMC degradation. However, this method does not provide enough information to know the probability of failure to electromagnetic interference of the devices. In this paper, an alternative statistical analysis based on the Weibull distribution is used to analyze the electromagnetic immunity performance of operational amplifiers under different frequency interferences and modulation index. The results confirm the feasibility of the Weibull distribution to evaluate the radiofrequency interference RFI behavior.

2024, IEICE Electronics Express

It is accepted that the electromagnetic interference should be addressed with statistical analysis. Usually the impact of electromagnetic interference on different electronic samples is evaluated and the average immunity level is used as a reference. However, this method does not provide enough information to know the probability of failure to the electromagnetic interferences of an electronic circuit. An alternative statistical analysis based on the Weibull distribution is presented. The typical and proposed methods have been compared in order to analyse the electromagnetic immunity performance of two types of operational amplifier. The results confirm the feasibility of the proposed method.

2024

Em primeiro lugar agradeço à Deus pelo objetivo alcançado. Agradeço à Ele também pela boa saúde e bem-estar de meus familiares e amigos. Agradeço aos meus pais, Luciano e Keila, pela dedicação, incentivo e carinho. Ao meu orientador, Prof. José Rubens Macedo Júnior, deixo expresso meus sinceros agradecimentos por toda a confiança e ensinamentos, fundamentais para a concretização deste trabalho. Aos meus grandes amigos Arnaldo, Isaque e Leandro, pela força ativa para conclusão desse trabalho. Aos meus colegas de Celg Geração e Transmissão pela compreensão e incentivo a educação. Enfim, a todos aqueles que, direta ou indiretamente, contribuíram para a realização deste trabalho. vi RESUMO Esse trabalho tem como foco principal a análise da influência que as distorções harmônicas e os desequilíbrios exercem nos erros de medição de energia elétrica em medidores de faturamento trifásicos de potência ativa e reativa. Tais equipamentos tipicamente são concebidos para serem instalados em plantas elétricas totalmente equilibradas e simétricas, fato esse que não reflete as atuais condições da rede de distribuição. Inicialmente, levantou-se as metodologias de cálculo de potência mais relevantes da literatura, sendo suas equações implementadas em ambiente computacional (MATLAB), visando obter indicadores comparativos entre elas. Obtidos os resultados comparativos, montou-se uma estrutura laboratorial padrão para ensaios de medidores de energia, onde os mesmos foram submetidos a uma bateria de ensaios com diferentes níveis de distorções harmônicas e desequilíbrios, conforme o caderno de testes proposto. Realizados os ensaios, notou-se uma grande incoerência entres os resultados obtidos por cada medidor, sendo assim necessário recomendar uma metodologia de cálculo alternativa capaz de padronizar as medições de modo a não prejudicar as partes envolvidas, seja a concessionária de energia elétrica ou o consumidor final. Com base na recomendação feita, a mesma foi implementada em um protótipo de medidor, juntamente com as demais metodologias, para fins comparativos. Por fim, foi realizada uma campanha de medição em diferentes plantas, com o protótipo, onde os resultados obtidos para medição de potência ativa apresentaram baixo desvios em relação a classe de exatidão dos medidores. No entanto, quando considerada a energia reativa, as diferentes metodologias apresentaram desvios superiores a 20 por cento em algumas plantas. Palavras-chave: fator de potência, medidores de energia elétrica, qualidade da energia elétrica, resultados experimentais.

2024, Journal of the Optical Society of America B

of America]. La impressió o còpia electrònica es poden fer només per a ús personal. La reproducció, la distribució, la duplicació amb finalitats comercials i la modificació de continguts queden prohibides.

2024, International Journal of Power Electronics and Drive Systems (IJPEDS)

2024

The 5G is a complete communication system, covering many radio communication standards, within its devices several integrated components meet a variety of standards for physical layer of the 5G communication networks: sub-6 GHz, IEEE Std 802.11n-2009, IEEE Std 802.11ac-2013, Bluetooth and UWB. There is a need for a flexible and adaptable RF power amplifier (PA) component to avoid the repetition of
amplifiers, using different frequencies, in a 5G device, as well as the repetition of building blocks, also of different frequencies, within an PA integrated circuit (IC). In this work, a methodology is proposed for the design and development of a wideband PA with a single mode of operation, capable of transmitting in different communication
standards. Compared with the state of the art, this PA will have good linearity across the projected band, instead of a sweet spot at a given frequency, as found in the literature. The PA IC developed has two stages: a PPA pre-amplification stage that uses a current reuse technique and a cascode power stage. Initially, the stages were designed using conventional transistors, later the multiplicity of transistors was changed to improve the performance and linearity parameters. Tests were carried out replacing conventional transistors with triple-well type for an accurate control of the threshold voltage. A narrow band impedance matching was made, both at the input and at the output but the wideband behavior was maintained. The PA was validated with modulated signal tests in three communication standards and post-layout simulations. The designed PA is a class AB and operates in the 2-5 GHz range. The results of the simulations: a power gain of 16-20.9 dB, an output saturation power of 19.1-21.7 dBm, a compression point of 15.8-20.4 dBm and a power added efficiency of 9.28-22.4%. Although there are no measurements of the PA IC, the performance data obtained by post-layout simulations and the results of the three-band modulated signal tests corroborate the potential of the proposed methodology for the design of wideband PA. The PA was also a physical model for behavioral modeling of projects that implement the linearization of PAs by digital pre-distortion, with transmission of multi-band signals.

2024, Radioengineering

In this paper, we propose an efficient approach for optimizing the decomposed vector rotation (DVR) model for digital predistortion (DPD). The DVR model's basis functions are constructed piecewise by dividing the input space into segments bounded by thresholds. This paper investigates how to set the thresholds optimally using an iterative approach based on the decomposition of the global optimization problem into a set of unimodal sub-problems so that a unidirectional minimization can be used to optimize the positions of thresholds. The proposed approach has been evaluated using measurements from a real power amplifier (PA). The experimental results illustrate the efficiency of the proposed optimization approach and show that the thresholds' optimization improves linearization performances significantly compared to conventional DVR with uniform segmentation.

2024, Radioengineering

This paper presents a general survey of digital predistortion (DPD) techniques with segmentation. A comparison of global DPD with two segmented approaches namely Vector-Switched DPD and Decomposed Vector Rotation DPD is presented with the support of experimentation on a strongly non-linear 3 ways Doherty PA. It shows the interest of both segmented approaches in terms of linearization performance, complexity and ease of implementation compared to the global DPD. The paper starts with some mathematical generalities on interpolation and splines. It focuses on segmented models derived from Volterra series even if the presented principles can also be applied to neural networks.

2024, Learning and Nonlinear Models

Multiple-input multiple-output (MIMO) Volterra models have applications in different areas, including telecommunications. An overview of the modeling of nonlinear communication channels using MIMO Volterra models is presented in this paper. First, the development of an equivalent baseband discrete-time representation of a single-input single-output (SISO) Volterra system is carried out. This development constitutes the basis for several versions of discrete-time equivalent baseband MIMO Volterra systems presented in the sequel. The spectral broadening provided by a Volterra system on the equivalent baseband received signals is shown by calculating the frequency domain representation of the Volterra channel output. Some important block structured nonlinear MIMO models are also described, with their link to MIMO Volterra models. Finally, some applications of such models for communication systems are briefly discussed.

2024, 2015 IEEE 16th Annual Wireless and Microwave Technology Conference (WAMICON)

Future wireless networks will employ unprecedentedly high number of transmitters along-with larger bandwidth signals. Therefore, complexity efficient Power Amplifier (PA) modelling methods with the ability to quantify memory effects are required. This paper presents a low complexity method to quantify memory effects by studying the symmetry in the PA transfer functions estimated with the density estimation method. It is shown that the symmetry helps in reducing the method complexity by more than two orders of magnitude. Further, it is verified that the symmetry can be used as a non-model based metric for quantifying memory effects in PAs.