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

Power amplifiers (PAs) are among the most crucial functional blocks in the radio frequency (RF) frontend for reliable wireless communication. PAs amplify and boost the input signal to the required output power. The signal is amplified to make it sufficiently high for the transmitter to propagate the required distance to the receiver. Attempted advancements of PA have focused on attaining high-performance RF signals for transmitters. Such PAs are expected to require low power consumption while producing a relatively high output power with a high efficiency. However, current PA designs in nanometer and micrometer complementary metal–oxide semiconductor (CMOS) technology present inevitable drawbacks, such as oxide breakdown and hot electron effect. A well-defined architecture, including a linear and simple functional block synthesis, is critical in designing CMOS PA for various applications. This article describes the different state-of-the art design architectures of CMOS PA, includin...

- by
- •
- Electronics, Low Power Design, Power Amplifiers, CMOS Technology

Multimode multiband (MMMB) power amplifiers have been developed in recent years for next generation mobile handsets and tablets applications. Designers face new and greater challenges due to more stringent requirements in functionality, performance, size and cost. This paper will discuss the motivations that drive MMMB PA development and the requirements, challenges and considerations relevant to power amplifier design.

- by Ray Z
- •
- Wireless Communications, Amplification, Mobile, Multiband Signals

A qualitative analysis of different parameters such as Phase noise, Slew rate and tranconductance by using power gating reduction technique is presented. The circuit achieves the large driving capability by employing simple comparators to sense the transients of the input to turn on the output stages, which are statically off in the stable state. The effect of the different number of transistors and their topologies on the phase noise and Slew rate is analyzed. Good agreement between qualitative and quantitative measurements is observed. Scope of reducing of Noise and avoidance of Leakage due to various sources is discussed.

In this paper, a two-stage 0.18 μm CMOS power amplifier (PA) for ultra-wideband (UWB) 3 to 5 GHz based on common source inductive degeneration with an auxiliary amplifier is proposed. In this proposal, an auxiliary amplifier is used to place the 2nd harmonic in the core amplified in order to make up for the gain progression phenomena at the main amplifier output node. Simulation results show a power gain of 16 dB with a gain flatness of 0.4 dB and an input 1 dB compression of about-5 dBm from 3 to 5 GHz using a 1.8 V power supply consuming 25 mW. Power added efficiency (PAE) of around 47% at 4 GHz with 50 Ω load impedance was also observed. Keywords: CMOS Low noise amplifier Power amplifier Topologies Ultra-wideband (UWB) This is an open access article under the CC BY-SA license.

This paper presents a highly efficient power transfer system based on a co-design of a class-E power amplifier (PA) and a pair of inductively coupled Helical coils for through-metal-wall power transfer. Power is transferred wirelessly through a 3.1-mm thick aluminum barrier without any physical penetration and contact. Measurement results show that the class-E PA achieves a peak power gain of 25.2 dB and a maximum collector efficiency of 57.3%, all at 200 Hz. The proposed system obtains a maximum power transfer efficiency of 9% and it can deliver 5 W power to the receiver side through the aluminum barrier.

Answer all questions and enter your answers on ETHUTO on the spaces provided. Please SAVE and SUBMIT ALL answers 10 minutes before the end of the Timed Assignment session, as NO ANSWERS will be marked when submitted 2 minutes beyond the... more

- by Lerato Selepe
- •
- Power Amplifiers, Band Pass Filter, Amplifier, Oscilador

This contribution introduces a novel broadband power amplifier (BPA) design, operating in the frequency band ranging from 1.5 GHz to 3 GHz which cover the mainstream applications running in L and S bands. Both matching and biasing networks are synthesized by using microstrip transmission lines. In order to provide a wide bandwidth, two broadband matching techniques are deployed for this purpose, the first technique is an approximate transformation of a previously designed lumped elements matching networks into microstrip matching circuits, and the second technique is a binomial multi-sections quarter wave impedance transformer. The proposed work is based on ATF-13786 active device. The simulation results depict a maximum power gain of 16.40 dB with an excellent input and output matching across 1.5 GHz ~ 3 GHz. At 2.2 GHz, the introduced BPA achieves a saturated output power of 16.26 dBm with a PAE of 21.74%, and a 1-dB compression point of 4.5 dBm input power level. The whole circuitry is unconditionally stable over the overall bandwidth. By considering the broadband matching, the proposed design compares positively with the most recently published BPA. Keywords: Broadband biasing Broadband matching L and S bands Microstrip Power amplifier

A microwave power amplifier is a system level device responsible for enhancing the power levels on an input signal to a predefined level. Microwave power amplifiers are considered to be one of the most important components in many of the communication applications. Power amplifiers are divided into several classes, each having its unique and distinctive characteristics. Different classes are used for different purposes and applications. This paper focuses on designing and simulating four different classes of power amplifiers, class A, B, C and AB. The power amplifier will be designed using a MOSFET that will be operating with a max DC drain voltage of 28volts and a max drain current of 1Amps. This paper will also compare and contrast the efficiency and linearity trade-off associated with these classes of amplifier. Modulation excitation for these amplifiers will also be explored using the two tone method. Finally, the linearity of the different power amplifiers will be assessed using methods such as the ACPR and EVM. ADS was used to create the simulation. The transistor used for the purpose of designing the amplifier is MOSFET transistor. Using suitable biasing point and the tuning function provided by the ADS, different classes of amplifiers were simulated. The characteristics of these amplifiers are discussed thoroughly and different tests were performed in the ADS to assess the linearity of the power amplifier. The result obtained in the ADS matched results obtained from real life power amplifiers.

The aim of this laboratory work is to get practical experience with BJT and FETs. From theory, we know that Field Effect Transistors are voltage controlled unlike from BJTs, which are current controlled devices. There are Source, Gate and Drain electrode sides. The Gate electrode voltage is used to control Drain-Source characteristics. In this lab, we are to obtain the results in order to prove above said.
Equipment used:
- Power Supply PS1-PSU/EV
- Module MCM4/EV
- Multimeter
- Jumpers

Operational Amplifier (Op Amp) is a three terminal electronic device which has two inputs of high impedance. The first input is called inverting (represented by ‘-‘), and the other terminal is called non-inverting input. The third terminal serves as output port, where signal is usually amplified by some gain (A), depending on the nature of op amp and input characteristics.
In this lab session we build op amp circuits and carry out various calculations of op amp characteristics. At the end of this lab, we are to strengthen theoretical knowledge by gaining hands on experience. This lab covers:
- Inverting Amplifiers
- Non-inverting Amplifiers
- Summing Amplifiers

This paper presents the design of folded cascode operational transconductance amplifier (OTA). This design has been implemented in 0.18um CMOS Technology using Cadence. Spectre simulation shows that the OTA has flat gain of 47dB from 1Hz to 100 KHz frequency, indicating stability of OTA, noise ranges as 22.49769nV/ at 10Hz to 66.89128fV/ at 1MHz and average power as 0.770mW. In this paper, we will be studying the design concepts, analysis of operational transconductance amplifier which is used for recording the bio signals. This paper plays a key role in real time applications for equipment designing of ECG, EEG, EMG, ENG devices. It is also used in recording and also for treatment of Paralysis, Epilepsy, Neuro diseases etc.,

The design of a linear integrated Op Amp circuit as an alternative solution to differential equation model of RLC Circuit is presented. The fundamental assumption used in the cascaded Operational Amplifier (Op Amp) design is that Op Amp acts linearly. In this paper, we will examine the behavior of the Op Amp when it is used in the cascaded circuit that is an electrical analog to the differential equation model of RLC circuit, which arises in numerous applications particularly in control and communication systems such as ringing circuits, resonant circuits, filters and oscillators. We will design the cascaded op amp circuit that is analog to differential equation model of RLC circuit and obtain graphical results of output function versus time using PSpice Software Probe. To confirm the validity of the design of a linear integrated Op Amp circuit as an alternative solution to differential equation model of RLC circuit implemented in the PSpice Software, simulation results are compared with RLC circuit where we find good agreement between the theoretical predictions of the differential equation model of RLC circuit and the design of a linear integrated Op Amp circuit.

Bộ khuếch đại công suất (Power Amplifier) là gì? Tìm hiểu về ứng dụng, những loại bộ khuếch đại công suất hiện đang có trên thị trường Thông tin liên hệ Công ty TNHH Đầu Tư Phát Triển Cuộc Sống +84 28 3977 8269 / +8428 3601 6797 Email:... more

Bộ khuếch đại công suất (Power Amplifier) là gì? Tìm hiểu về ứng dụng, những loại bộ khuếch đại công suất hiện đang có trên thị trường
Thông tin liên hệ
Công ty TNHH Đầu Tư Phát Triển Cuộc Sống
+84 28 3977 8269 / +8428 3601 6797
Email: sales@lidinco.com Website: htts://lidinco.com/
487 Cộng Hòa, phường 15, quận Tân Bình, TP. Hồ Chí Minh

- by Duy Lại
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- Sound, Audio Amplifiers, Power Amplifiers
- by Santiago Prieto
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- Power Amplifiers, Amplificadores

Amplifiers are commonly used electronic devices that increase the amplitude of an input signal. Amplifiers are used in many areas of electronics, including audio, data acquisition, and communication. This paper will discuss Class AB and B... more

- by Eric Sims
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- Electrical Engineering, Electronics, Audio Amplifiers, Low Distortion
- by Santiago Prieto
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- Power Amplifiers, Amplificadores

Dalam dunia elektronika, transistor memiliki peranan yang sangat penting sebagai alat
semikonduktor yang dipakai sebagai penguat. Bagian yang diperkuat adalah amplitudo dari sinyal. Penguat
daya yang akan diuji adalah kelas A, B, dan C. Proses perancangan rangkaian penguat yang akan dibuat
diperkirakan terlebih dahulu nilai-nilai komponen dan berapa jumlah komponen yang dipakai. Dari hasil
perancanga tersebut maka akan didapatkan sebuah acuan dalam pembuatan trainer. Setiap pengukuran yang
dilakukan akan dibandingkan antara parameter input dan parameter output masing-masing rangkaian
penguat. Yang mempengaruhi penguatan pada rangkaian penguat ada pada kombinasi dari komponen yang
digunakan misalnya nilai dari tahanan yang dipakai pada masing-masing titik pengukuran yang dilakukan.
Hasil pengujian menunjukkan nilai penguatan rata-rata pada rangkaian penguat kelas A rata-ratanya sebesar
26,6 kali tegangan masukan yang diberikan. Sedangkan pada penguat kelas B sebesar 1,5 kali. Dari hasil
perhitungan yang digunakan ada perbedaan pada pengukuran langsung dengan datasheet transistor yang
digunakan sebesar 60, setelah dilakukan pengukuran penguatan yang digunakan sebesar 8 kali. Pengujian
pada rangkaian yang sudah dibuat masih dihasilkan nilai error. Nilai error dapat terjadi karena beberapa hal
yaitu perbedaan nilai komponen yang dipakai pada rangkaian sebenarnya karena nilai komponen ada yang
tidak sama sesuai dengan perhitungan secara teori. Sehingga mempengaruhi adanya perbedaan nilai
pengukuran dan secara teori.

- by ST3 Telkom Purwokerto and +1
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- Software Components, Parameter estimation, Error Analysis, Intercultural communication(Components)

One of the most vulnerable global challenges that face the world is relying heavily on oil, natural gas, and coal for energy needs, besides increasing the dependence on fossil fuels. These fuels draw on lots of resources that will eventually diminish, making them too expensive or environmentally damaging to recover. Wastes are convertible to useful energy forms like polluted air or even sound waves. This research's primary investigation is to present using the sound waves that come out from the factories' machines' and converting it to electricity. The produced electricity will return to the machine and operate it without using an external source of electricity. The experiment was done using a power amplifier, capacitors, electric condenser microphone, potentiometer, and ohms. The experiment results fulfilled the design requirements as cost reduction, high efficiency and quality, and long endurance. The prototype output of electricity was 16V, and its efficiency was 15%. One of the most vulnerable global challenges that face the world is relying heavily on oil, natural gas, and coal for energy needs, besides increasing the dependence on fossil fuels. These fuels draw on lots of resources that will eventually diminish, making them too expensive or environmentally damaging to recover. Wastes are convertible to useful energy forms like polluted air or even sound waves. This research's primary investigation is to present the idea of using the sound waves that comes out from the factories' machines and converting them to electricity. The produced electricity will return to the machine and operate it without using an external source of electricity. The experiment was done using a power amplifier, capacitors, electric condenser microphone, potentiometer, and ohms. The experiment results fulfilled the design requirements as cost reduction, high efficiency and quality, and long endurance. The prototype output of electricity was 16V, and its efficiency was 15%.

- by Donia Hamam and +1
- •
- Environmental Science, Renewable Energy, Electronics, Energy

In this work, the theoretical behavior has studied widely which they present/display the devices
known like “line Array”, obtaining a series of design conclusions raising a practical
implementation and its later verification. With the intention of carrying out the study of the real
behavior of this type of systems, “line array” of four elements on the basis of the obtained
conclusions, on which a series of real tests is made, characterizing its acoustic behavior,
determining the sonorous field that has been constructed they generate and its pattern of
directivity in the different configurations.

- by Juan Miguel Navarro
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- Loudspeakers, Power Amplifiers, Electroacustics

In this paper, signal compression due to the nonlinearity of RF Amplifier in Quadratuer-Phase Shift Keying (QPSK) is examined for a specific power amplifier (PA) nonlinearity model, by using simulation. One of the most important aspects in the future radio communication services is the use of spectrally efficient modulation schemes to increase the system capacity. Modulation schemes such as QPSK with an appropriate pulse shaping is spectrally efficient, but this type of modulation presents variations in amplitude and phase due to filtering. A matched Root Raised Cosine (RRC) filtering and an ideal Additive White Gaussian Noise (AWGN) channel are used in baseband equivalent simulation model, in order to isolate the effects in Solid Stat power Amplifier.

- by SDIWC Organization
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- Computer Science, Information Technology, Power Amplifiers, Nonlinearity

This paper presents the progress of monolithic technology for microwave application, focusing on gallium nitride technology advances in the realization of integrated power amplifiers. Three design examples, developed for microwave backhaul radios, are shown. The first design is a 7 GHz Doherty developed with a research foundry, while the second and the third are a 7 GHz Doherty and a 7-15 GHz dual-band combined power amplifiers, both based on a commercial foundry process. The employed architectures, the main design steps and the pros and cons of using gallium nitride technology are highlighted. The measured performance demonstrates the potentialities of the employed technology, and the progress in the accuracy, reliability and performance of the process.

The design of frequency-tunable amplifiers is investigated and the tradeoff between linearity, efficiency and tunability is revealed. Several tunable amplifiers using various varactor diode topologies as tunable devices are designed by using loadpull techniques and their performances are compared. The amplifier using anti-series distortion-free varactor stack topology achieves 38% power added efficiency and it may be tuned from 1.74 to 2.36 GHz (about 35% tunable range). The amplifier using anti-series/anti-parallel topology is tunable from 1.74 to 2.14 GHz (about 23% tunable range) and provides 42% power added efficiency. It is demonstrated that tunable amplifiers using distortion-free varactor stack topologies provide better power added efficiency than the tunable amplifiers using reverse biased varactor diodes and their linearity is similar to that of a conventional amplifier. These amplifiers may facilitate the realization of frequency agile radio frequency transceiver front-ends and may replace several parallel connected amplifiers used in conventional multimode radios.

This contribution introduces a novel broadband power amplifier design, operating in the frequency band ranging from 1.5 GHz to 3 GHz which cover the mainstream applications running in L and S bands. Both matching and biasing networks are synthesized by using microstrip transmission lines. In order to provide a wide bandwidth, two broadband matching techniques are deployed for this purpose, the first technique is an approximate transformation of a previously designed lumped elements matching networks into microstrip matching circuits, and the second technique is a binomial multi-sections quarter wave impedance transformer. The proposed work is based on ATF-13786 active device. The simulation results depict a maximum power gain of 16.40 dB with an excellent input and output matching across 1.5 GHz ~ 3 GHz. At 2.2 GHz, the introduced BPA achieves a saturated output power of 16.26 dBm with a PAE of 21.74%, and a 1-dB compression point of 4.5 dBm input power level. The whole circuitry is...

2. Single-Stage Amplifiers

- by ngu ngue
- •
- Power Amplifiers

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.

A fully differential rail-rail input stage and class AB output stage with and without common-mode feedback circuit are proposed. There are at least 4 schematics to be proposed. The first schematic is CMOS rail-rail input stage and class AB output stage without common-mode feedback (CMFB) circuit. The second schematic is CMOS rail-rail input stage and class AB output stage with CMFB circuit. For low voltage operation, the tail current sources of the first and second schematics are removed. As a consequence, there is no voltage drop between drain and source terminals of the current source, and bulk-source voltage effect of the input transistor is removed.

- by キッチポントリペッチ， and +1
- •
- Audio Amplifiers, Power Amplifiers

This paper presents the design theory of conventional single-ended LNA and differential LNA based on CMOS technology. The design concepts give an useful indication to the design trade-offs associated with NF, gain and impedance matching. Four LNA's have been designed using technological design rules of TSMC 0.18-µm CMOS technology and this work mainly proposed for IEEE 802.11a applications. With 1.8V supply voltage, the proposed LNA's achieve a gain higher than 19dB, a noise figure less than 4dB and impedance matching less than-10dB at 5GHz frequency. The goal of this paper is to highlight the efficient LNA architecture for achieving simultaneous gain, noise and input matching at low supply voltage. The performance of all LNA's are analysed and compared using Agilent's Advanced Design System Electronic Design Automation tools.

The trade-off between efficiency and tunability has been revealed in frequency-tunable amplifiers. Several tunable amplifiers have been designed using various varactor diode topologies and their performances are compared. Simulation results demonstrate that the tunable amplifiers using anti-series distortion-free varactor stack (DFVS) topologies provide superior tunability and power added efficiency (PAE) than those using conventional varactor diode topologies. A tunable amplifier is designed that can tune from 1.74-to-2.36 GHz and provide 42% PAE. This range of tunability is sufficient to accommodate DCS-1800, PCS-1900, DECT and UMTS standards, and thus it may help to reduce the complexity of multimode and reconfigurable radios.

High power wideband amplifiers are demanded in many application areas, such as software defined radio, electronic warfare (EM), instrumentation systems, etc. The quality of the wireless communication system requires demand for compact, low-cost, and low power transportable transceivers has augmented dramatically. Among the transceiver’s building blocks is that the power electronic equipment. Thus, there's a desire for low-priced power electronic equipment. It’s necessary to think about the MOSFET gate-to-drain capacitance for achieving the class-E Zero Voltage Switching conditions. As a result, the ability output capability and therefore the power conversion potency are full of the MOSFET gate-to-drain capacitance. The waveform obtained from Analog to Digital simulations and circuit experiments showed the quantitative agreements with the theoretical predictions.

- by RAGUL M KUMAR and +1
- •
- Engineering, Electrical Engineering, Electronic Engineering, Mechanical Engineering

Digital predistortion of a baseband signal is a well-known method of power amplifier (PA) linearization used to reduce adjacent channel interference (ACI) in a non constant envelope modulation system. This paper discusses the application of adaptive digital baseband predistortion linearization to radio frequency (RF) power amplifiers (PAs) that exhibit memory effects. This technique is a highly cost- effective way to linearize Power amplifiers (PAs), but most existing architectures assume that the PA has a memoryless nonlinearity. For wider bandwidth applications such as wideband code-division multiple access (WCDMA) or wideband orthogonal frequency-division multiplexing (W- OFDM), PA memory effects can no longer be ignored. In this paper a new technique for adaptation of digital predistorter that considers memory effects in power amplifiers is proposed. This method is a combination of two techniques, memory polynomial predistortion and slope-dependent method. This new technique is validated by using a 1.9 GHz 60 W LDMOS power amplifier and various signals such as 2- carrier CDMA and 3-carrier CDMA.

El objetivo de esta práctica es que con los conocimientos adquiridos de todo el curso sobre telecomunicaciones y las practicas realizadas anteriormente, construiremos un amplificador de RF que sea capaz de amplificar la señal del emisor de RF, donde este se encuentre en un ancho de banda el cual sea de uso libre y de alguna cierta potencia de transmisión (en la banda de 151MHz).

The objective of this research was to design a 2.4 GHz class AB Power Amplifier (PA), with 0.18um Semiconductor Manufacturing International Corporation (SMIC) CMOS technology by using Cadence software, for health care applications. The ultimate goal for such application is to minimize the trade-offs between performance and cost, and between performance and low power consumption design. This paper introduces the design of a 2.4GHz class AB power amplifier which consists of two stage amplifiers. This power amplifier can transmit 10dBm output power to a 50Ω load. The power added efficiency is 7.5% at 1dB compression point and the power gain is 10dB, the total power consumption is 0.135W. The performance of the power amplifier meets the specification requirements of the desired.

- by International Journal of Biomedical Engineering and Science (IJBES) and +1
- •
- Power Amplifiers

This paper presents an analytical framework to calculate the average symbol-error rate (SER) of uncoded orthogonal frequency-division multiplexing (OFDM) systems in realistic scenarios impaired by transmitter nonlinearity and frequency-selective fading channels. The results are applicable to cyclically extended OFDM signals characterized by a high number of carriers, which can be modeled as complex Gaussian processes. To avoid intercarrier interference, we also assume that the symbol duration is shorter than the channel coherence time. We derive analytical SER results in Rayleigh and Rice frequency-selective fading channels, for both the nonlinear amplification and the ideal predistortion case. Simulations results demonstrate the validity of the analytical results.

- by Paolo Banelli
- •
- OFDM, Ofdm Systems, Power Amplifiers

The objective of this research was to design a 2.4 GHz class AB Power Amplifier (PA), with 0.18um Semiconductor Manufacturing International Corporation (SMIC) CMOS technology by using Cadence software, for health care applications. The ultimate goal for such application is to minimize the trade-offs between performance and cost, and between performance and low power consumption design. This paper introduces the design of a 2.4GHz class D power amplifier which consists of two stage amplifiers. This power amplifier can transmit 15dBm output power to a 50Ω load. The power added efficiency was 50% and the total power consumption was 90.4 mW. The performance of the power amplifier meets the specification requirements of the desired.

The distortion of transmitters is an impediment of the improvement of frequency use. It causes the restriction of the actual transmission rate due to deterioration of modulation accuracy in the channel band, and gives interference to radios about the radio that uses neighboring frequencies outside the channel band. In this paper, LINC with excellent theoretical linearity but the low power efficiency in low power range and EER with excellent power efficiency and higher linearity than linear amplifiers in high power but lower distortion in low power are combined as the measures, and it is operated as EER in a high power range and LINC in a low power range. Then, issues of efficiency of LINC and dynamic range of EER are solved, and it is possible to balance excellent linearity and wide dynamic range. Furthermore, band limiting of the envelope amplifier in ad-dition to balance linearity and dynamic rage becomes possible because it combines this proposal and the band limiting enve-lope amplifier of EER. As a result, the feasibility of LINC systems and EER systems for which realization in broadband or high PAPR modulation systems improves by this proposal.

- by Takahiko Kishi
- •
- RF and Microwave Systems, Power Amplifiers
- by Amlan Jyoti Bhagawati
- •
- Electrical Engineering, Biomedical Engineering, Image Processing, EEG

High Efficiency power amplifier for cellular base station is in high demand as 5G infrastructure will include more cells in order to cover denser areas of transport. High Efficiency power amplifiers are demanded, as they serve a key bottle neck in each cell. high efficiency power amplifier is introduced with peak power of 70W in a range of 2Ghz-3.6Ghz bandwidth with 50-62% efficiency. The design makes harmonic engineering till the 3 rd harmonic at the output and at the input of the power amplifier, in order to reach the highest efficiency. The amplifier is tested with a 40Mhz LTE signal with DPD implementation. .

- by Meir Alon
- •
- Power Electronics, Power Amplifiers

This invention relates to vacuum tube amplifers, and involves a method and apaparatus by means of which the amplifying power of vacuum tube amplifers are equalized, so that these tubes can replace each other, particularly in a balanced... more

- by Mihajlo Pupin
- •
- Power Electronics, Power Amplifiers, Amplifier

— Since its introduction, compressed sampling (CS) has found use in various applications ranging from image restoration, radar and sensing to channel and system identification. Recently in the radio frequency (RF) power amplifier (PA) design and linearization communities, there have been many attempts to utilize the CS technique to enable the development of efficient wireless transmitters. This paper provides a brief review of the use of CS in PA and transmitter linearization. Mainly two approaches are discussed: the use of CS to recover amplitude-distorted signals, and the use of CS to reduce the complexity of the digital predistorters. Experimental results obtained using an envelope tracking (ET) PA prototype show the potential and value of the CS technique in developing efficient predistorters at a low computational cost.

- by Oualid Hammi
- •
- Linearization, Power Amplifiers, Digital Predistorter, Digital Predistortion

In this paper we present a reconfigurable Class-E Power Amplifier (PA) whose operation frequency covers all uplink bands of GSM standard. We describe the circuit design strategy to reconfigure PA operation frequency maximizing the efficiency. Two dies, manufactured using CMOS and MEMS technologies, are assembled through bondwires in a SiP fashion. Prototypes deliver 20dBm output power with 38% and 26% drain efficiencies at lower and upper bands, respectively. MEMS technological issues degrading performance are also discussed.

- by R. Brama
- •
- Materials Science, MEMS, Manufacturing, Modeling

The main objective of this study is to investigate common power amplifier classes which are class A, B, AB, C and etc. In the first section, types of power amplifiers have been presented and important parameters that affect the efficiency of power amplifiers have been discussed. The circuit topologies of class A, B, AB, C, and E have been given and the working principle of these amplifiers has been discussed. As an experiment, different circuit configurations of class AB amplifier have been constructed and the results have been given. According to the experiment results, the conclusion part was provided about the power amplifiers.

- by Oguzhan Dogan
- •
- Power Electronics, Class E power amplifier, Power Amplifiers

The main aim of this study is to design efficient inductive power transfer (IPT) system which includes series L-C resonant circuit and load network. In order to achieve high efficiency, class-D amplifier, which includes two switching devices (MOSFET), was implemented and the MOSFETs are driven by 0.5 duty cycle PWM signals which are generated by IR2110 MOSFET driver. The inductive link was realized by primary and secondary coils which consists of copper wires and in the experiment, 70.58% transmission efficiency was obtained. The input and output power are 2.55 W and 1.8 W respectively. Also the switching performance of driver in class-D amplifier has been observed and analysed.

- by Oguzhan Dogan
- •
- Power Amplifiers, Inductive Power Transfer, Wireless Power Transfer