The Design of Concurrent Dual Band Envelope Tracking Power Amplifier for Basestations

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (91 download)

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Book Synopsis The Design of Concurrent Dual Band Envelope Tracking Power Amplifier for Basestations by : Yiqiao Lin

Download or read book The Design of Concurrent Dual Band Envelope Tracking Power Amplifier for Basestations written by Yiqiao Lin and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The linearity and efficiency of a transmitting system is largely determined by its last stage component: the Power Amplifier (PA). In the past century, engineers and scientists have pioneered various architectures to optimize the PA performance - most notably the linearity and efficiency, as these quantities directly correspond to signal integrity and cost, respectively. In this dissertation, the design, implementation, and measurement results of a concurrent dual-band envelope tracking (ET) PA system is detailed. The dual-band PA system incorporates a new envelope tracking (ET) methodology which relaxes the large bandwidth requirement typically placed on supply modulators for dual-band applications, resulting in significant efficiency improvement. Afterwards, the PA linearity optimized through the use of a new, highly stable, and scalable digital predistortion (DPD) scheme, viable for both constant supply as well as modulated supply (ET) dual-band PAs. The developed ET and multi-dimentional DPD system methodologies are then verified using a 10W peak gallium-nitride (GaN) ET PA operating with a dual-band input based on LTE and WCDMA signals, with center frequencies spaced by 310 MHz. The testbed is based on a Altera FPGA Stratix IV and two Analog Device mixed signal DPD boards. The proposed method provides a performance improvement as high as 17 dB in terms of normalized mean square error (NMSE) and 4.6 dB in terms of adjacent channel power ratio (ACPR) in comparison to the conventional dual-band memory polynomial method including ET.

Concurrent Multi-band Envelope Tracking Power Amplifiers for Emerging Wireless Communications

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ISBN 13 :
Total Pages : 112 pages
Book Rating : 4.:/5 (96 download)

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Book Synopsis Concurrent Multi-band Envelope Tracking Power Amplifiers for Emerging Wireless Communications by : Hassan Sarbishaei

Download or read book Concurrent Multi-band Envelope Tracking Power Amplifiers for Emerging Wireless Communications written by Hassan Sarbishaei and published by . This book was released on 2014 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: Emerging wireless communication is shifting toward data-centric broadband services, resulting in employment of sophisticated and spectrum efficient modulation and access techniques. This yields communication signals with large peak-to-average power ratios (PAPR) and stringent linearity requirements. For example, future wireless communication standard, such as long term evolution advanced (LTE-A) require adoption of carrier aggregation techniques to improve their effective modulation bandwidth. The carrier aggregation technique for LTE-A incorporates multiple carriers over a wide frequency range to create a wider bandwidth of up to 100MHz. This will require future power amplifiers (PAs) and transmitters to efficiently amplify concurrent multi-band signals with large PAPR, while maintaining good linearity. Different back-off efficiency enhancement techniques are available, such as envelope tracking (ET) and Doherty. ET has gained a lot of attention recently as it can be applied to both base station and mobile transmitters. Unfortunately, few publications have investigated concurrent multi-band amplification using ET PAs, mainly due to the limited bandwidth of the envelope amplifier. In this thesis, a novel approach to enable concurrent amplification of multi-band signals using a single ET PA will be presented. This thesis begins by studying the sources of nonlinearities in single-band and dual-band PAs. Based on the analysis, a design methodology is proposed to reduce the sources of memory effects in single-band and dual-band PAs from the circuit design stage and improve their linearizability. Using the proposed design methodology, a 45W GaN PA was designed. The PA was linearized using easy to implement, memoryless digital pre-distortion (DPD) with 8 and 28 coefficients when driven with single-band and dual-band signals, respectively. This analysis and design methodology will enable the design of PAs with reduced memory effects, which can be linearized using simple, power efficient linearization techniques, such as lookup table or memoryless polynomial DPD. Note that the power dissipation of the linearization engine becomes crucial as we move toward smaller base station cells, such as femto- and pico-cells, where complicated DPD models cannot be implemented due to their significant power overhead. This analysis is also very important when implementing a multi-band ET PA system, where the sources of memory effects in the PA itself are minimized through the proposed design methodology. Next, the principle of concurrent dual-band ET operation using the low frequency component (LFC) of the envelope of the dual-band signal is presented. The proposed dual-band ET PA modulates the drain voltage of the PA using the LFC of the envelope of the dual-band signal. This will enable concurrent dual-band operation of the ET PA without posing extra bandwidth requirements on the envelope amplifier. A detailed efficiency and linearity analysis of the dual-band ET PA is also presented. Furthermore, a new dual-band DPD model with supply dependency is proposed in this thesis, capable of capturing and compensating for the sources of distortion in the dual-band ET PA. To the best of our knowledge, concurrent dual-band operation of ET PAs using the LFC of the envelope of the dual-band signal is presented for the first time in the literature. The proposed dual-band ET operation is validated using the measurement results of two GaN ET PA prototypes. Lastly, the principle of concurrent dual-band ET operation is extended to multi-band signals using the LFC of the envelope of the multi-band signal. The proposed multi-band ET operation is validated using the measurement results of a tri-band ET PA. To the best of our knowledge, this is the first reported tri-band ET PA in literature. The tri-band ET PA is linearized using a new tri-band DPD model with supply dependency.

Envelope Amplifier Design for Wireless Base-station Power Amplifiers

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ISBN 13 : 9781124324258
Total Pages : 128 pages
Book Rating : 4.3/5 (242 download)

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Book Synopsis Envelope Amplifier Design for Wireless Base-station Power Amplifiers by : Chin Hsia

Download or read book Envelope Amplifier Design for Wireless Base-station Power Amplifiers written by Chin Hsia and published by . This book was released on 2010 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: In order to deliver high data rates, modern wireless communication systems transmit complex modulated signals with high peak-to-average ratio, which demands wide bandwidth and stringent linearity performance for power amplifiers. To satisfy spectral mask regulations and achieve adequate error vector magnitude, power amplifiers typically operate at 6 to 10 dB back-off from the maximum output power, leading to low efficiency. To overcome the low efficiency problem, the envelope tracking power amplifier architecture has been proposed for this type of application due to its feature of high efficiency over a wide power range. The overall efficiency of an envelope tracking system relies not only on performance of the RF power amplifier but also on that of an envelope amplifier that provides a dynamically varying power supply voltage. This dissertation focuses on envelope amplifier design for efficiency enhancement of envelope tracking power amplifiers. First, the envelope tracking power amplifier architecture is analyzed, and the efficiency of a RF transistor in the envelope tracking technique is described. Then envelope amplifier behavior is investigated and a general purpose simulator is developed for analyzing and designing an envelope amplifier. Power loss and efficiency of the envelope amplifier is analyzed and compared with experimental results. The design of envelope amplifiers for high voltage (> 30 V) envelope tracking applications is described. A high voltage envelope amplifier is designed, implemented and verified. The overall envelope tracking system employing a GaN-HEMT RF transistor is demonstrated. Finally, a new architecture is developed for the efficiency enhancement of envelope amplifiers, using a digitally assisted controller design. Digital control is utilized to mitigate delay in the control loop inside the envelope amplifier, leading to lower overall power dissipation. A novel envelope amplifier architecture with dual-switcher stages based on the digitally-assisted control strategy is proposed, designed and implemented. The strategy is demonstrated to improve the efficiency of envelope amplifier as well as the system overall efficiency. The resulting performance of envelope tracking system employing a GaAs high voltage HBT with a single carrier W-CDMA input demonstrated state-of-the-art efficiency with good linearity performance.

Envelope Tracking Power Amplifiers for Wireless Communications

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Publisher : Artech House
ISBN 13 : 1608077845
Total Pages : 363 pages
Book Rating : 4.6/5 (8 download)

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Book Synopsis Envelope Tracking Power Amplifiers for Wireless Communications by : Zhancang Wang

Download or read book Envelope Tracking Power Amplifiers for Wireless Communications written by Zhancang Wang and published by Artech House. This book was released on 2014-06-01 with total page 363 pages. Available in PDF, EPUB and Kindle. Book excerpt: Envelope tracking technology is seen as the most promising efficiency enhancement technology for RF power amplifiers for 4G and beyond wireless communications. More and more organizations are investing and researching on this topic with huge potential in academic and commercial areas. This is the first book on the market to offer complete introduction, theory, and design considerations on envelope tracking for wireless communications. This resource presents you with a full introduction to the subject and covers underlying theory and practical design considerations.

Envelope Amplifier for Broadband Base-station Envelope Tracking Power Amplifier

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Publisher :
ISBN 13 : 9781124727844
Total Pages : 125 pages
Book Rating : 4.7/5 (278 download)

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Book Synopsis Envelope Amplifier for Broadband Base-station Envelope Tracking Power Amplifier by : Qiuyao Zhu

Download or read book Envelope Amplifier for Broadband Base-station Envelope Tracking Power Amplifier written by Qiuyao Zhu and published by . This book was released on 2011 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt: Envelope tracking (ET), which is a dynamic supply control technology to realize high efficiency power amplifiers, is a promising approach for base-station transmitters of the future. The envelope amplifier (EA) in ET systems provides a non-constant modulated power supply to the RF transistor. It is challenging to design so that it is both broadband and high efficiency, while meeting the stringent linearity requirements for high peak-to-average ratio signals in modern wireless communication systems. This thesis focuses on EA design and implementation for efficiency enhancement of ET systems with broadband envelope input signals. First, the ET system architecture is analyzed, and the efficiencies of RF transistors and envelope amplifiers are described. Secondly, the principles of the EA operation are investigated, and each circuit stage is carefully designed for broadband signals. Then, an EA model, including the RF transistor load, is developed in PSpice, and many simulations are described in order to better analyze and design the broadband EA for high efficiency. After the design, a broadband EA is implemented on a PCB board. The testing with constant resistive loads is carried out to verify the function and measure the efficiencies of 5 MHz WCDMA and 20 MHz LTE-A downlink envelope signals. Finally, tests on the whole ET system are performed, and the overall drain and power added efficiencies are tabulated. For this broadband envelope amplifier, the efficiency for a 5 MHz WCDMA input signal is above 75%, and for 20 MHz LTE-A, it works robustly with an efficiency of 62%.

Dual-band Power Amplifier for Wireless Communication Base Stations

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ISBN 13 :
Total Pages : 57 pages
Book Rating : 4.:/5 (835 download)

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Book Synopsis Dual-band Power Amplifier for Wireless Communication Base Stations by : Xin Fu

Download or read book Dual-band Power Amplifier for Wireless Communication Base Stations written by Xin Fu and published by . This book was released on 2012 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: In wireless communication systems, multiple standards have been implemented to meet the past and present demands of different applications. This proliferation of wireless standards, operating over multiple frequency bands, has increased the demand for radio frequency (RF) components, and consequently power amplifiers (PA) to operate over multiple frequency bands. In this research work, a systematic approach for the synthesis of a novel dual-band matching network is proposed and applied for effective design of PA capable of maintaining high power efficiency at two arbitrary widely spaced frequencies. The proposed dual-band matching network incorporates two different stages. The first one aims at transforming the targeted two complex impedances, at the two operating frequencies, to a real one. The second stage is a dual-band filter that ensures the matching of the former real impedance to the termination impedance to 50 Ohm. Furthermore, an additional transmission line is incorporated between the two previously mentioned stages to adjust the impedances at the second and third harmonics without altering the impedances seen at the fundamental frequencies. Although simple, the harmonic termination control is very effective in enhancing the efficiency of RF transistors, especially when exploiting the Class J design space. The proposed dual-band matching network synthesis methodology was applied to design a dual-band power amplifier using a packaged 45 W gallium nitride (GaN) transistor. The power amplifier prototype maintained a peak power efficiency of about 68% at the two operating frequencies, namely 800 MHz and 1.9 GHz. In addition, a Volterra based digital predistortion technique has been successfully applied to linearize the PA response around the two operating frequencies. In fact, when driven with multi-carrier wideband code division multiple access (WCDMA) and long term evolution (LTE) signals, the linearized amplifier maintained an adjacent channel power ratio (ACPR) of about 50 dBc and 46 dBc, respectively.

Recent Technical Developments in Energy-Efficient 5G Mobile Cells

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Publisher : MDPI
ISBN 13 : 3039362127
Total Pages : 292 pages
Book Rating : 4.0/5 (393 download)

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Book Synopsis Recent Technical Developments in Energy-Efficient 5G Mobile Cells by : Raed A. Abd-Alhameed

Download or read book Recent Technical Developments in Energy-Efficient 5G Mobile Cells written by Raed A. Abd-Alhameed and published by MDPI. This book was released on 2020-06-17 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses the true innovation in engineering design that may be promoted by blending together models and methodologies from different disciplines, and, in this book, the target was exactly to follow this approach to deliver a new disruptive architecture to deliver these next-generation mobile small cell technologies. According to this design philosophy, the work within this book resides in the intersection of engineering paradigms that includes “cooperation”, “network coding”, and “smart energy-aware frontends”. These technologies will not only be considered as individual building blocks, but re-engineered according to an inter-design approach resulting in the enabler for energy efficient femtocell-like services on the move. The book aims to narrow the gap between the current networking technologies and the foreseen requirements that are targeted at the future development of the 5G mobile and wireless communications networks in terms of the higher networking capacity, the ability to support more users, the lower cost per bit, the enhanced energy efficiency, and adaptability to new services and devices (for example, smart cities, and the Internet of things (IoT)).

High Efficiency Wideband Envelope Tracking Power Amplifier for Next-generation Wireless Communications

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Publisher :
ISBN 13 : 9781124856230
Total Pages : 109 pages
Book Rating : 4.8/5 (562 download)

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Book Synopsis High Efficiency Wideband Envelope Tracking Power Amplifier for Next-generation Wireless Communications by : Myoungbo Kwak

Download or read book High Efficiency Wideband Envelope Tracking Power Amplifier for Next-generation Wireless Communications written by Myoungbo Kwak and published by . This book was released on 2011 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt: The latest generation of smart devices deployed in cellular networks has created explosive growth in network data traffic, and the increasing demand for broadband services with higher data rates, require higher peak to average power ratio (PAPR) with wider bandwidth. One of the challenges in the conventional power amplifiers (PAs) with fixed supply voltage, is the degraded efficiency and generated heats at a large back-off to meet tight linearity requirements. This dissertation presents high efficiency wideband envelope tracking power amplifiers for 2.1 GHz micro base-stations and 2.5 GHz wireless mobile applications. By superimposing the envelope signal at the drain such that the RF amplifier operates consistently closer to saturation, the overall efficiency is improved and the generated heat is reduced dramatically. In the first part of the dissertation, a high performance BiCMOS DMOS monolithic envelope amplifier for micro-base station power amplifiers is presented. Due to the low breakdown voltage of the CMOS transistors, the high voltage envelope amplifier has been implemented with discrete components with high voltage process. Compared to these discrete solutions, an integrated circuits implementation for the envelope amplifier brings many benefits. The design of monolithic envelope amplifiers for high voltage (VDD = 15 V) envelope tracking applications, and the design techniques to solve the reliability issues with thin gate oxide is described. The overall envelope tracking system employing a GaN-HEMT RF transistor, and fully integrated high voltage envelope amplifier with a 0.35[mu]m BiCMOS DMOS process, is demonstrated. In the second part, a high-efficiency wideband envelope tracking power amplifier for mobile LTE applications will be presented. The CMOS envelope amplifier with hybrid linear and switcher is designed in a 150 nm CMOS process. The envelope amplifier employs direct sensing of the linear stage current to reduce the propagation delay in the switcher. The strategy is demonstrated to improve the efficiency of the complete envelope tracking power amplifier system. The resulting performance of envelope tracking system employing a GaAs HBT-based RF PA with a 5 MHz LTE signal input demonstrated state-of-the-art efficiency while meet the linearity requirement.

Design and Implementation of an Envelope Tracking Power Amplifier Using Switched Amplifiers and Slow Envelopes

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (84 download)

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Book Synopsis Design and Implementation of an Envelope Tracking Power Amplifier Using Switched Amplifiers and Slow Envelopes by : Pedro Pablo Vizarreta Paz

Download or read book Design and Implementation of an Envelope Tracking Power Amplifier Using Switched Amplifiers and Slow Envelopes written by Pedro Pablo Vizarreta Paz and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Analysis and Design of Envelope Tracking Power Amplifier

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Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (955 download)

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Book Synopsis Analysis and Design of Envelope Tracking Power Amplifier by : Amir Javan Khoshkholgh

Download or read book Analysis and Design of Envelope Tracking Power Amplifier written by Amir Javan Khoshkholgh and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Concurrent Dual-band Doherty Power Amplifiers for Carrier Aggregation

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Publisher :
ISBN 13 :
Total Pages : 71 pages
Book Rating : 4.:/5 (1 download)

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Book Synopsis Concurrent Dual-band Doherty Power Amplifiers for Carrier Aggregation by : Mingming Liu

Download or read book Concurrent Dual-band Doherty Power Amplifiers for Carrier Aggregation written by Mingming Liu and published by . This book was released on 2017 with total page 71 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carrier aggregation is the main feature of the Long Term Evolution advanced (LTE-A) standard to increase the spectral efficiency and communication bandwidth. It calls for wireless transmitters to be multi-band and multi-standard to meet the demands of various deployment scenarios. In addition, these transmit radios must efficiently amplify signals characterized with a high peak-to-average power ratio (PAPR), which is caused by advanced modulation schemes. These two factors highlight the need for the multi-band Doherty power amplifier (DPA), which allows the transmitter remain in high efficiency at back-off power levels and maintain that high efficiency over multiple frequency bands. In this work, a novel output combining network is presented for the dual-band DPA design with extended fractional bandwidth for carrier aggregated signals. The proposed output combiner employs a modified Pi-shape network, which enables the absorption of output capacitances from both the main and peaking devices and eliminates the need for phase offset lines which are major sources of bandwidth limitation in the existing multiband DPAs. In addition to performing the impedance inversion, the proposed combiner incorporates the biasing feeds and presents small low-frequency impedances to both the main and peaking transistors. The inclusion of the bias feeds and small low low-frequency impedance feature improves the linearizability of the DPA when stimulated with concurrent dual-band modulated signals. Lastly, by using the gain contour at the back-off power level, the non-linear AM-AM response caused by the varying input capacitance of the main transistor is mitigated. The proposed dual-band output power combiner and the back-off gain contour technique were applied to design of a dual-band two-way Doherty PA using the commercialized 25W Gallium Nitride (GaN) transistor. Measurement of the two-way DPA shows a gain of 7.5- 9.5 dB at 2.05 - 2.3 GHz and 9 - 11 dB at 3.2 - 3.62 GHz. The efficiency at 6 dB back off is greater than 49% and 47% across the two frequency bands. The linearizability of the dual-band DPA is validated using various carrier aggregated signals. The PA exhibits linear behaviour when driven by up to 80 MHz intra-band carrier aggregated signal and 20 MHz concurrent dual-band signal after DPD. Additionally, carrier aggregated signals usually lead to a PAPR value between 8-10 dB. The efficiency of classic two-way DPA deteriorates when dealing with such signals. To cope with the efficiency deterioration, a three-way DPA was designed. Simulations of the three-way DPA show that the gain is greater than 9 dB within the two frequency bands, 2.05 - 2.32 GHz and 3.35 - 3.65 GHz. The efficiency at 10-dB back-off is greater than 40% in the two frequency bands.

Design of a Power Amplifier and Envelope Amplifier for a Multi-band Multi-standard Envelope Tracking System

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ISBN 13 :
Total Pages : 61 pages
Book Rating : 4.:/5 (835 download)

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Book Synopsis Design of a Power Amplifier and Envelope Amplifier for a Multi-band Multi-standard Envelope Tracking System by : Yushi Hu

Download or read book Design of a Power Amplifier and Envelope Amplifier for a Multi-band Multi-standard Envelope Tracking System written by Yushi Hu and published by . This book was released on 2012 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents the design of a Power Amplifier (PA) and envelope amplifier for an Envelope Tracking (ET) system that is aimed at meeting emerging radio standards in terms of power efficiency and linearity. The class J mode of operation, as well as the efficiency and power contours from load pull was exploited to develop an adequate procedure for the design of a broadband and high efficiency radio frequency PA. An in-depth study has also been conducted for a hybrid envelope amplifier topology in order to optimize it for power efficiency through proper setting of its switching stage supply. Two separate proof of concept prototypes of the PA and envelop amplifier were designed, fabricated and tested. The PA designed was able to achieve an average drain efficiency of 73.6%, average output power of 45.89dBm, and an average gain of 18dB between 650MHz and 1.050GHz (48% bandwidth). The envelope amplifier achieved close to 74.6% efficiency for a 5MHz bandwidth LTE signal envelope with 6.4dB peak to average power ratio.

Multi-Band Outphasing Power Amplifier Design for Mobile and Base Stations

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Publisher :
ISBN 13 :
Total Pages : 92 pages
Book Rating : 4.:/5 (897 download)

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Book Synopsis Multi-Band Outphasing Power Amplifier Design for Mobile and Base Stations by : Omid Talebi Amiri

Download or read book Multi-Band Outphasing Power Amplifier Design for Mobile and Base Stations written by Omid Talebi Amiri and published by . This book was released on 2014 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:

High Efficiency Broadband Envelope-Tracking Power Amplifiers

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Publisher :
ISBN 13 : 9781303195266
Total Pages : 168 pages
Book Rating : 4.1/5 (952 download)

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Book Synopsis High Efficiency Broadband Envelope-Tracking Power Amplifiers by : Jonmei Johana Yan

Download or read book High Efficiency Broadband Envelope-Tracking Power Amplifiers written by Jonmei Johana Yan and published by . This book was released on 2013 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: In order to meet the increasing demand for higher data rates while maximizing spectral efficiency, modern wireless communication systems transmit complex non-constant envelope modulation signals with high peak-to-average ratio (PAPR). As a result, conventional power amplifiers must be operated in back-off, leading to a significant efficiency reduction. Various power amplifier architectures (i.e. Doherty, outphasing, and envelope tracking) have been demonstrated to achieve high efficiency for these high PAPR signals. Unlike the other architectures, the envelope tracking power amplifier (ETPA) makes an excellent candidate for multi-band multi-frequency use, while maintaining high efficiency for high PAPR and under average power back-off, as it is fundamentally immune to changes in the frequency of the carrier; it depends only on the envelope of the RF signal. This dissertation focuses on the design of envelope tracking power amplifiers for enabling broadband wireless communication systems. First, a test-bench for evaluating broadband ETPAs is described. A calibration routine, acting as a pre-equalizer, is used to achieve a flat linear response over the entire instantaneous bandwidth of the system, resulting in less than 1% EVM for a 40 MHz LTE signal. Performances of envelope tracking power amplifiers on this test-bench at various frequencies from UHF to millimeter-wave are evaluated, and record efficiencies are demonstrated. Next, this dissertation describes how in under practical usage, the power transmitted fluctuates as a function of the load demands over time. The long-term efficiency of the ETPA is evaluated using Monte-Carlo simulations based on a projected time-varying power profile. Compared to a Doherty PA with the same peak efficiency, the ETPA can provide more than 1.4x reduction in overall energy consumed. The ETPA thus provides significant opportunities for system energy savings under realistic operation. Thirdly, to accommodate the wide range of carrier frequencies required for numerous emerging wireless systems, a multi-octave RFPA based on a compact GaN stacked IC with RC feedback is designed, fabricated, and evaluated. Multi-octave ET operation was demonstrated from 500 to 1750 MHz with >25% efficiency. Compared to its constant drain voltage counterpart, >2x improvement in RFPA efficiency is observed in ET. Lastly, while the ETPA provides advantages such as broad carrier bandwidths and high efficiency under back-off operation, one of the main challenges in ETPA design lies in accommodating wide modulation bandwidths. Adaptive de-troughing, a digital signal processing approach for extending the modulation bandwidth capability of an existing dynamic power supply, is described and evaluated. Measurements demonstrated the ability to extend ET operation to 20 MHz LTE signals. In addition, ~5-6% modulator efficiency enhancement was measured when comparing "standard" to "adaptive" de-troughing supply waveforms.

RF Power Amplifiers

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Publisher : John Wiley & Sons
ISBN 13 : 1118844343
Total Pages : 685 pages
Book Rating : 4.1/5 (188 download)

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Book Synopsis RF Power Amplifiers by : Marian K. Kazimierczuk

Download or read book RF Power Amplifiers written by Marian K. Kazimierczuk and published by John Wiley & Sons. This book was released on 2014-11-26 with total page 685 pages. Available in PDF, EPUB and Kindle. Book excerpt: This second edition of the highly acclaimed RF Power Amplifiers has been thoroughly revised and expanded to reflect the latest challenges associated with power transmitters used in communications systems. With more rigorous treatment of many concepts, the new edition includes a unique combination of class-tested analysis and industry-proven design techniques. Radio frequency (RF) power amplifiers are the fundamental building blocks used in a vast variety of wireless communication circuits, radio and TV broadcasting transmitters, radars, wireless energy transfer, and industrial processes. Through a combination of theory and practice, RF Power Amplifiers, Second Edition provides a solid understanding of the key concepts, the principle of operation, synthesis, analysis, and design of RF power amplifiers. This extensive update boasts: up to date end of chapter summaries; review questions and problems; an expansion on key concepts; new examples related to real-world applications illustrating key concepts and brand new chapters covering ‘hot topics’ such as RF LC oscillators and dynamic power supplies. Carefully edited for superior readability, this work remains an essential reference for research & development staff and design engineers. Senior level undergraduate and graduate electrical engineering students will also find it an invaluable resource with its practical examples & summaries, review questions and end of chapter problems. Key features: • A fully revised solutions manual is now hosted on a companion website alongside new simulations. • Extended treatment of a broad range of topologies of RF power amplifiers. • In-depth treatment of state-of-the art of modern transmitters and a new chapter on oscillators. • Includes problem-solving methodology, step-by-step derivations and closed-form design equations with illustrations.

Linearization of Concurrent Dual-band Power Amplifier Using Digital Predistortion

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (91 download)

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Book Synopsis Linearization of Concurrent Dual-band Power Amplifier Using Digital Predistortion by : Naveen Naraharisetti

Download or read book Linearization of Concurrent Dual-band Power Amplifier Using Digital Predistortion written by Naveen Naraharisetti and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: With the current demand for higher data-rate transmissions, complex envelop techniques like wideband code division multiple access (WCDMA) and orthogonal frequency division multiplexing (OFDM) techniques are employed because of their high spectral efficiency. However these modulated schemes which feature non-constant envelop signals with high peak to average power ratio (PAPR) also impose strict linearity requirements on the PAs. A digital predistortion is used to linearize the PA for its robustness and easy implementation on an FPGA. The complexity of the DPD design is alleviated using widely spaced carriers and frequency selective technique.

RF Power Amplifiers for Wireless Communications

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Publisher : Artech House Publishers
ISBN 13 : 9781596930186
Total Pages : 456 pages
Book Rating : 4.9/5 (31 download)

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Book Synopsis RF Power Amplifiers for Wireless Communications by : Steve C. Cripps

Download or read book RF Power Amplifiers for Wireless Communications written by Steve C. Cripps and published by Artech House Publishers. This book was released on 2006-01-01 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: This extensively revised edition offers a comprehensive, practical, up-to-date understanding of how to tackle a power amplifier design with confidence and quickly determine the cause of malfunctioning hardware.