Linearization of RF power amplifiers with memoryless baseband predistortion method

Download

index.pdf

Date

2011

Author

Kolcuoğlu, Turusan

Metadata

Show full item record

Item Usage Stats

132
views

41
downloads

In modern wireless communication systems, advanced modulation techniques are used to support more users by handling high data rates and to increase the utilization efficiency of the limited RF spectrum. These techniques are sensitive to the nonlinear distortions due to their high peak to average power ratios. Main source of nonlinear distortion in transmitter topologies are power amplifiers that determine the overall efficiency and linearity of the transmitter. To increase linearity without sacrificing efficiency, power amplifier linearization techniques may be a choice. Baseband predistortion technique is known to be one of the optimum methods due to its relatively low complexity and its convenience for adaptation. In this thesis, diff erent memoryless baseband signal predistortion methods are investigated and analyzed by simulations. Look-Up Table(LUT) and Polynomial approaches are compared and LUT approach is found to be better in performance. Parameters, like indexing, training sequences and training duration are evaluated. An open loop testbench is built with a real amplifier and a different LUT predistortion method that is based on amplifier modeling is off ered. It is evaluated by using two tone test and adjacent channel power suppression with 8PSK data. Also, some Look-Up Table parameters are re-investigated with the proposed method. The performances of the proposed method in di erent amplifier classes are observed. Along with these studies, a list of prerequisites for design of a predistortion system is determined.

Subject Keywords

Power amplifiers.

URI

http://etd.lib.metu.edu.tr/upload/12613213/index.pdf
https://hdl.handle.net/11511/20559

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Improving the efficiency of microwave power amplifiers without linearity degradation using load and bias tuning in a new configuration Ronaghzadeh, Amin; Demir, Şimşek; Department of Electrical and Electronics Engineering (2013) Advanced digital modulation schemes used in the wireless applications, result in the modulated RF signals with high peak to average power ratio which requires linear amplification. On the other hand, the demand for a longer talk time with less battery volume and weight, especially in hand-held radio units, necessitate more power efficient methods to be utilized in power amplifier design. But improved linearity and efficiency have always been contradicting requirements demanding innovative power ampliﬁer and...
Development of a tuner topology for multiharmonic matching and implementation on tunable dual band power amplifier design Kılıç, Hasan Hüseyin; Demir, Şimşek; Department of Electrical and Electronics Engineering (2018) In this thesis work, the effect of multi-harmonic load matching on improving the efficiency of power amplifiers is investigated. Techniques of efficient power amplifier design are discussed and analyzed in terms of multi-harmonic matching. Several circuit topologies are evaluated for multi-harmonic matching by discussing the advantages and the limitations. Specifically, a detailed multi-harmonic analysis of the triple stub topology is presented. The already-known single frequency impedance matching capabili...
Highly Integrated 3 V Supply Electronics for Electromagnetic Energy Harvesters With Minimum 0.4 V-peak Input Ulusan, Hasan; Zorlu, Ozge; Muhtaroglu, Ali; Külah, Haluk (2017-07-01) This paper presents a self-powered interface enabling battery-like operation with a regulated 3 V output from ac signals as low as 0.4 V-peak, generated by electromagnetic energy harvesters under low frequency vibrations. As the first stage of the 180 nm standard CMOS circuit, harvested signal is rectified through an ac/dc doubler with active diodes powered internally by a passive ac/dc quadrupler. The voltage is boosted in the second stage through a low voltage charge pump stimulated by an on-chip ring osc...
Performance comparison of passive series R and shunt R-C damped LCL filter for grid-connected inverters Temiz, Hakan; Demirok, Erhan; Keysan, Ozan; Turkay, Ali; Cetinkaya, Burak (2019-07-01) LCL filters are widely used in distributed power-generation systems to attenuate high-frequency harmonics caused by pulse-width modulation switching of grid-connected inverters. A resonance occurs due to the series-connected reactive components. In order to damp resonance effects, active and passive damping methods are used. Lower switching frequencies are typically preferred to decrease switching power losses with high-power applications. Thus, control bandwidth of the system is limited and implementation ...
An experimental study on Power Amplifier linearisation by artificial neural networks Yapay Sinir Aǧlari ile Güç Yükselteç Doǧrusalląstirma Amaçli Deneysel Bir Çalisma Yesil, Soner; Kolagasioglu, Ahmet Ertugrul; Yılmaz, Ali Özgür (2018-07-05) This paper represents an experimental study on the linearisation of Power Amplifiers especially on high output power regions by utilizing an artificial neural network structure and open-loop training method. For the same in-band output power, 9dB EVM and 6dB ACLR improvement has been observed on hardware by feeding the proposed digital predistortion signal (DPD) to the PA under test.

Citation Formats

T. Kolcuoğlu, “Linearization of RF power amplifiers with memoryless baseband predistortion method,” M.S. - Master of Science, Middle East Technical University, 2011.