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Variable domain transformation for linear PAC analysis of mixed-signal systems
This paper describes a method to perform linear AC analysis on mixed-signal systems which appear strongly nonlinear in the voltage domain but are linear in other variable domains. Common circuits like phase/delay-locked loops and duty-cycle correctors fall into this category, since they are designed to be linear with respect to phases, delays, and duty-cycles of the input and output clocks, respectively. The method uses variable domain translators to change the variables to which the AC perturbation is applied and from which the AC response is measured. By utilizing the efficient periodic AC (PAC) analysis available in commercial RF simulators, the circuitâs linear transfer function in the desired variable domain can be characterized without relying on extensive transient simulations. Furthermore, the variable domain translators enable the circuits to be macromodeled as weakly-nonlinear systems in the chosen domain and then converted to voltage-domain models, instead of being modeled as strongly-nonlinear systems directly
Discrete-Time Chaotic-Map Truly Random Number Generators: Design, Implementation, and Variability Analysis of the Zigzag Map
In this paper, we introduce a novel discrete chaotic map named zigzag map
that demonstrates excellent chaotic behaviors and can be utilized in Truly
Random Number Generators (TRNGs). We comprehensively investigate the map and
explore its critical chaotic characteristics and parameters. We further present
two circuit implementations for the zigzag map based on the switched current
technique as well as the current-mode affine interpolation of the breakpoints.
In practice, implementation variations can deteriorate the quality of the
output sequence as a result of variation of the chaotic map parameters. In
order to quantify the impact of variations on the map performance, we model the
variations using a combination of theoretical analysis and Monte-Carlo
simulations on the circuits. We demonstrate that even in the presence of the
map variations, a TRNG based on the zigzag map passes all of the NIST 800-22
statistical randomness tests using simple post processing of the output data.Comment: To appear in Analog Integrated Circuits and Signal Processing (ALOG
The nonlinear class-E amplifier: a case study of harmonic balance applied to switched circuits
Nonlinear switched circuits are usually analyzed in
the time domain. The use of frequency-domain methods to
analyze the steady-state of switched circuits is usually restricted
to linear circuits and, although Volterra series approaches are
applied to the distortion of nonlinear switched circuits, the use
of harmonic balance (HB) methods in nonlinear switched
circuits seems to be marginal if not discarded. In this paper, we
analyze the nonlinear class-E amplifier with an ideal switch by
means of the HB method. We show how the switching function
may be carefully chosen to improve the accuracy of the solution.
When the circuit achieves actual class-E operation, the method
converges better and is more accurate than classical timedomain
methods. We conclude that the HB method is an
alternative to time-domain methods that can be used to analyze
the class-E amplifier in its expected operation mode.Postprint (published version
Optimization Of 5.7 Ghz Class E Power Amplifier For The Application Of Envelope Elimination And Restoration
Tez (YĂŒksek Lisans) -- Ä°stanbul Teknik Ăniversitesi, Fen Bilimleri EnstitĂŒsĂŒ, 2007Thesis (M.Sc.) -- Ä°stanbul Technical University, Institute of Science and Technology, 2007Rekabetin yoÄun olduÄu gĂŒnĂŒmĂŒzde tasarımcılar hafif, boyutları daha kĂŒĂ§ĂŒk ve dĂŒĆĂŒk gĂŒĂ§le çalıĆan yĂŒksek performanslı ĂŒrĂŒn geliĆtirmenin yollarını aramaktadırlar. RF alıcı uygulamalarında gĂŒĂ§ kuvvetlendiricileri en fazla gĂŒĂ§ sarfiyatının olduÄu bölĂŒmdĂŒr. Kablosuz iletiĆim sistemlerinde gĂŒĂ§ kĂŒvvetlendiricisi verimi maliyeti direkt olarak etkilemektedir. Teorik olarak %100 verim elde edilebilen E-sınıfı gĂŒĂ§ kuvvetlendiricileri transistorların açık/kapalı durum geçiĆlerinde gĂŒĂ§ sarfiyatını minimize edebilmektedir. Ayrıca çıkÄ±Ć gerilimi kaynak gerilimi ile doÄrusal deÄiĆmektedir. Bu çalıĆmada E sınıfı gĂŒĂ§ kuvvetlendiricilerinin tasarım metodları ele alınmıĆtır. 5.7 GHz de çalıĆan birinde toplu devre elemanları, diÄerinde transmisyon hattı elemanları kullanımÄ±Ć E sınıfı gĂŒĂ§ kuvvetlendiricileri tasarlanmıĆtır. Her iki devrede de %50 gĂŒĂ§ ekli verim (GEV) ve 500mW çıkÄ±Ć gĂŒcĂŒ elde edilmiĆtir. Sinyaldeki bozulmayı azaltmak için baĆvurulan doÄrusallaĆtırma yöntemi Zarf Yoketme ve Tekrar OluĆturma metodudur. E sınıfı kuvvetlendiricinin Zarf Yoketme ve Tekrar OluĆturma yöntemi kullanılarak doÄrusallaĆtırılmasıyla IMD bileĆenlerinde 7.5 dB azalmÄ±Ć olup seviyesi gerçek iĆaretin 20dB altındadır.In todayâs competitive, manufactures and product developers are seeking ways to build high performance devices that are lighter in weight, smaller in size and operating at lower power. In transceiver applications one module is responsible for a large portion of the power consumption - the power amplifier. The efficiency of the power amplifier has a direct impact on the cost of the wireless communication system. The class-E amplifier has a maximum theoretical efficiency of 100%. Class E power amplifiers have the ability to minimize power loss during on/off transitions of the transistor. Also, the output voltage varies linearly with the supply voltage. This thesis describes the design and the linearization methodology of the Class E amplifiers. Two class-E amplifiers operating at 5.7 GHz are presented. One of them is a lumped elements based circuit and the other is a transmission lines based circuit. Both circuit show good performance with 50% PAE and have 500mW output power. Envelope elimination and restoration is the linearization method chosen to achieve reduction of signal distortion. Linearization Class E PA using EER system provides an additional 7.5 dB reduction in intermodulation distortion products, achieving a minimum distortion level of 20 dB below the fundamental signals.YĂŒksek LisansM.Sc
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