Adrian Kotelba

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This paper considers the compensation of linear and nonlinear distortions which are present in RF part of envelope tracking (ET) am,plifier. In particular, we consider the compensation of magnitude and phase responses of analog filters, amplifier nonlinearity, and possible time misalignment between signals in RF and envelope branches. We propose a new(More)
This paper studies the analytical relationship between the average transmitted and received energies under several adaptive transmitter power control methods, including water filling, truncated power inversion, and downlink beamforming. The study is applicable to many fading channel scenarios, including frequency-nonselective, frequency-selective, and(More)
A nonideal radio transmitter both distorts the desired signal and generates spectral regrowth causing interference to adjacent channels. Predistortion techniques can be used to minimize these effects. The joint effect of different types of nonidealities is not straightforward to analyze and has not yet been studied in detail in the literature. In this(More)
This paper considers the compensation of time misalignment between RF and envelope signals of envelope tracking (ET) amplifier. In particular, we propose methods to compensate the time misalignment and compare them to a previously presented method. Our simulation results indicate that the proposed methods give very accurate timing estimates. In the presence(More)