In this paper a two-phase supply modulator suitable for envelope tracking power amplifier is presented. The designed supply modulator has the linear assisted switching architecture. Two-phase architecture is used in order to reduce the output switching ripples. The proposed architecture uses hysteretic control instead of pulse width modulation (PWM) which significantly reduces the circuit compl...

QIN, JIFENG. A Low Noise, High Efficiency Envelope Modulator Structure for EDGE Polar Modulation. (Under the direction of Dr. Alex Q. Huang). Dynamic supply of power amplifiers in wireless transmitters can overcome the linearity-efficiency tradeoff issue in power amplifiers design, and envelope modulator is the key block in the dynamic supply system, low noise and high efficiency implementation...

in scpc-dama satellite networks, the baseband rrc pulse shaping is utilized to reduce the bandwidth and inter symbol interference (isi). but the variation in carrier's envelope, which expands the spectrum and ultimately increases the bandwidth, causes isi and quadrature channel crosstalk (qcc). the goal of this paper is to introduce a method to shape baseband rrc pulses, in order to make a near...

H. J. De Los Santos et al., Radio Systems Engineering, DOI 10.1007/978-3-319-07326-2_2, © The Authors 2015 Abstract In this chapter, we present a number of topics surrounding modulation and demodulation. We begin by introducing system-level block diagrams of AM and FM/PM modulators and demodulators, and explaining their respective principles of operation. In particular, under the topic of AM Mo...

These experiments explored the effect of relative modulator phase on the detection of a three-component modulator applied to a 4,000-Hz sinusoidal carrier with a level of 70 dB SPL. The central modulator component had a frequency of 50 Hz, and the two other components had frequencies of 50+/-5, 10, 25, 40, or 45 Hz. Thus, the modulator waveform was always periodic. Each modulator component had ...

A constant-envelope, continuous phase modulation architecture is presented in which a sigma-delta modulator is combined with an open-loop modulator. Compared to existing architectures, Σ∆ based open-loop modulation can be implemented with minimal analog circuitry. The architecture is demonstrated with a discrete implementation performing frequency modulation at a carrier frequency of 120 MHz. B...

 It is crucial for the spectral-efficient communication systems, associated with the sophisticated digital modulation formats to be able to handle the RF signal containing a probably very large variation of the envelope magnitude. The aim of this work is to build an optimal transmitter linearization architecture suitable to achieve a highly linear transmission and to be highly power efficient....

This brief provides a tutorial on designing high efficiency envelope-tracking supply modulator with recent techniques. Design challenges for 5G communication applications are given. Detailed techniques covering topology derivation, multi-level and fast-speed switching converter design considerations, voltage step-up –down function implementations, linear amplifier bandwidth improvements measure...