Power supply for a radio transmitter with modulated supply voltage

Trescastro-López, Eva María; Oliver, J. A.; Cobos, J.A.; Cezon, J.; Arevalo, F.

doi:10.1109/apec.2004.1295839

Cited by 60 publications

(42 citation statements)

References 8 publications

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“…The multi-phase buck topology [23] was conceived to be used as Voltage Regulator Modules (VRMs) for supplying microprocessors due to the high efficiency and high bandwidth achieved [24]- [25]. In addition, this topology is widely used as envelope amplifier when applying the envelope tracking (ET) technique [26]- [34]. These applications have some similarities with the high-side converter of the proposed VLC transmitter architecture: the output voltage level is low, the demanding bandwidth is very high, very low output voltage ripple is mandatory and in the case of both ET and VLC, a certain voltage reference must be tracked.…”

Section: B Proposed Architecturementioning

confidence: 99%

Performance evaluation of a VLC transmitter based on the split of the power

Rodríguez

Aller

Lamar

et al. 2018

2018 IEEE Applied Power Electronics Conference and Exposition (APEC)

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Abstract-Visible Light Communication (VLC) has gained relevance during last years. It consists in using High-Brightness LEDs (HB-LEDs) both for lighting and for transmitting information changing the light intensity rapidly. However, there are some bottlenecks that are slowing down the deployment of this technology. One of the most important problems is that the HB-LED drivers proposed for addressing high data rates in VLC achieve poor power efficiency. Since these HB-LED drivers must be able to reproduce fast current waveforms, the use of Linear Power Amplifiers (LPAs) has been adopted, which clearly damage the power efficiency of HB-LED lighting. In order to alleviate this problem, a HB-LED driver made up of two DC-DC power converters is presented in this work. One of them is responsible for performing the communication functionality by operating at high switching frequency (10 MHz), whereas the second one fulfills the illumination functionality by ensuring a certain biasing point. The split of the power allows to minimize the power delivered by the fast-response DC-DC power converter. Thus, the efficiency can be maximized for scenarios with changing conditions (i.e., mobile transmitter and/or receiver, presence of mobile obstacles, etc.). In this sense, how the lighting level and the communication signal power affect both the power efficiency and the communication efficiency is deeply analyzed. The implemented prototype achieves an overall efficiency around 90%. In addition, the proposed VLC transmitter is able to reproduce a wide range of digital modulation schemes, including Orthogonal Frequency Division Multiplexing (OFDM).

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Section: B Proposed Architecturementioning

confidence: 99%

Performance evaluation of a VLC transmitter based on the split of the power

Rodríguez

Aller

Lamar

et al. 2018

2018 IEEE Applied Power Electronics Conference and Exposition (APEC)

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“…ENVELOPER AMPLIFIER Due to high bandwidth requirements, conventional solutions for tracking power supplies [8][9][10] are not energy efficient. The envelope amplifier that will be used consists of a multilevel converter and a linear regulator in series, [11].…”

Section: (T) = Arctg Gg) A(t) = Jiw+owmentioning

confidence: 99%

High efficiency power amplifier for high frequency radio transmitters

Vasić

García

Oliver

et al. 2010

2010 Twenty-Fifth Annual IEEE Applied Power Electronics Conference and Exposition (APEC)

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Abstract-Modern transmitters usually have to amplify and transmit complex communication signals with simultaneous envelope and phase modulation. Due to this property of the transmitted signal, linear power amplifiers (class A, B or AB) are usually employed as a solution for the power amplifier stage. These amplifiers have high linearity, but suffer from low efficiency when the transmitted signal has high peak-to-average power ratio. The Kahn envelope elimination and restoration (EER) technique is used to enhance efficiency of RF transmitters, by combining highly efficient, nonlinear RF amplifier (class D or E) with a highly efficient envelope amplifier in order to obtain linear and highly efficient RF amplifier. This paper presents solutions for the power supply that acts as the envelope amplifier and class E amplifier that is used as a nonlinear amplifier. The envelope amplifier is implemented as a multilevel converter in series with a linear regulator and can provide up to 100 W of peak power and reproduce sine wave of 2 MHz, while the implemented class E amplifier operates at 120 MHz with an efficiency near to 90%. The envelope amplifier and class E amplifier have been integrated in order to implement the Kahn's technique transmitter and series of experiments have been conducted in order to characterize the implemented transmitter.

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“…In the state of the art, several solutions for the envelope amplifier can be found, such as a simple buck converter (class S modulator) in [3][4][5], multiphase buck converter in [6], threelevel converter in [7] or linear assisted switching amplifier [8,9]. These solutions do not exceed the bandwidth of few hundred kHz and the output power is from the range of mW up to several tens of watts.…”

Section: Introductionmentioning

confidence: 99%