Search Results - "Borges Carvalho, Nuno"

Quadrature Amplitude Backscatter Modulator for Passive Wireless Sensors in IoT Applications by Correia, Ricardo, Boaventura, Alirio, Borges Carvalho, Nuno

“…Fully passive wireless networks are a key-enabling technologies for the internet of things. Backscatter radios are a hypothesis to design these passive…”
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Continuously Power Delivering for Passive Backscatter Wireless Sensor Networks by Correia, Ricardo, Borges Carvalho, Nuno, Kawasaki, Shigeo

“…Nowadays wireless sensor networks (WSNs) depend on the battery duration and there is a lot of interest in creating a passive sensor network scheme in the area…”
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The Design of a High-Performance Multisine RFID Reader by Soares Boaventura, Alirio J., Borges Carvalho, Nuno

“…We report on the design of an enhanced EPC Gen2/ISO18000-6C-compliant UHF RFID reader with waveform optimization capability. By properly designing the powering…”
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Wireless Power Transmission: R&D Activities Within Europe by Borges Carvalho, Nuno, Georgiadis, Apostolos, Costanzo, Alessandra, Rogier, Hendrik, Collado, Ana, García, José Angel, Lucyszyn, Stepan, Mezzanotte, Paolo, Kracek, Jan, Masotti, Diego, Boaventura, Alírio J. Soares, de las Nieves Ruíz Lavin, Maria, Pinuela, Manuel, Yates, David C., Mitcheson, Paul D., Mazanek, Milos, Pankrac, Vitezslav

“…Wireless power transmission (WPT) is an emerging technology that is gaining increased visibility in recent years. Efficient WPT circuits, systems and…”
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A Broadband Almost-Digital RF Transmitter With an Efficient Power Amplifier by Wonhoon Jang, Cordeiro, Rui, Oliveira, Arnaldo, Borges Carvalho, Nuno

“…A new architecture of an almost-digital RF transmitter is proposed. It consists of easy-to-have functional modules. Among the modules, a broadband Doherty…”
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Spatial Power Combining of Multi-Sine Signals for Wireless Power Transmission Applications by Boaventura, Alirio J. Soares, Collado, Ana, Georgiadis, Apostolos, Borges Carvalho, Nuno

“…This paper presents two transmitter architectures for wireless power transmission (WPT) applications. These architectures aim at transmitting high…”
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Agile All-Digital DPD Feedback Loop by Prata, Andre, Santos, Jorge C., Oliveira, Arnaldo S. R., Borges Carvalho, Nuno

“…This paper presents an original agile all-digital feedback loop receiver system for power amplifier (PA) linearization using digital predistortion (DPD). The…”
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Resonant Electrical Coupling: Circuit Model and First Experimental Results by Dias Fernandes, Ricardo, Matos, Joao Nuno, Borges Carvalho, Nuno

“…In this paper, the feasibility of resonant electrical coupling as a wireless power transfer technique is studied. A detailed comparison between this technique…”
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When Backscatter Communication Meets Vehicular Networks: Boosting Crosswalk Awareness by Pereira, Felisberto, Sampaio, Hugo, Chaves, Ricardo, Correia, Ricardo, Luis, Miguel, Sargento, Susana, Jordao, Marina, Almeida, Luis, Senna, Carlos, Oliveira, Arnaldo S. R., Borges Carvalho, Nuno

“…The research of safety applications in vehicular networks has been a popular research topic in an effort to reduce the number of road victims. Advances on…”
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A Convex Optimization Approach for the Design of Supergain Electrically Small Antenna and Rectenna Arrays Comprising Parasitic Reactively Loaded Elements by Georgiadis, Apostolos, Carvalho, Nuno Borges

“…A convex optimization formulation is provided for antenna arrays comprising reactively loaded parasitic elements. The objective function consists of maximizing…”
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An OOK Chirp Spread Spectrum Backscatter Communication System for Wireless Power Transfer Applications by Belo, Daniel, Carvalho, Nuno Borges

“…In this work, a general-purpose wireless energy receiving unit with improved backscatter (BS) communications capabilities assisted by far-field wireless power…”
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Millimeter-Wave Hybrid RF-DC Converter Based on a GaAs Chip for IoT-WPT Applications by Matos, Diogo, Correia, Ricardo, Carvalho, Nuno Borges

“…This letter presents an mm-wave hybrid RF-dc converter based on a gallium arsenide (GaAs) chip for wireless power transmission (WPT) applications. Both chip…”
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Nonlinear Dynamic RF System Characterization: Envelope Intermodulation Distortion Profiles-A Noise Power Ratio-Based Approach by Figueiredo, Ricardo, Carvalho, Nuno Borges, Piacibello, Anna, Camarchia, Vittorio

“…As radio frequency (RF) applications occupy larger bandwidths, nonlinear dynamics become nonnegligible. This work presents a theoretical framework capable of…”
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A Selective, Tracking, and Power Adaptive Far-Field Wireless Power Transfer System by Belo, Daniel, Ribeiro, Diogo C., Pinho, Pedro, Borges Carvalho, Nuno

“…This paper proposes a selective, tracking, and power adaptive far-field wireless power transfer (WPT) system that may be integrated into passive wireless…”
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Harmonic RFID Temperature Sensor Design for Harsh Environments by Silveira, Tagleorge Marques, Pinho, Pedro, Carvalho, Nuno Borges

“…This letter presents a new passive sensor for temperature measurements based on a harmonic radio-frequency identification (RFID) tag that uses the temperature…”
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Bandwidth Analysis of RF-DC Converters Under Multisine Excitation by Pan, Ning, Belo, Daniel, Rajabi, Mohammad, Schreurs, Dominique, Carvalho, Nuno Borges, Pollin, Sofie

“…The use of multisine signals to improve the efficiency of wireless power transfer (WPT) for low average received power was proposed recently. Several…”
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Challenges in Resource-Constrained IoT Devices: Energy and Communication as Critical Success Factors for Future IoT Deployment by Pereira, Felisberto, Correia, Ricardo, Pinho, Pedro, Lopes, Sérgio I, Carvalho, Nuno Borges

“…Internet of Things (IoT) has been developing to become a free exchange of useful information between multiple real-world devices. Already spread all over the…”
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Four-PAM Modulation of Ambient FM Backscattering for Spectrally Efficient Low-Power Applications by Daskalakis, Spyridon Nektarios, Correia, Ricardo, Goussetis, George, Tentzeris, Manos M., Carvalho, Nuno Borges, Georgiadis, Apostolos

“…Ambient backscatter uses radio frequency signals available in the environment (e.g., radio broadcasting, television, or mobile telephony) to transmit data…”
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Quasioptics for increasing the beam efficiency of wireless power transfer systems by Pereira, Ricardo A. M., Carvalho, Nuno Borges

“…The highest beam efficiency in a wireless power transfer (WPT) system that uses focusing components was 51%, using a ≈ 3 m diameter reflector for a transfer…”
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Millimeter-Wave BiCMOS Backscatter Modulator for 5 G-IoT Applications by Matos, Diogo, da Cruz Jordao, Marina Daniela, Correia, Ricardo, Carvalho, Nuno Borges

“…In this letter, the authors present the first millimeter-wave (mm-wave) high-order backscatter modulator, based on a BiCMOS technology for 5G/Internet of…”
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