Publications by authors named "Guy Torfs"

Aside from a clinical interest in electroencephalography (EEG) measurements of real-time data with a high temporal resolution, there is a demand for acquisition systems that are operable outside the laboratory environment. In this study, we designed a wearable and low-power EEG system for multichannel EEG acquisition beyond the lab doors. Around-the-ear cEEGrid electrodes are used to capture 8 biopotential channels which are amplified by low-power precision instrumentation amplifiers and passed on to an analog-to-digital converter (ADC).

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To address the rising demand for high-speed wireless data links, communication systems operating at frequencies beyond [Formula: see text] are being targeted. A key enabling technology in the development of these wireless systems is the phased antenna array. Yet, the design and implementation of such steerable antenna arrays at frequencies over [Formula: see text] comes with a multitude of challenges.

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An advanced transmit remote opto-antenna unit is proposed that accomplishes impedance matching between a photodetector and a low-profile antenna in a specified frequency bandwidth, without requiring an area-consuming matching network. This results in a highly compact design, which also avoids the losses and spurious radiation by such an electrically large matching circuit. Instead, the photodetector is almost directly connected to the antenna, which is designed as a conjugate load, such that the extracted and radiated power are optimized.

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Next-generation wireless communication will require increasingly faster data links. To achieve those higher data rates, the shift towards mmWave frequencies and smaller cell sizes will play a major role. Radio-over-Fiber has been proposed as a possible architecture to allow for this shift but is nowadays typically implemented digitally, as CPRI (Common Public Radio Interface).

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In this article, we study human electromagnetic exposure to the radiation of an ultra dense network of nodes integrated in a floor denoted as ATTO-cell floor, or ATTO-floor. ATTO-cells are a prospective 5 G wireless networking technology, in which humans are exposed by several interfering sources. To numerically estimate this exposure we propose a statistical approach based on a set of finite difference time domain simulations.

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A BiCMOS chip-based real-time intensity modulation/direct detection spatial division multiplexing system is experimentally demonstrated for both optical interconnects. 100 Gbps/λ/core electrical duobinary (EDB) transmission over 1 km 7-core multicore fiber (MCF) is carried out, achieving KP4 forward error correction (FEC) limit (BER < 2E-4). Using optical dispersion compensation, 7 × 100 Gbps/λ/core transmission of both non-return-to-zero (NRZ) and EDB signals over 10 km MCF transmission is achieved with BER lower than 7% overhead hard-decision FEC limit (BER < 3.

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For the first time, a personal exposimeter (PEX) for 60 GHz radiation measurements is presented. The PEX is designed based on numerical simulations and both on-body and on-phantom calibration measurements to determine the antenna aperture and measurement uncertainty of the PEX. The measurement uncertainty of the PEX is quantified in terms of 50 and 95% prediction intervals of its response.

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In the future, wireless radiofrequency (RF) telecommunications networks will provide users with gigabit-per-second data rates. Therefore, these networks are evolving toward hybrid networks, which will include commonly used macro- and microcells in combination with local ultra-high density access networks consisting of so-called attocells. The use of attocells requires a proper compliance assessment of exposure to RF electromagnetic radiation.

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This paper presents an ultra-low power SiGe BiCMOS IC for driving a 10 channel electro-absorption modulator (EAM) array at 113Gb/s for wavelength division multiplexing passive optical network (WDM-PON) applications. With an output swing of 2.5V(pp), the EAM driver array consumes only 2.

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A functional demonstration of bit-interleaving TDM downstream protocol for passive optical networks (Bi-PON) is reported. The proposed protocol presents a significant reduction in dynamic power consumption in the customer premise equipment over the conventional TDM protocol. It allows to select the relevant bits of all aggregated incoming data immediately after clock and data recovery (CDR) and, hence, allows subsequent hardware to run at much lower user rate.

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