Searched for: subject%3A%22Clocks%22
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Naranjo, D. (author), Parisi, Laura (author), Jónsson, Sigurjón (author), Jousset, Philippe (author), Werthmüller, D. (author), Weemstra, C. (author)
The timing of the recordings of ocean-bottom seismometers (OBSs) is critical for accurate earthquake location and Earth model studies. GNSS signals, however, cannot reach OBSs deployed at the ocean bottom. This prevents their clocks from being synchronized with a known reference time. To overcome this, we developed OCloC, a Python package that...
abstract 2023
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Rajan, R.T. (author), Van der Veen, A.J. (author)
Synchronization and localization are critical challenges for the coherent functioning of a wireless network of mobile nodes. In this paper, a novel joint non-linear range and affine time model is presented based on two way time stamp exchanges, extending an existing affine time-range model. For a pair of nodes, a closed form pairwise least...
conference paper 2013
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Abel, Felix (author), Sundaramoorthy, P.P. (author), Rajan, R.T. (author)
Recently, an increase in distributed space systems and a rise in number of nodes in such systems is observed in numerous space applications, for example space-based interferometry. Such applications pose stringent demands on time synchronization which can be challenging to achieve for satellite networks that lack an absolute time reference...
conference paper 2022
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Kotti, Sofia Eirini (author), Heusdens, R. (author), Hendriks, R.C. (author)
The use of wireless acoustic sensor networks (WASNs) has received increased attention over the last decade. The advantages of WASNs over stand-alone multi-microphone devices are that the microphone array is not anymore limited by the dimensions of a single device, and that microphones can be placed at arbitrary locations. One of the...
conference paper 2020
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Xie, Y. (author), Janssen, G.J.M. (author), van der Veen, A.J. (author)
A clock synchronization scheme is crucial for obtaining accuracy in time-based positioning systems. Existing clock synchronization schemes are mostly based on a simplified linear clock model, which unfortunately have a poor long-term synchronization accuracy. Assuming a two-way time transfer protocol, we propose a novel clock synchronization...
conference paper 2016
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Karmakar, S. (author), Gonen, B. (author), Sebastiano, F. (author), Van Veldhoven, Robert (author), Makinwa, K.A.A. (author)
Micro-power ADCs with high linearity and dynamic range (DR) are required in several applications, such as smart sensors, biomedical imaging, and portable instrumentation. Since the signals of interest are then often small (tens of μν) and slow (<1kHz BW), such ADCs should also exhibit low offset and flicker noise. Noise-shaping SAR [1] and...
conference paper 2018
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Kazaz, T. (author), Coutino, Mario (author), Janssen, G.J.M. (author), Leus, G.J.T. (author), van der Veen, A.J. (author)
Synchronization and ranging in internet of things (IoT) networks are challenging due to the narrowband nature of signals used for communication between IoT nodes. Recently, several estimators for range estimation using phase difference of arrival (PDoA) measurements of narrowband signals have been proposed. However, these estimators are based...
conference paper 2019
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Dirkx, D. (author)
Measurements of the motion of natural (and artificial) bodies in the solar system provide key input on their interior structre and properties. Currently, the most accurate measurements of solar system dynamics are performed using radiometric tracking systems on planetary missions, providing range measurement with an accuracy in the order of 1 m....
doctoral thesis 2015
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Chepuri, S.P. (author)
In today's society, we are flooded with massive volumes of data in the order of a billion gigabytes on a daily basis from pervasive sensors. It is becoming increasingly challenging to locally store and transport the acquired data to a central location for signal/data processing (i.e., for inference). To alleviate these problems, it is evident...
doctoral thesis 2016
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Gao, Z. (author)
Reducing power consumption is becoming increasingly important for the sustainability of the communication industry because it is expected to consume a significant portion of the global electricity in the face of the exponentially increasing demands on the volume and rate of data transmission. As the scope narrows to the individual wireless...
doctoral thesis 2023
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Van Kasteren, J. (author)
More eloquent alternatives to the harsh tones of the oldfashioned alarm-clock bells abound, including a newsreaders voice summing up last nights disasters, or a tape of your favourite early morning music. Still, getting out of bed has its difficult moments. All this could well change in the near future, if Ir. Stephan Wensveen, a graduate...
journal article 2002
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Hauschild, A. (author), Montenbruck, O. (author), Sleewaegen, J.M. (author), Huisman, L. (author), Teunissen, P.J.G. (author)
An analysis of observations from China’s first medium earth orbit satellite Compass M-1 is presented, with main focus on the first orbit and clock solution for this satellite. The orbit is computed from laser ranging measurements. Based on this orbit solution, the apparent clock offset is estimated using measurements from two GNSS receivers,...
journal article 2011
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Schiller, S. (author), Tino, G.M. (author), Gill, E. (author)
The Einstein Gravity Explorer mission (EGE) is devoted to a precise measurement of the properties of space-time using atomic clocks. It tests one of the most fundamental predictions of Einstein’s Theory of General Relativity, the gravitational redshift, and thereby searches for hints of quantum effects in gravity, exploring one of the most...
journal article 2008
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Van Bree, R.J.P. (author), Tiberius, C.C.J.M. (author)
The performance of real-time single-frequency precise point positioning is demonstrated in terms of position accuracy. This precise point positioning technique relies on predicted satellite orbits, predicted global ionospheric maps, and in particular on real-time satellite clock estimates. Results are presented using solely measurements from a...
journal article 2011
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Shen, Y. (author), Bootsman, R.J. (author), Alavi, S.M. (author), de Vreede, L.C.N. (author)
This article presents a wideband 2× 12 -bit direct-digital RF modulator (DDRM) operating in a 0.5-to-3-GHz band for 5G transmitters. The proposed digital Cartesian modulator features an advanced IQ-mapping technique to boost RF power by 3 dB and suppress the I/Q image. To verify the proposed concept, a 40-nm CMOS prototype is implemented...
journal article 2022
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Gong, J. (author), Charbon-Iwasaki-Charbon, E. (author), Sebastiano, F. (author), Babaie, M. (author)
This article presents a low-jitter and low-spur charge-sampling phase-locked loop (CSPLL). A charge-domain sub-sampling phase detector is introduced to achieve a high phase-detection gain and to reduce the PLL in-band phase noise. Even without employing any power-hungry isolation buffers, the proposed phase detector dramatically suppresses...
journal article 2022
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Li, Chao Chieh (author), Yuan, Min Shueh (author), Liao, Chia Chun (author), Chang, Chih Hsien (author), Lin, Yu Tso (author), Tsai, Tsung Hsien (author), Huang, Tien Chien (author), Liao, Hsien Yuan (author), Staszewski, R.B. (author)
In this article, we introduce a fractional-N all-digital phase-locked loop (ADPLL) architecture based on a single LC-tank, featuring an ultra-wide tuning range (TR) and optimized for ultra-low area in 10-nm FinFET CMOS. Underpinned by excellent switches in the FinFET technology, a high turn-on/off capacitance ratio of LC-tank switched...
journal article 2021
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Wang, Zhongkai (author), Choi, Minsoo (author), Lee, Kyoungtae (author), Park, Kwanseo (author), Liu, Zhaokai (author), Biswas, Ayan (author), Han, Jaeduk (author), Du, S. (author), Alon, Elad (author)
This article presents a 200-Gb/s pulse amplitude-modulation four-level (PAM-4) and 100-Gb/s non-return-to-zero (NRZ) transmitter (TX) in 28-nm CMOS technology. To achieve the target data rate, the output bandwidth and swing of the proposed TX are optimized by minimizing the output capacitance of the 4:1 multiplexer (MUX) and driver stage with...
journal article 2022
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Beikmirza, M.R. (author), Shen, Y. (author), de Vreede, L.C.N. (author), Alavi, S.M. (author)
We present a wideband, 12-bit four-way Doherty Cartesian digital transmitter (DTX) featuring an innovative 50%-LO signed I/Q interleaved up-conversion technique that enables close to perfect orthogonal I/Q summation. The DTX incorporates a compact four-way lumped-element Doherty power combining network to enhance its average efficiency at...
journal article 2021
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Chang, Ziyi (author), Zhang, Yunshan (author), Yang, Changgui (author), Luo, Yuxuan (author), Du, S. (author), Chen, Yong (author), Zhao, Bo (author)
The size of wireless systems is required to be reduced in many applications, such as ultra-low-power sensor nodes and wearable/implantable devices, where battery and crystal are the two main bottlenecks in system miniaturization. In recent years, battery-free radios based on wireless power transfer (WPT) have shown great potential in...
journal article 2022
Searched for: subject%3A%22Clocks%22
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