Results 21 to 30 of about 5,941,522 (258)

Influences of Sensor Placement Site and Subject Posture on Measurement of Respiratory Frequency Using Triaxial Accelerometers

Frontiers in Physiology, 2020
IntroductionRespiration frequency (RF) could be derived from the respiratory signals recorded by accelerometers which detect chest wall movements. The optimum direction of acceleration for accurate RF measurement is still uncertain. We aim to investigate
Stephen Hughes, Haipeng Liu, Dingchang Zheng   +2 more
doaj   +1 more source

User localisation using visual sensing and RF signal strength [PDF]

, 2008
In this paper, we simulate a museum scenario where we are concerned with identifying the exhibit that a person is observing. Many different technologies exist for determining the location of a user, including GPS, GSM and RF-id tags.
Ó Conaire, Ciarán, O'Connor, Noel E., Fogarty, Keith, O\u27Connor, Noel E., Brennan, Conor   +4 more
core   +2 more sources

Improved Phase Stabilization of a Radio-Over-Fiber Link Under Large and Fine Delay Tuning

IEEE Photonics Journal, 2015
In this paper, we propose and demonstrate a phase-stabilized radio-frequency (RF) reference transmission scheme by actively stabilizing the optical path delay of the fiber link.
Feifei Yin, Anxu Zhang, Yitang Dai, Jianqiang Li, Yue Zhou, Jian Dai, Kun Xu   +6 more
doaj   +1 more source

Statistical Analysis of Handover Process Performance in a Cellular Mobile Network in the City of Quito, Ecuador

Engineering Proceedings, 2023
This paper presents an overview of the findings in the handover (HO) process performance within three routes in Quito, Ecuador. We used the Net-Monitor Software to gather information from one of the three national mobile operators.
Ramiro Espinosa, Pablo Lupera-Morillo, Valdemar Farre, Roberto Maldonado, Ricardo Llugsi Cañar   +4 more
doaj   +1 more source

Joint Frequency and Time Transfer Over Optical Fiber With High-Precision Delay Variation Measurement Using a Phase-Locked Loop

IEEE Photonics Journal, 2019
We demonstrate a simultaneous frequency and time reference dissemination system over 80 km fiber with a phase-locked loop. The phase fluctuation of the transferred radio-frequency (RF) signal is compensated by adjusting the frequency of the ...
Xiaocheng Wang, Wei Wei, Zhangweiyi Liu, Daming Han, Nan Deng, Lingwei Yang, Weilin Xie, Yi Dong   +7 more
doaj   +1 more source

Research on the extension method of the main signal source of the synchrotron radiation device

Dianzi Jishu Yingyong
The main signal source is one of the key components of the synchrotron radiation device. It is not only used to generate the highly stable reference signals required by each subsystem of the synchrotron radiation light source, but also used to generate ...
Zhang Kai, Wei Yelong, Chen Qiuju, Wu Congfeng, Pang Jian, Tang Yungai, Du Baiting, Zhang Shancai, Feng Guangyao   +8 more
doaj   +1 more source

Optical Self-Interference Cancellation With Frequency Down-Conversion Based on Cascade Modulator

IEEE Photonics Journal, 2020
A novel approach to simultaneous radiofrequency self-interference cancellation (SIC) and frequency down-conversion in a unified system is proposed and demonstrated experimentally based on cascade Mach–Zehnder modulators (MZM). The local oscillator
Jiaojiao Wang, Yuehui Wang, Zhike Zhang, Zeping Zhao, Jianguo Liu   +4 more
doaj   +1 more source

Phase noise and jitter modeling for fractional-N PLLs [PDF]

Advances in Radio Science, 2007
We present an analytical phase noise model for fractional-N phase-locked loops (PLL) with emphasis on integrated RF synthesizers in the GHz range. The noise of the crystal reference, the voltage-controlled oscillator (VCO), the loop filter, the charge ...
S. A. Osmany, F. Herzel, K. Schmalz, W. Winkler   +3 more
doaj  

Analisis Coverage Planning dan Coverage Prediction di Existing Network eNodeB Jaringan 4G di Daerah Operasional Yogyakarta dan Magelang

Techne, 2018
Untuk meningkatkan kinerja jaringan 4G yang merupakan jaringan uji coba di Yogyakarta dan Magelang  maka harus dilakukan coverage planning pada daerah yang kurang optimal. Kurang optimalnya daerah ini dikarenakan cakupan dan kualitas Radio Frequency (RF)
Pilar Tiara Lelepadang, Eva Yovita Dwi Utami, Andreas Ardian Febrianto   +2 more
doaj   +1 more source

Surface-Mount Zero-Ohm Jumper Resistor Characterization in High-Speed Controlled Impedance Transmission Lines

Sensors, 2023
Zero-ohm resistors, also known as jumpers, are commonly used in early radio frequency (RF) prototypes as they can help engineers identify the most optimal engineering solution for their system or create application-specific hardware configurations in ...
Aleksandr Vasjanov, Vaidotas Barzdenas
doaj   +1 more source