Results 21 to 30 of about 441,702 (217)
Study of P-350 cement setting kinetic by nuclear magnetic resonance
Materiales de Construccion, 1993 A kinetic study of cement setting process is presented in this paper A new method which allows the microscopic research of the evolution of the cement hydration applied to the study of three P-350 cuban cements is used.
Gabriel L. Duque Fernández +3 more
doaj +1 more source
A Compact Band-Notched UWB MIMO Antenna with Enhanced Isolation Using Comb Shaped Decoupling Element [PDF]
Radioengineering, 2023 A compact 37mm × 26 mm two element multiple-input-multiple-output (MIMO) antenna is presented for ultra wide band (UWB) system application with band notched characteristics.
S. Chatterjee, S. Rana, R. Sanyal
doaj
Performance Analysis of Millimeter Wave Massive MIMO Systems in Centralized and Distributed Schemes [PDF]
, 2018 This paper considers downlink multi-user millimeter-wave massive multiple-input multiple-output (MIMO) systems in both centralized and distributed configurations, referred to as C-MIMO and D-MIMO, respectively.
Li, Jing, Sun, Yichuang, Yue, Dian Wu
core +2 more sources
Machine-Learning-Aided Massive Hybrid Analog and Digital MIMO DOA Estimation for Future Wireless Networks [PDF]
Radioengineering, 2023 Due to a high spatial angle resolution and low circuit cost of massive hybrid analog and digital (HAD) multiple-input multiple-output (MIMO), it is viewed as a valuable green communication technology for future wireless networks.
X. Zhao +11 more
doaj
MIMO Radar Ambiguity Properties and Optimization Using Frequency-Hopping Waveforms [PDF]
, 2008 The concept of multiple-input multiple-output (MIMO) radars has drawn considerable attention recently. Unlike the traditional single-input multiple-output (SIMO) radar which emits coherent waveforms to form a focused beam, the MIMO radar can transmit ...
Chen, Chun-Yang, Vaidyanathan, P. P.
core +2 more sources
IEEE Signal Processing Magazine, 2008 Radio regulatory bodies are recognizing that the rigid spectrum assignment granting exclusive use to licensed services is highly inefficient, due to the high variability of the traffic statistics across time, space, and frequency. Recent Federal Communications Commission (FCC) measurements show that, in fact, the spectrum usage is typically ...
SCUTARI, GESUALDO +2 more
openaire +3 more sources
Non-Uniform Constellations for Polarization Division Multiplexed CO-OFDM Systems [PDF]
Radioengineering, 2021 In this paper we propose a~transmission scheme for Coherent Optical Orthogonal Frequency Division Multiplexing (CO-OFDM) systems with Multiple Input - Multiple Output (MIMO) processing.
D. Perez-Calderon +3 more
doaj
Time-Varying Kelvin Wake Model and Microwave Velocity Observation
Sensors, 2020 In the synthetic aperture radar (SAR) imaging of ship-induced wakes, it is difficult to obtain the Doppler velocity of a Kelvin wake due to the lack of time-varying wake models and suitable radar equipment.
Jie Niu, Xingdong Liang, Xin Zhang
doaj +1 more source
2012 IEEE Global Communications Conference (GLOBECOM), 2012 In a generic switching problem, a switching pattern consists of a one-to-one mapping from a set of inputs to a set of outputs (i.e., a permutation). We propose and investigate a wireless switching framework in which a multi-antenna relay is responsible for switching traffic among a set of $N$ stations. We refer to such a relay as a MIMO switch.
Wang, Fanggang, Liew, Soung Chang
openaire +2 more sources
Spatial data stream multiplexing scheme for high-throughput WLANs [PDF]
, 2008 A novel scheme using spatial data stream multiplexing (SDSM) in the upcoming multiple-input multipleoutput (MIMO)-based IEEE 802.11n physical layer is proposed.
Gravalos, AG +3 more
core +1 more source