Results 31 to 40 of about 618,348 (165)

The First Results of Ionospheric Skywave Propagation Experiment Over Taiwan

Radio Science, Volume 61, Issue 1, January 2026.
Abstract An ionospheric over‐the‐horizon propagation experiment was carried out in Taiwan to investigate characteristics of ionospheric F layer skywave propagation at frequencies 4–12 MHz. Experimental results show that there are prominent diurnal variations in the incident angle, virtual height and plasma frequency at reflection height, which are ...
Hung‐Shi Lin, Ching‐Lun Su, Kang‐Hung Wu, Yen‐Hsyang Chu   +3 more
wiley   +1 more source

A Frequency Selection Method For Hf-Oth Skywave Radar Systems

, 2006
Publication in the conference proceedings of EUSIPCO, Florence, Italy ...
Capria A, BERIZZI, FABRIZIO, Soleti R, DALLE MESE, ENZO   +3 more
openaire   +4 more sources

Time Synchronisation for Passive Bistatic HFSWR via Kalman‐Filtered Delay‐Locked Loop

IET Radar, Sonar &Navigation, Volume 20, Issue 1, January/December 2026.
This paper proposes a per‐chirp time synchronisation method, FLOS‐Kalman‐DLL, for passive bistatic high‐frequency surface wave radar (HFSWR) operating under the coexistence of clock drift and atmospheric impulsive noise. The method combines fractional lower‐order statistics with a Kalman‐filtered delay‐locked loop to achieve sub‐sample synchronisation ...
Yuan Lu, Jie Song, Wei Xiong, Yaqi Cui
wiley   +1 more source

Intelligent Systems for Beyond‐Line‐of‐Sight Defense Communication: Technologies, Case Studies, and Research Frontiers

International Journal of Intelligent Systems, Volume 2026, Issue 1, 2026.
Beyond‐line‐of‐sight (BLOS) communication is a fundamental component of modern defense strategies, enabling secure and reliable information exchange in environments where traditional line‐of‐sight (LOS) methodologies are ineffective due to obstructions or operational constraints.
Shumaila Javaid, Ruhul Amin Khalil, Muhammad Haris, Farman Ullah, Nasir Saeed, Kallol Mohanta   +5 more
wiley   +1 more source

Decoding Brain Tumors: Comprehensive Insights into Detection and Evaluation Approaches

Engineering Reports, Volume 7, Issue 12, December 2025.
Comparison of brain tumor analysis techniques reveals that hybrid and ensemble models offer superior accuracy and generalization, while traditional ML provides higher interpretability and lower computational cost. This radar chart highlights the trade‐offs across five critical performance dimensions.
Anusha Nalajala, Inturi Anitha Rani, Olutayo O Oyerinde, Avinash Yadav, Nishant Kumar   +4 more
wiley   +1 more source

Examination of the effect of array weighting function on radar target detectability [PDF]

, 2010
This paper describes a methodology to assess the detectability of targets by anairborne fire control radar operating in a medium PRF mode in the presence of strongground clutter as a function of the transmitting and receiving antenna array ...
Alabaster, Clive M., C. M. Alabaster, E. J. Hughes, Hughes, Evan J.   +3 more
core   +1 more source

Advancing Ensemble Streamflow Prediction Through Satellite‐Based Precipitation Product and Model Parameter Uncertainty Quantification

Journal of Advances in Modeling Earth Systems, Volume 17, Issue 10, October 2025.
Abstract Satellite‐based quantitative precipitation estimates (QPE), such as NASA's Integrated Multi‐satellitE Retrievals for GPM (IMERG), provide easily accessible continental‐to‐global precipitation forcings for flood prediction and other hydrologic applications.
Kaidi Peng, Daniel B. Wright, Yagmur Derin, G. Aaron Alexander, Ankita Pradhan, Davide Zoccatelli, Samantha H. Hartke, Zhe Li, Jackson Tan   +8 more
wiley   +1 more source

Development of a MIMO Radar System Demonstrator - Calibration and Demonstration of First Results [PDF]

, 2012
The success of current spaceborne Synthetic Aperture Radar (SAR) is boosting the performance requirements of next generation systems. In order to cope with the evolution of SAR the design of the new systems will need to meet higher requirements for ...
A. Patyuchenko, Patyuchenko, Anton, Laskowski, Piotr, T. Rommel, Younis, Marwan, G. Krieger, Krieger, Gerhard, M. Younis, Rommel, Tobias, P. Laskowski   +9 more
core   +1 more source

Fault Network Geometry Modulates Earthquake Source Spectra Across Scales

Geophysical Research Letters, Volume 52, Issue 12, 28 June 2025.
Abstract Earthquake source spectra provide unique insights into the earthquake rupture process. Motivated by previous research suggesting that complex fault geometries enhance high‐frequency seismic radiation, we study the influence of fault network geometry on earthquake source spectra using multiple independent observations.
Jaeseok Lee, Victor C. Tsai, Daniel T. Trugman, Greg Hirth, Avigyan Chatterjee   +4 more
wiley   +1 more source

Ambiguity and area preserving linear transformations in over‐the‐horizon radar

IET Radar, Sonar &Navigation, Volume 19, Issue 1, January/December 2025.
The use of recurrent waveforms in over‐the‐horizon radar (OTHR) necessitates techniques for ambiguity resolution and manipulation. In this paper, the authors elucidate methods for systematically transforming any given waveform so that its ambiguity function is transformed by any desired area preserving the linear transformation of the delay‐Doppler ...
Stephen D. Howard, Van Khanh Nguyen
wiley   +1 more source