Temporal and spatial forecasting of the foF2 values up to twenty four hours in advance

Tulunay, E
Ozkaptan, C
Tulunay, Yurdanur
Radio waves of a wide range of frequencies from very low frequency (VLF) to high frequency (HF), (broadly 3 to 30 MHz) can be propagated to great distances via the ionosphere.


Development of algorithms and software for forecasting, nowcasting and variability of TEC
Tulunay, E; Senalp, ET; Cander, LR; Tulunay, YK; Bilge, AH; Mizrahi, E; Kouris, SS; Jakowski, N (2004-01-01)
Total Electron Content (TEC) is an important characteristic of the ionosphere relevant to communications. Unpredictable variability of the ionospheric parameters due to various disturbances limits the efficiencies of communications, radar and navigation systems. Therefore forecasting and nowcasting of TEC are important in the planning and operation of Earth-space and satellite-to-satellite communication systems. Near-Earth space processes are complex being highly nonlinear and time varying with random varia...
Broadband spatial power combining in coaxial medium
Tanç, Zafer; Demir, Şimşek; Department of Electrical and Electronics Engineering (2012)
Microwave amplifiers having high output power are the essential components in many systems, such as radar and satellite communication. Although the structures generated by tube technologies fulfill the necessity of the required output power, the use of these amplifiers includes some critical drawbacks, one of which is the limited life of operation. Alternatively, solid-state amplifiers produced by transistor technology are preferred since they are high reliable devices. In order to provide the necessary out...
Frequency Modulated Continuous Wave Radar for Range Detection
Kaya, Tevfik; Sahin, Enes Burak; Nesimoglu, Tayfun (2018-11-02)
In this paper, a Frequency Modulated Continuous Wave Radar is built using radio frequency techniques. Radar can measure the nearest object's range from 2 to 30 meters with 1-meter range resolution. The design process was carried out by using computer-aided design techniques, and mathematical tools. The hardware prototype was built and measurements were carried out confirming successful operation of the range detection radar.
Communication Coverage in Wireless Passive Sensor Networks
Bereketli, Alper; Akan, Ozgur B. (2009-02-01)
System lifetime of wireless sensor networks (WSN) is inversely proportional to the energy consumed by critically energy-constrained sensor nodes during RF transmission. In that regard, modulated backscattering (MB) is a promising design choice, in which sensor nodes send their data just by switching their antenna impedance and reflecting the incident signal coming from an RF source. Hence, wireless passive sensor networks (WPSN) designed to operate using MB do not have the lifetime constraints of convention...
Short term variations of total electron content (TEC) fitting to a regional GPS network over the Kingdom of Saudi Arabia (KSA)
Alothman, A. O.; Alsubaie, M. A.; Ayhan, M. E. (Elsevier BV, 2011-09-01)
The ionosphere is a dispersive medium for radio waves with the refractive index which is a function of frequency and total electron content (TEC). TEC has a strong diurnal variation in addition to monthly, seasonal and solar cycle variations and small and large scale irregularities. Dual frequency GPS observations can be utilized to obtain TEC and investigate its spatial and temporal variations. We here studied short term TEC variations over the Kingdom of Saudi Arabia (KSA). A regional GPS network is forme...
Citation Formats
E. Tulunay, C. Ozkaptan, and Y. Tulunay, “Temporal and spatial forecasting of the foF2 values up to twenty four hours in advance,” PHYSICS AND CHEMISTRY OF THE EARTH PART C-SOLAR-TERRESTIAL AND PLANETARY SCIENCE, pp. 281–285, 2000, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/56994.