Identification of electromagnetic scattering mechanisms by two dimensional windowed fourier transform approach

Download

index.pdf

Date

2004

Author

Germeç, K. Egemen

Metadata

Show full item record

Item Usage Stats

151
views

68
downloads

In this thesis, it is demonstrated that the two-dimensional Windowed Fourier Transform (WFT) can be effectively used to analyze the local spectral characteristics of electromagnetic scattering signals in the two-dimensional spatial frequency domain. The WFT is the extension of the Short Time Fourier Transform (STFT), which was originally derived to analyze the local spectral characteristics of one dimensional time functions. Since the WFT focuses on the local spectral behavior of the scattered field, the signal localization maps produced in the spectral domain by the WFT can be used to identify the contributions of the rays, at a given location in space, arising from various scattering mechanisms in high frequency applications.

Subject Keywords

Electrical engineering.

URI

http://etd.lib.metu.edu.tr/upload/12605608/index.pdf
https://hdl.handle.net/11511/14907

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Modelling and noise analysis of closed-loop capacitive sigma-delta mems accelerometer Boğa, Biter; Külah, Haluk; Department of Electrical and Electronics Engineering (2009) This thesis presents a detailed SIMULINK model for a conventional capacitive Σ-Δ accelerometer system consisting of a MEMS accelerometer, closed-loop readout electronics, and signal processing units (e.g. decimation filters). By using this model, it is possible to estimate the performance of the full accelerometer system including individual noise components, operation range, open loop sensitivity, scale factor, etc. The developed model has been verified through test results using a capacitive MEMS accelero...
A New Approach to Investigation of the Relationship of VLF Signals by Using Longitudinal Analysis Models Guzel, E.; Yaşar, M.; Kılıç, M. B.; Canyılmaz, M. (Hindawi Limited, 2013) Longitudinal analysis models are applied to analyze very low frequency (VLF) electromagnetic waves signals. They are useful in realization of nuance of relationship between parameters of concern which change over time. VLF data are so important for the communication and determining the disturbances in the lower ionosphere. In this study, we used a four-day VLF signal data which come from transmitter stations located at two different countries to Elazi. g receiver system. A very important feature of this dat...
Design and realization of broadband instantaneous frequency discriminator Pamuk, Gökhan; Yıldırım, Nevzat; Department of Electrical and Electronics Engineering (2010) n this thesis, RF sections of a multi tier instantaneous frequency measurement (IFM) receiver which can operate in 2 – 18 GHz frequency band is designed, simulated and partially realized. The designed structure uses one coarse tier, three medium tiers and one fine tier for frequency discrimination. A novel reflective phase shifting technique is developed which enables the design of very wideband phase shifters using stepped cascaded transmission lines. Compared to the classical phase shifters using coupled ...
HMIC miniaturization techniques and application on an FMCW range sensor transceiver Korkmaz, Hakan; Demir, Şimşek; Department of Electrical and Electronics Engineering (2010) This thesis includes the study of hybrid microwave integrated circuits (HMIC), miniaturization techniques applied on HMICs and its application on a frequency modulated continuous wave (FMCW) range sensor transceiver. In the scope of study, hybrid and monolithic microwave integrated circuits (HMIC and MMIC) are introduced, advantages and disadvantages of these two types are discussed. Large size of HMICs is the main disadvantage especially for military and civil applications requiring miniature volumes. This...
Design of dual polarized wideband microstrip antennas Yıldırım, Meltem; Alatan, Lale; Department of Electrical and Electronics Engineering (2010) In this thesis, a wideband dual polarized microstrip antenna is designed, manufactured and measured. Slot coupled patch antenna structure is considered in order to achieve the wideband characteristic. Although rectangular shaped slot coupled patch antennas are widely used in most of the applications, their utilization in dual polarized antenna structures is not feasible due to space limitations regarding the positioning of two separate coupling slots for each polarization. For a rectangular slot, the parame...

Citation Formats

K. E. Germeç, “Identification of electromagnetic scattering mechanisms by two dimensional windowed fourier transform approach,” M.S. - Master of Science, Middle East Technical University, 2004.