Monopulse wideband waveguide based travelling wave array antenna

Download
index.pdf
2017
Gültepe, Gökhan
Show full item record
87
views
53
downloads
A novel, travelling-wave, waveguide-based antenna array structure with dual-plane monopulse capability is developed. It is an end-fed, broad wall longitudinal slotted, ridged waveguide-based printed antenna array. Even if the structure is scalable, it is designed to operate in S-band. The structure consists of printed antennas on two interleaved waveguide arrays whose dimensions are shrinked to make interleaving operation possible to keep inter-element spacings the same in both the azimuth and elevation planes. The inherently wideband printed antennas, linearly tapered slot antennas (LTSA), are excited via probes inserted into the waveguides to control the amplitude of the radiated E-field to generate desired sum and difference patterns. These LTSAs are expected to eliminate the narrow frequency characteristics of the slots on waveguides, and to improve the bandwidth. Besides, the unit cell of the array is modelled as 5-port networks to handle the couplings between array elements by using their scattering parameters. The array with desired radiation patterns is generated by a code implementation, which chooses the preoptimized array elements with proper radiation control parameters in MATLABTM. Also, a method to improve radiation patterns is presented to ease the coupling related degredations in the radiation patterns. Finally, a 30-element monopulse array with 25 dB Taylor and Taylor-like difference distributions is generated in MATLABTM, simulated in HFSSTM, and manufactured. The manufactured array is measured in planar near-field measurement setup, and the measurement results are verified after the comparison with the simulated ones. 
Antenna arrays., Monopulse radar., Antennas (Electronics)., Broadband communication systems.
http://etd.lib.metu.edu.tr/upload/12621516/index.pdf
https://hdl.handle.net/11511/26710
Graduate School of Natural and Applied Sciences, Thesis

Suggestions

Design of magneto-electric dipole antenna for wideband communication systems
Alparslan, Semih; Alatan, Lale; Department of Electrical and Electronics Engineering (2018)
This thesis includes the design, simulation, production and measurement of a differential fed magneto-electric dipole antenna with cavity operating at ultrawideband (3.3 GHz – 10 GHz). This antenna consists of a differential feeding structure, an electric dipole, a magnetic dipole and a cavity. The ultra-wideband operation is achieved through the use of differential feeding structure and cavity. A step-by-step procedure is followed during the design process of the differential fed magneto-electric dipole an...
Theoretical investigation and design of wideband dielectric resonator antennas
Yüksel, Yılmaz Çağrı; Alatan, Lale; Department of Electrical and Electronics Engineering (2015)
The aim of this thesis is to utilize Dielectric Resonator Antennas (DRA) as array elements due to their advantages over other conventional antenna elements such as dipoles and microstrip patches. Depending on both the excitation mechanisms and the antenna shape, a Dielectric Resonator Antenna (DRA) provides its designer multiple independent degrees of freedom. In this thesis three antenna shapes, namely hemispherical, cylindrical and rectangular DRAs, are investigated. The cylindrical and the rectangular sh...
Wideband omnidirectional and sector coverage antenna arrays for base stations
Alatan, Lale (2018-01-01)
By using parallel strip line fed printed dipole antennas as array elements, an omnidirectional antenna array and a wide angle sector coverage array operating in octave band are designed. A maximum deviation of ±1.25 dB from the omnidirectional pattern is achieved for the omnidirectional array, and the average gain of the antenna was measured as being 5 dB in the 1.35–2.7GHz band. For the sector coverage array, a special reflector design is utilized to maintain a half power beam width of around 115◦ with a s...
Experimental performance evaluation of direction finding by amplitude comparison for GSM applications /
Karadağ, Savaş; Demir, Şimşek; Department of Electrical and Electronics Engineering (2014)
In this thesis, radio direction finding (DF) systems are examined, implementation and measurements for GSM mobile phones are done by using 6-element uniform circular Vivaldi antenna array and uniform circular monopole antenna array which is used asWatsonWatt antenna. Although degrading in performance of DF is expected, only one receiver unit is used in angle-of-arrival (AOA) to measure received signal strength (RSS) from each antenna elements to obtain low cost and small sized set-up. Moreover three di eren...
Beam Steerable Traveling Wave Meander Line Antenna Using Varactor Diode for X-Band Applications
Gokalp, Nihan; Aydın Çivi, Hatice Özlem (2008-07-11)
This paper presents a novel beam steerable meander line antenna with varactor diode for X-band applications. Beam steering has been achieved by loading the arms of the meander line antenna with varactor diodes. The capacitances of the varactor diodes have been controlled by DC bias voltage. Instead of varactor diodes, RF-MEMS variable capacitances can be used to scan the beam. Since the insertion loss of MEMS capacitances are small compared to loss of varactor diodes, use of MEMS capacitors will increase th...
Citation Formats
G. Gültepe, “Monopulse wideband waveguide based travelling wave array antenna,” M.S. - Master of Science, Middle East Technical University, 2017.
METU IIS - Integrated Information Service open@metu.edu.tr