Analysis and design of dual-polarized wideband patch antennas electromagnetically excited with elevated wide strips /

Download
2015
Yılmaz, Adil Fırat
In communication systems like WiMAX, WLAN, 3G, 4G and LTE, design of wideband and dual polarized antennas are required. It is known that bandwidth of patch antennas can be broaden by using thick air substrates. The bandwidth can be further improved by using three dimensional feed strucutures that are electromagnetically coupled to the patch. In this thesis, microstrip patch antennas that are excited by elevated wide strips are studied. First, a linearly polarized antenna is considered and the effects of antenna and feed parameters on the input impedance characteristics are investigated through EM simulations. Then a dual polarized antenna is considered and the effects of antenna parameters on the radiation performance (i.e. isolation) is explored. In the light of these observations, guidelines for the design of dual polarized wideband patch antennas excited with elevated wide strips is presented. To demonstrate the usage of these guidelines an antenna, which operates in a different frequency band, is designed by following the steps of the proposed design procedure. Finally, the input impedance and radiation pattern measurements of a two element antenna array that was previously designed as a base station antenna are performed. Simulation and measurement results are compared and discussed. The EM simulations are performed by a Finite Element based full-wave analysis software HFSS by Ansys.

Suggestions

Modelling and analysis of vertical handover in highly mobile environments
Kirsal, Yonal; Ever, Enver; Koçyiğit, Altan; Gemikonakli, Orhan; Mapp, Glenford (2015-12-01)
Various types of wireless networks have been developed and deployed including 3G, WLAN, WiMAX, LTE and LTE Advanced. User connectivity and network performance can be improved using vertical handover techniques which involve switching between available networks in heterogeneous environments. In this respect, recently there has been an increased interest in the integration of cellular and WLAN systems. In this study, the integrated heterogeneous wireless systems are modelled using two-stage open queuing syste...
High speed LVDS digital input/output interface circuitries for high resolution imaging sensors /
Soyer, Suhip Tuncer; Akın, Tayfun; Eminoğlu, Selim; Department of Electrical and Electronics Engineering (2015)
In communication systems like WiMAX, WLAN, 3G, 4G and LTE, design of wideband and dual polarized antennas are required. It is known that bandwidth of patch antennas can be broaden by using thick air substrates. The bandwidth can be further improved by using three dimensional feed strucutures that are electromagnetically coupled to the patch. In this thesis, microstrip patch antennas that are excited by elevated wide strips are studied. First, a linearly polarized antenna is considered and the effects of ant...
Broadband loaded dipole antenna design by genetic algorithm optimization
Asan, Bahri; Koç, Seyit Sencer; Department of Electrical and Electronics Engineering (2014)
It is well known that standard dipole antenna is not convenient to be used in broadband wireless communication applications because of its narrow frequency bandwidth. To broaden the bandwidth of a dipole, lumped loading is the generally applied method. Positive effects of resistive, capacitive and inductive loading are discussed and proved for a pretty long time. This thesis investigates broadband lumped loaded dipole antenna design procedure by using genetic algorithm optimization techniques. First, unload...
Design of dual-frequency probe-fed microstrip antennas with genetic optimization algorithm
Ozgun, O; Mutlu, S; Aksun, MI; Alatan, Lale (2003-08-01)
Dual-frequency operation of antennas has become a necessity for many applications in recent wireless communication systems, such as GPS, GSM services operating at two different frequency bands, and services of PCS and IMT-2000 applications. Although there are various techniques to achieve dual-band operation from various types of microstrip antennas, there is no efficient design tool that has been incorporated with a suitable optimization algorithm. In this paper, the cavity-model based simulation tool alon...
Evaluation of priority dependent and time scheduled MAC layer protocols for ad-hoc networks
Erdeğer, İsmail; Baykal, Buyurman; Department of Electrical and Electronics Engineering (2015)
Ad-hoc networks have very unique features, such as dynamic topologies, relatively limited bandwidth and wireless signal propagation schemes, which present various challenges for wireless communication. In this thesis, control mechanisms for channel access scheduling and topology in ad-hoc networks are evaluated, which utilize the information from two-hop neighborhood to cope with the communication difficulties in ad-hoc networks. Channel assignment is one of the most important topics for ad-hoc networks. Ch...
Citation Formats
A. F. Yılmaz, “Analysis and design of dual-polarized wideband patch antennas electromagnetically excited with elevated wide strips /,” M.S. - Master of Science, Middle East Technical University, 2015.