Development of PDMS-based micromachining process for microfluidic reconfigurable antennas /

Seyedpour Esmaeilzad, SeyedehNasim
The objective of this thesis is to develop fabrication methods to implement microfluidic-based reconfigurable antennas. As the initial structure, a microfluidic based reconfigurable antenna is developed for transmitarrays, which consists of a multi-layered structure incorporating a microfluidic channel to confine liquid metal. The microfluidic channels are fabricated using soft lithography techniques where the channel material is PDMS. PDMS-to-glass and PDMS-to-PDMS bonding processes are optimized to achieve a reservoir for the fluidic material. In particular, a split-ring resonator and a complementary split ring for transmitarray applications are manufactured using the optimized process. Instead of using direct metallization approach, which is inadequate because of the low surface strength of PDMS, a novel method is proposed for the bonding of two different surfaces. A thin layer of silicon dioxide (50 nm) is deposited on the metal layer before the oxygen plasma treatment. The oxygen plasma treatment is done for duration of 20 seconds at an RF power of 20 W. Bonding strength measurements are also performed in the frame of this thesis. It is noted that the bonding quality can be enhanced with the use of silicon dioxide intermediate layer. The other device that has been designed and manufactured is a frequency tunable patch antenna, which is formed by reconfiguring its dimension employing two rectangular patches that are joined to each other with a liquid metal channel. The microfluidic channel is created by applying the bonding method between PDMS and metallized glass layers. The antenna has two different operation modes: (i)The channel is empty and the antenna resonates at 10.68 GHz and (ii) the condition in which the channel is full of liquid metal and the antenna resonates at 9.62 GHz. In conclusion, microfluidic transmitarray and microfluidic reconfigurable antenna are fabricated using liquid metal channel embedded in the PDMS layer.


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This thesis includes the design, simulation, production and measurement of an asymmetric coplanar strip folded dipole antenna suitable to be used as an element in a linear array operating at S-band (2.7 GHz - 3.3 GHz). In this same manner, its usefulness as an array antenna is also explored in this thesis. This antenna element consists of a microstrip line feed, microstrip to coplanar stripline transition (BALUN) and asymmetric coplanar strip (ACPS) folded dipole. The planar folded dipole can be constructed...
Design of Irregularly Shaped Patch Antennas by using the Multiport Network Model
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The multiport network model (MNM) is an analytical method that is used to analyze microstrip antennas. MNM is based on defining ports along the periphery of the patch and evaluating the impedance matrix corresponding to these ports by using the Greenpsilas function for the cavity under the patch. For regular rectangular, triangular and circular patches, analytical expressions for the Greenpsilas function are available. In the analysis of irregular patches, Greenpsilas functions cannot be calculated explicit...
Development of multiband microstrip antennas for GPS applications
Önder, Mustafa Caner; Aydın Çivi, Hatice Özlem; Department of Electrical and Electronics Engineering (2019)
In this thesis study, the design, fabrication and measurements of dualband and triband circularly polarized microstrip antennas for GPS applications are presented. Characteristic mode analysis technique is applied to get an insight into circularly polarized patch antennas. A design flow is presented for a circularly polarized L1 GPS band microstrip antenna by using characteristic mode analysis. A single fed L1/L2 GPS band right hand circularly polarized four-slotted patch antenna is designed by using reacti...
Design of pattern reconfigurable antenna employing RF-MEMS switches
Gök, Çağlar; Alatan, Lale; Department of Electrical and Electronics Engineering (2022-8-17)
In this thesis, the design, simulations, fabrication and measurements of reconfigurable antennas for use in 5G Massive MIMO systems are presented. 26 GHz is chosen as the operating frequency and RF-MEMS switches are used as control elements for pattern reconfiguration. As a first step, a patch antenna is designed based on the excitation of different operation modes of different resonators. A circular patch in the center and a ring resonator structure around it are used to create different radiation patterns...
Design and realization a quasi yagi antenna array and its feed system printed on a ceramic substrate for x-band radar applications
Atabay, Berkay; Dural Ünver, Mevlüde Gülbin; Department of Electrical and Electronics Engineering (2019)
This thesis includes design, simulation, realization and measurement of a four-element quasi- Yagi antenna array printed on a ceramic substrate for X-band radar applications. The microstrip array antenna is designed using four quasi-Yagi antennas in a linear configuration and is printed on Alumina 99.6% substrate made by Coorstek Corporation. The antenna can fit into small areas because of compact structure due to the use of high dielectric constant substrates. In addition, the use of alumina ceramic substr...
Citation Formats
S. Seyedpour Esmaeilzad, “Development of PDMS-based micromachining process for microfluidic reconfigurable antennas /,” M.S. - Master of Science, Middle East Technical University, 2015.