Advisors
Now showing items 1-20 of 36
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Airborne cmut cell design
(Bilkent University, 2014)All transducers used in airborne ultrasonic applications, including capacitive micromachined ultrasonic transducers (CMUTs), incorporate loss mechanisms to have reasonably wide frequency bandwidth. However, CMUTs can yield ... -
Analysis of using OFDM for short-range, multı-user, underwater acoustic communication
(Bilkent University, 2006)Acoustic waves are being used in several underwater applications, such as SONARs, underwater communication systems. Most of already developed and deployed underwater communication systems use narrow band communication ... -
Barrel-stave flextensional transducer design
(Bilkent University, 2009)This thesis describes the design of low frequency, high power capability class-I flextensional, otherwise known as the barrel-stave, flextensional transducer. Piezoelectric ceramic rings are inserted inside the shell. ... -
Beam coding with spread spectrum orthogonal gold codes in underwater acoustic systems
(Bilkent University, 2015-10)In this study, the applicability of beam coding approaches enabling coded transmission with direct sequence spread spectrum (DSSS) signals to multiple high resolution beams in underwater acoustic systems is investigated. ... -
CD-MA-PMR network planning and optimization in İstanbul
(Bilkent University, 2006)The aim of this work is to design a complete PMR (Professional Mobile Radio) network based on CDMA 450 in Istanbul metropolitan region. Coverage and capacity analysis are performed by the developed simulation software ... -
Circuit theory based modeling and analysis of CMUT arrays
(Bilkent University, 2013)Many ultrasonic technology applications require capacitive micromachined ultrasonic transducers (CMUTs) to be used in the form of large arrays to attain better performance in terms of powerful, broadband and beam-formed ... -
Data acquisition system design for acoustic microscopy
(Bilkent University, 1996)Conventional acoustic microscopes suffer from the complexity and low speed of their scanning mechanisms. The frame rates of these instruments are low, while their cost are high. In this work, a data acquisition system ... -
Deep collapse mode capacitive micromachined ultrasonic transducers
(Bilkent University, 2010)Capacitive micromachined ultrasonic transducers (CMUTs) are suspended microelectromechanical membrane structures with a moving top electrode and a rigid substrate electrode. The membrane is actuated by electrical signals ... -
Design of 31-mode free-flooded ring transducers
(Bilkent University, 2008)In this work, design and electromechanical analysis of radially polarized 31-Mode freeflooded ring transducers which have high power capability in deep submergence are explained. 31-Mode free-flooded ring transducers ... -
Design of a wideband and bi-directional transducer for underwater communications
(Bilkent University, 2007)A two ceramic layer stacked transducer structure for short range underwater communications at high frequencies is studied in this work. The structure has a wide bandwidth of one octave and operates at 350 kHz center ... -
The design of a wideband and widebeam piston transducer in a finite closed circular baffle
(Bilkent University, 2008)The design of a high power piezoelectric underwater transducer operating at frequency range 42 kHz-78 kHz with acoustic power capability in excess of 250W is described. The transducer consists of two back-to-back elements. ... -
Design, fabrication and operation of a very high intensity CMUT transmit array for beam steering applications
(Bilkent University, 2020-12)Several studies have reported airborne ultrasound transmission systems focused on achieving beamforming. However, beam steering and beamforming for capacitive micromachined ultrasonic transducers (CMUTs) at high intensity ... -
Designing, fabrication and post- fabrication characterization of half-frequency driven 16 x 16 waterborne transmit CMUT array
(Bilkent University, 2021-02)Capacitive Micromachined Ultrasonic Transducers (CMUT) are micro-scaled electromechanical devices which are used to either transmit or receive pressure signals and applicable for various purposes such as ultrasonic sensor, ... -
Development and application of a ray tracing algorithm for propagation simulation in urban areas
(Bilkent University, 2002-08) -
Digital beamforming techniques and VLSI circuits for medical ultrasound imaging
(Bilkent University, 1992)For phased array medical ultrasound imaging, digital beamforming techniques and VLSI circuits are studied to form a fully digital receive front-end hardware. To increase the timing accuracy in beamforming, a computationally ... -
Effect of exercise on QT dispersion
(Bilkent University, 1998)Electrocardiogram (ECG) is the measurement of potential differences occurring on the body due to the currents that flow on the heart during diastole and systole. Cardiac abnormalities cause uncommon current flows, leading ... -
Electrically unbiased and half frequency driven waterborne 16×16-element 2-D phased array CMUT
(Bilkent University, 2019-08)Capacitive micromachined ultrasonic transducers (CMUT) are typically used as arrays consisting of separate cells or interconnected sub arrays, and these cells have several operation modes. Design procedure and ... -
Electromechanical filters using micromachined coupled circular plate resonators
(Bilkent University, 2021-09)Mechanically coupled resonators fabricated using micromachining usually require a mechanical coupling element; this introduces additional complexity to the picture. We propose a novel modeling and design approach, followed ... -
GSM and UMTS mobility simulator
(Bilkent University, 2005)In this thesis, a mobility simulator for GSM and UMTS has been designed and implemented using Visual C#.Net. The objective has been to design and implement such a simulator that can be used to create and study different ... -
Implementation of an OFDM based underwater acoustic modem
(Bilkent University, 2011)In this thesis we designed and implemented an underwater acoustic (UWA) communication system employing multicarrier modulation in the form of orthogonal frequency division multiplexing (OFDM). UWA communication became ...
