The phase noise of an oscillator with a thin-film barium strontium titanate (BST) capacitive tuning element, or varactor, is characterised and benchmarked against the same oscillator with a silicon semiconductor junction varactor. Phase noise tracks closely with varactor Q within a specific voltage range as expected. Compared to the semiconductor varactor-based oscillator, the BST-based oscilla...

TOMBAK, Ali. Radio Frequency Applications of Barium Strontium Titanate Thin Film Tunable Capacitors. (Under the supervision of Amir S. Mortazawi). Properties of thin film barium strontium titanate (BST) based capacitors for RF and microwave components were studied. The capacitors were measured for their tunability, loss tangent, frequency dependence of dielectric permittivity, and behavior at l...

Barium Strontium Titanate (BST) varactors utilized in a VCO demonstrate unique tuning characteristics compared to junction varactors. A 2.7 GHz microstrip line VCO operates in a tracking phaselock loop configured as an X4 frequency multiplier. BST oscillator tuning and the effect on loop dynamics is observed by the intentional design of an under damped system. Oscillator noise correction and pe...

Barium-strontium titanate (BST) Ba0.6Sr 0.4 TiO3 and lanthanum-lithium titanate (LLT) La0.5Li0.5TiO3 nanopowders and thin films have been obtained via the modified Pechini route. Polyesterification and complexation processes of gel formation have been examined. Hypothetical models of coordinative polymers formed in sol-gel system have been suggested. It has been shown that BST and LLT solid sol...

The growing importance of nonlinear transmission lines for pulsed power and high microwave devices in defense industrial applications motivates material development system optimization. This study investigates composites manufactured with various volume loadings both magnetic (nickel zinc ferrite) dielectric (barium strontium titanate) inclusions a silicone matrix. Increasing the fraction bariu...

This paper presents the utilizing of ferroelectric material on antenna application. There are two different ferroelectric had been used on the proposed antennas which include of Barium Strontium Titanate (BST) and Bismuth Titanate (BiT), suitable for Access Points operating in the WLAN IEEE 802.11 b/g and WiMAX IEEE 802.16 within the range of 2.3 GHz to 2.5 GHz application. BST, which had been ...

VASANI, ANAND JITENDRA Design of Frequency Agile Circuits Using Barium Strontium Titanate Varactor. (Under the direction of Prof. Kevin G. Gard). Multi-standard and multi-band radio are the next milestone in the ever developing radio industry. Frequency agile circuits are an enabling technology which allows us to achieve this goal. It is a low cost and efficient technology that provides the nec...

Compositionally graded barium strontium titanate @(BaxSr12x)TiO3—BST, x50.75, 0.8, 0.9, and 1.0# thin films are fabricated by pulsed-laser deposition on a LaAlO3 substrate with (La0.7Sr0.3)MnO3 as the bottom electrode. A high dielectric permittivity and temperature characteristic without Curie–Weiss law are obtained. A tunability of over 70% is obtained at frequency of 1 MHz, which is higher th...

In most electronic materials the change in dielectric constant with applied electric field is an effect too small to be useful or even easily measurable. But for a special class of highpermittivity materials the effect can be quite pronounced. This chapter explores some challenges and opportunities for exploiting tunable dielectrics to make reconfigurable, adaptive, frequency-agile RF devices. ...

Through high-resolution electron microscopy, the surface structure of barium titanate and strontium titanate nanoparticles are found to be terminated by a TiO2 double layer. These results confirm prior observations of TiO2-rich surface reconstructions on strontium titanate nanoparticles made hydrothermally at high pH and single crystals prepared with wet chemical etching. Of all the reconstruct...