Sökning: "Electro-Acoustics"

Hittade 4 avhandlingar innehållade ordet Electro-Acoustics.

1. 1. Thin Film Plate Acoustic Resonators for Frequency Control and Sensing Applications

   Författare :Lilia Arapan; Ventsislav Yantchev; Ilja Katardjiev; Enrique Iborra; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electro-Acoustics; FPAR; Lamb waves; aluminium nitride; interdigital transducer; phase noise; temperature compensation; power handling; sensitivity; zero group velocity; intermode coupling; Teknisk fysik med inriktning mot elektronik; Engineering Science with specialization in Electronics; Teknisk fysik med inriktning mot mikrosystemteknik; Engineering Science with specialization in Microsystems Technology;

   Sammanfattning : The recent development of the commercially viable thin film electro-acoustic technology has triggered a growing interest in the research of plate guided wave or Lamb wave components owing to their unique characteristics. In the present thesis i) an experimental study of the thin film plate resonators (FPAR) performance operating on the lowest symmetrical Lamb wave (S0) propagating in highly textured AlN membranes versus a variety of design parameters has been performed. LÄS MER

3. 2. Acoustical properties of earplugs

   Författare :Per Hiselius; Teknisk akustik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik; vibration and acoustic engineering; vacuum technology; hydraulics; Mechanical engineering; acoustic modelling; objective measurement; insertion loss; earplugs; HPE; HPD; hearing protectors; Two-Port; Four-Pole; attenuation; electro acoustics; acoustics;

   Sammanfattning : In this study an experimental setup for measurements of high impedance objects in ducts, yielding the acoustical Two-Port properties of the object, is applied to earplugs. A frequently used experimental setup for measuring objective acoustical properties of earplugs is that of artificial ears. Great effort is spent on duplicating the human ear. LÄS MER

4. 3. On Reverberation Enhancement in Auditoria

   Författare :Peter Svensson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; active sound field control; room acoustics; reverberation enhancement; listening tests; subjective effects; sound-reinforcement; feedback systems; feedback control; computer modelling of acoustics in enclosures; modulation; electro acoustics; time-varying filters;

   Sammanfattning : The analysis of electroacoustic systems for reverberation enhancement in auditoria is the topic of this thesis. Such systems have been developed since the 50's and been commercially available since then as well. During the 80's several new system ideas have been presented but there are still some open questions that are addressed here. LÄS MER

5. 4. Electro-Acoustic and Electronic Applications Utilizing Thin Film Aluminium Nitride

   Författare :David Michael Martin; J. Olsson; I. Katardjiev; S. Gevorgian; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; AlN; FBAR; FPAR; CMP; SOI; Nickel Silicide; Wafer Bonding; Electronics; Elektronik; Elektronik; Electronics;

   Sammanfattning : In recent years there has been a huge increase in the growth of communication systems such as mobile phones, wireless local area networks (WLAN), satellite navigation and various other forms of wireless data communication that have made analogue frequency control a key issue. The increase in frequency spectrum crowding and the increase of frequency into microwave region, along with the need for minimisation and capacity improvement, has shown the need for the development of high performance, miniature, on-chip filters operating in the low to medium GHz frequency range. LÄS MER