Connect with us

Difference between a SAW resonator and a SAW filter?

Discussion in 'Electronic Design' started by billcalley, Jun 12, 2005.

Scroll to continue with content
  1. billcalley

    billcalley Guest

    Hi All,

    What is the difference between a SAW resonator and a SAW filter? Are
    they interchangeable? (I.E. Will a SAW resonator act as a filter; and
    can a SAW filter be used as the frequency determining element in a
    UHF/VHF oscillator?).

    Thanks!

    Bill
     
  2. doug dwyer

    doug dwyer Guest

    A SAW delay line filter can be thought of as two antenna facing each
    other that operate not in the electromagnetic domain but in the acoustic
    domain.
    Each "antenna" is an interdigitated transducer the bandwidth of the
    transducer is a function of the length, i.e. number of interdigitated
    transducer pairs.
    The overall bandwidth will be that of the combination of the two
    transducers.
    Complications are that a simple transducer is bidirecional but more
    modern transducers are unidirecional like yagi antennae.
    If only one transducer is used and mirror gratings are placed in front
    and behind then the lost bidirecional energy is reflected back and
    forward i.e. you have a resonator.
    Two transducers between the mirrors gives a 2 port resonator.
    Resonators make low loss narrow band filters delay line filters can be
    wide band the more loss the better shape and bandwidth.
     
  3. billcalley

    billcalley Guest

    Thanks Doug!

    Bill
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-