Meny

Javascript verkar inte påslaget? - Vissa delar av Lunds universitets webbplats fungerar inte optimalt utan javascript, kontrollera din webbläsares inställningar.
Du är här

Optimal Electromagnetic Measurements

Författare:
Publiceringsår: 2000
Språk: Engelska
Sidor:
Publikation/Tidskrift/Serie: Technical Report LUTEDX/(TEAT-7091)/1-24/(2000)
Volym: TEAT-7091
Dokumenttyp: Rapport
Förlag: [Publisher information missing]

Sammanfattning

We consider the problem of obtaining information about an inaccessible halfspace

from electromagnetic measurements made in the accessible half-space.

If the measurements are of limited precision, some scatterers will be undetectable

because their scattered fields are below the precision of the measuring

instrument. How can we make optimal measurements? In other words, what

incident fields should we apply that will result in the biggest measurements?

There are many ways to formulate this question, depending on the measuring

instruments. In this paper we consider a formulation involving wavesplitting

in the accessible half-space: what downgoing wave will result in an

upgoing wave of greatest energy? This formulation is most natural for far-field

problems.

A closely related question arises in the case when we have a guess about the

configuration of the inaccessible half-space. What measurements should we

make to determine whether our guess is accurate? In this case we compare the

scattered field to the field computed from the guessed configuration. Again

we look for the incident field that results in the greatest energy difference.

We show that the optimal incident field can be found by an iterative

process involving time reversal “mirrors”. For band-limited incident fields

and compactly supported scatterers, this iterative process converges to a sum

of time-harmonic fields.

Nyckelord

  • Electrical Engineering, Electronic Engineering, Information Engineering

Övriga

Published
  • Electromagnetic theory-lup-obsolete

Box 117, 221 00 LUND
Telefon 046-222 00 00 (växel)
Telefax 046-222 47 20
lu [at] lu.se

Fakturaadress: Box 188, 221 00 LUND
Organisationsnummer: 202100-3211
Om webbplatsen