Abstract:
:Ultra-wideband (UWB) electromagnetic pulses of nanosecond duration, or nanopulses, have recently been approved by the Federal Communications Commission for a number of different applications. They are also being explored for applications in biotechnology and medicine. The simulation of the propagation of a nanopulse through biological matter, previously performed using a two-dimensional finite-difference time-domain (FDTD) method, has been extended here into a full three-dimensional computation. To account for the UWB frequency range, the geometrical resolution of the exposed sample was 0.25 mm and the dielectric properties of biological matter were accurately described in terms of the Debye model. The results obtained from the three-dimensional computation support the previously obtained results: the electromagnetic field inside a biological tissue depends on the incident pulse rise time and width, with increased importance of the rise time as the conductivity increases; no thermal effects are possible for the low pulse repetition rates, supported by recent experiments. New results show that the dielectric sample exposed to nanopulses behaves as a dielectric resonator. For a sample in a cuvette, we obtained the dominant resonant frequency and the Q-factor of the resonator.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Simicevic Ndoi
10.1088/0031-9155/50/21/007subject
Has Abstractpub_date
2005-11-07 00:00:00pages
5041-53issue
21eissn
0031-9155issn
1361-6560pii
S0031-9155(05)01601-5journal_volume
50pub_type
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