title: Dosimetry evaluation of a cylindrical waveguide chamber for unrestrained small rodents at 1.9 GHz.
abstract: An exposure system, consisting of four identical cylindrical waveguide chambers, was developed for studying the effects of radiofrequency (RF) energy on laboratory mice at a frequency of 1.9 GHz. The chamber was characterized for RF dose rate as a function of animal body mass and dose rate variations due to animal movement in the cage. Dose rates were quantified in terms of whole-body average (WBA) specific absorption rate (SAR), brain average (BA) SAR and peak spatial-average (PSA) SAR using measurement and computational methods. Measurements were conducted on mouse cadavers in a multitude of possible postures and positions to evaluate the variations of WBA-SAR and its upper and lower bounds, while computations utilizing the finite-difference time-domain method together with a heterogeneous mouse model were performed to determine variations in BA-SAR and the ratio of PSA-SAR to WBA-SAR. Measured WBA-SAR variations were found to be within the ranges of 9-23.5 W/kg and 5.2-13.8 W/kg per 1 W incident power for 20 and 40 g mice, respectively. Computed BA-SAR variations were within the ranges of 3.2-10.1 W/kg and 3.3-9.2 W/kg per 1 W incident power for 25 and 30 g mouse models, respectively. Ratios of PSA-SAR to WBA-SAR, averaged over 0.5 mg and 5 mg tissue volumes, were observed to be within the ranges of 6-15 and 4-10, respectively.
authors.affiliation: Faculty of Engineering, Rajamangala University of Technology Isan Khonkaen Campus, Khon Kaen, Thailand.
authors.forename: Siriwat
authors.initials: S
authors.lastname: Wasoontarajaroen
authors.forename: Artnarong
authors.initials: A
authors.lastname: Thansandote
authors.forename: Gregory B
authors.initials: GB
authors.lastname: Gajda
authors.forename: Eric P
authors.initials: EP
authors.lastname: Lemay
authors.forename: James P
authors.initials: JP
authors.lastname: McNamee
authors.forename: Pascale V
authors.initials: PV
authors.lastname: Bellier
mesh_terms: D000818:Animals; D001921:Brain / Q000528:radiation effects; D051379:Mice; D011874:Radiometry / Q000295:instrumentation*; D013997:Time Factors; D035501:Uncertainty