Exposure Compliance Methodologies for Multiple Input Multiple Output (MIMO) Enabled Networks and Terminals

Perentos, Nicholas; Iskra, Steve; Faraone, A.; McKenzie, Raymond J.; Bit-Babik, G.; Anderson, Vitas

doi:10.1109/tap.2011.2173453

Cited by 24 publications

(22 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the second case, the excitations vary in both amplitude and phase for a fixed transmitted power. Theoretically, Equation (3) provides a lower degree of overestimation compared with Equation (2), but the obtained combined electric field is in general not invariant under coordinate transformations [Perentos, 2012]. For the Random Phase method, a set of random phases is created for each field evaluation point.…”

Section: Methodsmentioning

confidence: 99%

Radio frequency electromagnetic field compliance assessment of multi‐band and MIMO equipped radio base stations

Thors

Thielens

Friden

et al. 2014

Bioelectromagnetics

View full text Add to dashboard Cite

In this paper, different methods for practical numerical radio frequency (RF) exposure compliance assessments of radio base station (RBS) products are investigated. Both multi-band base station antennas and antennas designed for multiple-input multiple-output (MIMO) transmission schemes are considered. For the multi-band case, various standardized assessment methods are evaluated in terms of resulting compliance distance with respect to the International Commission on Non-Ionizing Radiation Protection (ICNIRP) reference levels and basic restrictions. Both single frequency and multiple frequency (cumulative) compliance distances are determined, using numerical simulations for a mobile communication base station antenna transmitting in four frequency bands between 800 MHz and 2600 MHz. The assessments are conducted in terms of the root-mean squared electromagnetic field, the whole-body averaged SAR and the peak 10g averaged SAR. In general, assessments based on peak field strengths are found to be less computationally intensive but lead to larger compliance distances than spatial averaging of electromagnetic fields used in combination with localized SAR assessments. As long as adult exposure is considered, the results also indicate that even shorter compliance distances are obtained by using assessments based on localized and wholebody SAR. Numerical simulations, using base station products employing multiple-input multipleoutput (MIMO) transmission schemes, are performed as well and are in good agreement with reference measurements. The applicability of various field combination methods for correlated exposure is investigated, and best estimate methods are proposed. It is also shown, that field combining methods generally considered as conservative may be used to efficiently assess compliance boundary dimensions of single-and dual-polarized multicolumn base station antennas with only minor increases in compliance distances. Key words: Mobile communication; Electromagnetic field exposure; EMF compliance; SpecificAbsorption Rate; MIMO; Multi-standard radio base station; Multi-band radio base station. INTRODUCTIONBefore radio base station (RBS) products are placed on the market, their manufacturers conduct electromagnetic field (EMF) product compliance assessments to make sure that the equipment fulfills relevant regulatory requirements on EMF exposure. The purpose of these assessments is to determine compliance boundaries outside of which the radiofrequency (RF) EMF exposure is below applicable exposure limits. The most widely adopted exposure limits are specified by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) [ICNIRP, 1998]. For frequencies between 10 MHz to 10 GHz, including the frequency range used for mobile communications, the fundamental dosimetric quantity is the specific absorption rate (SAR). SAR corresponds to the rate of dissipated energy per unit mass within the exposed body due to the incident electromagnetic fields. Assessing exposure with respect to the basic re...

show abstract

Section: Methodsmentioning

confidence: 99%

Radio frequency electromagnetic field compliance assessment of multi‐band and MIMO equipped radio base stations

Thors

Thielens

Friden

et al. 2014

Bioelectromagnetics

View full text Add to dashboard Cite

show abstract

“…In addition to the work just described, the group has been involved in international efforts to develop measurement methodologies for new and emerging technologies [43] and to minimize electromagnetic compatibility issues in hospitals [44]. The group’s work has been assisted by the anechoic chamber facilities at Swinburne for both testing of measurement equipment and the quality assurance of biological exposure setups.…”

Section: Radiofrequency Researchmentioning

confidence: 99%

Lessons and Perspectives from a 25-Year Bioelectromagnetics Research Program

Wood

Lajevardipour

McIntosh

2016

IJERPH

View full text Add to dashboard Cite

The question of whether electromagnetic fields from electric power or telecommunications systems can be linked unequivocally to health detriments has occupied scientific research endeavors for nearly half a century. For 25 years, the bioelectromagnetic research group at Swinburne University in Melbourne, Australia, has pursued a series of investigations with relevant endpoints, such as neurophysiological and neuropsychological effects, cell calcium level changes, proliferation, and genotoxic effects. Most have shown no significant changes due to fields, however, in some pilot studies significant changes were revealed, but in most cases these were not replicated in follow-up studies. This highlights a feature of this research area, generally; the unambiguous identification of small changes in noisy data where the understanding of possible interaction mechanisms is lacking. On the other hand, mathematical modelling studies, particularly with respect to fields near metallic implants, in workers exposed to fields in harsh environmental conditions and at very high frequencies (THz), continue to add to the expanding knowledge database on the characteristics of the complex electromagnetic environment we live in today.

show abstract

“…To capture the simultaneous SAR values, exhaustive field measurements should be performed quickly over time and at multiple spatial points, which is impractical. In [2], field summation schemes and testing methodologies were proposed for the evaluation of simultaneous peak SAR. However, the schemes were shown to be conservative for multi-antenna devices.…”

Section: Introductionmentioning

confidence: 99%

Simple assessment of Specific Absorption Rate (SAR) for MIMO terminals

Lau

2015

2015 IEEE International Symposium on Antennas and Propagation &Amp; USNC/URSI National Radio Science Meeting

View full text Add to dashboard Cite

Abstract-Evaluating SAR for multi-antennas is difficult and impractical due to the arbitrary power allocation and phase of the electric fields from different antennas causing the total field to change randomly. In this context, a simple approach was recently proposed for assessing SAR when more than one antenna is transmitting simultaneously. The metric of time averaged simultaneous peak SAR (TASPS) was derived for the purpose of showing that only the stand-alone SAR for each antenna needs to be evaluated in order to verify if the SAR for multi-antenna transmissions also stays within the exposure limit. In this paper, we briefly review the derivation and illustrate the physical mechanism underlying this result for a two-antenna prototype using stand-alone and simultaneous SAR distributions.

show abstract

Exposure Compliance Methodologies for Multiple Input Multiple Output (MIMO) Enabled Networks and Terminals

Cited by 24 publications

References 3 publications

Radio frequency electromagnetic field compliance assessment of multi‐band and MIMO equipped radio base stations

Radio frequency electromagnetic field compliance assessment of multi‐band and MIMO equipped radio base stations

Lessons and Perspectives from a 25-Year Bioelectromagnetics Research Program

Simple assessment of Specific Absorption Rate (SAR) for MIMO terminals

Contact Info

Product

Resources

About