Dealing with crosstalk in electromagnetic field measurements of portable devices

2018 · Unclear · Moderate evidence

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UnclearModerate evidencePaper 1989

Study snapshot

Publicationmanual · 2018

Study typeexposure_assessment

Reported directionUnclear

Evidence ratingModerate

Abstract

Dealing with crosstalk in electromagnetic field measurements of portable devices Eeftens M, Struchen B, Roser K, Zahner M, Fröhlich J, Röösli M. Dealing with crosstalk in electromagnetic field measurements of portable devices. Bioelectromagnetics. 18 October 2018. doi.org Abstract Portable devices measuring radiofrequency electromagnetic fields (RF-EMF) are affected by crosstalk: signals originating in one frequency band that are unintentionally registered in another. If this is not corrected, total exposure to RF-EMF is biased, particularly affecting closely spaced frequency bands such as GSM 1800 downlink (1,805-1,880 MHz), DECT (1,880-1,900 MHz), and UMTS uplink (1,920-1,980 MHz). This study presents an approach to detect and correct crosstalk in RF-EMF measurements, taking into account the real-life setting in which crosstalk is intermittently present, depending on the exact frequency of the signal. Personal measurements from 115 volunteers from Zurich canton, Switzerland were analyzed. Crosstalk-affected observations were identified by correlation analysis, and replaced by the median value of the unaffected observations, measured during the same activity. DECT is frequently a victim of crosstalk, and an average of 43% of observations was corrected, resulting in an average exposure reduction of 38%. GSM 1800 downlink and UMTS uplink were less often corrected (6.9% and 8.9%), resulting in minor reductions in exposure (7.1% and 0.92%). The contribution of DECT to total RF-EMF exposure is typically already low (3.2%), but is further reduced after correction (3.0%). Crosstalk corrections reduced the total exposure by 1.0% on average. Some individuals had a larger reduction of up to 16%. The code developed to make the corrections is provided for free as an R function which is easily applied to any time series of EMF measurements. Conflicts of interest: Authors Jürg Fröhlich and Marco Zahner declare that they are involved in the company "Fields at Work," which manufactures the ExpoM-RF. onlinelibrary.wiley.com

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AI evidence extraction

Structured fields below were generated from the paper’s abstract and metadata to make the evidence easier to inspect. Automated extraction may be incomplete or incorrect; verify important details against the original paper.

Study typeexposure_assessment

Effect directionunclear

Population115 volunteers from Zurich canton, Switzerland

Sample size115

ExposureRF

Evidence strengthModerateConfidence: 78% · Peer reviewed: yes

Main findings

Portable RF-EMF measurement devices showed crosstalk between closely spaced bands (GSM 1800 downlink, DECT, UMTS uplink). Using correlation analysis to identify crosstalk-affected observations and replacing them with the median of unaffected observations during the same activity, an average of 43% of DECT observations were corrected with an average exposure reduction of 38%, while GSM 1800 downlink and UMTS uplink were corrected less often (6.9% and 8.9%) with smaller exposure reductions (7.1% and 0.92%); total exposure was reduced by 1.0% on average (up to 16% for some individuals).

Outcomes measured

Crosstalk detection in RF-EMF personal measurements
Crosstalk correction impact on band-specific exposure estimates (DECT, GSM 1800 downlink, UMTS uplink)
Change in total RF-EMF exposure estimate after correction

View raw extracted JSON

{
  "study_type": "exposure_assessment",
  "exposure": {
    "band": "RF",
    "source": "portable devices (personal RF-EMF measurements)",
    "frequency_mhz": null,
    "sar_wkg": null,
    "duration": null
  },
  "population": "115 volunteers from Zurich canton, Switzerland",
  "sample_size": 115,
  "outcomes": [
    "Crosstalk detection in RF-EMF personal measurements",
    "Crosstalk correction impact on band-specific exposure estimates (DECT, GSM 1800 downlink, UMTS uplink)",
    "Change in total RF-EMF exposure estimate after correction"
  ],
  "main_findings": "Portable RF-EMF measurement devices showed crosstalk between closely spaced bands (GSM 1800 downlink, DECT, UMTS uplink). Using correlation analysis to identify crosstalk-affected observations and replacing them with the median of unaffected observations during the same activity, an average of 43% of DECT observations were corrected with an average exposure reduction of 38%, while GSM 1800 downlink and UMTS uplink were corrected less often (6.9% and 8.9%) with smaller exposure reductions (7.1% and 0.92%); total exposure was reduced by 1.0% on average (up to 16% for some individuals).",
  "effect_direction": "unclear",
  "limitations": [],
  "evidence_strength": "moderate",
  "confidence": 0.78,
  "peer_reviewed_likely": "yes",
  "keywords": [
    "RF-EMF",
    "personal exposure measurement",
    "portable devices",
    "crosstalk",
    "frequency bands",
    "GSM 1800 downlink",
    "DECT",
    "UMTS uplink",
    "correlation analysis",
    "exposure correction",
    "ExpoM-RF",
    "R function"
  ],
  "suggested_hubs": []
}

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AI-extracted fields are generated from the abstract and metadata and may be incomplete or incorrect. This material is for informational purposes and is not medical advice.

Identifiers and source

DOI: 10.1002/bem.22142
PubMed: Not supplied

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