title: Time averaged transmitter power and exposure to electromagnetic fields from mobile phone base stations.
abstract: Models for exposure assessment of high frequency electromagnetic fields from mobile phone base stations need the technical data of the base stations as input. One of these parameters, the Equivalent Radiated Power (ERP), is a time-varying quantity, depending on communication traffic. In order to determine temporal averages of the exposure, corresponding averages of the ERP have to be available. These can be determined as duty factors, the ratios of the time-averaged power to the maximum output power according to the transmitter setting. We determine duty factors for UMTS from the data of 37 base stations in the Swisscom network. The UMTS base stations sample contains sites from different regions of Switzerland and also different site types (rural/suburban/urban/hotspot). Averaged over all regions and site types, a UMTS duty factor for the 24 h-average is obtained, i.e., the average output power corresponds to about a third of the maximum power. We also give duty factors for GSM based on simple approximations and a lower limit for LTE estimated from the base load on the signalling channels.
authors.affiliation: ARIAS umwelt.forschung.beratung, Gutenbergstrasse 40B, CH-3011 Bern, Switzerland. alfred.buergi@arias.ch.
authors.forename: Alfred
authors.initials: A
authors.lastname: Bürgi
authors.affiliation: Swisscom (Switzerland) Ltd., Innovation, Mobile Access, Ey. 10, CH-3063 Ittigen, Switzerland. damiano.scanferla@swisscom.com.
authors.forename: Damiano
authors.initials: D
authors.lastname: Scanferla
authors.affiliation: Swisscom (Switzerland) Ltd., Innovation, Mobile Access, Ey. 10, CH-3063 Ittigen, Switzerland. hugo.lehmann@swisscom.com.
authors.forename: Hugo
authors.initials: H
authors.lastname: Lehmann
mesh_terms: D040421:Cell Phone; D004574:Electromagnetic Fields; D004781:Environmental Exposure; D008962:Models, Theoretical; D011834:Radiation Monitoring; D013557:Switzerland
references.citation: J Expo Sci Environ Epidemiol. 2008 Mar;18(2):183-91
references.pmid: 17410112
references.citation: Bioelectromagnetics. 2010 Apr;31(3):226-36
references.pmid: 19834920
references.citation: Sci Total Environ. 2013 Feb 15;445-446:202-9
references.pmid: 23333516
references.citation: J Expo Sci Environ Epidemiol. 2015 Jan;25(1):53-7
references.pmid: 24472756